Recherche avancée

Sur d’autres sites (9912)

• How to configure FFmpeg in windows ? [closed]

  2 août 2021, par GrassWarlock

  Hey there i'm not very tech savvy.

  


  when i invoke this command :

  


  ffmpeg -i input.mp4 -i subtitles.srt -map 0 -map 1 -c copy -c:v libx264 -crf 23 -preset veryfast output.mp4


  


  ( which is supposed to overlay 'input.mp4' with subtitles from 'subtitle.srt' )

  


  i get the following output :

  


  ffmpeg version 2021-07-27-git-0068b3d0f0-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers
  built with gcc 10.3.0 (Rev5, Built by MSYS2 project)
  configuration: --enable-gpl --enable-version3 --enable-static --disable-w32threads --disable-autodetect --enable-fontconfig --enable-iconv --enable-gnutls --enable-libxml2 --enable-gmp --enable-lzma --enable-libsnappy --enable-zlib --enable-librist --enable-libsrt --enable-libssh --enable-libzmq --enable-avisynth --enable-libbluray --enable-libcaca --enable-sdl2 --enable-libdav1d --enable-libzvbi --enable-librav1e --enable-libsvtav1 --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-libaom --enable-libopenjpeg --enable-libvpx --enable-libass --enable-frei0r --enable-libfreetype --enable-libfribidi --enable-libvidstab --enable-libvmaf --enable-libzimg --enable-amf --enable-cuda-llvm --enable-cuvid --enable-ffnvcodec --enable-nvdec --enable-nvenc --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-libglslang --enable-vulkan --enable-opencl --enable-libcdio --enable-libgme --enable-libmodplug --enable-libopenmpt --enable-libopencore-amrwb --enable-libmp3lame --enable-libshine --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libilbc --enable-libgsm --enable-libopencore-amrnb --enable-libopus --enable-libspeex --enable-libvorbis --enable-ladspa --enable-libbs2b --enable-libflite --enable-libmysofa --enable-librubberband --enable-libsoxr --enable-chromaprint
  libavutil      57.  2.100 / 57.  2.100
  libavcodec     59.  3.102 / 59.  3.102
  libavformat    59.  4.101 / 59.  4.101
  libavdevice    59.  0.100 / 59.  0.100
  libavfilter     8.  1.103 /  8.  1.103
  libswscale      6.  0.100 /  6.  0.100
  libswresample   4.  0.100 /  4.  0.100
  libpostproc    56.  0.100 / 56.  0.100
Input #0, matroska,webm, from 'video.mkv':
  Metadata:
    ENCODER         : Lavf59.4.101
  Duration: 00:05:39.94, start: 0.000000, bitrate: 665 kb/s
  Stream #0:0(eng): Video: vp9 (Profile 0), yuv420p(tv), 720x480, SAR 1:1 DAR 3:2, 29.97 fps, 29.97 tbr, 1k tbn (default)
    Metadata:
      DURATION        : 00:05:39.839000000
  Stream #0:1: Audio: aac (LC), 44100 Hz, stereo, fltp (default)
    Metadata:
      HANDLER_NAME    : SoundHandler
      VENDOR_ID       : [0][0][0][0]
      DURATION        : 00:05:39.940000000
Input #1, srt, from 'subtitles.srt':
  Duration: N/A, bitrate: N/A
  Stream #1:0: Subtitle: subrip
[mp4 @ 000001aa596242c0] Could not find tag for codec subrip in stream #2, codec not currently supported in container
Could not write header for output file #0 (incorrect codec parameters ?): Invalid argument
Error initializing output stream 0:2 --
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
  Stream #1:0 -> #0:2 (copy)
    Last message repeated 1 times


  


  i searched the internet and the official documentation mentions that libass should be enabled in the configuration in order for subtitling to work

  


  


  11.218 subtitles

  


  Draw subtitles on top of input video using the libass library.

  


  To enable compilation of this filter you need to configure FFmpeg with
—enable-libass. This filter also requires a build with libavcodec and libavformat to convert the passed subtitles file to ASS (Advanced
Substation Alpha) subtitles format

  


  


  how do i enable libass in configuration on windows ? my FFmpeg directory doesn't contain a configuration file nor a command that configures it from cmd

  


  Thanks alot in advance

  


• Problem in playing fragmented MP4 that create with FFMPEG

  18 août 2021, par Micle

  For creating fragmented MP4 video file, I'm using FFMPEG AVCodec library(Accord VideoWriter) and set movflags with value frag_keyframe+empty_moov based on How to output fragmented mp4 with ffmpeg ?

  


   av_dict_set(&videoOptions, "movflags", "frag_keyframe+empty_moov", 0);
 avformat_write_header(oc, &videoOptions);


  


  Sample output video

  


  As you see, video is not played while all of video frames downloaded completely.
  
I tried to set moov_size , frag_duration and min_frag_duration flags for correction, but doesn't change anything.

