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• lavc : shedule old encoding/decoding API for removal

  25 janvier 2021, par Anton Khirnov

  lavc : shedule old encoding/decoding API for removal
  It has been deprecated for 4 years and certain new codecs do not work
  
  with it.
  Also include AVCodecContext.refcounted_frames, as it has no effect with
  
  the new API.
  

  • [DH] libavcodec/avcodec.h
  • [DH] libavcodec/decode.c
  • [DH] libavcodec/encode.c
  • [DH] libavcodec/internal.h
  • [DH] libavcodec/options_table.h
  • [DH] libavcodec/utils.c
  • [DH] libavcodec/version.h

• ffmpeg - maintain video quality as I apply multi-pass workflow, each includes decoding and encoding again, in video editing

  27 septembre 2020, par QRrabbit

  I'm using FFMPEG libraries do do some video manipulation, and due to complexity of filters and image overlaying, I have to run the process in multiple passes.
This means, my process is as such :
Open original video, decode it, run -complex_filter, recompress the video in whichever format the original video was encoded.
Open the output from the first pass, run another -complex_filter, etc-etc.
Sometimes I have to do the above 3-4 times. My concern is that the video, with every compression is losing quality - obvious signs of that is the file is shrinking in size with every pass.

  


  With the above, I have two questions :

  


  


  1. Would it make sense to, after first manipulation, instead of saving the video in its original format, I chose some format that is lossless, and then perform my passes one after the other, knowing that the quality remains the same, then on the final pass I recompress one-time into the format of the source. If so, what format of a video would you recommend ? ProRes 4444 ? Any other formats I shell consider ? Any parameters I should set and carry-over from encoding to encoding ?

     


  


  2. With every step I carry over all extra streams of audio and other meta data.
Wouldn't it be more efficient to strip everything except the video, run my video passages over and over and not to need for adding -c:a copy and c:s copy ? Then on my final run, merge all streams from the original source to the output file ? If yes, how will I carry the ffmpeg command specifically ? I have a video that has 1 video stream + 15 audio streams + some extra tmcd which my ffmpeg cannot read.

     


  


  


  Thank you.

  


  Edit 1 :

  


  if the input video has a video codec = dvvideo, and if dimensions of the video is 1280x1080, that means the video doesn't have a typical square pixels.
I first need to resize the video, in doing so I scale the video up. Then I can run my filters :

  


  pass-1 : -vf scale=1920x1080 (this step is skipped if the video is of a normal x to y ratio)
pass-2 : -filter_complex : which calls my special filter that adds some proprietary watermark to a video
pass-3 : -filter_complex : "0overlay=5:21:enable='between(t,2,3)+between(t,4,5)+between(t,6,8)'" (sole objective is to inserts an icon.png at a location near where the watermark was placed in previous step.)
pass-4 : -vf scale=1280x1080 (this step scales the video back, if pass-1 was executed)

  


  I could probably rewrite my 'C' filter code at some point in the future to accommodate this logic of checking for 1280x1080, as well as inserting this icon.png, and do it all in one step, but for right now, I thought just using 2-step process if a normal video, or a 4 passes if needs scaling, and utilize something of a lossless format as a temp file solution (I arbitrary chose ProRes 4444 v5, but open to suggestions), should minimize the losses during recompression to the video.

  


  Steps 1 and 4 are conditional, and only applicable if :&#xA;if vcodec == 'dvvideo' and aspect_ratio < 1.2 : # 1280x1080 ratio has about 1.16&#xA;I run steps 1->4. Otherwise only steps 2 & 3 :

  &#xA;

  Step1 :

  &#xA;

  ffmpeg -i in.mov -vf scale=1920x1080 -map 0:v? -map 0:a? -map 0:s? -map_metadata 0 -b:v 115084915 -maxrate 115084915 -minrate 115084915 -c:v prores_ks -profile:v 5 -preset ultrafast -crf 0 -c:a copy -timecode 00:00:00.00 -c:s copy -y step2.mov


  &#xA;

  Step2 :

  &#xA;

  ffmpeg -i step2.mov -filter_complex " myFilter=enable='between(t,0,30)':x=15:y=25:size=95:etc-etc..." -map 0:v? -map 0:a? -map 0:s? -map_metadata 0 -b:v 115084915 -maxrate 115084915 -minrate 115084915 -c:v prores_ks -profile:v 5 -preset ultrafast -crf 0 -c:a copy -timecode 00:00:00.00 -c:s copy -y step3.mov


  &#xA;

  Step3 :

