[FFmpeg-user] hw_decode.c on osx?

[su.00048 at cherry.org]

on 2020.04.18 07:15 -0400, ted park wrote:

> > videotoolbox decodes to CMSampleBuffer, which is CoreMedia's generic buffer
> > wrapper class.  a couple levels down, it's probably a CVPixelBuffer.  if it's
> > working for you, i'd be curious to know what hardware and what os version
> > you're running on, and what type of file you're feeding to hw_decode.
> 
> Oh okay, makes sense. The one I tried it on had a W5700, I tried again on a
> dual nehalem Xserve with no gpu (almost, has  a GT120 for console/desktop
> monitor) and got similar errors
> 
> xserve:~ admin$ $OLDPWD/hw_decode videotoolbox hd-bars-h264.mov hd-bars-h264.raw
> [h264 @ 0x7fb74d001800] Failed setup for format videotoolbox_vld: hwaccel initialisation returned error.
> Failed to get HW surface format.
> [h264 @ 0x7fb74d001800] decode_slice_header error
> [h264 @ 0x7fb74d001800] no frame!
> Error during decoding
> 
> xserve:~ admin$ $OLDPWD/hw_decode videotoolbox hd-bars-hevc.mp4 hd-bars-hevc.raw
> [hevc @ 0x7fd8a8018a00] get_buffer() failed
> [hevc @ 0x7fd8a8018a00] videotoolbox: invalid state
> [hevc @ 0x7fd8a8018a00] hardware accelerator failed to decode picture
> Error during decoding
> Error during decoding
> 
> The difference would be I didn't expect it to work in the first place I
> guess. Do you know hardware decoding works in ffplay? It's harder to tell for
> mac frameworks imo, I'd try attaching to ffplay and seeing if you can get it
> to use a hardware decoder. Which gpu does the machine have?

you've probably already seen carl eugen's post referring to ticket 8615.  
looks like this may be a regression ...  to answer your question, though,
i'm on a 2018 mini (i7); gpu is "Intel UHD Graphics 630", which should
support hardware decoding for hevc (and certainly for h264).