From 3163a925946f307c5cc0ed0f475724f5e7a5eddc Mon Sep 17 00:00:00 2001
From: Kornel <kornel@cloudflare.com>
Date: Fri, 15 Jan 2021 13:50:45 +0000
Subject: [PATCH] Ignore broken tRNS

---
 src/reduction/color.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/reduction/color.rs b/src/reduction/color.rs
index b7c07512..42d47c9b 100644
--- a/src/reduction/color.rs
+++ b/src/reduction/color.rs
@@ -111,6 +111,7 @@ pub fn reduced_color_to_palette(png: &PngImage) -> Option<PngImage> {
     let transparency_pixel = png
         .transparency_pixel
         .as_ref()
+        .filter(|t| png.ihdr.color_type == ColorType::RGB && t.len() >= 6)
         .map(|t| RGB8::new(t[1], t[3], t[5]));
     for line in png.scan_lines() {
         raw_data.push(line.filter);