On Mon, 18 Dec 2023 at 00:55, Dennis Mungai <dmng...@gmail.com> wrote:
> Hello there, > > As tested with FFmpeg 6.1 and git tip master, FFmpeg's H.264 and HEVC QSV > encoder wrappers, ie h264_qsv and hevc_qsv are not accepting the configured > GOP size(s) set via the generic option -g:v. > > A trivial command such as the one shows below demonstrates the failure: > > ffmpeg -thread_queue_size 5120 -nostdin -y -fflags +genpts -y \ > -init_hw_device vaapi=va:/dev/dri/renderD129 \ > -init_hw_device qsv=qs@va \ > -filter_hw_device qs \ > -extra_hw_frames 64 \ > -threads:v 2 -async 1 \ > -probesize 10M -analyzeduration 10M \ > -f mpegts -fix_teletext_pts 1 -scan_all_pmts 1 -merge_pmt_versions 1 \ > -i "input.ts" \ > -vf > 'hwmap=derive_device=qsv,format=qsv,vpp_qsv=deinterlace=2:scale_mode=0:async_depth=4' > \ > -sc_threshold 0 -strict -1 -bitrate_limit:v 0 -g:v 50 -async_depth:v 4 > -look_ahead_depth:v 40 \ > -preset:v medium -refs:v 5 -extbrc:v 1 -bf:v 0 -low_power:v 1 -r:v 25 \ > -b:v 4500k -minrate:v 4500k -maxrate:v 4500k -bufsize:v 9000k > -rc_init_occupancy:v 4500k -c:v h264_qsv \ > -c:a aac -ac 2 -b:a 128k \ > -flags -global_header+cgop -max_muxing_queue_size 2048 -max_interleave_delta > 0 -flush_packets 0 -fps_mode cfr -f mpegts \ > -y "out.ts" > > > And when the output is analyzed with ffprobe via: > > ffprobe -select_streams v -show_entries frame=pict_type,pts_time -of csv=p=0 > -skip_frame nokey -i filter.ts > Iframes.txt > > > The GOP distance is clearly set to 10, instead of the specified value of 2: > > less Iframes.txt > 2.981333,I > 13.221333,I > 23.461333,I > 33.701333,I > 43.941333,I > 54.181333,I > 64.421333,I > 74.661333,I > 84.901333,I > 95.141333,I > 105.381333,I > 115.621333,I > 125.861333,I > 136.101333,I > 146.341333,I > 156.581333,I > 166.821333,I > > > I'll attach the sample file below demonstrating the anomalous GOP size > issue after encoding. > Copying in Xiang and Artem. > > Warm regards, > > Dennis. > Hello there, I fixed it. The root cause of this anomaly is due to the external bit rate control mode in use (-extbrc 1) which also enables mini-GOPs and scenecut detection. Both of these options can be disabled by passing -adaptive_i 1 -adaptive_b 1 _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email ffmpeg-user-requ...@ffmpeg.org with subject "unsubscribe".
