Recherche avancée

Sur d’autres sites (9879)

• how too download this link with ffmpeg

  27 décembre 2020, par Behrad kabiri

  i want download video with this command in ffmpeg :

  


  ffmpeg -i https://msx.namava.ir/hvod/2020/12/e9936676-eea2-44bd-b17b-dc5e58fd000d/v_854.mp4/index-v1-a1.m3u8?x=EgvsRR7zZLXNoaz49v4D05BwcjHwPaNSOtkB9y98QGOIB_EyAhV_hc44Z4McLT_FTwzBWxpaK1WlNgSBkLd415LU1jRGz0yFNhciw_SDSwgj6OlAQCARiRIb9UU8XMh_dMXKr4KncBfgwnYLMOlUn6zfSa3ltot63vKiuw0CUpU1 -vcodec copy output.mp4

  


  but recive this eror :

  


  [https @ 00000242dbcfeec0] HTTP error 420
https://msx.namava.ir/hvod/2020/12/e9936676-eea2-44bd-b17b-dc5e58fd000d/v_854.mp4/index-v1-a1.m3u8?x=EgvsRR7zZLXNoaz49v4D05BwcjHwPaNSOtkB9y98QGOIB_EyAhV_hc44Z4McLT_FTwzBWxpaK1WlNgSBkLd415LU1jRGz0yFNhciw_SDSwgj6OlAQCARiRIb9UU8XMh_dMXKr4KncBfgwnYLMOlUn6zfSa3ltot63vKiuw0CUpU1 : Server returned 4XX Client Error, but not one of 400,1,3,4

  


  please help me

  


• Convert mp3 to AAC with mpeg-2 container (FFMPEG)

  18 mars 2016, par jsurf

  I’m trying to convert an mp3 audio file to an AAC file with FFMPEG, and I need the audio to be wrapped in an MPEG-2 container.
  The resulting AAC file needs to be AAC-LC (Low Complexity), 1-channel, CBR mode, 44100 sample rate, and 48kb/s bitrate, so I use this command :

  ffmpeg -y -i input.mp3 -ar 44100 -ab 48k -acodec libfdk_aac -ac 1 output.aac

  But when I examine the ADTS headers, the audio file is always being wrapped in an MPEG-4 container. I have tried all the codecs listed here but I still end up with an mpeg-4 container wrapped around the audio : http://trac.ffmpeg.org/wiki/AACEncodingGuide.

  Here are the headers I get when examining the AAC output file :

  mpeg_type : ’MPEG4’,
  profile : 2,
  profile_name : ’AAC LC’,
  sample_freq : 44100,
  channel_config : 1,
  channels : 1,
  frame_length : 139,
  buffer_fullness : 157,
  number_of_frames : 1,
  frames_per_sec : 43.06640625

  Any ideas as to why ffmpeg wraps an mp4 container around the audio ? Can I get around this somehow ? Are there any other encoders I can try aside from FFMPEG ? I was giving FAAC encoder a shot and it gives me the proper encoding and ADTS headers, but alas it does not support mp3, only WAV.

• Setting qscale programmatically when using MPEG4 encoder ( for constant quality / VBR)

  14 février 2019, par Dennis

  i implemented the possibility to encode various self-rendered video-frames with MPEG4 codec and create an .mp4 video file. This works fine. Now i want to add the possibility to define a quality slider (0-100%) to parameterize a factor for constant quality (VBR). I don’t know how to do that.

  I found out that -qscale seems to do what i want, so i looked in ffmpeg_opt.c what happens there and tried the same :

  config.codecContext->flags |= AV_CODEC_FLAG_QSCALE;
  
  config.codecContext->global_quality = FF_QP2LAMBDA * QualityLvl;

  with :

  • "config.codecContext" being the code context
  • "FF_QP2LAMBDA" being 118
  • "QualityLvl" is the "factor for constant quality" (has to be an int between 1 and 31 according to this :
    https://trac.ffmpeg.org/wiki/Encode/MPEG-4)

  The problem is, that it actually doesn’t matter if "QualityLvl" is 1,2 or 30 it always results in the same file size and a visually same(?) video file. I would have expected file size and quality differences ?!