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• Revision 99c4b1eea1 : Replace default counts with default probs. Replace vp9_kf_default_bmode_counts

  16 mai 2013, par Paul Wilkins

  Changed Paths :
   Modify /vp9/common/vp9_entropymode.c

  
   Modify /vp9/common/vp9_entropymode.h

  
   Modify /vp9/common/vp9_modecontext.c

  
   Modify /vp9/encoder/vp9_bitstream.c

  
  
  Replace default counts with default probs.

  Replace vp9_kf_default_bmode_counts structure with
  direct default probabilities. The probability structure is
  smaller and it removes the need to specify in the bitstream
  how to convert the counts to probabilities.

  Note that I have concerns still about the size and value of
  the large intra mode context. This may cause problems for
  HW but it also means we rely heavily on reverse update as
  forwards update of a structure this size is problematic. I
  intend to review this more generally in the next few days to
  see if we can come up with a competitive solution that does
  not rely on such a large context.

  Change-Id : I0a36071079d5d26a57ab0e9fbf91af4199aa7984

• .mov conversion to .mp4 using ffmpeg doesn't convert the entire video

  5 février 2013, par user504879

  I am trying to convert a mov file which I got from saving my powerpoint presentation to a movie file. However only a part of the presentation is converted not the entire one and also running qt-start doesn't make the exported mp4 to stream over rtmp. Is there something which I am missing ?

  I am attaching the output which i get when I am trying to convert the file using ffmpeg

  $ export LD_LIBRARY_PATH=/usr/local/lib; /usr/local/bin/ffmpeg -y -i /data/tmp/vialogues_prez.mov -r 20 -g 40 -acodec libfaac -ar 44100  -ab 96k -vcodec libx264 -s 640x480 -vpre medium /data/videos/vialogues_prez.mp4
  
  
  
  FFmpeg version 0.6.1, Copyright (c) 2000-2010 the FFmpeg developers
  
    built on Feb 19 2011 19:03:56 with gcc 4.4.5
  
    configuration: --enable-gpl --enable-version3 --enable-nonfree --enable-postproc --enable-libfaac --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libxvid --enable-x11grab
  
    libavutil     50.15. 1 / 50.15. 1
  
    libavcodec    52.72. 2 / 52.72. 2
  
    libavformat   52.64. 2 / 52.64. 2
  
    libavdevice   52. 2. 0 / 52. 2. 0
  
    libswscale     0.11. 0 /  0.11. 0
  
    libpostproc   51. 2. 0 / 51. 2. 0
  
  [mov,mp4,m4a,3gp,3g2,mj2 @ 0x186f460]max_analyze_duration reached
  
  
  
  Seems stream 0 codec frame rate differs from container frame rate: 600.00 (600/1) -> 0.08 (1/12)
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/data/tmp/vialogues_prez.mov':
  
    Metadata:
  
      major_brand     : qt  
  
      minor_version   : 537199360
  
      compatible_brands: qt  
  
      comment         : Microsoft PowerPoint Movie
  
      comment-eng     : Microsoft PowerPoint Movie
  
    Duration: 00:04:47.00, start: 0.000000, bitrate: 22 kb/s
  
      Stream #0.0(eng): Video: qtrle, bgra, 640x480, 21 kb/s, 0.01 fps, 0.08 tbr, 600 tbn, 600 tbc
  
      Stream #0.1(eng): Video: 0x0000, 600 tbr, 600 tbn, 600 tbc
  
      Stream #0.2(eng): Video: 0x0000, 600 tbr, 600 tbn, 600 tbc
  
  [libx264 @ 0x1873b50]using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE4.1 Cache64
  
  [libx264 @ 0x1873b50]profile High, level 3.0
  
  [libx264 @ 0x1873b50]264 - core 114 - H.264/MPEG-4 AVC codec - Copyleft 2003-2011 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=1 sliced_threads=0 nr=0 decimate=1 interlaced=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=abr mbtree=1 bitrate=200 ratetol=20.0 qcomp=0.60 qpmin=10 qpmax=51 qpstep=4 ip_ratio=1.41 aq=1:1.00
  
  Output #0, mp4, to '/data/videos/vialogues_prez.mp4':
  
    Metadata:
  
      encoder         : Lavf52.64.2
  
      Stream #0.0(eng): Video: libx264, yuv420p, 640x480, q=10-51, 200 kb/s, 20 tbn, 20 tbc
  
  Stream mapping:
  
    Stream #0.0 -> #0.0
  
  Press [q] to stop encoding
  
  frame=    4 fps=  0 q=32766.0 Lsize=      50kB time=45.05 bitrate=   9.0kbits/s    
  
  video:49kB audio:0kB global headers:0kB muxing overhead 1.740573%
  
  [libx264 @ 0x1873b50]frame I:1     Avg QP:32.73  size:  8427
  
  [libx264 @ 0x1873b50]frame P:3     Avg QP:20.68  size: 13640
  
  [libx264 @ 0x1873b50]mb I  I16..4: 60.8% 14.6% 24.7%
  
  [libx264 @ 0x1873b50]mb P  I16..4: 28.7%  7.2% 15.4%  P16..4:  2.0%  1.3%  1.4%  0.0%  0.0%    skip:43.9%
  
  [libx264 @ 0x1873b50]final ratefactor: -16.67
  
  [libx264 @ 0x1873b50]8x8 transform intra:14.2% inter:5.0%
  
  [libx264 @ 0x1873b50]coded y,uvDC,uvAC intra: 25.2% 18.4% 13.0% inter: 5.3% 7.4% 7.2%
  
  [libx264 @ 0x1873b50]i16 v,h,dc,p: 63% 34%  1%  2%
  
  [libx264 @ 0x1873b50]i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 19% 41% 31%  1%  1%  1%  1%  1%  4%
  
  [libx264 @ 0x1873b50]i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 29% 33% 19%  2%  3%  3%  4%  3%  4%
  
  [libx264 @ 0x1873b50]i8c dc,h,v,p: 75% 20%  4%  1%
  
  [libx264 @ 0x1873b50]Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0x1873b50]ref P L0: 57.0% 12.2% 26.2%  4.7%
  
  [libx264 @ 0x1873b50]kb/s:1.14

  any help is appreciated.

• find out if file is a video or an image with ffmpeg

  4 juin 2014, par Pavel K.

  is there any direct way of finding out whether file is an image or video while using ffmpeg library ?

  i know i can get codec_id from AVCodecContext (https://www.ffmpeg.org/doxygen/trunk/structAVCodecContext.html), but enumeration at https://www.ffmpeg.org/doxygen/trunk/group__lavc__core.html#gaadca229ad2c20e060a14fec08a5cc7ce

  is really huge and doesnt seem to be categorized..