ffmpeg_sidecar::command

Struct FfmpegCommand

Source
pub struct FfmpegCommand { /* private fields */ }
Expand description

A wrapper around std::process::Command with some convenient preset argument sets and customization for ffmpeg specifically.

The rustdoc on each method includes relevant information from the FFmpeg documentation: https://ffmpeg.org/ffmpeg.html. Refer there for the exhaustive list of possible arguments.

Implementations§

Source§

impl FfmpegCommand

Source

pub fn hide_banner(&mut self) -> &mut Self

alias for -hide_banner argument.

Suppress printing banner.

All FFmpeg tools will normally show a copyright notice, build options and library versions. This option can be used to suppress printing this information.

Examples found in repository?
examples/sockets.rs (line 22)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
More examples
Hide additional examples
examples/named_pipes.rs (line 30)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn format<S: AsRef<str>>(&mut self, format: S) -> &mut Self

Alias for -f argument, the format name.

Force input or output file format. The format is normally auto detected for input files and guessed from the file extension for output files, so this option is not needed in most cases.

Examples found in repository?
examples/ffplay_preview.rs (line 16)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
More examples
Hide additional examples
examples/sockets.rs (line 25)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/named_pipes.rs (line 33)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn input<S: AsRef<str>>(&mut self, path_or_url: S) -> &mut Self

Alias for -i argument, the input file path or URL.

To take input from stdin, use the value - or pipe:0.

Examples found in repository?
examples/ffplay_preview.rs (line 17)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
More examples
Hide additional examples
examples/sockets.rs (line 26)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/h265_transcode.rs (line 25)
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fn main() {
  // Create an H265 source video as a starting point
  let input_path = "output/h265.mp4";
  if !Path::new(input_path).exists() {
    create_h265_source(input_path);
  }

  // One instance decodes H265 to raw frames
  let mut input = FfmpegCommand::new()
    .input(input_path)
    .rawvideo()
    .spawn()
    .unwrap();

  // Frames can be transformed by Iterator `.map()`.
  // This example is a no-op, with frames passed through unaltered.
  let transformed_frames = input.iter().unwrap().filter_frames();

  // You could easily add some "middleware" processing here:
  // - overlay or composite another RGB image (or even another Ffmpeg Iterator)
  // - apply a filter like blur or convolution
  // Note: some of these operations are also possible with FFmpeg's (somewhat arcane)
  // `filtergraph` API, but doing it in Rust gives you much finer-grained
  // control, debuggability, and modularity -- you can pull in any Rust crate
  // you need.

  // A second instance encodes the updated frames back to H265
  let mut output = FfmpegCommand::new()
    .args([
      "-f", "rawvideo", "-pix_fmt", "rgb24", "-s", "600x800", "-r", "30",
    ]) // note: should be possible to infer these params from the source input stream
    .input("-")
    .args(["-c:v", "libx265"])
    .args(["-y", "output/h265_overlay.mp4"])
    .spawn()
    .unwrap();

  // Connect the two instances
  let mut stdin = output.take_stdin().unwrap();
  thread::spawn(move || {
    // `for_each` blocks through the end of the iterator,
    // so we run it in another thread.
    transformed_frames.for_each(|f| {
      stdin.write_all(&f.data).ok();
    });
  });

  // On the main thread, run the output instance to completion
  output.iter().unwrap().for_each(|e| match e {
    FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
    FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
    _ => {}
  });
}
examples/named_pipes.rs (line 34)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn output<S: AsRef<str>>(&mut self, path_or_url: S) -> &mut Self

Alias for the output file path or URL.

To send output to stdout, use the value - or pipe:1.

Since this is the last argument in the command and has no - flag preceding it, it is equivalent to calling .arg() directly. However, using this command helps label the purpose of the argument, and makes the code more readable at a glance.

Examples found in repository?
examples/metadata.rs (line 9)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
More examples
Hide additional examples
examples/ffplay_preview.rs (line 20)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
examples/sockets.rs (line 39)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/named_pipes.rs (line 47)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn overwrite(&mut self) -> &mut Self

Alias for -y argument: overwrite output files without asking.

Examples found in repository?
examples/metadata.rs (line 8)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
More examples
Hide additional examples
examples/sockets.rs (line 23)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/named_pipes.rs (line 31)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn no_overwrite(&mut self) -> &mut Self

Alias for -n argument: do not overwrite output files, and exit immediately if a specified output file already exists.

Source

pub fn codec_video<S: AsRef<str>>(&mut self, codec: S) -> &mut Self

Alias for -c:v argument.

Select an encoder (when used before an output file) or a decoder (when used before an input file) for one or more video streams. codec is the name of a decoder/encoder or a special value `copy`` (output only) to indicate that the stream is not to be re-encoded.

Examples found in repository?
examples/ffplay_preview.rs (line 18)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
Source

pub fn codec_audio<S: AsRef<str>>(&mut self, codec: S) -> &mut Self

Alias for -c:a argument.

Select an encoder (when used before an output file) or a decoder (when used before an input file) for one or more audio streams. codec is the name of a decoder/encoder or a special value copy (output only) to indicate that the stream is not to be re-encoded.

Source

pub fn codec_subtitle<S: AsRef<str>>(&mut self, codec: S) -> &mut Self

Alias for -c:s argument.

