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• Patent skullduggery : Tandberg rips off x264 algorithm

  25 novembre 2010, par Dark Shikari — patents, ripoffs, x264

  Update : Tandberg claims they came up with the algorithm independently : to be fair, I can actually believe this to some extent, as I think the algorithm is way too obvious to be patented. Of course, they also claim that the algorithm isn’t actually identical, since they don’t want to lose their patent application.

  I still don’t trust them, but it’s possible it’s merely bad research (and thus being unaware of prior art) as opposed to anything malicious. Furthermore, word from within their office suggests they’re quite possibly being honest : supposedly the development team does not read x264 code at all. So this might just all be very bad luck.

  Regardless, the patent is still complete tripe, and should never have been filed.
  

  Most importantly, stop harassing the guy whose name is on the patent (Lars) : he’s just a programmer, not the management or lawyers responsible for filing the patent. This is stupid and unnecessary. I’ve removed the original post because of this ; it can be found here for those who want to read it.

  Appendix : the details of the patent :

  I figure I’ll go over the exact correspondence between the patent and my code here.

  1. A method for calculating run and level representations of quantized transform coefficients representing pixel values included in a block of a video picture, the method comprising :

  Translation : It’s a run-level coder.

  packing, at a video processing apparatus, each quantized transform coefficients in a value interval [Max, Min] by setting all quantized transform coefficients greater than Max equal to Max, and all quantized transform coefficients less than Min equal to Min

  The quantized coefficients are clipped to a certain valid range to allow them to be packed into bytes (they start as 16-bit values).

  reordering, at the video processing apparatus, the quantized transform ID coefficients according to a predefined order depending on respective positions in the block resulting in an array C of reordered quantized transform coefficients

  This is the zigzag pattern used in H.264 (and most formats) for reordering DCT coefficients. In x264, this is done before the run-level coder ste.

  masking, at the video processing apparatus, C by generating an array M containing ones in positions corresponding to positions of C having non-zero values, and zeros in positions corresponding to positions of C having zero values

  This is creating a bitmask based on the coefficient values, the pmovmskb step.

  is generating, at the video processing apparatus, for each position containing a one in M, a run and a level representation by setting the level value equal to an occurring value in a corresponding position of C ; and setting, at the video processing apparatus, for each position containing a one in M₅ the run value equal to the number of proceeding positions relative to a current position in M since a previous occurrence of one in M.

  This is the process of creating run/level values from the bitmask.

  Now into the detailed claims :

  2. The method according to Claim 1, wherein the masking further includes, creating an array C from C where positions corresponding to positions of nonzero values in C are filled with ones, and positions corresponding to positions of zero values in C are filled with zeros, and creating M from C by extracting the most significant bit from values in respective position of C and inserting the bits in corresponding positions in M.

  They’re extracting the most significant bit of the values to create a bitmask. This is exactly what the pmovmskb in my algorithm does.

  3. The method according to Claim 2, wherein the creating of the array C is executed by a C++ function PCMPGTB, and the creating of M from C is executed by a C++ function PMOVMSKB.

  And here they use pcmpgtb (they call it a C++ function for some reason, but it’s a SSE instruction) to do the clipping of the input values. This is exactly the same method I used in decimate_score. They also use pmovmskb as mentioned.

  4. The method according to Claim 1 , wherein the generating of the run and level representation further includes determining positions containing non-zero values in C by corresponding positions containing ones in M.

  5. The method according to Claim 4, wherein the determining of positions containing non-zero values in C is executed by a C++ function BSF.

  Here they iterate over the bitmask of transform coefficients using a “BSF” function to find runs, which is exactly what I did. Of course, BSF isn’t a function, it’s an x86 instruction.

  6. The method according to Claim 1 , wherein Max is 256 and Min is 0.

  This is almost surely a typo or mistake of some sort. They mean the Max should be 255, not 256 : 256 doesn’t fit in a uint8_t.

  7. The method according to Claim 1 , wherein the predefined order follows a zigzag path of transform coefficient positions in the block starting in an upper left corner heading towards a lower right corner.

  This is a description of the typical DCT zigzag pattern (like in H.264, MPEG-2, Theora, etc).

  Everything after this part is just repeating itself with the phrase “an apparatus” added in order to make the USPTO listen to them.

• Picturebox from AForge FFMPEG empty - C#/WinForms

  1er août 2017, par Jake Delson

  I’ve done a ton of research and looked at a lot of questions here but can’t seem to find anything to help me. I should preface I’m very new to C#, Windows Forms, and SO ! I’m a 1st year CompSci student coming from C++ experimenting with my own projects for the summer. I’m trying to display a series of bitmaps from a .avi using the AForge.Video.FFMPEG video file reader.