  &#xA;

  ffmpeg -i step3.mov -i icon.png -filter_complex "[0][1]overlay=15:20:enable='between(t,1,3.600)+between(t,4,5.500)+between(t,6,20)' " -map 0:v? -map 0:a? -map 0:s? -map_metadata 0 -b:v 115084915 -maxrate 115084915 -minrate 115084915 -c:v prores_ks -profile:v 5 -preset ultrafast -crf 0 -c:a copy -timecode 00:00:00.00 -c:s copy -y step4.mov


  &#xA;

  Step4 :

  &#xA;

  ffmpeg -i step4.mov -map 0:v? -vf scale=1280x1080 -map 0:a? -map 0:s? -c:v dvvideo -pix_fmt yuv422p -b:v 115084915 -maxrate 115084915 -minrate 115084915 -r 29.97 -top 1 -color_primaries bt709 -color_trc bt709 -colorspace bt709 -vtag dvh6 -map_metadata 0 -c:a copy -timecode 00:00:00.00 -c:s copy -y final-output.mov


  &#xA;

  Since I post my entire set of ffmpeg commands, maybe someone could recommend how to make my output match input so that I don't lose timecode entry :

  &#xA;

• ffmpeg Hardware decoding/encoding transcoding

  21 juillet 2020, par Michael McConnell

  I am running FFmpeg from the command line as below...

  &#xA;

  ffmpeg -hwaccel_output_format cuda -c:v h264_cuvid -i rtmp://127.0.0.1:1935/live/$name -vcodec h264_nvenc -acodec aac -b:v 768k -b:a 96k -vf "scale=852:trunc(ow/a/2)*2" -tune zerolatency -crf 27 -f flv rtmp://localhost:1935/show/$name_480 -vcodec h264_nvenc -acodec aac -b:v 1920k -b:a 128k -vf "scale=1280:trunc(ow/a/2)*2" -tune zerolatency -crf 27 -f flv rtmp://localhost:1935/show/$name_720 -c copy -f flv rtmp://localhost:1935/show/$name_src


  &#xA;

  In theory, this should be decoding the source RTMP stream and then re-encoding to 480p and 720p (roughly) using the settings in the command, all on hardware. However, it seems that this is not the case as FFmpeg is still using roughly 50% CPU when running.

  &#xA;

  the card being used is a Nvidia Quadro p2000

  &#xA;

  ffmpeg has all of the options available :

  &#xA;

  ffmpeg -hwaccels
ffmpeg version 4.2.2-1ubuntu1 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.3.0-3ubuntu1)
  configuration: --prefix=/usr --extra-version=1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Hardware acceleration methods:
vdpau
cuda
vaapi
drm
opencl
cuvid


  &#xA;

  Output of -encoders

  &#xA;

  ffmpeg -encoders |grep nvenc
ffmpeg version 4.2.2-1ubuntu1 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.3.0-3ubuntu1)
  configuration: --prefix=/usr --extra-version=1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
 V..... h264_nvenc           NVIDIA NVENC H.264 encoder (codec h264)
 V..... nvenc                NVIDIA NVENC H.264 encoder (codec h264)
 V..... nvenc_h264           NVIDIA NVENC H.264 encoder (codec h264)
 V..... nvenc_hevc           NVIDIA NVENC hevc encoder (codec hevc)
 V..... hevc_nvenc           NVIDIA NVENC hevc encoder (codec hevc)


  &#xA;

  Output of decoders :

  &#xA;

  ffmpeg -decoders |grep cuvid
ffmpeg version 4.2.2-1ubuntu1 Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9 (Ubuntu 9.3.0-3ubuntu1)
  configuration: --prefix=/usr --extra-version=1ubuntu1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opencl --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-nvenc --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
 V..... h264_cuvid           Nvidia CUVID H264 decoder (codec h264)
 V..... hevc_cuvid           Nvidia CUVID HEVC decoder (codec hevc)
 V..... mjpeg_cuvid          Nvidia CUVID MJPEG decoder (codec mjpeg)
 V..... mpeg1_cuvid          Nvidia CUVID MPEG1VIDEO decoder (codec mpeg1video)
 V..... mpeg2_cuvid          Nvidia CUVID MPEG2VIDEO decoder (codec mpeg2video)
 V..... mpeg4_cuvid          Nvidia CUVID MPEG4 decoder (codec mpeg4)
 V..... vc1_cuvid            Nvidia CUVID VC1 decoder (codec vc1)
 V..... vp8_cuvid            Nvidia CUVID VP8 decoder (codec vp8)
 V..... vp9_cuvid            Nvidia CUVID VP9 decoder (codec vp9)


  &#xA;

  Could the CPU utilization be correlated to the audio transcoding or would that be handled in hardware as well ?

  &#xA;

  Any ideas ?

  &#xA;