Select an encoder (when used before an output file) or a decoder (when used before an input file) for one or more subtitle streams. codec is the name of a decoder/encoder or a special value copy (output only) to indicate that the stream is not to be re-encoded.

Source

pub fn duration<S: AsRef<str>>(&mut self, duration: S) -> &mut Self

Alias for -t argument.

When used as an input option (before -i), limit the duration of data read from the input file.

When used as an output option (before an output url), stop writing the output after its duration reaches duration.

duration must be a time duration specification, see (ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual.

-to and -t are mutually exclusive and -t has priority.

Source

pub fn to<S: AsRef<str>>(&mut self, position: S) -> &mut Self

Alias for -to argument.

Stop writing the output or reading the input at position. position must be a time duration specification, see (ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual.

-to and -t (aka duration()) are mutually exclusive and -t has priority.

Source

pub fn limit_file_size(&mut self, size_in_bytes: u32) -> &mut Self

Alias for -fs argument.

Set the file size limit, expressed in bytes. No further chunk of bytes is written after the limit is exceeded. The size of the output file is slightly more than the requested file size.

Source

pub fn seek<S: AsRef<str>>(&mut self, position: S) -> &mut Self

Alias for -ss argument.

When used as an input option (before -i), seeks in this input file to position. Note that in most formats it is not possible to seek exactly, so ffmpeg will seek to the closest seek point before position. When transcoding and -accurate_seek is enabled (the default), this extra segment between the seek point and position will be decoded and discarded. When doing stream copy or when -noaccurate_seek is used, it will be preserved.

When used as an output option (before an output url), decodes but discards input until the timestamps reach position.

position must be a time duration specification, see (ffmpeg-utils)the Time duration section in the ffmpeg-utils(1) manual.

Source

pub fn seek_eof<S: AsRef<str>>(&mut self, position: S) -> &mut Self

Alias for -sseof argument.

Like the -ss option but relative to the “end of file”. That is negative values are earlier in the file, 0 is at EOF.

Source

pub fn filter<S: AsRef<str>>(&mut self, filtergraph: S) -> &mut Self

Alias for -filter argument.

Create the filtergraph specified by filtergraph and use it to filter the stream.

filtergraph is a description of the filtergraph to apply to the stream, and must have a single input and a single output of the same type of the stream. In the filtergraph, the input is associated to the label in, and the output to the label out. See the ffmpeg-filters manual for more information about the filtergraph syntax.

See the -filter_complex option if you want to create filtergraphs with multiple inputs and/or outputs.

Source

pub fn crf(&mut self, crf: u32) -> &mut Self

Alias for ‘-crf:v’ argument.

Set CRF (Constant Rate Factor) for quality-based VBR (Variable BitRate)

Use this rate control mode if you want to keep the best quality and care less about the file size. Lower values means better quality with bigger average bitrate (0 usually means lossless).

Possible values depend on codec:

Source

pub fn frames(&mut self, framecount: u32) -> &mut Self

Alias for -frames:v argument.

Stop writing to the stream after framecount frames.

See also: -frames:a (audio), -frames:d (data).

Source

pub fn preset<S: AsRef<str>>(&mut self, preset: S) -> &mut Self

Alias for -preset:v argument.

Set preset which is basically trade-off between encoding speed and compression ratio.

For h264 and h265 allowed values are:

  • ultrafast
  • superfast
  • veryfast
  • faster
  • medium (default preset)
  • slow
  • slower
  • veryslow
  • placebo

For svt-av1 supported values 0-13 (higher number providing a higher encoding speed). Prior to version 0.9.0 valid values was 0-8.

For libaom supported values 0-11 (higher number providing a higher encoding speed)

VP9 has no presets

Source

pub fn rate(&mut self, fps: f32) -> &mut Self

Alias for -r argument.

Set frame rate (Hz value, fraction or abbreviation).

As an input option, ignore any timestamps stored in the file and instead generate timestamps assuming constant frame rate fps. This is not the same as the -framerate option used for some input formats like image2 or v4l2 (it used to be the same in older versions of FFmpeg). If in doubt use -framerate instead of the input option -r.

Source

pub fn size(&mut self, width: u32, height: u32) -> &mut Self

Alias for -s argument.

Set frame size.

As an input option, this is a shortcut for the video_size private option, recognized by some demuxers for which the frame size is either not stored in the file or is configurable – e.g. raw video or video grabbers.

As an output option, this inserts the scale video filter to the end of the corresponding filtergraph. Please use the scale filter directly to insert it at the beginning or some other place.

The format is 'wxh' (default - same as source).

Source

pub fn no_video(&mut self) -> &mut Self

Alias for -vn argument.

As an input option, blocks all video streams of a file from being filtered or being automatically selected or mapped for any output. See -discard option to disable streams individually.

As an output option, disables video recording i.e. automatic selection or mapping of any video stream. For full manual control see the -map option.

Source

pub fn pix_fmt<S: AsRef<str>>(&mut self, format: S) -> &mut Self

Alias for -pix_fmt argument.