  


  Result of all my test :
  


  


• Where are there working exdamples for QSV enabled ffmpeg filters ?

  2 août 2021, par Bart Lederman

  I'm re-posting this question in a modified form because I'm told that stack overflow doesn't allow anyone to ask for the location of documentation. So now I'm not asking for documentation, I just want working examples of how the QSV enabled filters are used, with a specific question on why async doesn't work with vpp_qsv .

  


  I have a PC running Windows which is QSV capable. I've found the codec and at least one QSV filter which really speed up decoding and encoding AVC (x264) videos.

  


  But the experience is extremely aggravating, as I cannot find a list anywhere that I can find on what the filters and arguments actually are.

  


  The closest I've come for vpp_qsv is this :

  


  https://github.com/FFmpeg/FFmpeg/blob/master/libavfilter/vf_vpp_qsv.c

  


  It's a good start, but it has no examples of what the arguments actually are.
Source code doesn't explain how the filters actually work. However, this source code does say that async_depth is a valid qualifier.

  


  The few examples I've been able to find in various places (including stackoverflow) do not work.

  


  By experimentation, I've found that this works :

  


  ffmpeg -hide_banner -init_hw_device qsv=qsv -hwaccel qsv -i "input.mts" -c:a aac -c:v h264_qsv -preset veryslow -vf "vpp_qsv=cw=628:cx=0:w=640:h=480" -q:v 30 "output.mp4"

  


  I can add other things to the filter. For example :

  


  "vpp_qsv=deinterlace=2:cw=628:cx=0:w=640:h=480"

  


  will work. However, this will NOT work :

  


  "vpp_qsv=cw=628:cx=0:w=640:h=480:async_depth=4"

  


  even though there are examples posted that say it will.

  


  [Parsed_vpp_qsv_0 @ 0000000005bff8c0] Option 'async_depth' not found [AVFilterGraph @ 0000000007327dc0] Error initializing filter 'vpp_qsv' with args 'cw=628:cx=0:w=640:h=480:async_depth=4' Error reinitializing filters ! Failed to inject frame into filter network : Option not found Error while processing the decoded data for stream #0:0

  


  I also have been unable to find good examples of using more than one QSV enabled filter at the same time.

  


  I'm using the newest version of ffmpeg I can find :

  


  I :\ffmpeg -version ffmpeg version 4.4-full_build-www.gyan.dev Copyright (c) 2000-2021 the FFmpeg developers built with gcc 10.2.0 (Rev6, Built by MSYS2 project) configuration : —enable-gpl —enable-version3 —enable-static —disable-w32threads —disable-autodetect —enable-fontconfig —enable-iconv —enable-gnutls —enable-libxml 2 —enable-gmp —enable-lzma —enable-libsnappy —enable-zlib —enable-librist —enable-libsrt —enable-libssh —enable-libzmq —enable-avisynth —enable-libbluray —enab le-libcaca —enable-sdl2 —enable-libdav1d —enable-libzvbi —enable-librav1e —enable-libsvtav1 —enable-libwebp —enable-libx264 —enable-libx265 —enable-libxvid —ena ble-libaom —enable-libopenjpeg —enable-libvpx —enable-libass —enable-frei0r —enable-libfreetype —enable-libfribidi —enable-libvidstab —enable-libvmaf —enable-lib zimg —enable-amf —enable-cuda-llvm —enable-cuvid —enable-ffnvcodec —enable-nvdec —enable-nvenc —enable-d3d11va —enable-dxva2 —enable-libmfx —enable-libglslang - -enable-vulkan —enable-opencl —enable-libcdio —enable-libgme —enable-libmodplug —enable-libopenmpt —enable-libopencore-amrwb —enable-libmp3lame —enable-libshine - -enable-libtheora —enable-libtwolame —enable-libvo-amrwbenc —enable-libilbc —enable-libgsm —enable-libopencore-amrnb —enable-libopus —enable-libspeex —enable-libv orbis —enable-ladspa —enable-libbs2b —enable-libflite —enable-libmysofa —enable-librubberband —enable-libsoxr —enable-chromaprint libavutil 56. 70.100 / 56. 70.100 libavcodec 58.134.100 / 58.134.100 libavformat 58. 76.100 / 58. 76.100 libavdevice 58. 13.100 / 58. 13.100 libavfilter 7.110.100 / 7.110.100 libswscale 5. 9.100 / 5. 9.100 libswresample 3. 9.100 / 3. 9.100 libpostproc 55. 9.100 / 55. 9.100

  


  and the output of "ffmpeg -filters" says I have the various QSV enabled filters on my system.

  


  I have searched dozens and dozens of sites including Intel and ffmpeg.org and I cannot find a clear explanation of how the various QSV enabled filters work, with examples that will actually execute on my system. Could someone please point me to where this filter is explained ? (This is NOT, I repeat, NOT a banned request for documentation. I'm asking how to use a specific qualifier in a specific filter.)