From 396c09c24d3ff066c5e819c3b270ff6ede6ea301 Mon Sep 17 00:00:00 2001
From: Hajime-san <41257923+Hajime-san@users.noreply.github.com>
Date: Fri, 30 Aug 2024 14:00:05 +0900
Subject: [PATCH] support animated GIF

---
 ext/canvas/lib.rs                        |  14 +-------------
 tests/testdata/image/1x1-3f-animated.gif | Bin 0 -> 126 bytes
 tests/unit/image_bitmap_test.ts          |  13 +++++++++++++
 3 files changed, 14 insertions(+), 13 deletions(-)
 create mode 100644 tests/testdata/image/1x1-3f-animated.gif

diff --git a/ext/canvas/lib.rs b/ext/canvas/lib.rs
index 66a6c06e94..0c42c7efbf 100644
--- a/ext/canvas/lib.rs
+++ b/ext/canvas/lib.rs
@@ -14,7 +14,6 @@ use image::codecs::png::PngDecoder;
 use image::codecs::webp::WebPDecoder;
 use image::imageops::overlay;
 use image::imageops::FilterType;
-use image::AnimationDecoder;
 use image::ColorType;
 use image::DynamicImage;
 use image::GenericImageView;
@@ -391,6 +390,7 @@ macro_rules! impl_image_decoder_from_reader {
 // If PngDecoder decodes an animated image, it returns the default image if one is set, or the first frame if not.
 impl_image_decoder_from_reader!(PngDecoder<R>, ImageDecoderFromReaderType);
 impl_image_decoder_from_reader!(JpegDecoder<R>, ImageDecoderFromReaderType);
+// The GifDecoder decodes the first frame.
 impl_image_decoder_from_reader!(GifDecoder<R>, ImageDecoderFromReaderType);
 impl_image_decoder_from_reader!(BmpDecoder<R>, ImageDecoderFromReaderType);
 impl_image_decoder_from_reader!(IcoDecoder<R>, ImageDecoderFromReaderType);
@@ -423,18 +423,6 @@ fn decode_bitmap_data(
           decoder.to_intermediate_image()?
         }
         "image/gif" => {
-          let decoder: GifDecoder<ImageDecoderFromReaderType> =
-            ImageDecoderFromReader::to_decoder(BufReader::new(Cursor::new(
-              buf,
-            )))?;
-          if decoder.into_frames().count() > 1 {
-            return Err(
-              DOMExceptionInvalidStateError::new(
-                "Animation image is not supported.",
-              )
-              .into(),
-            );
-          }
           let decoder: GifDecoder<ImageDecoderFromReaderType> =
             ImageDecoderFromReader::to_decoder(BufReader::new(Cursor::new(
               buf,
diff --git a/tests/testdata/image/1x1-3f-animated.gif b/tests/testdata/image/1x1-3f-animated.gif
new file mode 100644
index 0000000000000000000000000000000000000000..08d3cbc4008a209cce25d1e76f6f49faecb7c883
GIT binary patch
literal 126
zcmZ?wbhEHbWMp7uXkdT>#sA!Xt|7tBjsdPldIrplKw-t7EG$MqS_h;AtoT2O#lXbm
S!iYtZ0W6D45-barv<3ipl@L|{

literal 0
HcmV?d00001

diff --git a/tests/unit/image_bitmap_test.ts b/tests/unit/image_bitmap_test.ts
index 118ad775ad..fb3ecf9595 100644
--- a/tests/unit/image_bitmap_test.ts
+++ b/tests/unit/image_bitmap_test.ts
@@ -346,4 +346,17 @@ Deno.test(async function imageBitmapFromBlobAnimatedImage() {
     // deno-fmt-ignore
     assertEquals(Deno[Deno.internal].getBitmapData(imageBitmap), new Uint8Array([255, 0, 0, 127]));
   }
+  {
+    // the chunk of animated gif is below (3 frames, 1x1, 8-bit, RGBA)
+    // [ 255, 0, 0, 255,
+    //   0, 255, 0, 255,
+    //   0, 0, 255, 255 ]
+    const imageData = new Blob([
+      await Deno.readFile(`${prefix}/1x1-3f-animated.gif`),
+    ], { type: "image/gif" });
+    const imageBitmap = await createImageBitmap(imageData);
+    // @ts-ignore: Deno[Deno.internal].core allowed
+    // deno-fmt-ignore
+    assertEquals(Deno[Deno.internal].getBitmapData(imageBitmap), new Uint8Array([255, 0, 0, 255]));
+  }
 });