Struct DateTime

pub struct DateTime {
    pub year: u16,
    pub month: u8,
    pub day: u8,
    pub hour: u8,
    pub minute: u8,
    pub second: u8,
    pub nanosecond: Option<u32>,
    pub offset: Option<i16>,
}

A struct used to parse a DateTime field.

Examples

use exif::DateTime;
let dt = DateTime::from_ascii(b"2016:05:04 03:02:01")?;
assert_eq!(dt.year, 2016);
assert_eq!(dt.to_string(), "2016-05-04 03:02:01");

Fields

year: u16

month: u8

day: u8

hour: u8

minute: u8

second: u8

nanosecond: Option<u32>

The subsecond data in nanoseconds. If the Exif attribute has more sigfinicant digits, they are rounded down.

offset: Option<i16>

The offset of the time zone in minutes.

Implementations

impl DateTime

pub fn from_ascii(data: &[u8]) -> Result<DateTime, Error>

Parse an ASCII data of a DateTime field. The range of a number is not validated, so, for example, 13 may be returned as the month.

If the value is blank, Error::BlankValue is returned.

Examples found in repository

examples/reading.rs (line 76)

fn main() {
    let file = File::open("tests/exif.jpg").unwrap();
    let exif = Reader::new().read_from_container(
        &mut BufReader::new(&file)).unwrap();

    // To obtain a string representation, `Value::display_as`
    // or `Field::display_value` can be used.  To display a value with its
    // unit, call `with_unit` on the return value of `Field::display_value`.
    let tag_list = [Tag::ExifVersion,
                    Tag::PixelXDimension,
                    Tag::XResolution,
                    Tag::ImageDescription,
                    Tag::DateTime];
    for tag in tag_list {
        if let Some(field) = exif.get_field(tag, In::PRIMARY) {
            println!("{}: {}",
                     field.tag, field.display_value().with_unit(&exif));
        }
    }

    // To get unsigned integer value(s) from either of BYTE, SHORT,
    // or LONG, `Value::get_uint` or `Value::iter_uint` can be used.
    if let Some(field) = exif.get_field(Tag::PixelXDimension, In::PRIMARY) {
        if let Some(width) = field.value.get_uint(0) {
            println!("Valid width of the image is {}.", width);
        }
    }

    // To convert a Rational or SRational to an f64, `Rational::to_f64`
    // or `SRational::to_f64` can be used.
    if let Some(field) = exif.get_field(Tag::XResolution, In::PRIMARY) {
        match field.value {
            Value::Rational(ref vec) if !vec.is_empty() =>
                println!("X resolution is {}.", vec[0].to_f64()),
            _ => {},
        }
    }

    // To parse a DateTime-like field, `DateTime::from_ascii` can be used.
    if let Some(field) = exif.get_field(Tag::DateTime, In::PRIMARY) {
        match field.value {
            Value::Ascii(ref vec) if !vec.is_empty() => {
                if let Ok(datetime) = DateTime::from_ascii(&vec[0]) {
                    println!("Year of DateTime is {}.", datetime.year);
                }
            },
            _ => {},
        }
    }
}

pub fn parse_subsec(&mut self, data: &[u8]) -> Result<(), Error>

Parses an SubsecTime-like field.

pub fn parse_offset(&mut self, data: &[u8]) -> Result<(), Error>

Parses an OffsetTime-like field.

Trait Implementations

impl Debug for DateTime

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

Formats the value using the given formatter.

impl Display for DateTime

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

Formats the value using the given formatter.