GIF libraries for Java

• ImageIO (javax.imageio) reads and writes GIF, including animated GIF, with no dependencies. Frames, delays, disposal and the Netscape loop block are accessed through the javax_imageio_gif_image_1.0 metadata tree, which is verbose but complete. It returns raw frames (not composited) and quantizes RGB images itself when writing.

Higher-level wrappers exist but are small, mostly unmaintained projects; most Java code uses ImageIO directly, or calls ImageMagick or FFmpeg for heavy GIF work.

• ImageIO Java ImageIO reads and writes GIF and animated GIF with no dependencies. How to read all frames with their delays and positions.