On Mon, 2 Jan 2017 00:56:18 -0700 Pavel Koshevoy <pkoshe...@gmail.com> wrote:
> On Sun, Jan 1, 2017 at 6:00 PM, <pkoshe...@gmail.com> wrote: > > From: Pavel Koshevoy <pkoshe...@gmail.com> > > > > NVDEC (CUVID) does not support unlimited video resolutions, so if > > the resolution of the source is known it can be used during > > avcodec_open2 call to fail early, rather than failing later during > > avcodec_send_packet call. > > > > This problem surfaced when trying to decode 5120x2700 h246 video on > > Geforce GT 730 -- avcodec_open2 succeeded but decoding failed. > > --- > > libavcodec/cuvid.c | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/libavcodec/cuvid.c b/libavcodec/cuvid.c > > index 8fc713d..2e70b62 100644 > > --- a/libavcodec/cuvid.c > > +++ b/libavcodec/cuvid.c > > @@ -625,8 +625,8 @@ static int > > cuvid_test_dummy_decoder(AVCodecContext *avctx, CUVIDPARSERPARAMS > > *cu cuinfo.ChromaFormat = cudaVideoChromaFormat_420; > > cuinfo.OutputFormat = cudaVideoSurfaceFormat_NV12; > > > > - cuinfo.ulWidth = 1280; > > - cuinfo.ulHeight = 720; > > + cuinfo.ulWidth = avctx->coded_width ? avctx->coded_width : > > 1280; > > + cuinfo.ulHeight = avctx->coded_height ? avctx->coded_height : > > 720; cuinfo.ulTargetWidth = cuinfo.ulWidth; > > cuinfo.ulTargetHeight = cuinfo.ulHeight; > > > > -- > > 2.9.2 > > > > > Perhaps a more comprehensive solution is needed. I've run into the > same problem again (avcodec_open2 succeeds, decoding spits errors) > when I tried to play back an mpeg2 stream with YUV422P pixel format. > > I have a new patch but I'd like to test it on a Pascal GPU first. I > am still hoping that 422 decoding will work. It looks like it should > be supported, but I've observed on Geforce GT 730 that even though I > can instantiate a cuvid decoder with cudaVideoChromaFormat_422 without > error -- the decoded video is garbage everywhere except for 16-pixel > wide column along the left edge of the frame. > > In ee88dcb2 cuvid_handle_video_sequence was hard-coded to error-out if > the chroma format is not 420. This looks like an NVIDIA driver/cuvid > bug... does anyone know how to bring it to their attention? It is documented as only supporting 420, even though it doesn't return an error, so it's not a bug per-se - it's just that they don't detect and return an error, so we do it ourselves. --phil _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
