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• Revision db2b350d33: Declare setup_buffer_inter in vp9_rdopt.h This funtion initializes buffer point

  10 January 2014, by Jingning Han

  Changed Paths:
   Modify /vp9/encoder/vp9_rdopt.c

  
   Modify /vp9/encoder/vp9_rdopt.h

  
  
  Declare setup_buffer_inter in vp9_rdopt.h

  This funtion initializes buffer pointers and first stage motion vector
  prediction. It will be needed by both regular rate-distortion
  optimization loop and the non-RD mode decision. Hence move its
  declaration in vp9_rdopt.h

  Change-Id: I64e8b6316c9d05f20756a62721533a2e4d158235

• Converting RGB to YUV, + ffmpeg

  10 July 2012, by TheSHEEEP

  I am trying the following to record a live video from my Flash/AIR application:

  1. I take a "screenshot" (BitmapData from stage) each frame.

  2. I convert each pixel to yuv format like this (V2):

         var file :File = new File(_appUrl + "/creation/output.raw");
     
         var fs :FileStream = new FileStream();
     
         fs.open(file, FileMode.WRITE);
     
         var finalY :ByteArray = new ByteArray();
     
         var finalU :ByteArray = new ByteArray();
     
         var finalV :ByteArray = new ByteArray();
     
         var rect :Rectangle = new Rectangle(0, 0, 600, 700);
     
         var pixels :ByteArray;
     
         var pixel :uint;
     
         var r :uint;
     
         var g :uint;
     
         var b :uint;
     
         _screenBuffer = _screenBuffer.reverse();
     
         while (_screenBuffer.length > 0)
     
         {
     
             pixels = BitmapData(_screenBuffer.pop()).getPixels(rect);
     
             pixels.position = 0;
     
             // Convert and save each pixel
     
             for (var x:int = 0; x < 600; x++)
     
             {
     
                 for (var y:int = 0; y < 700; y++)
     
                 {
     
                     // Convert to yuv
     
                     pixel = pixels.readUnsignedInt();
     
                     r = pixel >> 16 & 0xff;
     
                     g = pixel >> 8 & 0xff;
     
                     b = pixel & 0xff;
     
                         // Y' is written for each pixel
     
                     finalY.writeByte(0.257 * r + 0.504 * g + 0.098 * b + 128);
     
                         // U and V are written once per 2x2 pixel block
     
                     if (x % 2 == 0 && y % 2 == 0)
     
                     {
     
                         finalU.writeByte(-0.148 * r - 0.291 * g + 0.439 * b + 128);
     
                         finalV.writeByte(0.439 * r - 0.368 * g - 0.071 * b + 128);
     
                     }
     
                 }
     
             }
     
         }
     
         // Write the converted bytes to the file
     
         finalY.position = 0;
     
         finalU.position = 0;
     
         finalV.position = 0;
     
         fs.writeBytes(finalY, 0, finalY.length);
     
         fs.writeBytes(finalU, 0, finalU.length);
     
         fs.writeBytes(finalV, 0, finalV.length);
     
         fs.close();

  3. I use the following line of ffmpeg to convert the raw file to a video:

     ffmpeg -r 30 -pix_fmt yuv420p -s 600x700 -vcodec rawvideo -f rawvideo -i output.raw -y test.mp4 

  A video is created, but it is simply a mess, barely resembling what was recorded. I know that the capturing process works, as I have tried the same BitmapData "screenshots" with the SimpleFlvWriter.

  So, either something is wrong with my conversion or with the ffmpeg line, but I have no idea.

  This is what ffmpeg outputs when creating the video, maybe it can help someone:

  libavutil      51. 39.100 / 51. 39.100
  
  libavcodec     54.  3.101 / 54.  3.101
  
  libavformat    54.  1.100 / 54.  1.100
  
  libavdevice    53.  4.100 / 53.  4.100
  
  libavfilter     2. 62.101 /  2. 62.101
  
  libswscale      2.  1.100 /  2.  1.100
  
  libswresample   0.  7.100 /  0.  7.100
  
  libpostproc    52.  0.100 / 52.  0.100
  
  [rawvideo @ 01D39FC0] Estimating duration from bitrate, this may be inaccurate
  
  Input #0, rawvideo, from 'output.raw':
  
