LibGfx/JPEG: Accept grayscale images with an App14 segment

The adobe specification doesn't even consider JPEG images with a single component. So let's not consider the content of the App14 segment for grayscale images.
Author: https://github.com/LucasChollet Commit: https://github.com/SerenityOS/serenity/commit/af14ed6b2e Pull-request: https://github.com/SerenityOS/serenity/pull/19574
2023-06-23 00:15:49 -04:00 · 2023-06-23 00:15:49 -04:00 · af14ed6b2e · 2024-07-16 23:05:02 +09:00
commit af14ed6b2e
parent 8df714ff1e
1 changed files with 3 additions and 1 deletions
--- a/Userland/Libraries/LibGfx/ImageFormats/JPEGLoader.cpp
+++ b/Userland/Libraries/LibGfx/ImageFormats/JPEGLoader.cpp
@ -1687,7 +1687,9 @@ static void ycck_to_rgb(JPEGLoadingContext const& context, Vector<Macroblock>& m

 static ErrorOr<void> handle_color_transform(JPEGLoadingContext const& context, Vector<Macroblock>& macroblocks)
 {
-    if (context.color_transform.has_value()) {
+    // Note: This is non-standard but some encoder still add the App14 segment for grayscale images.
+    //       So let's ignore the color transform value if we only have one component.
+    if (context.color_transform.has_value() && context.components.size() != 1) {
        // https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-T.872-201206-I!!PDF-E&type=items
        // 6.5.3 - APP14 marker segment for colour encoding