Set pixel format. Use -pix_fmts to show all the supported pixel formats. If the selected pixel format can not be selected, ffmpeg will print a warning and select the best pixel format supported by the encoder. If pix_fmt is prefixed by a +, ffmpeg will exit with an error if the requested pixel format can not be selected, and automatic conversions inside filtergraphs are disabled. If pix_fmt is a single +, ffmpeg selects the same pixel format as the input (or graph output) and automatic conversions are disabled.

Examples found in repository?
examples/sockets.rs (line 38)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
More examples
Hide additional examples
examples/named_pipes.rs (line 46)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn hwaccel<S: AsRef<str>>(&mut self, hwaccel: S) -> &mut Self

Alias for -hwaccel argument.

Use hardware acceleration to decode the matching stream(s). The allowed values of hwaccel are:

  • none: Do not use any hardware acceleration (the default).
  • auto: Automatically select the hardware acceleration method.
  • vdpau: Use VDPAU (Video Decode and Presentation API for Unix) hardware acceleration.
  • dxva2: Use DXVA2 (DirectX Video Acceleration) hardware acceleration.
  • d3d11va: Use D3D11VA (DirectX Video Acceleration) hardware acceleration.
  • vaapi: Use VAAPI (Video Acceleration API) hardware acceleration.
  • qsv: Use the Intel QuickSync Video acceleration for video transcoding.
    • Unlike most other values, this option does not enable accelerated decoding (that is used automatically whenever a qsv decoder is selected), but accelerated transcoding, without copying the frames into the system memory.
    • For it to work, both the decoder and the encoder must support QSV acceleration and no filters must be used.

This option has no effect if the selected hwaccel is not available or not supported by the chosen decoder.

Note that most acceleration methods are intended for playback and will not be faster than software decoding on modern CPUs. Additionally, ffmpeg will usually need to copy the decoded frames from the GPU memory into the system memory, resulting in further performance loss. This option is thus mainly useful for testing.

Source

pub fn no_audio(&mut self) -> &mut Self

Alias for -an argument.

As an input option, blocks all audio streams of a file from being filtered or being automatically selected or mapped for any output. See -discard option to disable streams individually.

As an output option, disables audio recording i.e. automatic selection or mapping of any audio stream. For full manual control see the -map option.

Source

pub fn map<S: AsRef<str>>(&mut self, map_string: S) -> &mut Self

Alias for -map argument.

Create one or more streams in the output file. This option has two forms for specifying the data source(s): the first selects one or more streams from some input file (specified with -i), the second takes an output from some complex filtergraph (specified with -filter_complex or -filter_complex_script).

In the first form, an output stream is created for every stream from the input file with the index input_file_id. If stream_specifier is given, only those streams that match the specifier are used (see the Stream specifiers section for the stream_specifier syntax).

A - character before the stream identifier creates a “negative” mapping. It disables matching streams from already created mappings.

A trailing ? after the stream index will allow the map to be optional: if the map matches no streams the map will be ignored instead of failing. Note the map will still fail if an invalid input file index is used; such as if the map refers to a non-existent input.

An alternative [linklabel] form will map outputs from complex filter graphs (see the -filter_complex option) to the output file. linklabel must correspond to a defined output link label in the graph.

This option may be specified multiple times, each adding more streams to the output file. Any given input stream may also be mapped any number of times as a source for different output streams, e.g. in order to use different encoding options and/or filters. The streams are created in the output in the same order in which the -map options are given on the commandline.

Using this option disables the default mappings for this output file.

Examples found in repository?
examples/sockets.rs (line 36)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
More examples
Hide additional examples
examples/named_pipes.rs (line 44)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn readrate(&mut self, speed: f32) -> &mut Self

Alias for -readrate argument.

Limit input read speed.

Its value is a floating-point positive number which represents the maximum duration of media, in seconds, that should be ingested in one second of wallclock time. Default value is zero and represents no imposed limitation on speed of ingestion. Value 1 represents real-time speed and is equivalent to -re.

Mainly used to simulate a capture device or live input stream (e.g. when reading from a file). Should not be used with a low value when input is an actual capture device or live stream as it may cause packet loss.

It is useful for when flow speed of output packets is important, such as live streaming.

Source

pub fn realtime(&mut self) -> &mut Self

Alias for -re.

Read input at native frame rate. This is equivalent to setting -readrate 1.

Examples found in repository?
examples/ffplay_preview.rs (line 15)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
Source

pub fn fps_mode<S: AsRef<str>>(&mut self, parameter: S) -> &mut Self

Alias for -fps_mode argument.

Set video sync method / framerate mode. vsync is applied to all output video streams but can be overridden for a stream by setting fps_mode. vsync is deprecated and will be removed in the future.

For compatibility reasons some of the values for vsync can be specified as numbers (shown in parentheses in the following table).

  • passthrough (0): Each frame is passed with its timestamp from the demuxer to the muxer.
  • cfr (1): Frames will be duplicated and dropped to achieve exactly the requested constant frame rate.
  • vfr (2): Frames are passed through with their timestamp or dropped so as to prevent 2 frames from having the same timestamp.
  • drop: As passthrough but destroys all timestamps, making the muxer generate fresh timestamps based on frame-rate.
  • auto (-1): Chooses between cfr and vfr depending on muxer capabilities. This is the default method.
Source

pub fn bitstream_filter_video<S: AsRef<str>>( &mut self, bitstream_filters: S, ) -> &mut Self

Alias for -bsf:v argument.