    Duration: N/A, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 600x700, 30 tbr,
  
  30 tbn, 30 tbc
  
  [buffer @ 01D3FEC0] w:600 h:700 pixfmt:yuv420p tb:1/1000000 sar:0/1 sws_param:
  
  [libx264 @ 0375DB80] using cpu capabilities: MMX2 SSE2Fast SSSE3 FastShuffle SSE 4.2 AVX
  
  [libx264 @ 0375DB80] profile High, level 3.1
  
  [libx264 @ 0375DB80] 264 - core 120 r2146 bcd41db - 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=12 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=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=0rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69qpstep=4 ip_ratio=1.40 aq=1:1.00
  
  Output #0, mp4, to 'test.mp4':
  
    Metadata:
  
      encoder         : Lavf54.1.100
  
      Stream #0:0: Video: h264 (![0][0][0] / 0x0021), yuv420p, 600x700, q=-1--1, 30 tbn, 30 tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (rawvideo -> libx264)
  
  Press [q] to stop, [?] for help
  
  Truncating packet of size 630000 to 1
  
  frame=   48 fps=  0 q=-1.0 Lsize=     157kB time=00:00:01.53 bitrate= 837.3kbits/s
  
  video:156kB audio:0kB global headers:0kB muxing overhead 0.687626%
  
  [libx264 @ 0375DB80] frame I:3     Avg QP:23.15  size: 23480
  
  [libx264 @ 0375DB80] frame P:38    Avg QP:28.80  size:  2169
  
  [libx264 @ 0375DB80] frame B:7     Avg QP:29.61  size:   833
  
  [libx264 @ 0375DB80] consecutive B-frames: 79.2%  4.2%  0.0% 16.7%
  
  [libx264 @ 0375DB80] mb I  I16..4: 41.4%  6.2% 52.4%
  
  [libx264 @ 0375DB80] mb P  I16..4: 10.6%  3.3%  0.9%  P16..4: 68.4%  1.3%  1.2% 0.0%  0.0%    skip:14.2%
  
  [libx264 @ 0375DB80] mb B  I16..4:  0.0%  0.0%  0.0%  B16..8: 13.3%  2.2%  0.7% direct: 1.9%  skip:81.9%  L0:51.6% L1:47.4% BI: 1.0%
  
  [libx264 @ 0375DB80] 8x8 transform intra:16.7% inter:31.2%
  
  [libx264 @ 0375DB80] coded y,uvDC,uvAC intra: 14.7% 25.5% 22.3% inter: 1.0% 4.1% 3.4%
  
  [libx264 @ 0375DB80] i16 v,h,dc,p: 87% 11%  2%  0%
  
  [libx264 @ 0375DB80] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu:  3% 18% 75%  1%  0%  1%  1% 0%  0%
  
  [libx264 @ 0375DB80] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu:  6% 74% 12%  1%  1%  1%  2% 1%  2%
  
  [libx264 @ 0375DB80] i8c dc,h,v,p: 51% 45%  4%  1%
  
  [libx264 @ 0375DB80] Weighted P-Frames: Y:0.0% UV:0.0%
  
  [libx264 @ 0375DB80] ref P L0:  4.6%  0.4% 94.6%  0.3%
  
  [libx264 @ 0375DB80] ref B L0: 96.0%  4.0%
  
  [libx264 @ 0375DB80] ref B L1: 96.5%  3.5%
  
  [libx264 @ 0375DB80] kb/s:793.39

  I'm not really a codec expert (just starting ;)), so I don't know what to make of most of that.

  Here is a zip that contains one of the frames and the video output. What should be visible is a green smiling pear, without any artifacts. Remember the size is 600x700 and the format yuv420. Best to view such raw image files with irfanview, IMO. Don't mind the noise, its from pushing against my microphone ;)

• Revision 20cf22a128: Enforce effective motion vector search range This commit explicitly enforces th

  21 January 2014, by Jingning Han

  Changed Paths:
   Modify /vp9/encoder/vp9_mcomp.c

  
  
  Enforce effective motion vector search range

  This commit explicitly enforces the effective motion vector range
  in the motion search stage. The range needs to be the intersection
  of UMV border, effective absolute motion vector value range, and
  the target search area.

  Change-Id: I1cf7c563e02b1086040dad6c1f4f6be1538635a6