From 7d33b933107bb3fc9900cd9084ee839c45c70885 Mon Sep 17 00:00:00 2001
From: zk-phi <zk-phi@users.noreply.github.com>
Date: Sat, 22 Jun 2024 22:05:55 +0900
Subject: [PATCH] Use rgba4444 format for transparent animated GIFs

---
 src/gifworker.ts | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/gifworker.ts b/src/gifworker.ts
index 53c4b567..af89b0bd 100644
--- a/src/gifworker.ts
+++ b/src/gifworker.ts
@@ -8,8 +8,9 @@ const encoder = GIFEncoder();
 ctx.addEventListener("message", (msg) => {
   if (msg.data.addFrame) {
     const { data, transparent, width, height, delay } = msg.data.addFrame;
-    const palette = quantize(data, 256, { oneBitAlpha: transparent });
-    const index = applyPalette(data, palette);
+    const format = transparent ? "rgba4444" : "rgb565";
+    const palette = quantize(data, 256, { format, oneBitAlpha: transparent });
+    const index = applyPalette(data, palette, format);
     encoder.writeFrame(index, width, height, { palette, delay, transparent });
   } else if (msg.data.finish) {
     encoder.finish();