Set bitstream filters for matching streams. bitstream_filters is a comma-separated list of bitstream filters. Use the -bsfs option to get the list of bitstream filters.

See also: -bsf:s (subtitles), -bsf:a (audio), -bsf:d (data)

Source

pub fn filter_complex<S: AsRef<str>>(&mut self, filtergraph: S) -> &mut Self

Alias for -filter_complex argument.

Define a complex filtergraph, i.e. one with arbitrary number of inputs and/or outputs. For simple graphs – those with one input and one output of the same type – see the -filter options. filtergraph is a description of the filtergraph, as described in the “Filtergraph syntax” section of the ffmpeg-filters manual.

Input link labels must refer to input streams using the [file_index:stream_specifier] syntax (i.e. the same as -map uses). If stream_specifier matches multiple streams, the first one will be used. An unlabeled input will be connected to the first unused input stream of the matching type.

Output link labels are referred to with -map. Unlabeled outputs are added to the first output file.

Note that with this option it is possible to use only lavfi sources without normal input files.

Source

pub fn testsrc(&mut self) -> &mut Self

Generate a procedural test video. Equivalent to ffmpeg -f lavfi -i testsrc=duration=10. It also inherits defaults from the testsrc filter in FFmpeg: 320x240 size and 25 fps.

FFmpeg testsrc filter documentation

Examples found in repository?
examples/metadata.rs (line 6)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
More examples
Hide additional examples
examples/hello_world.rs (line 11)
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fn main() -> anyhow::Result<()> {
  // Run an FFmpeg command that generates a test video
  let iter = FfmpegCommand::new() // <- Builder API like `std::process::Command`
    .testsrc()  // <- Discoverable aliases for FFmpeg args
    .rawvideo() // <- Convenient argument presets
    .spawn()?   // <- Ordinary `std::process::Child`
    .iter()?;   // <- Blocking iterator over logs and output

  // Use a regular "for" loop to read decoded video data
  for frame in iter.filter_frames() {
    println!("frame: {}x{}", frame.width, frame.height);
    let _pixels: Vec<u8> = frame.data; // <- raw RGB pixels! 🎨
  }

  Ok(())
}
Source

pub fn rawvideo(&mut self) -> &mut Self

Preset for emitting raw decoded video frames on stdout. Equivalent to -f rawvideo -pix_fmt rgb24 -.

Examples found in repository?
examples/hello_world.rs (line 12)
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fn main() -> anyhow::Result<()> {
  // Run an FFmpeg command that generates a test video
  let iter = FfmpegCommand::new() // <- Builder API like `std::process::Command`
    .testsrc()  // <- Discoverable aliases for FFmpeg args
    .rawvideo() // <- Convenient argument presets
    .spawn()?   // <- Ordinary `std::process::Child`
    .iter()?;   // <- Blocking iterator over logs and output

  // Use a regular "for" loop to read decoded video data
  for frame in iter.filter_frames() {
    println!("frame: {}x{}", frame.width, frame.height);
    let _pixels: Vec<u8> = frame.data; // <- raw RGB pixels! 🎨
  }

  Ok(())
}
More examples
Hide additional examples
examples/h265_transcode.rs (line 26)
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fn main() {
  // Create an H265 source video as a starting point
  let input_path = "output/h265.mp4";
  if !Path::new(input_path).exists() {
    create_h265_source(input_path);
  }

  // One instance decodes H265 to raw frames
  let mut input = FfmpegCommand::new()
    .input(input_path)
    .rawvideo()
    .spawn()
    .unwrap();

  // Frames can be transformed by Iterator `.map()`.
  // This example is a no-op, with frames passed through unaltered.
  let transformed_frames = input.iter().unwrap().filter_frames();

  // You could easily add some "middleware" processing here:
  // - overlay or composite another RGB image (or even another Ffmpeg Iterator)
  // - apply a filter like blur or convolution
  // Note: some of these operations are also possible with FFmpeg's (somewhat arcane)
  // `filtergraph` API, but doing it in Rust gives you much finer-grained
  // control, debuggability, and modularity -- you can pull in any Rust crate
  // you need.

  // A second instance encodes the updated frames back to H265
  let mut output = FfmpegCommand::new()
    .args([
      "-f", "rawvideo", "-pix_fmt", "rgb24", "-s", "600x800", "-r", "30",
    ]) // note: should be possible to infer these params from the source input stream
    .input("-")
    .args(["-c:v", "libx265"])
    .args(["-y", "output/h265_overlay.mp4"])
    .spawn()
    .unwrap();

  // Connect the two instances
  let mut stdin = output.take_stdin().unwrap();
  thread::spawn(move || {
    // `for_each` blocks through the end of the iterator,
    // so we run it in another thread.
    transformed_frames.for_each(|f| {
      stdin.write_all(&f.data).ok();
    });
  });

  // On the main thread, run the output instance to completion
  output.iter().unwrap().for_each(|e| match e {
    FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
    FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
    _ => {}
  });
}
Source

pub fn pipe_stdout(&mut self) -> &mut Self

Configure the ffmpeg command to produce output on stdout.

Synchronizes two changes:

  1. Pass pipe:1 to the ffmpeg command (“output on stdout”)
  2. Set the stdout field of the inner Command to Stdio::piped()
Source

pub fn arg<S: AsRef<OsStr>>(&mut self, arg: S) -> &mut Self

Adds an argument to pass to the program.

