Crate libwebp

Expand description

libwebp

This is a binding to the libwebp library.

Usage

Preparation

# Cargo.toml

[dependencies]
libwebp = { version = "0.1.2", features = ["0_6"] }

Simple decoding

You can use WebPDecodeRGBA or WebPDecodeRGBAInto families for simple decoding.

use libwebp::WebPDecodeRGBA;

let data: &[u8];

let (width, height, buf) = WebPDecodeRGBA(data).unwrap();
assert_eq!(buf.len(), width as usize * height as usize * 4);
eprintln!("width = {}, height = {}", width, height);
eprintln!(
    "top-left pixel: rgba({}, {}, {}, {})",
    buf[0],
    buf[1],
    buf[2],
    buf[3] as f64 / 255.0,
)

Simple encoding

You can use WebPEncodeRGBA or WebPEncodeLosslessRGBA families for simple encoding.

use libwebp::{WebPEncodeRGBA, WebPEncodeLosslessRGBA};

let buf: &[u8] = &[
    255, 255, 255, 255, // white
    255, 0, 0, 255, // red
    0, 255, 0, 255, // green
    0, 0, 255, 255, // blue
];
let data = WebPEncodeRGBA(buf, 2, 2, 8, 75.0).unwrap();
let lossless_data = WebPEncodeLosslessRGBA(buf, 2, 2, 8).unwrap();
assert_eq!(&data[..4], b"RIFF");
assert_eq!(&data[8..12], b"WEBP");
assert_eq!(&lossless_data[..4], b"RIFF");
assert_eq!(&lossless_data[8..12], b"WEBP");

Modules

Safe RAII wrappers for WebPFree.

Error type definitions.

Structs

WebPIDecGetRGBResult

WebPIDecGetYUVAResult

Enums

Functions

Same as WebPDecodeRGBA, but returning A, R, G, B, A, R, G, B… ordered data.

WebPDecodeARGBInto

Same as WebPDecodeRGBAInto, but returning A, R, G, B, A, R, G, B… ordered data.

Same as WebPDecodeRGBA, but returning B, G, R, B, G, R… ordered data.

Same as WebPDecodeRGBA, but returning B, G, R, A, B, G, R, A… ordered data.

WebPDecodeBGRAInto

Same as WebPDecodeRGBAInto, but returning B, G, R, A, B, G, R, A… ordered data.

WebPDecodeBGRInto

Same as WebPDecodeRGBAInto, but returning B, G, R, B, G, R… ordered data.

Same as WebPDecodeRGBA, but returning R, G, B, R, G, B… ordered data.

Decodes WebP images pointed to by data and returns RGBA samples, along with the dimensions (width and height).

WebPDecodeRGBAInto

Decodes WebP images pointed to by data and writes RGBA samples to output_buffer.

WebPDecodeRGBInto

Same as WebPDecodeRGBAInto, but returning R, G, B, R, G, B… ordered data.

Decodes WebP images pointed to by data to Y’UV format¹.

WebPDecodeYUVInto

A variant of WebPDecodeYUVInto that operates directly into pre-allocated buffers.

Same as WebPEncodeRGBA, but expecting B, G, R, B, G, R… ordered data.

Same as WebPEncodeRGBA, but expecting B, G, R, A, B, G, R, A… ordered data.

WebPEncodeLosslessBGR

Same as WebPEncodeLosslessRGBA, but expecting B, G, R, B, G, R… ordered data.

WebPEncodeLosslessBGRA

Same as WebPEncodeLosslessRGBA, but expecting B, G, R, A, B, G, R, A… ordered data.

WebPEncodeLosslessRGB

Same as WebPEncodeLosslessRGBA, but expecting R, G, B, R, G, B… ordered data.

WebPEncodeLosslessRGBA

Encodes images pointed to by rgba and returns the WebP binary data.

Same as WebPEncodeRGBA, but expecting R, G, B, R, G, B… ordered data.

Encodes images pointed to by rgba and returns the WebP binary data.

WebPGetDecoderVersion

Return the decoder’s version number, packed in hexadecimal using 8bits for each of major/minor/revision.

WebPGetEncoderVersion

Return the encoder’s version number, packed in hexadecimal using 8bits for each of major/minor/revision.

Retrieve basic header information: width, height.

WebPIDecGetYUVA

WebPINewDecoder

WebPIsAlphaMode

WebPIsPremultipliedMode