[FFmpeg-user] hw_decode.c on osx?

[su.00048 at cherry.org]

on 2020.04.18 17:03 +0200, carl eugen wrote:

> Am Fr., 17. Apr. 2020 um 14:37 Uhr schrieb su.00048---:
> > 
> > i have ffmpeg building successfully on osx (10.14.6; xcode 11.3.1),
> > and am using the generated libraries in a personal video project i'm
> > working on.  now i'm ready to start thinking about implementing hardware
> > decoding ...  i tried adapting some of the code from hw_decode.c, but
> > ran into runtime errors.  thinking that it was my code that was at
> > fault, i then compiled hw_decode by itself, but i get the same errors
> > even there.  is anyone aware of hw_decode.c not working on osx?
> > 
> > trying to decode known good videos, either h264 or hevc, results in
> > some internal errors (see below).  the videos behave as expected when
> > opened with my locally built versions of ffplay or ffmpeg, however.
> > 
> > h264 example:
> > 
> >    % hwdecode videotoolbox h264.mov h264.out
> > 
> >    [h264 @ 0x7f8a2b003e00] get_buffer() failed
> >    Assertion src->f->buf[0] failed at libavcodec/h264_picture.c:70
> >    Abort
> > 
> > hevc fails differently:
> > 
> >    % hwdecode videotoolbox hevc.mov hevc.out
> > 
> >    [hevc @ 0x7f8464814600] get_buffer() failed
> >    [hevc @ 0x7f8464814600] videotoolbox: invalid state
> >    [hevc @ 0x7f8464814600] hardware accelerator failed to decode picture
> >    Error during decoding
> >    Error during decoding
> > 
> > there are no significant warnings, etc., when building the executable,
> > so i'm pretty sure everything is ok there.  videotoolbox shows up as
> > being available in the output of configure.
> > 
> > any suggestions as to what might be going wrong?
> 
> Did you see ticket #8615?

no, i hadn't seen that.  thanks.  

that does look very much like the same issue.  compiler version in the bug
report looks like the same one i'm using, so it could be that the reporter is
also still on mojave.  i don't have a catalina machine to test on, so i can't
check to see if things are any different there.  my builds are based on commit
59e3a9aede5e2f9271c82583d8724c272ce33a0a (2020.04.13; same day), if that's any
help ...  now that i know this is presumably a bug, if i get some time, i will
try to investigate what's going on, but i'm not very familiar with the ffmpeg
codebase ...  anyway, will keep monitoring issue 8615 in the meanwhile.  thanks
again for the info.