On Thu, Sep 12, 2019 at 5:05 PM Mark Thompson <s...@jkqxz.net> wrote:
> On 03/09/2019 02:02, Aman Gupta wrote: > > From: Jonas Karlman <jo...@kwiboo.se> > > > > This allows the cli to create a dummy drm hwcontext > > that can be shared between the v4l2 decoder/scaler/encoder. > > > > This is especially useful on older RPI3 where /dev/dri devices > > are not available in the default configuration. > > > > Signed-off-by: Jonas Karlman <jo...@kwiboo.se> > > Signed-off-by: Aman Gupta <a...@tmm1.net> > > --- > > libavutil/hwcontext_drm.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/libavutil/hwcontext_drm.c b/libavutil/hwcontext_drm.c > > index 32cbde82eb..aa4794c5e6 100644 > > --- a/libavutil/hwcontext_drm.c > > +++ b/libavutil/hwcontext_drm.c > > @@ -43,6 +43,11 @@ static int drm_device_create(AVHWDeviceContext > *hwdev, const char *device, > > AVDRMDeviceContext *hwctx = hwdev->hwctx; > > drmVersionPtr version; > > > > + if (device == NULL) { > > + hwctx->fd = -1; > > + return 0; > > + } > > + > > hwctx->fd = open(device, O_RDWR); > > if (hwctx->fd < 0) > > return AVERROR(errno); > > > > This smells like a hack for making something work in the ffmpeg > command-line utility. Can you explain the use-case? If necessary, > modifying the behaviour of ffmpeg would probably be better than putting > this sort of thing into the library. > Since this v4l2 decoder can output either software frames or DRM frames, this allows using the CLI to switch between the two modes. i.e.: ffmpeg -c:v h264_v4l2m2m -i sample.mpg vs ./ffmpeg -hwaccel drm -hwaccel_output_format drm_prime -c:v h264_v4l2m2m -i sample.mpg This is also why I made the decoder define itself as AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX, so it was possible to use the CLI to trigger the DRM prime decoding mode. It sounds like it might be better to define a new v4l2 hwaccel/hwdevice, and maybe just return EINVAL from it's map/transfer methods since those are not applicable? Aman > > - Mark > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".