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• How can I set a Clean Aperture on a QuickTime file in ffmpeg ? [closed]

  5 novembre 2024, par blackirishman

  I am using ffmpeg to convert files to QuickTime containers. I understand that certain QuickTime files requires clap atoms, ie "This is a mandatory extension for all uncompressed Y´CbCr data formats."

  


  https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html#//apple_ref/doc/uid/TP40000939-CH205-125850

  


  Is there a way to specify a clap atom when using ffmpeg to output a QuickTime file ? Otherwise would there be harm in adding a clap atom at the end of the file assuming that I updated any file length field ? Lastly, assuming that there is not doubt as to the proper viewable/usable pixel dimensions of my file, is a clap even necessary ?

  


• Can I record a video without using UIImagePickerController ?

  24 mai 2016, par SUKIYAKI

  Can I record a video without using UIImagePickerController ?
  Of course without needing to jailbreak or anything else that would cause the App Store to reject the app.

  I think there is a way to access video device not using UIImagePickerController because these camera applications can record video and work on iPhone 2G/3G which utilizes ffmpeg :

  • iVideoCamera
  • iVidCam

  I pick this code up by googling.

  AVFormatParameters formatParams;
  
  AVInputFormat *iformat;
  
  
  
  formatParams.device = "/dev/video0";
  
  formatParams.channel = 0;
  
  formatParams.standard = "ntsc";
  
  formatParams.width = 640;
  
  formatParams.height = 480;
  
  formatParams.frame_rate = 29;
  
  formatParams.frame_rate_base = 1;
  
  filename = "";
  
  iformat = av_find_input_format("video4linux");
  
  
  
  av_open_input_file(&ffmpegFormatContext,
  
                   filename, iformat, 0, &formatParams);

  This code tell me how to open camera device, but I don’t know device path of iPhone.

  How do iVideoCamera and iVidCam record video ?

• Converting .mov to .m3u8 with ffmpeg

  22 avril 2015, par Tim Baker

  I’m trying to convert a file to get it ready for adapative streaming. Have a .mov file I’d like to make .m3u8

  Using ffmpeg, but I’ll admit I’m not completely familiar with the process.

  ffmpeg -i intro.mov -c:v libx264 -b:a 32k -c:a aac -strict -f segment.ts -segment_list playlist.m3u8 

  I’m getting the following error :

  Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height

      Stream #0:0(eng): Video: h264, q=2-31, 128 kb/s, 23.98 fps (default)
  
      Metadata:
  
        creation_time   : 2015-04-20 23:58:02
  
        handler_name    : Apple Video Media Handler
  
        encoder         : Lavc55.69.100 libx264
  
      Stream #0:1(eng): Audio: aac, 0 channels, 128 kb/s (default)
  
      Metadata:
  
        creation_time   : 2015-04-20 23:58:02
  
        handler_name    : Apple Sound Media Handler
  
        encoder         : Lavc55.69.100 aac
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
  
    Stream #0:1 -> #0:1 (aac (native) -> aac (native))