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• 32BGRA to AVFrame(ffmpeg) and viceversa ? for IOS

  8 février 2012, par Asta ni enohpi

  Am working Video Processing in IOS(iphone/ipod/ipad) Using Objective c. i am using AVFoundation Framework to Capture Video . i want to Encode/decode those video frame using ffmpeg-libx264. i have compiled ffmpeg-x264 lib for ios. i got kCVPixelFormatType_32BGRA from AVFoundation.

  my problem is
  1.How to convert kCVPixelFormatType_32BGRA to AVFrame for enode using avcodec_encode_video ?

  2.How to convert AVFrame to kCVPixelFormatType_32BGRA @ decode side from avcodec_decode_video2 ?

  Please help me to start above process or give path for working tutorial .Thanks in advance.

• HTTP Live streaming iOS not refreshing the index .m3u8 file

  27 février 2013, par Emerson Fittipaldi

  I searched all similar questions on StackOverflow, but found none to answer my problem.

  I am trying to stream some movies from my Linux computer (openSuSE 12.1) to my iPad. I convert them with ffmpeg, segment them with my own segmenter, place them in the www folder of my apache2 server and also place inside the .m3u8 playlist. Til here - all is ok !

  I start playing the movie (HTML page with tag) and it plays nicely, but only the first five segments, which have been loaded with the first load of the playlist. The HTML page (the browser, or the player - no idea) does not refresh (re-download) the playlist from the server. Here is what my .m3u8 playlist file looks like :

  #EXTM3U
  
  #EXT-X-MEDIA-SEQUENCE:19
  
  #EXT-X-TARGETDURATION:8
  
  
  
  #EXTINF:8,
  
  http://192.168.1.4/segment_19.ts
  
  #EXTINF:8,
  
  http://192.168.1.4/segment_20.ts
  
  #EXTINF:8,
  
  http://192.168.1.4/segment_21.ts
  
  #EXTINF:8,
  
  http://192.168.1.4/segment_22.ts
  
  #EXTINF:8,
  
  http://192.168.1.4/segment_23.ts

  Segments are in the same folder as the playlist file, segments are correctly encoded (because I can see at least the first five ones :D). I also watch the access_log from the apache server and I see the first load of the playlist, then the consequent load of all 5 segments and it stops till there. It doesn't even try to further refresh the m3u8 file.

  If it matters - iOS 5.0, iPad 2, Wi-Fi version only, not jailbroken

  Ideas ? What am I doing wrong ?

• ffmpeg resize down larger video to fit desired size and add padding

  5 février 2017, par misterjinx

  I’m trying to resize a larger video to fit an area that I have. In order to achieve this I calculate first the dimensions of the resized video so That it fits my area, and then I try to add padding to this video so that the final result will have the desired dimension, keeping the aspect ratio as well.

  So let’s say that I have the original video dimensions of 1280x720 and to fit my area of 405x320 I need first to resize the video to 405x227. I do that. Everything is fine at this point. I do some math and I find out that I have to add 46 pixels of padding at the top and the bottom.

  So the padding parameter of the command for that would be -vf "pad=405:320:0:46:black". But each time I run the command I get an error like Input area 0:46:405:273 not within the padded area 0:0:404:226.

  The only docs for padding that I found is this http://ffmpeg.org/libavfilter.html#pad.

  I don’t know what I’m doing wrong. Anyone had this problem before ? Do you have any suggestions ?