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• extracting single frame from MediaElemet or FFmpegInterop

  13 janvier 2016, par Jakub Wisniewski

  I am writing app (Windows Phone 8.1 Store App) that allows user to connect to IP Camera. I am using FFmpeg Interop library for ffmpeg which allows me to play eg. rtsp streams in media element. I need now a way to somehow extract a single frame from stream or from media element.

  I have tested other application wchih allows connecting to IP cameras - IP Centcom, and they have working snapshots only for mjpeg streams as far as I now (they were not working for rtsp). Becouse of that I belive that it is impossible or at very least very hard to export frame from media element.

  I have different question - if anyone has ever used FFmpeg Interop and would like to help/explain me how could I modify/extend FFmpegInteropMSS to add method called ’GetThumbnailForStream’ that would work similary to ’GetMediaStreamSource’ but would return single frame (bitmap or jpg) instead of MediaStreamSource ?

  Every help would be appreciated

  EDIT :

  I have found something ;

  in MediaSampleProvider in method WriteAVPacketToStream (line 123) there is line

  auto aBuffer = ref new Platform::Array(avPacket->data, avPacket->size);

  and I belive that this is the place that stores single frame data that is needed to convert into bitmap - now since I do not know c++ too much I have a question : how can I convert it into a form that I could return via public method ?

  When returning :

  Platform::Array^

  I get

  ’FFmpegInterop::MediaSampleProvider’ : a non-value type cannot have any public data members

  EDIT2 :

  Ok I am doing approprate projection to byte according to this microsoft information, now I need to check if this is correct data.

• How to build ffmpeg executable binary for Android ?

  22 février 2016, par Én Xinh Lung Linh

  I’m struggling how to build an executable binary of ffmpeg for Android command.
  I am very new to ffmpeg which I need to extract audio from video files such as mp4.

  I followed a tutorial here to build ffmpeg binary : http://www.roman10.net/how-to-build-ffmpeg-for-android/

  I dont need *.so file to use in NDK but only an executable binary.

  I tried to enable : --enable-ffmpeg in shell script build. It yielded a ffmpeg file too. Especially, the file size is small with around 2M. However, I am unable to use it in android execution as following :

  p = Runtime.getRuntime().exec("/data/data/example/ffmpeg -i /sdcard/test.mp4  -vn -acodec copy /sdcard/test.aac");

  The above executed very quickly and of course it didn’t give any result.

  I continued searching and found an example here : https://github.com/guardianproject/android-ffmpeg-java

  The ffmpeg binary in the project is nice, I can run some command with desired output. However, some conversions to mp3 format gets failed because probably it lacked libmp3lame when building. Specially, ffmpeg is heavier than mine quite much, it is about 15M. I don’t know how they build the binayr.

  I’m looking for is a proper guide which I can build with arbitrary options such as libmp3lame, libshine. I get stuck at m4a to mp3 conversion.

  Everybody who has experience in ffmpeg, please guide me. Thank you !

• How to build ffmpeg executable binary for Android ?

  30 septembre 2022, par Uni

  I'm struggling how to build an executable binary of ffmpeg for Android command. I need to extract audio from video files such as mp4.

  


  I followed a tutorial here to build ffmpeg binary : http://www.roman10.net/how-to-build-ffmpeg-for-android/

  


  I dont need *.so file to use in NDK but only an executable binary.

  


  I tried to enable : --enable-ffmpeg in shell script build. It yielded a ffmpeg file too. Especially, the file size is small with around 2M. However, I am unable to use it in android execution as following :

  


  p = Runtime.getRuntime().exec("/data/data/example/ffmpeg -i /sdcard/test.mp4  -vn -acodec copy /sdcard/test.aac");


  


  The above executed very quickly and of course it didn't give any result.

  


  I continued searching and found an example here : https://github.com/guardianproject/android-ffmpeg-java

  


  The ffmpeg binary in the project is nice, I can run some command with desired output. However, some conversions to mp3 format gets failed because probably it lacked libmp3lame when building. Specially, ffmpeg is heavier than mine quite much, it is about 15M. I don't know how they build the binayr.

  


  I'm looking for is a proper guide which I can build with arbitrary options such as libmp3lame, libshine. I get stuck at m4a to mp3 conversion.