A pure Java library implementing the GIF89a specification. Suitable for use on Android.
Java Shell

README.md

gifencoder

gifencoder is a pure Java library implementing the GIF89a specification. It does not use AWT's BufferedImage, so it can be used on Android and other platforms lacking AWT.

There is currently no support for transparency.

Quantization and dithering

GIF images are limited to 256 colors. If you supply an image with more colors, gifencoder's default behavior is to perform median-cut quantization with Floyd-Steinberg dithering. You can configure this behavior through ImageOptions. A handful of quantizers and ditherers are provided, but you can also plug in your own implementation.

Basic usage

int[][] rgbDataFrame1 = ...;
int[][] rgbDataFrame2 = ...;
int[][] rgbDataFrame3 = ...;

OutputStream outputStream = new FileOutputStream("test.gif");
ImageOptions options = new ImageOptions();
new GifEncoder(outputStream, width, height, 0)
        .addImage(rgbDataFrame1, options)
        .addImage(rgbDataFrame2, options)
        .addImage(rgbDataFrame3, options)
        .finishEncoding();
outputStream.close();

Download

Gradle:

compile 'com.squareup:gifencoder:0.9.0'

Maven:

<dependency>
  <groupId>com.squareup</groupId>
  <artifactId>gifencoder</artifactId>
  <version>0.9.0</version>
</dependency>

Or download the latest JAR.

Snapshots of the development version are available in Sonatype's snapshots repository.

Gallery

Simple animation with median-cut quantization and Floyd-Steinberg dithering:

simple animation

Lenna, original PNG:

Lenna original

Lenna with uniform quantization and Floyd-Steinberg dithering:

Lenna with uniform quantization and Floyd-Steinberg dithering

Lenna GIF with median-cut quantization and Floyd-Steinberg dithering:

Lenna with median-cut quantization and Floyd-Steinberg dithering

Lenna GIF with k-means quantization and Floyd-Steinberg dithering:

Lenna with k-means quantization and Floyd-Steinberg dithering

License

Copyright 2015 Square, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.