Struct Encoder 

pub struct Encoder { /* private fields */ }

JPEG encoder.

Implementations

impl Encoder

pub fn new() -> Self

Creates a new encoder with default settings.

pub fn from_config(config: EncoderConfig) -> Self

Creates an encoder from configuration.

pub fn width(self, width: u32) -> Self

Sets the image width.

pub fn height(self, height: u32) -> Self

Sets the image height.

pub fn pixel_format(self, format: PixelFormat) -> Self

Sets the pixel format.

pub fn quality(self, quality: Quality) -> Self

Sets the quality.

pub fn mode(self, mode: JpegMode) -> Self

Sets the encoding mode.

pub fn subsampling(self, subsampling: Subsampling) -> Self

Sets chroma subsampling.

pub fn use_xyb(self, enable: bool) -> Self

Enables XYB-optimized encoding mode.

XYB mode encodes images using the perceptually-optimized XYB color space from JPEG XL. This provides better quality at the same file size compared to standard YCbCr encoding.

The implementation includes:

1. Full sRGB → linear RGB → XYB color space conversion
2. XYB value scaling for optimal quantization
3. Embedded ICC profile for decoder color interpretation
4. Blue channel subsampling (R:2×2, G:2×2, B:1×1)
5. Separate XYB-optimized quant tables per component

The ICC profile allows any ICC-aware decoder (including djpegli, ImageMagick, and most image viewers) to correctly interpret the XYB values back to sRGB.

Note: Without ICC profile support in the decoder, images will display with incorrect colors. Use standard YCbCr mode for maximum compatibility.

pub fn restart_interval(self, interval: u16) -> Self

Sets the restart interval.

pub fn optimize_huffman(self, enable: bool) -> Self

Enables optimized Huffman tables.

pub fn encode(&self, data: &[u8]) -> Result<Vec<u8>>

Encodes the image data.

Trait Implementations

impl Default for Encoder

fn default() -> Self

Returns the “default value” for a type.