Struct WebPConfig

#[repr(C)]
pub struct WebPConfig {

    pub lossless: c_int,
    pub quality: c_float,
    pub method: c_int,
    pub image_hint: WebPImageHint,
    pub target_size: c_int,
    pub target_PSNR: c_float,
    pub segments: c_int,
    pub sns_strength: c_int,
    pub filter_strength: c_int,
    pub filter_sharpness: c_int,
    pub filter_type: c_int,
    pub autofilter: c_int,
    pub alpha_compression: c_int,
    pub alpha_filtering: c_int,
    pub alpha_quality: c_int,
    pub pass: c_int,
    pub show_compressed: c_int,
    pub preprocessing: c_int,
    pub partitions: c_int,
    pub partition_limit: c_int,
    pub emulate_jpeg_size: c_int,
    pub thread_level: c_int,
    pub low_memory: c_int,
    pub near_lossless: c_int,
    pub exact: c_int,
    pub use_delta_palette: c_int,
    pub use_sharp_yuv: c_int,
    pub qmin: c_int,
    pub qmax: c_int,
}

Compression parameters.

Fields

lossless: c_int

Lossless encoding (0=lossy(default), 1=lossless).

quality: c_float

between 0 and 100. For lossy, 0 gives the smallest size and 100 the largest. For lossless, this parameter is the amount of effort put into the compression: 0 is the fastest but gives larger files compared to the slowest, but best, 100.

method: c_int

quality/speed trade-off (0=fast, 6=slower-better)

image_hint: WebPImageHint

Hint for image type (lossless only for now).

target_size: c_int

if non-zero, set the desired target size in bytes. Takes precedence over the compression parameter.

target_PSNR: c_float

if non-zero, specifies the minimal distortion to try to achieve. Takes precedence over target_size.

segments: c_int

maximum number of segments to use, in [1..4]

sns_strength: c_int

Spatial Noise Shaping. 0=off, 100=maximum.

filter_strength: c_int

range: [0 = off .. 100 = strongest]

filter_sharpness: c_int

range: [0 = off .. 7 = least sharp]

filter_type: c_int

filtering type: 0 = simple, 1 = strong (only used if filter_strength > 0 or autofilter > 0)

autofilter: c_int

Auto adjust filter’s strength [0 = off, 1 = on]

alpha_compression: c_int

Algorithm for encoding the alpha plane (0 = none, 1 = compressed with WebP lossless). Default is 1.

alpha_filtering: c_int

Predictive filtering method for alpha plane. 0: none, 1: fast, 2: best. Default if 1.

alpha_quality: c_int

Between 0 (smallest size) and 100 (lossless). Default is 100.

pass: c_int

number of entropy-analysis passes (in [1..10]).

show_compressed: c_int

if true, export the compressed picture back. In-loop filtering is not applied.

preprocessing: c_int

preprocessing filter: 0=none, 1=segment-smooth, 2=pseudo-random dithering

partitions: c_int

log2(number of token partitions) in [0..3]. Default is set to 0 for easier progressive decoding.

partition_limit: c_int

quality degradation allowed to fit the 512k limit on prediction modes coding (0: no degradation, 100: maximum possible degradation).

emulate_jpeg_size: c_int

If true, compression parameters will be remapped to better match the expected output size from JPEG compression. Generally, the output size will be similar but the degradation will be lower.

thread_level: c_int

If non-zero, try and use multi-threaded encoding.

low_memory: c_int

If set, reduce memory usage (but increase CPU use).

near_lossless: c_int

Available on crate feature 0_5 only.

Near lossless encoding [0 = max loss .. 100 = off (default)].

exact: c_int

Available on crate feature 0_5 only.

if non-zero, preserve the exact RGB values under transparent area. Otherwise, discard this invisible RGB information for better compression. The default value is 0.

use_delta_palette: c_int

Available on crate feature 0_6 only.

reserved

use_sharp_yuv: c_int

Available on crate feature 0_6 only.

if needed, use sharp (and slow) RGB->YUV conversion

qmin: c_int

Available on crate feature 1_2 only.

minimum permissible quality factor

qmax: c_int

Available on crate feature 1_2 only.

maximum permissible quality factor

Trait Implementations

impl Clone for WebPConfig

fn clone(&self) -> WebPConfig

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WebPConfig

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

Formats the value using the given formatter.

impl Copy for WebPConfig