node_modules/@jimp/js-gif/src/index.ts

import GIF from "omggif";
import { GifUtil, GifFrame, BitmapImage, GifCodec } from "gifwrap";
import { Format } from "@jimp/types";

export interface JPEGOptions {
  quality?: number;
}

export default function gif() {
  return {
    mime: "image/gif",
    encode: async (bitmap) => {
      const gif = new BitmapImage(bitmap);
      GifUtil.quantizeDekker(gif, 256);
      const newFrame = new GifFrame(bitmap);
      const gifCodec = new GifCodec();
      const newGif = await gifCodec.encodeGif([newFrame], {});
      return newGif.buffer;
    },
    decode: (data) => {
      const gifObj = new GIF.GifReader(data);
      const gifData = Buffer.alloc(gifObj.width * gifObj.height * 4);

      gifObj.decodeAndBlitFrameRGBA(0, gifData);

      return {
        data: gifData,
        width: gifObj.width,
        height: gifObj.height,
      };
    },
  } satisfies Format<"image/gif">;
}