Struct jpegxl_rs::encode::JxlEncoder

pub struct JxlEncoder<'prl, 'mm> {
    pub has_alpha: bool,
    pub lossless: bool,
    pub speed: EncoderSpeed,
    pub quality: f32,
    pub use_container: bool,
    pub uses_original_profile: bool,
    pub decoding_speed: i64,
    pub init_buffer_size: usize,
    pub color_encoding: ColorEncoding,
    pub parallel_runner: Option<&'prl dyn JxlParallelRunner>,
    /* private fields */
}

JPEG XL Encoder

Fields

has_alpha: bool

Set alpha channel

Default: false

lossless: bool

Set lossless

Default: false

speed: EncoderSpeed

Set speed

Default: Squirrel (7).

quality: f32

Set quality for lossy compression: target max butteraugli distance, lower = higher quality

Range: 0 .. 15.
0.0 = mathematically lossless (however, use lossless to use true lossless).
1.0 = visually lossless.
Recommended range: 0.5 .. 3.0.
Default value: 1.0.
If lossless is set to true, this value is unused and implied to be 0.

use_container: bool

Configure the encoder to use the JPEG XL container format

Using the JPEG XL container format allows to store metadata such as JPEG reconstruction; but it adds a few bytes to the encoded file for container headers even if there is no extra metadata.

uses_original_profile: bool

Configure the encoder to use the original color profile

If the input image has a color profile, it will be used for the encoded image. Otherwise, an internal fixed color profile is chosen (which should be smaller).

When lossless recompressing JPEG image, you must set this to true.

Default: false

decoding_speed: i64

Set the decoding speed tier

Minimum is 0 (highest quality), and maximum is 4 (lowest quality). Default is 0.

init_buffer_size: usize

Set initial output buffer size in bytes. Anything less than 32 bytes will be rounded up to 32 bytes.

Default: 512 KiB

color_encoding: ColorEncoding

Set color encoding

Default: SRGB

parallel_runner: Option<&'prl dyn JxlParallelRunner>

Set parallel runner

Default: None, indicating single thread execution

Implementations

impl<'prl, 'mm> JxlEncoder<'prl, 'mm>

pub fn set_frame_option( &mut self, option: FrameSetting, value: i64 ) -> Result<(), EncodeError>

Set a specific encoder frame setting

Errors

Return EncodeError if it fails to set frame option

pub fn multiple<'enc, U: PixelType>( &'enc mut self, width: u32, height: u32 ) -> Result<MultiFrames<'enc, 'prl, 'mm, U>, EncodeError>

Return a wrapper type for adding multiple frames to the encoder

Errors

Return EncodeError if it fails to set up the encoder

pub fn add_metadata( &mut self, metadata: &Metadata<'_>, compress: bool ) -> Result<(), EncodeError>

Add a metadata box to the encoder

Errors

Return EncodeError if it fails to add metadata

pub fn encode_jpeg( &mut self, data: &[u8] ) -> Result<EncoderResult<u8>, EncodeError>

Encode a JPEG XL image from existing raw JPEG data

Note: Only support output pixel type of u8. Ignore alpha channel settings

Errors

Return EncodeError if the internal encoder fails to encode

pub fn encode<T: PixelType, U: PixelType>( &mut self, data: &[T], width: u32, height: u32 ) -> Result<EncoderResult<U>, EncodeError>

Encode a JPEG XL image from pixels

Note: Use RGB(3) channels, native endianness and no alignment. Ignore alpha channel settings

Errors

Return EncodeError if the internal encoder fails to encode

pub fn encode_frame<T: PixelType, U: PixelType>( &mut self, frame: &EncoderFrame<'_, T>, width: u32, height: u32 ) -> Result<EncoderResult<U>, EncodeError>

Encode a JPEG XL image from a frame. See EncoderFrame for custom options of the original pixels.

Errors

Return EncodeError if the internal encoder fails to encode

Trait Implementations

impl Drop for JxlEncoder<'_, '_>

fn drop(&mut self)

Executes the destructor for this type.