> On Wed, 2021-09-22 at 15:42 +0800, Haihao Xiang wrote: > > Usually a HW decoder is expected when user specifies a HW acceleration > > method via -hwaccel option, however the current implementation doesn't > > take HW acceleration method into account, it is possible to select a SW > > decoder. > > > > For example: > > > > $> ffmpeg -hwaccel vaapi -i av1.ivf -f null - > > ... > > Stream #0:0 -> #0:0 (av1 (libdav1d) -> wrapped_avframe (native)) > > > > libdav1d is selected in this case even if vaapi is specified. > > > > After applying this patch, the native av1 decoder (with vaapi support) > > is selected. > > ... > > Stream #0:0 -> #0:0 (av1 (native) -> wrapped_avframe (native)) > > Any comment for this patchset? We may simplify the command line using HW > acceleration method after applying this patchset.
Ping again. According to the help string for -hwaccel option, HW accelerated decoding is used if -hwaccel arg is specified. However in the current code, hwaccel is not taken into account when choosing a codec for the video stream, (see https://github.com/FFmpeg/FFmpeg/blob/master/fftools/ffmpeg_opt.c#L792-L805). For example, libdav1d is selected (if libdav1d is available) when running the command below because libdav1d has higher priority than the native av1 decoder in the current FFmpeg. $> ffmpeg -hwaccel vaapi -i av1.ivf -f null - (Note `ffmpeg -hwaccel vaapi -i input.h264 -f null -` works as expected, the native h264 decoder is selected) This patch enabled the automatic codec selection for hw accelerated decoding, -hwaccel option can work as expected after applying this patch. Thanks Haihao > > --- > > fftools/ffmpeg_opt.c | 44 +++++++++++++++++++++++++++++++++++++++++++- > > 1 file changed, 43 insertions(+), 1 deletion(-) > > > > diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c > > index 2d9a8a2ea0..914078add9 100644 > > --- a/fftools/ffmpeg_opt.c > > +++ b/fftools/ffmpeg_opt.c > > @@ -804,6 +804,48 @@ static const AVCodec *choose_decoder(OptionsContext *o, > > AVFormatContext *s, AVSt > > return avcodec_find_decoder(st->codecpar->codec_id); > > } > > > > +static const AVCodec *choose_decoder2(InputStream *ist, OptionsContext *o, > > AVFormatContext *s, AVStream *st) > > +{ > > + char *codec_name = NULL; > > + > > + MATCH_PER_STREAM_OPT(codec_names, str, codec_name, s, st); > > + if (codec_name) { > > + const AVCodec *codec = find_codec_or_die(codec_name, st->codecpar- > > > codec_type, 0); > > > > + st->codecpar->codec_id = codec->id; > > + if (recast_media && st->codecpar->codec_type != codec->type) > > + st->codecpar->codec_type = codec->type; > > + return codec; > > + } else { > > + if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && > > + ist->hwaccel_id == HWACCEL_GENERIC && > > + ist->hwaccel_device_type != AV_HWDEVICE_TYPE_NONE) { > > + const AVCodec *p; > > + void *i = 0; > > + > > + while ((p = av_codec_iterate(&i))) { > > + int j; > > + > > + if (p->id != st->codecpar->codec_id || > > + !av_codec_is_decoder(p) || > > + !avcodec_get_hw_config(p, 0)) > > + continue; > > + > > + for (j = 0; ;j++) { > > + const AVCodecHWConfig *config = > > avcodec_get_hw_config(p, > > j); > > + > > + if (!config) > > + break; > > + > > + if (config->device_type == ist->hwaccel_device_type) > > + return p; > > + } > > + } > > + } > > + > > + return avcodec_find_decoder(st->codecpar->codec_id); > > + } > > +} > > + > > /* Add all the streams from the given input file to the global > > * list of input streams. */ > > static void add_input_streams(OptionsContext *o, AVFormatContext *ic) > > @@ -932,7 +974,7 @@ static void add_input_streams(OptionsContext *o, > > AVFormatContext *ic) > > ist->hwaccel_pix_fmt = AV_PIX_FMT_NONE; > > } > > > > - ist->dec = choose_decoder(o, ic, st); > > + ist->dec = choose_decoder2(ist, o, ic, st); > > ist->decoder_opts = filter_codec_opts(o->g->codec_opts, ist->st- > > > codecpar->codec_id, ic, st, ist->dec); > > > > > > ist->reinit_filters = -1; > > _______________________________________________ > 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".