Identical to arg in std::process::Command.

Examples found in repository?
examples/h265_transcode.rs (line 76)
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fn create_h265_source(path_str: &str) {
  println!("Creating H265 source video: {}", path_str);
  FfmpegCommand::new()
    .args("-f lavfi -i testsrc=size=600x800:rate=30:duration=15 -c:v libx265".split(' '))
    .arg(path_str)
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .for_each(|e| match e {
      FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
      FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
      _ => {}
    });
  println!("Created H265 source video: {}", path_str);
}
Source

pub fn args<I, S>(&mut self, args: I) -> &mut Self
where I: IntoIterator<Item = S>, S: AsRef<OsStr>,

Adds multiple arguments to pass to the program.

Identical to args in std::process::Command.

Examples found in repository?
examples/progress.rs (line 18)
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fn main() {
  let fps = 60;
  let duration = 10;
  let total_frames = fps * duration;
  let arg_string = format!(
    "-f lavfi -i testsrc=duration={}:size=1920x1080:rate={} -y output/test.mp4",
    duration, fps
  );
  FfmpegCommand::new()
    .args(arg_string.split(' '))
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .filter_progress()
    .for_each(|progress| println!("{}%", (progress.frame * 100) / total_frames));
}
More examples
Hide additional examples
examples/metadata.rs (line 7)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
examples/h265_transcode.rs (lines 44-46)
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fn main() {
  // Create an H265 source video as a starting point
  let input_path = "output/h265.mp4";
  if !Path::new(input_path).exists() {
    create_h265_source(input_path);
  }

  // One instance decodes H265 to raw frames
  let mut input = FfmpegCommand::new()
    .input(input_path)
    .rawvideo()
    .spawn()
    .unwrap();

  // Frames can be transformed by Iterator `.map()`.
  // This example is a no-op, with frames passed through unaltered.
  let transformed_frames = input.iter().unwrap().filter_frames();

  // You could easily add some "middleware" processing here:
  // - overlay or composite another RGB image (or even another Ffmpeg Iterator)
  // - apply a filter like blur or convolution
  // Note: some of these operations are also possible with FFmpeg's (somewhat arcane)
  // `filtergraph` API, but doing it in Rust gives you much finer-grained
  // control, debuggability, and modularity -- you can pull in any Rust crate
  // you need.

  // A second instance encodes the updated frames back to H265
  let mut output = FfmpegCommand::new()
    .args([
      "-f", "rawvideo", "-pix_fmt", "rgb24", "-s", "600x800", "-r", "30",
    ]) // note: should be possible to infer these params from the source input stream
    .input("-")
    .args(["-c:v", "libx265"])
    .args(["-y", "output/h265_overlay.mp4"])
    .spawn()
    .unwrap();

  // Connect the two instances
  let mut stdin = output.take_stdin().unwrap();
  thread::spawn(move || {
    // `for_each` blocks through the end of the iterator,
    // so we run it in another thread.
    transformed_frames.for_each(|f| {
      stdin.write_all(&f.data).ok();
    });
  });

  // On the main thread, run the output instance to completion
  output.iter().unwrap().for_each(|e| match e {
    FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
    FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
    _ => {}
  });
}

/// Create a H265 source video from scratch
fn create_h265_source(path_str: &str) {
  println!("Creating H265 source video: {}", path_str);
  FfmpegCommand::new()
    .args("-f lavfi -i testsrc=size=600x800:rate=30:duration=15 -c:v libx265".split(' '))
    .arg(path_str)
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .for_each(|e| match e {
      FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
      FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
      _ => {}
    });
  println!("Created H265 source video: {}", path_str);
}
Source

pub fn get_args(&self) -> CommandArgs<'_>

Returns an iterator of the arguments that will be passed to the program.

Identical to get_args in std::process::Command.

Source

pub fn spawn(&mut self) -> Result<FfmpegChild>

Spawn the ffmpeg command as a child process, wrapping it in a FfmpegChild interface.

Please note that if the result is not used with wait() the process is not cleaned up correctly resulting in a zombie process until your main thread exits.

Identical to spawn in std::process::Command.

Examples found in repository?
examples/progress.rs (line 19)
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fn main() {
  let fps = 60;
  let duration = 10;
  let total_frames = fps * duration;
  let arg_string = format!(
    "-f lavfi -i testsrc=duration={}:size=1920x1080:rate={} -y output/test.mp4",
    duration, fps
  );
  FfmpegCommand::new()
    .args(arg_string.split(' '))
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .filter_progress()
    .for_each(|progress| println!("{}%", (progress.frame * 100) / total_frames));
}
More examples
Hide additional examples
examples/metadata.rs (line 11)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
examples/hello_world.rs (line 13)
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fn main() -> anyhow::Result<()> {
  // Run an FFmpeg command that generates a test video
  let iter = FfmpegCommand::new() // <- Builder API like `std::process::Command`
    .testsrc()  // <- Discoverable aliases for FFmpeg args
    .rawvideo() // <- Convenient argument presets
    .spawn()?   // <- Ordinary `std::process::Child`
    .iter()?;   // <- Blocking iterator over logs and output

