Crate gif

GIF en- and decoding library

GIF en- and decoder written in Rust (API Documentation).

GIF encoding and decoding library

This library provides all functions necessary to de- and encode GIF files.

High level interface

The high level interface consists of the two types Encoder and Decoder.

Decoding GIF files

// Open the file
use std::fs::File;
let mut decoder = gif::DecodeOptions::new();
// Configure the decoder such that it will expand the image to RGBA.
decoder.set_color_output(gif::ColorOutput::RGBA);
// Read the file header
let file = File::open("tests/samples/sample_1.gif").unwrap();
let mut decoder = decoder.read_info(file).unwrap();
while let Some(frame) = decoder.read_next_frame().unwrap() {
    // Process every frame
}

Encoding GIF files

The encoder can be used so save simple computer generated images:

use gif::{Frame, Encoder, Repeat};
use std::fs::File;
use std::borrow::Cow;
 
let color_map = &[0xFF, 0xFF, 0xFF, 0, 0, 0];
let (width, height) = (6, 6);
let mut beacon_states = [[
    0, 0, 0, 0, 0, 0,
    0, 1, 1, 0, 0, 0,
    0, 1, 1, 0, 0, 0,
    0, 0, 0, 1, 1, 0,
    0, 0, 0, 1, 1, 0,
    0, 0, 0, 0, 0, 0,
], [
    0, 0, 0, 0, 0, 0,
    0, 1, 1, 0, 0, 0,
    0, 1, 0, 0, 0, 0,
    0, 0, 0, 0, 1, 0,
    0, 0, 0, 1, 1, 0,
    0, 0, 0, 0, 0, 0,
]];
let mut image = File::create("tests/samples/beacon.gif").unwrap();;
let mut encoder = Encoder::new(&mut image, width, height, color_map).unwrap();
encoder.set_repeat(Repeat::Infinite).unwrap();
for state in &beacon_states {
    let mut frame = Frame::default();
    frame.width = width;
    frame.height = height;
    frame.buffer = Cow::Borrowed(&*state);
    encoder.write_frame(&frame).unwrap();
}

Frame::from_* can be used to convert a true color image to a paletted image with a maximum of 256 colors:

use std::fs::File;
 
// Get pixel data from some source
let mut pixels: Vec<u8> = vec![0; 30_000];
// Create frame from data
let frame = gif::Frame::from_rgb(100, 100, &mut *pixels);
// Create encoder
let mut image = File::create("target/indexed_color.gif").unwrap();
let mut encoder = gif::Encoder::new(&mut image, frame.width, frame.height, &[]).unwrap();
// Write frame to file
encoder.write_frame(&frame).unwrap();

Structs

AnyExtension	A newtype wrapper around an arbitrary extension ID.
DecodeOptions	Options for opening a GIF decoder.
Decoder	GIF decoder
DecodingFormatError	An error returned in the case of the image not being formatted properly.
Encoder	GIF encoder.
Frame	A GIF frame
MemoryLimit	Memory limit in bytes. MemoryLimit::Some(0) means that there is no memory limit set.
StreamingDecoder	GIF decoder which supports streaming

Enums

Block	Known GIF block labels.
ColorOutput	Output mode for the image data
Decoded	Indicates whether a certain object has been decoded
DecodingError	Decoding error.
DisposalMethod	Disposal method
EncodingError	Encoding error.
Extension	Known GIF extension labels.
ExtensionData	Extension data.
Extensions	Configures how extensions should be handled
Repeat	Number of repetitions