[FFmpeg-devel] [PATCH] lavc/dxv: assume DXV2 files use premultiplied alpha

[Connor Worley]

I generated a DXV2 file with an interesting alpha channel using
Adobe Media Encoder 2015 and compared decoding it using Resolume Alley
and ffmpeg. Similarly to DXV3 files, Alley expects premultiplied alpha
and ffmpeg matches its decoding more closely when it does the same.

Reference file: https://connorworley.com/dxv2-dxt5.mov

Existing FATE tests for DXV2 files do not cover this change.

Signed-off-by: Connor Worley <connorbworley at gmail.com>
---
 libavcodec/dxv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/dxv.c b/libavcodec/dxv.c
index 82c493f1de..2eca14c129 100644
--- a/libavcodec/dxv.c
+++ b/libavcodec/dxv.c
@@ -923,7 +923,7 @@ static int dxv_decode(AVCodecContext *avctx, AVFrame *frame,
             tag = DXV_FMT_DXT5;
             msgtext = "DXT5";
 
-            texdsp_ctx.tex_funct = ctx->texdsp.dxt5_block;
+            texdsp_ctx.tex_funct = ctx->texdsp.dxt4_block;
             texdsp_ctx.tex_ratio = 16;
             texdsp_ctx.raw_ratio = 16;
         } else if (old_type & 0x20 || version_major == 1) {
-- 
2.43.1