  // Use a regular "for" loop to read decoded video data
  for frame in iter.filter_frames() {
    println!("frame: {}x{}", frame.width, frame.height);
    let _pixels: Vec<u8> = frame.data; // <- raw RGB pixels! 🎨
  }

  Ok(())
}
examples/ffplay_preview.rs (line 21)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
examples/sockets.rs (line 49)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/h265_transcode.rs (line 27)
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fn main() {
  // Create an H265 source video as a starting point
  let input_path = "output/h265.mp4";
  if !Path::new(input_path).exists() {
    create_h265_source(input_path);
  }

  // One instance decodes H265 to raw frames
  let mut input = FfmpegCommand::new()
    .input(input_path)
    .rawvideo()
    .spawn()
    .unwrap();

  // Frames can be transformed by Iterator `.map()`.
  // This example is a no-op, with frames passed through unaltered.
  let transformed_frames = input.iter().unwrap().filter_frames();

  // You could easily add some "middleware" processing here:
  // - overlay or composite another RGB image (or even another Ffmpeg Iterator)
  // - apply a filter like blur or convolution
  // Note: some of these operations are also possible with FFmpeg's (somewhat arcane)
  // `filtergraph` API, but doing it in Rust gives you much finer-grained
  // control, debuggability, and modularity -- you can pull in any Rust crate
  // you need.

  // A second instance encodes the updated frames back to H265
  let mut output = FfmpegCommand::new()
    .args([
      "-f", "rawvideo", "-pix_fmt", "rgb24", "-s", "600x800", "-r", "30",
    ]) // note: should be possible to infer these params from the source input stream
    .input("-")
    .args(["-c:v", "libx265"])
    .args(["-y", "output/h265_overlay.mp4"])
    .spawn()
    .unwrap();

  // Connect the two instances
  let mut stdin = output.take_stdin().unwrap();
  thread::spawn(move || {
    // `for_each` blocks through the end of the iterator,
    // so we run it in another thread.
    transformed_frames.for_each(|f| {
      stdin.write_all(&f.data).ok();
    });
  });

  // On the main thread, run the output instance to completion
  output.iter().unwrap().for_each(|e| match e {
    FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
    FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
    _ => {}
  });
}

/// Create a H265 source video from scratch
fn create_h265_source(path_str: &str) {
  println!("Creating H265 source video: {}", path_str);
  FfmpegCommand::new()
    .args("-f lavfi -i testsrc=size=600x800:rate=30:duration=15 -c:v libx265".split(' '))
    .arg(path_str)
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .for_each(|e| match e {
      FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
      FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
      _ => {}
    });
  println!("Created H265 source video: {}", path_str);
}
Source

pub fn print_command(&mut self) -> &mut Self

Print a command that can be copy-pasted to run in the terminal. Requires &mut self so that it chains seamlessly with other methods in the interface. Sample output:

ffmpeg \
  -f lavfi \
  -i testsrc=duration=10 output/test.mp4
Examples found in repository?
examples/metadata.rs (line 10)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
More examples
Hide additional examples
examples/sockets.rs (line 48)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/named_pipes.rs (line 137)
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fn main() -> anyhow::Result<()> {
  use anyhow::Result;
  use ffmpeg_sidecar::command::FfmpegCommand;
  use ffmpeg_sidecar::event::{FfmpegEvent, LogLevel};
  use ffmpeg_sidecar::named_pipes::NamedPipe;
  use ffmpeg_sidecar::pipe_name;
  use std::io::Read;
  use std::sync::mpsc;
  use std::thread;

  const VIDEO_PIPE_NAME: &str = pipe_name!("ffmpeg_video");
  const AUDIO_PIPE_NAME: &str = pipe_name!("ffmpeg_audio");
  const SUBTITLES_PIPE_NAME: &str = pipe_name!("ffmpeg_subtitles");

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  let mut command = FfmpegCommand::new();
  command
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(VIDEO_PIPE_NAME)
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(AUDIO_PIPE_NAME)
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(SUBTITLES_PIPE_NAME);

  // Create a separate thread for each output pipe
  let threads = [VIDEO_PIPE_NAME, AUDIO_PIPE_NAME, SUBTITLES_PIPE_NAME]
    .iter()
    .cloned()
    .map(|pipe_name| {
      // It's important to create the named pipe on the main thread before
      // sending it elsewhere so that any errors are caught at the top level.
      let mut pipe = NamedPipe::new(pipe_name)?;
      println!("[{pipe_name}] pipe created");
      let (ready_sender, ready_receiver) = mpsc::channel::<()>();
      let thread = thread::spawn(move || -> Result<()> {
        // Wait for FFmpeg to start writing
        // Only needed for Windows, since Unix will block until a writer has connected
        println!("[{pipe_name}] waiting for ready signal");
        ready_receiver.recv()?;

        // Read continuously until finished
        // Note that if the stream of output is interrupted or paused,
        // you may need additional logic to keep the read loop alive.
        println!("[{pipe_name}] reading from pipe");
        let mut buf = vec![0; 1920 * 1080 * 3];
        let mut total_bytes_read = 0;

