[FFmpeg-devel] [FFmpeg-cvslog] ffplay: only use hardware accelerated SDL texture formats

Michael Niedermayer michael at niedermayer.cc
Tue Apr 17 15:49:48 EEST 2018


On Tue, Apr 17, 2018 at 01:27:48AM +0200, Marton Balint wrote:
> 
> 
> On Mon, 16 Apr 2018, Michael Niedermayer wrote:
> 
> >Hi
> >
> >On Sat, Nov 04, 2017 at 06:28:58PM +0000, Marton Balint wrote:
> >>ffmpeg | branch: master | Marton Balint <cus at passwd.hu> | Sat Oct 28 22:46:08 2017 +0200| [415038f2bd321a3b41564d4e0c6c17d7a096c397] | committer: Marton Balint
> >>
> >>ffplay: only use hardware accelerated SDL texture formats
> >
> >This breaks ffplay playing some files like:
> >./ffplay fate-suite//cvid/catfight-cvid-pal8-partial.mov -noframedrop
> >
> >The output is completely black since this commit
> 
> Seems like a bug in swscale (pal8 -> bgra conversion), the alpha is 0
> instead of 255.

the file seems to store alpha = 0
SDL seems to treat alpha=0 different between PAL8 and RGBA, or maybe iam
missing something

try this:

diff --git a/libavformat/qtpalette.c b/libavformat/qtpalette.c
index 666c6b7351..51a134d30a 100644
--- a/libavformat/qtpalette.c
+++ b/libavformat/qtpalette.c
@@ -104,6 +104,7 @@ int ff_get_qtpalette(int codec_id, AVIOContext *pb, uint32_t *palette)
                     avio_r8(pb);
                     b = avio_r8(pb);
                     avio_r8(pb);
+                    a = 0xFF;
                     palette[i] = (a << 24 ) | (r << 16) | (g << 8) | (b);
                 }
             }
             
swscale does not introduce the alpha=0 its there before

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

What does censorship reveal? It reveals fear. -- Julian Assange
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