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• Extended client ownership of MediaCodec encoder output buffers for RTMP streaming

  13 février 2014, par dbro

  Background:

  I've connected Android's MediaCodec to FFmpeg for muxing a variety of formats not supported by MediaMuxer, including rtmp:// output via a .flv container. Such streaming muxers require longer, unpredictable ownership of MediaCodec's output buffers, as they may perform networking I/O on any packet processing step. For my video stream, I'm using MediaCodec configured for Surface input. To decouple muxing from encoding, I queue MediaCodec's ByteBuffer output buffers to my muxer via a Handler.

  All works splendidly if I mux the .flv output to file, rather than rtmp endpoint.

  Problem:

  When muxing to rtmp://... endpoint I notice my streaming application begins to block on calls to eglSwapBuffers(mEGLDisplay, mEncodingEGLSurface) at dequeueOutputBuffer() once I'm retaining even a few MediaCodec output buffers in my muxing queue as MediaCodec seems to be locked to only 4 output buffers.

  Any tricks to avoid copying all encoder output returned by MediaCodec#dequeueOutputBuffers and immediately calling releaseOutputBuffer(...)?

  The full source of my project is available on Github. Specifically, see:

  • AndroidEncoder.java: Abstract Encoder class with shared behavior between Audio and Video encoders: mainly drainEncoder(). Writes data to a Muxer instance.
  • FFmpegMuxer.java: Implements Muxer
  • CameraEncoder.java. Sends camera frames to an AndroidEncoder subclass configured for Video encoding.

  Systrace

  

  Here's some systrace output streaming 720p @ 2Mbps video to Zencoder.

  Solved

  Copying then releasing the MediaCodec encoder output ByteBuffers as soon as they're available solves the issue without significantly affecting performance. I recycle the ByteBuffer copies in an ArrayDeque for each muxer track, which limits the number of allocations.

• ffmpeg progress status to multiple txt files depending on loglevel values [on hold]

  13 février 2014, par koutzasnew

  When I use this ffmpeg command:

  ffmpeg -i inputVideo.avi -loglevel info -strict -2 outputVideo.mp4 1>progress_output.txt 2>&1
  

  all the progress info goes to progress_output.txt.

  When I use this ffmpeg command:

  ffmpeg -i inputVideo.avi -loglevel fatal -strict -2 outputVideo.mp4 1>error_output.txt 2>&1
  

  all the fatal error info goes to error_output.txt

  Is there a way that I can use ONE ffmpeg command and save:

  1. the -loglevel info information toprogress_output.txt`
  2. the -loglevel fatal information to different error_output.txt

  so, from the progress_output.txt file to check the conversion progress, and from the error_output.txt file to check if a fatal error occurred.

  Is there any other way to do that?

• Is "video:24803kB audio:945kB........." a succesful conversion output line type ? [on hold]

  13 février 2014, par koutzasnew

  I redirect the output of ffmpeg conversions into txt files and I noticed that after multiple line that show the progress of the conversion, for example:

  .....
  .....   
  frame=  867 fps= 18 q=29.0 q=31.0 size=   17846kB time=00:00:28.96 bitrate=5047.6kbits/s    
  frame=  879 fps= 18 q=29.0 q=31.0 size=   18012kB time=00:00:29.36 bitrate=5025.3kbits/s    
  frame=  890 fps= 18 q=29.0 q=31.0 size=   18175kB time=00:00:29.72 bitrate=5008.0kbits/s    
  frame=  900 fps= 18 q=29.0 q=31.0 size=   18429kB time=00:00:30.06 bitrate=5021.8kbits/s    
  frame=  901 fps= 17 q=-1.0 Lq=31.0 size=   20219kB time=00:00:30.14 bitrate=5494.6kbits/s  
  

  it outputs every time a line of this type:

  video:24803kB audio:945kB subtitle:0 global headers:0kB muxing overhead 21.473556%
  

  Could this line be a safe clue to understand that the conversion completed succesfully, or could that line also appear when the conversion fails?

• Separate Audio and Video in android

  13 février 2014, par Manoj

  I am beginner to Android application development,The aim of my project is to separate a audio and video from video file. after surfing in internet i came to know that, using FFmpeg we can do it.

  ffmpeg -i input.mkv # show stream numbers and formats
  ffmpeg -i input.mkv -c copy audio.m4a # AAC
  ffmpeg -i input.mkv -c copy audio.mp3 # MP3
  ffmpeg -i input.mkv -c copy audio.ac3 # AC3
  ffmpeg -i input.mkv -an -c copy video.mkv
  ffmpeg -i input.mkv -map 0:1 -c copy audio.m4a # stream 1
  

  separated video file wouldn't contain any audio it must be contain only video type. whether this option too possible in ffmpeg? is any other alternative option there?.

• is "video:24803kB audio:945kB........." standar succesfull conversion output line type ?

  13 février 2014, par koutzasnew

  I redirect the outputs during ffmpeg conversions into txt files and I noticed that after multiple line that show the progres of the conversion, for example:

  ..... .....
  frame= 867 fps= 18 q=29.0 q=31.0 size= 17846kB time=00:00:28.96 bitrate=5047.6kbits/s
  frame= 879 fps= 18 q=29.0 q=31.0 size= 18012kB time=00:00:29.36 bitrate=5025.3kbits/s
  frame= 890 fps= 18 q=29.0 q=31.0 size= 18175kB time=00:00:29.72 bitrate=5008.0kbits/s
  frame= 900 fps= 18 q=29.0 q=31.0 size= 18429kB time=00:00:30.06 bitrate=5021.8kbits/s
  frame= 901 fps= 17 q=-1.0 Lq=31.0 size= 20219kB time=00:00:30.14 bitrate=5494.6kbits/s

  it outputs every time a line of this type:

  video:24803kB audio:945kB subtitle:0 global headers:0kB muxing overhead 21.473556%

  Could this line be a safe clue to understand that the conversion completed succesfully, or this line type: video:24803kB audio:945kB subtitle:0 global headers:0kB muxing overhead 21.473556%

  could also appear in cases that the conversion fails?

  Thanx!!