[vlc-commits] [Git][videolan/vlc][3.0.x] 3 commits: Revert "codec: avcodec: fix mask mappings for 32 bits RGB"

[Steve Lhomme (@robUx4)]

Steve Lhomme pushed to branch 3.0.x at VideoLAN / VLC


Commits:
a1671b79 by Steve Lhomme at 2026-05-02T13:03:12+00:00
Revert "codec: avcodec: fix mask mappings for 32 bits RGB"

This reverts commit feada68ef67ff6d94e39e7b63ffdef3203aa5563.

Fixes #29818

- - - - -
faf9f526 by Steve Lhomme at 2026-05-02T13:03:12+00:00
avcodec/chroma: prioritize RGB mapping with the same mask

If the mask corresponds exactly, we have an exact match. If the RGB source
has a mask but none of the RGB mapping uses the same mask, we map to
a close RGB format with a different mask.

It's better than using the first VLC_CODEC_RGBxx in the list if there's
one corresponding to the exact match.

Another option would be to move the VLC_RGB_ES() calls at the end of the
list.

(cherry picked from commit a309fb4c10f238bb2319abe9ec489daa0c91521c)
Signed-off-by: Steve Lhomme <robux4 at ycbcr.xyz>

- - - - -
7c1e5ca5 by Steve Lhomme at 2026-05-02T13:03:12+00:00
codec: avcodec: prioritize RGB with mask set to 0

GetVlcChroma() passes a libavutil chroma without a mask.
AV_PIX_FMT_RGB32 is also AV_PIX_FMT_RGBA (or AV_PIX_FMT_BGRA depending on the endianess).
So we returned VLC_CODEC_RGB32 with a mask rather than the proper VLC_CODEC_RGBA.

FindVlcChroma() had the same problem but it doesn't return a mask.
So returning VLC_CODEC_RGB32 is even more problematic.

GetFfmpegChroma() is unaffected as we match the mask first.

FindFfmpegChroma() is only used to check the format can be mapped.

Fixes #29535

- - - - -


1 changed file:

- modules/codec/avcodec/chroma.c


Changes:

=====================================
modules/codec/avcodec/chroma.c
=====================================
@@ -144,13 +144,18 @@ static const struct
     VLC_RGB( VLC_CODEC_RGB15, AV_PIX_FMT_RGB555, AV_PIX_FMT_BGR555, 0x7c00, 0x03e0, 0x001f )
     VLC_RGB( VLC_CODEC_RGB16, AV_PIX_FMT_RGB565, AV_PIX_FMT_BGR565, 0xf800, 0x07e0, 0x001f )
     VLC_RGB( VLC_CODEC_RGB24, AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, 0xff0000, 0x00ff00, 0x0000ff )
-    VLC_RGB( VLC_CODEC_RGB32, AV_PIX_FMT_0RGB, AV_PIX_FMT_0BGR, 0x00ff0000, 0x0000ff00, 0x000000ff)
-    VLC_RGB( VLC_CODEC_RGB32, AV_PIX_FMT_RGB0, AV_PIX_FMT_BGR0, 0xff000000, 0x00ff0000, 0x0000ff00)
 
     {VLC_CODEC_RGBA, AV_PIX_FMT_RGBA, 0, 0, 0 },
     {VLC_CODEC_ARGB, AV_PIX_FMT_ARGB, 0, 0, 0 },
     {VLC_CODEC_BGRA, AV_PIX_FMT_BGRA, 0, 0, 0 },
 
+    VLC_RGB( VLC_CODEC_RGB32, AV_PIX_FMT_RGB32, AV_PIX_FMT_BGR32, 0x00ff0000, 0x0000ff00, 0x000000ff )
+    VLC_RGB( VLC_CODEC_RGB32, AV_PIX_FMT_RGB32_1, AV_PIX_FMT_BGR32_1, 0xff000000, 0x00ff0000, 0x0000ff00 )
+
+#ifdef AV_PIX_FMT_0BGR32
+    VLC_RGB( VLC_CODEC_RGB32, AV_PIX_FMT_0BGR32, AV_PIX_FMT_0RGB32, 0x000000ff, 0x0000ff00, 0x00ff0000 )
+#endif
+
 #if (LIBAVUTIL_VERSION_MICRO == 0 || LIBAVUTIL_VERSION_CHECK( 55, 0, 100 ) )
 #ifdef WORDS_BIGENDIAN
     {VLC_CODEC_RGBA64, AV_PIX_FMT_RGBA64BE, 0, 0, 0 },
@@ -194,14 +199,23 @@ int GetFfmpegChroma( int *restrict i_ffmpeg_chroma, const video_format_t *fmt )
 {
     for( int i = 0; chroma_table[i].i_chroma != 0; i++ )
     {
-        if( chroma_table[i].i_chroma == fmt->i_chroma )
+        if( chroma_table[i].i_chroma == fmt->i_chroma &&
+            chroma_table[i].i_rmask  == fmt->i_rmask &&
+            chroma_table[i].i_gmask  == fmt->i_gmask &&
+            chroma_table[i].i_bmask  == fmt->i_bmask )
+        {
+            return chroma_table[i].i_chroma_id;
+        }
+    }
+    // try again without the mask as they may not correspond exactly
+    if (fmt->i_rmask || fmt->i_gmask || fmt->i_bmask)
+    {
+        for( int i = 0; chroma_table[i].i_chroma != 0; i++ )
         {
-            if( ( chroma_table[i].i_rmask == 0 &&
-                  chroma_table[i].i_gmask == 0 &&
-                  chroma_table[i].i_bmask == 0 ) ||
-                ( chroma_table[i].i_rmask == fmt->i_rmask &&
-                  chroma_table[i].i_gmask == fmt->i_gmask &&
-                  chroma_table[i].i_bmask == fmt->i_bmask ) )
+            if( chroma_table[i].i_chroma == fmt->i_chroma &&
+                chroma_table[i].i_rmask == 0 &&
+                chroma_table[i].i_gmask == 0 &&
+                chroma_table[i].i_bmask == 0 )
             {
                 *i_ffmpeg_chroma = chroma_table[i].i_chroma_id;
                 return VLC_SUCCESS;



View it on GitLab: https://code.videolan.org/videolan/vlc/-/compare/049988e7860b6fd4f70de054548ae9c209281660...7c1e5ca5df2267cdab8f9ca785c6de7d6cd21168

-- 
View it on GitLab: https://code.videolan.org/videolan/vlc/-/compare/049988e7860b6fd4f70de054548ae9c209281660...7c1e5ca5df2267cdab8f9ca785c6de7d6cd21168
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