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• Decoding RIMM streaming file format

  10 septembre 2011, par Thomas

  I want to decode the video (visual) frames within a Blackberry RIMM file. So far I have a parser, and some corresponding container documentation from RIM. 

  The video codec is H264 and is explicitly set on the device using one of the video.encodings properties. However, FFMPEG is not able to decode the frames and this is driving me nuts.

  Edit 1 : The issues seems to be lack of SPS and PPS in the frames, and artificially inserting them have proven unsuccessful so far (all grey image). Blackberry 9700 sends

  0x00 0x00 0x ?? 0x ?? 0xType

  where Type is according to table 7-1 in the H264 spec (I and P frames). We believe the 0x ?? 0x ?? represent the size of the frame, however the size does not always correspond to the size found by the parser (the parser seems to be working correctly).

  I have a windows decoder codec from blackberry, called mc_demux_mp2_ds.ax, and can play some MPEG-4 files captured the same way, but it is a binary for windows. And the H264 files will not play either way. I am aware of previous attempts. The capture url for javax.microedition.media.Manager is

  encoding=video-3gpp_width=176_height=144_video_codec=H264_audio_codec=AAC

  and I am writing to an output stream. Some example files here.

  Edit 2 :Turns out that about 3-4 of the 12-15 available video capture modes are flat out failing and refusing to output data, even in the simplest of test applications. So any working solution should implement MPEG-4, H264 and H263 in both AMR and AAC, in so getting fallback alternatives when one sound codec and/or resolution fails. Reboots, hangs and what not litters the Blackberry video implementation and vary from firmware to firmware ; total suckage.

• Revision 683b5a3161 : vpx_subpixel_8t_ssse3 : fix reg counts/access fixes build on windows x64 ; previo

  17 septembre 2015, par James Zern

  Changed Paths :
   Modify /vpx_dsp/x86/vpx_subpixel_8t_ssse3.asm

  
  
  vpx_subpixel_8t_ssse3 : fix reg counts/access

  fixes build on windows x64 ; previously ’heightq’ i.e., the 64-bit register
  was accessed when only the 32-bit value was needed. given this is from a
  stack variable the upper bits were undefined.

  + bump register/xmm counts ; users of SETUP_LOCAL_VARS touch xmm13 in
  64-bit builds and filter_block1d16_v* uses one extra temp variable

  Change-Id : I9c768c0b2047481d1d3b11c2e16b2f8de6eb0d80

• Using FFMPEG to reliably convert videos to mp4 for iphone/ipod and flash players

  23 avril 2016, par Jake Stevenson

  I need to convert videos for use in both a flash player and the iphone/ipod touch. I’m using the following batch script with ffmpeg :

  @echo off
  
  ffmpeg.exe -i %1 -s qvga -acodec libfaac -ar 22050 -ab 128k -vcodec libx264 -threads 0 -f ipod %2

  This always outputs an mp4 file, and I can always play it on my PC. The videos also seem to play fine on my iphone 3GS. But with some input files it won’t work for older iphone versions (3G and iPod touch).

  Here’s the ffmpeg output from one such file :

  D:\ffmpeg>encode.bat d:\temp\recording.flv d:\temp\out.m4v
  
  FFmpeg version SVN-r18709, Copyright (c) 2000-2009 Fabrice Bellard, et al.
  
    configuration: --enable-memalign-hack --prefix=/mingw --cross-prefix=i686-ming
  
  w32- --cc=ccache-i686-mingw32-gcc --target-os=mingw32 --arch=i686 --cpu=i686 --e
  
  nable-avisynth --enable-gpl --enable-zlib --enable-bzlib --enable-libgsm --enabl
  
  e-libfaac --enable-libfaad --enable-pthreads --enable-libvorbis --enable-libtheo
  
  ra --enable-libspeex --enable-libmp3lame --enable-libopenjpeg --enable-libxvid -
  
  -enable-libschroedinger --enable-libx264
  
    libavutil     50. 3. 0 / 50. 3. 0
  
    libavcodec    52.27. 0 / 52.27. 0
  
    libavformat   52.32. 0 / 52.32. 0
  
    libavdevice   52. 2. 0 / 52. 2. 0
  
    libswscale     0. 7. 1 /  0. 7. 1
  
    built on Apr 28 2009 04:04:42, gcc: 4.2.4
  
  [flv @ 0x187d650]skipping flv packet: type 18, size 164, flags 0
  
  Input #0, flv, from 'd:\temp\recording.flv':
  
    Duration: 00:00:07.17, start: 0.001000, bitrate: N/A
  
      Stream #0.0: Video: flv, yuv420p, 320x240, 1k tbr, 1k tbn, 1k tbc
  
      Stream #0.1: Audio: nellymoser, 44100 Hz, mono, s16
  
  [libx264 @ 0x13518b0]using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE
  
  4.2
  
  [libx264 @ 0x13518b0]profile Baseline, level 4.2
  
  Output #0, ipod, to 'd:\temp\out.m4v':
  
      Stream #0.0: Video: libx264, yuv420p, 320x240, q=2-31, 200 kb/s, 1k tbn, 1k
  
  tbc
  
      Stream #0.1: Audio: libfaac, 22050 Hz, mono, s16, 128 kb/s
  
  Stream mapping:
  
    Stream #0.0 -> #0.0
  
    Stream #0.1 -> #0.1
  
  Press [q] to stop encoding
  
  frame=   90 fps=  0 q=-1.0 Lsize=     128kB time=6.87 bitrate= 152.4kbits/s
  
  video:92kB audio:32kB global headers:1kB muxing overhead 2.620892%
  
  [libx264 @ 0x13518b0]slice I:8     Avg QP:29.62  size:  7047
  
  [libx264 @ 0x13518b0]slice P:82    Avg QP:30.83  size:   467
  
  [libx264 @ 0x13518b0]mb I  I16..4: 17.9%  0.0% 82.1%
  
  [libx264 @ 0x13518b0]mb P  I16..4:  0.6%  0.0%  0.0%  P16..4: 23.1%  0.0%  0.0%
  
   0.0%  0.0%    skip:76.3%
  
  [libx264 @ 0x13518b0]final ratefactor: 57.50
  
  [libx264 @ 0x13518b0]SSIM Mean Y:0.9544735
  
  [libx264 @ 0x13518b0]kb/s:8412.6

  My suspicion is that it has something to do with the audio encoding. If so, does anyone know how to force it to reencode the audio to the proper format ?

  Any other ideas ?