        // In the case of subtitles, we'll decode the string contents directly
        let mut text_content = if pipe_name == SUBTITLES_PIPE_NAME {
          Some("".to_string())
        } else {
          None
        };

        loop {
          match pipe.read(&mut buf) {
            Ok(bytes_read) => {
              total_bytes_read += bytes_read;

              // read bytes into string
              if let Some(cur_str) = &mut text_content {
                let s = std::str::from_utf8(&buf[..bytes_read]).unwrap();
                text_content = Some(format!("{}{}", cur_str, s));
              }

              if bytes_read == 0 {
                break;
              }
            }
            Err(err) => {
              if err.kind() != std::io::ErrorKind::BrokenPipe {
                return Err(err.into());
              } else {
                break;
              }
            }
          }
        }

        // Log how many bytes were received over this pipe.
        // You can visually compare this to the FFmpeg log output to confirm
        // that all the expected bytes were captured.
        let size_str = if total_bytes_read < 1024 {
          format!("{}B", total_bytes_read)
        } else {
          format!("{}KiB", total_bytes_read / 1024)
        };

        if let Some(text_content) = text_content {
          println!("[{pipe_name}] subtitle text content: ");
          println!("{}", text_content.trim());
        }

        println!("[{pipe_name}] done reading ({size_str} total)");
        Ok(())
      });

      Ok((thread, ready_sender))
    })
    .collect::<Result<Vec<_>>>()?;

  // Start FFmpeg
  let mut ready_signal_sent = false;
  command
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Signal threads when output is ready
      FfmpegEvent::Progress(_) if !ready_signal_sent => {
        threads.iter().for_each(|(_, sender)| {
          sender.send(()).ok();
        });
        ready_signal_sent = true;
      }

      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      _ => {}
    });

  for (thread, _) in threads {
    thread.join().unwrap()?;
  }

  Ok(())
}
Source

pub fn create_no_window(&mut self) -> &mut Self

Disable creating a new console window for the spawned process on Windows. Has no effect on other platforms. This can be useful when spawning a command from a GUI program.

This is called automatically in the constructor. To override, use CommandExt::creation_flags() directly on the inner Command.

Source

pub fn new() -> Self

Examples found in repository?
examples/progress.rs (line 17)
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fn main() {
  let fps = 60;
  let duration = 10;
  let total_frames = fps * duration;
  let arg_string = format!(
    "-f lavfi -i testsrc=duration={}:size=1920x1080:rate={} -y output/test.mp4",
    duration, fps
  );
  FfmpegCommand::new()
    .args(arg_string.split(' '))
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .filter_progress()
    .for_each(|progress| println!("{}%", (progress.frame * 100) / total_frames));
}
More examples
Hide additional examples
examples/metadata.rs (line 5)
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fn main() {
  let mut ffmpeg_runner = FfmpegCommand::new()
    .testsrc()
    .args(["-metadata", "title=some cool title"])
    .overwrite() // -y
    .output("output/metadata.mp4")
    .print_command()
    .spawn()
    .unwrap();

  ffmpeg_runner
    .iter()
    .unwrap()
    .for_each(|e| {
      match e {
        FfmpegEvent::Progress(FfmpegProgress { frame, .. }) =>
          println!("Current frame: {frame}"),
        FfmpegEvent::Log(_level, msg) =>
          println!("[ffmpeg] {msg}"),
        _ => {}
      }
    });
}
examples/hello_world.rs (line 10)
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fn main() -> anyhow::Result<()> {
  // Run an FFmpeg command that generates a test video
  let iter = FfmpegCommand::new() // <- Builder API like `std::process::Command`
    .testsrc()  // <- Discoverable aliases for FFmpeg args
    .rawvideo() // <- Convenient argument presets
    .spawn()?   // <- Ordinary `std::process::Child`
    .iter()?;   // <- Blocking iterator over logs and output

  // Use a regular "for" loop to read decoded video data
  for frame in iter.filter_frames() {
    println!("frame: {}x{}", frame.width, frame.height);
    let _pixels: Vec<u8> = frame.data; // <- raw RGB pixels! 🎨
  }

  Ok(())
}
examples/ffplay_preview.rs (line 14)
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fn main() {
  let mut ffmpeg = FfmpegCommand::new()
    .realtime()
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60")
    .codec_video("rawvideo")
    .format("avi")
    .output("-")
    .spawn()
    .unwrap();

  let mut ffplay = Command::new("ffplay")
    .args("-i -".split(' '))
    .stdin(Stdio::piped())
    .spawn()
    .unwrap();

  let mut ffmpeg_stdout = ffmpeg.take_stdout().unwrap();
  let mut ffplay_stdin = ffplay.stdin.take().unwrap();

  // pipe from ffmpeg stdout to ffplay stdin
  let buf = &mut [0u8; 4096];
  loop {
    let n = ffmpeg_stdout.read(buf).unwrap();
    if n == 0 {
      break;
    }
    ffplay_stdin.write_all(&buf[..n]).unwrap();
  }
}
examples/sockets.rs (line 20)
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fn main() -> Result<()> {
  // Set up a TCP listener
  const TCP_PORT: u32 = 3000;
  let (exit_sender, exit_receiver) = channel::<()>();
  let listener_thread = thread::spawn(|| listen_for_connections(TCP_PORT, exit_receiver));

  // Wait for the listener to start
  thread::sleep(Duration::from_millis(1000));

