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• What is the difference between "png" and "jpg -q 0" ?

  28 août 2015, par xkfz007

  When you are using ffmpeg to extract images from videos, what is the difference between "png" and "jpg -q 0" ?
  In my opinion, "-q 0" means the quantization is 0 and there is no compression. And the fact is the "jpg -q 0" is much smaller than "png"
  The commands like :

  ffmpeg -i a.mp4 image-%d.png
  
  ffmpeg -i a.mp4 -q 0 image-%d.jpg

• "does not contain any stream" if "EXT-X-MEDIA-SEQUENCE" > 0

  6 mars 2019, par Wonson

  I have a list of .ts files and want to save them as multiple video files.

  ---

  First I have a .m3u8 like this obtained from streaming :

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key"
  
  #EXTINF:3.01,
  
  aaa001_00002.ts
  
  #EXTINF:3.01,
  
  aaa001_00003.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_01944.ts
  
  #EXT-X-ENDLIST

  ---

  Step 1 :

  So, I tried to convert it into several m3u8 like the followings :

  segment1.m3u8

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key"
  
  #EXTINF:3.01,
  
  aaa001_00002.ts
  
  #EXTINF:3.01,
  
  aaa001_00003.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_00569.ts
  
  #EXT-X-ENDLIST

  segment2.m3u8

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:567
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key"
  
  #EXTINF:3.01,
  
  aaa001_00002.ts
  
  #EXTINF:3.01,
  
  aaa001_00003.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_01288.ts
  
  #EXT-X-ENDLIST

  and so on...

  then do the ffmpeg cmd one by one..

  ffmpeg -i /fs/segment2.m3u8 -safe 0 -map 0:v -map 0:a -cpu-used 4 -threads 0 -preset veryfast -c copy -bsf:a aac_adtstoasc output.mp4

  ---

  But those EXT-X-MEDIA-SEQUENCE > 0 (i.e. since segment2.m3u8...) will result in

  "Output file #0 does not contain any stream"

  ---

  Then I tried to make the ’segment2.m3u8’ looks like this

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key"
  
  #EXTINF:3.01,
  
  aaa001_00002.ts <--the first video chunk
  
  #EXTINF:3.01,
  
  aaa001_00570.ts <--the start point of segment 2
  
  #EXTINF:3.01,
  
  aaa001_00571.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_01288.ts
  
  #EXT-X-ENDLIST

  ---

  ffmpeg works fine, and gives me an output video, so it seems the stream channel info is in the first chunk.

  However, there are still several problems

  1. the first chunk of video is in segment2.mp4 which I clearly do not want it here.

  2. the segment2 output video plays first the 3.01s, then freezed the image until the time reach aaa001_00570.ts and play again

  ---

  So, any suggestion so that I can reference the stream info from first chunk ? or ignore it in the playlist, etc ?

  ---

  UPDATE SOLUTION

  As it works when #EXT-X-MEDIA-SEQUENCE:0, and #EXT-X-KEY : IV = by default

  So I add IV=hex(#EXT-X-MEDIA-SEQUENCE)in every playlist

  segment1.m3u8

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key",IV=0x00000000000000000000000000000000
  
  #EXTINF:3.01,
  
  aaa001_00002.ts
  
  #EXTINF:3.01,
  
  aaa001_00003.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_00569.ts
  
  #EXT-X-ENDLIST

  segment2.m3u8

  #EXTM3U
  
  #EXT-X-VERSION:3
  
  #EXT-X-TARGETDURATION:5
  
  #EXT-X-MEDIA-SEQUENCE:567
  
  #EXT-X-KEY:METHOD=AES-128,URI="aaa001_00001.key",IV=0x00000000000000000000000000000237
  
  #EXTINF:3.01,
  
  aaa001_00570.ts
  
  
  
  ...
  
  
  
  #EXTINF:3.01,
  
  aaa001_01288.ts
  
  #EXT-X-ENDLIST

• FFMPEG "Could find no file with path" and "No such file or directory"

  4 mai 2020, par bmw_58

  I try to convert a sequence of pictures to video file. 
But I get from ffmpeg the response, that no such file or directory

  



  Does someone have a solution for it ?

  



  My command line :

  



  ffmpeg -r 1/5 -start_number 0 -i "C:\Users\USER\Desktop\Pictures\%3d.png" -c:v libx264 -r 30 -pix_fmt yuv420p C:\Users\USER\Desktop\Pictures\out.mp4


  



  The error :

  



          C:\Users\USER>ffmpeg -r 1/5 -start_number 0 -i "C:\Users\USER\Desktop\Pictures\%3d.png" -c:v libx264 -r 30 -pix_fmt yuv420p C:\Users\USER\Desktop\Pictures\out.mp4
    ffmpeg version git-2020-05-01-39fb1e9 Copyright (c) 2000-2020 the FFmpeg developers
      built with gcc 9.3.1 (GCC) 20200328
      configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libsrt --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvmaf --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --disable-w32threads --enable-libmfx --enable-ffnvcodec --enable-cuda-llvm --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
      libavutil      56. 43.100 / 56. 43.100
      libavcodec     58. 82.100 / 58. 82.100
      libavformat    58. 42.101 / 58. 42.101
      libavdevice    58.  9.103 / 58.  9.103
      libavfilter     7. 80.100 /  7. 80.100
      libswscale      5.  6.101 /  5.  6.101
      libswresample   3.  6.100 /  3.  6.100
      libpostproc    55.  6.100 / 55.  6.100
    [image2 @ 000002169186c440] Could find no file with path 'C:\Users\USER\Desktop\Pictures\%3d.png' and index in the range 0-4
    C:\Users\USER\Desktop\Pictures\%3d.png: No such file or directory