  // Prepare an FFmpeg command with separate outputs for video, audio, and subtitles.
  FfmpegCommand::new()
    // Global flags
    .hide_banner()
    .overwrite() // <- overwrite required on windows
    // Generate test video
    .format("lavfi")
    .input("testsrc=size=1920x1080:rate=60:duration=10")
    // Generate test audio
    .format("lavfi")
    .input("sine=frequency=1000:duration=10")
    // Generate test subtitles
    .format("srt")
    .input(
      "data:text/plain;base64,MQ0KMDA6MDA6MDAsMDAwIC0tPiAwMDowMDoxMCw1MDANCkhlbGxvIFdvcmxkIQ==",
    )
    // Video output
    .map("0:v")
    .format("rawvideo")
    .pix_fmt("rgb24")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Audio output
    .map("1:a")
    .format("s16le")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    // Subtitles output
    .map("2:s")
    .format("srt")
    .output(format!("tcp://127.0.0.1:{TCP_PORT}"))
    .print_command()
    .spawn()?
    .iter()?
    .for_each(|event| match event {
      // Verify output size from FFmpeg logs (video/audio KiB)
      FfmpegEvent::Log(LogLevel::Info, msg) if msg.starts_with("[out#") => {
        println!("{msg}");
      }

      // Log any unexpected errors
      FfmpegEvent::Log(LogLevel::Warning | LogLevel::Error | LogLevel::Fatal, msg) => {
        eprintln!("{msg}");
      }

      // _ => {}
      e => {
        println!("{:?}", e);
      }
    });
  exit_sender.send(())?;
  listener_thread.join().unwrap()?;
  Ok(())
}
examples/h265_transcode.rs (line 24)
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fn main() {
  // Create an H265 source video as a starting point
  let input_path = "output/h265.mp4";
  if !Path::new(input_path).exists() {
    create_h265_source(input_path);
  }

  // One instance decodes H265 to raw frames
  let mut input = FfmpegCommand::new()
    .input(input_path)
    .rawvideo()
    .spawn()
    .unwrap();

  // Frames can be transformed by Iterator `.map()`.
  // This example is a no-op, with frames passed through unaltered.
  let transformed_frames = input.iter().unwrap().filter_frames();

  // You could easily add some "middleware" processing here:
  // - overlay or composite another RGB image (or even another Ffmpeg Iterator)
  // - apply a filter like blur or convolution
  // Note: some of these operations are also possible with FFmpeg's (somewhat arcane)
  // `filtergraph` API, but doing it in Rust gives you much finer-grained
  // control, debuggability, and modularity -- you can pull in any Rust crate
  // you need.

  // A second instance encodes the updated frames back to H265
  let mut output = FfmpegCommand::new()
    .args([
      "-f", "rawvideo", "-pix_fmt", "rgb24", "-s", "600x800", "-r", "30",
    ]) // note: should be possible to infer these params from the source input stream
    .input("-")
    .args(["-c:v", "libx265"])
    .args(["-y", "output/h265_overlay.mp4"])
    .spawn()
    .unwrap();

  // Connect the two instances
  let mut stdin = output.take_stdin().unwrap();
  thread::spawn(move || {
    // `for_each` blocks through the end of the iterator,
    // so we run it in another thread.
    transformed_frames.for_each(|f| {
      stdin.write_all(&f.data).ok();
    });
  });

  // On the main thread, run the output instance to completion
  output.iter().unwrap().for_each(|e| match e {
    FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
    FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
    _ => {}
  });
}

/// Create a H265 source video from scratch
fn create_h265_source(path_str: &str) {
  println!("Creating H265 source video: {}", path_str);
  FfmpegCommand::new()
    .args("-f lavfi -i testsrc=size=600x800:rate=30:duration=15 -c:v libx265".split(' '))
    .arg(path_str)
    .spawn()
    .unwrap()
    .iter()
    .unwrap()
    .for_each(|e| match e {
      FfmpegEvent::Log(LogLevel::Error, e) => println!("Error: {}", e),
      FfmpegEvent::Progress(p) => println!("Progress: {} / 00:00:15", p.time),
      _ => {}
    });
  println!("Created H265 source video: {}", path_str);
}
Source

pub fn new_with_path<S: AsRef<OsStr>>(path_to_ffmpeg_binary: S) -> Self

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pub fn as_inner(&mut self) -> &Command

Escape hatch to access the inner Command.

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pub fn as_inner_mut(&mut self) -> &mut Command

Escape hatch to mutably access the inner Command.

Trait Implementations§

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impl Debug for FfmpegCommand

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Format the program and arguments of a Command for display. Any non-utf8 data is lossily converted using the utf8 replacement character.

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impl Default for FfmpegCommand

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fn default() -> Self

Returns the “default value” for a type. Read more
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impl From<Command> for FfmpegCommand

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fn from(inner: Command) -> Self

Convert a Command into a FfmpegCommand, making no guarantees about the validity of its configured arguments and stdio. For example, set_expected_loglevel() is not automatically applied, which can have unexpected effects on log parsing.

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impl From<FfmpegCommand> for Command

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fn from(val: FfmpegCommand) -> Self

Converts to this type from the input type.

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where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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where U: Into<T>,

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type Error = Infallible

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Performs the conversion.
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where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

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