  It seems to be finding the file, getting its’ data (console prints dimensions, framerate, and codec) and creating the picturebox, but the picturebox comes up blank/empty. I get the bitmap from the frames of a .avi :

  From AForge example code here

  Then I’m trying to display it with a picture box :

  From MS example code here as well

  And here’s my code. Essentially a combination of the two :

      public class Simple : Form
  
  {
  
      Bitmap videoFrame;
  
  
  
      public Simple()
  
      {
  
          try
  
          {
  
              // create instance of video reader
  
              VideoFileReader reader = new VideoFileReader();
  
              // open video file
  
              reader.Open(@"C:\Users\User\Desktop\ScanTest3.AVI");
  
              // check some of its attributes
  
              Console.WriteLine("width:  " + reader.Width);
  
              Console.WriteLine("height: " + reader.Height);
  
              Console.WriteLine("fps:    " + reader.FrameRate);
  
              Console.WriteLine("codec:  " + reader.CodecName);
  
  
  
              PictureBox pictureBox1 = new PictureBox();
  
  
  
              // read 100 video frames out of it
  
              for (int i = 0; i < 100; i++)
  
              {
  
                  videoFrame = reader.ReadVideoFrame();
  
  
  
                  pictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;
  
                  pictureBox1.ClientSize = new Size(videoFrame.Width, videoFrame.Height);
  
                  pictureBox1.Image = videoFrame;
  
  
  
                  // dispose the frame when it is no longer required
  
                  videoFrame.Dispose();
  
              }
  
  
  
              reader.Close();
  
          }
  
  
  
          catch
  
          {
  
              Console.WriteLine("Nope");
  
          }
  
  
  
      }
  
  }
  
  
  
  class MApplication
  
  {
  
      public static void Main()
  
      {
  
          Application.Run(new Simple());
  
      }
  
  }

  So that’s it pretty much. Just a blank picture box coming up, when it should have the first frame of the video, even though no exception caught (though I’m pretty confident I’m using the try/catch very poorly), and the console printing the correct data for the file :

  width:  720
  
  height: 480
  
  fps:    29
  
  codec:  dvvideo
  
  [swscaler @ 05E10060] Warning: data is not aligned! This can lead to a speedloss

  Though if anyone could tell me what that warning means, that would be great as well, but I’m mainly just lost as to why there’s no picture printing to the screen.

  Thanks !

• AFTER PHP-FFMpeg not converting (error with ffmpeg)

  15 juin 2018, par Magurean Dan Sergiu

  I have installed ffmpeg server side with all the dependencies, updated it. And then installed PHP-FFMpeg with Composer. Tested that ffmpeg is instaled with a ssh conexion.

  root@host [/opt/ffmpeg]# ffmpeg
  
  ffmpeg version N-81322-ge8b355a Copyright (c) 2000-2016 the FFmpeg developers
  
  built with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-17)
  
  configuration: --disable-yasm
  
  libavutil      55. 28.100 / 55. 28.100
  
  libavcodec     57. 51.100 / 57. 51.100
  
  libavformat    57. 46.100 / 57. 46.100
  
  libavdevice    57.  0.102 / 57.  0.102
  
  libavfilter     6. 51.100 /  6. 51.100
  
  libswscale      4.  1.100 /  4.  1.100
  
  libswresample   2.  1.100 /  2.  1.100
  
  Hyper fast Audio and Video encoder
  
  usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options]     outfile}...
  
  
  
  Use -h to get full help or, even better, run 'man ffmpeg'

  But when I try to convert a video file with a php script it throws me a very long error.
  PHP Code :

  <?PHP
  
  include($_SERVER['DOCUMENT_ROOT']."/vendors/install/vendor/autoload.php");
  
  $ffmpeg = FFMpeg\FFMpeg::create();
  
  $video = $ffmpeg->open($_SERVER['DOCUMENT_ROOT'].'/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.wmv');
  
  $video
  
         ->filters()
  
         ->synchronize();
  
  $format = new FFMpeg\Format\Video\X264();
  
  $format->on('progress', function ($video, $format, $percentage) {
  
      echo "$percentage % transcoded";});
  
  $video
  
        ->save($format,$_SERVER['DOCUMENT_ROOT'].'/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.mp4');
  
  ?>

  Error displayed :

  <b>Fatal error</b>:  Uncaught exception 'Alchemy\BinaryDriver\Exception\ExecutionFailureException' with message 'ffmpeg failed to execute command '/usr/local/bin/ffmpeg' '-y' '-i' '/home/user/working/resources/uploads/23097/2efeb41a1a7085a1dbd469c4895ac23e.wmv' '-async' '1' '-metadata:s:v:0' 'start_time=0' '-threads' '12' '-vcodec' 'libx264' '-acodec' 'libfaac' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '128k' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes57ad320a1b685j794u/pass-57ad320a1b716' '/home/user/working/resources/uploads/23097/2efeb41a1a7085a1dbd469c4895ac23e.mp4'' in /home/user/working/vendors/install/vendor/alchemy/binary-driver/src/Alchemy/BinaryDriver/ProcessRunner.php:100↵Stack trace:↵#0 /home/user/working/vendors/install/vendor/alchemy/binary-driver/src/Alchemy/BinaryDriver/ProcessRunner.php(72): Alchemy\BinaryDriver\ProcessRunner-&amp;gt;doExecutionFailure(''/usr/bin/ffmpe...')↵#1 / in <b>/home/user/working/vendors/install/vendor/php-ffmpeg/php-ffmpeg/src/FFMpeg/Media/Video.php</b> on line <b>168</b><br />↵"

  Then I have took the basic code displayed upwards and ran it directly through ssh.

  '/usr/local/bin/ffmpeg' '-y' '-i' '/home/user/working/resources/uploads/23097/2efeb41a1a7085a1dbd469c4895ac23e.wmv' '-async' '1' '-metadata:s:v:0' 'start_time=0' '-threads' '12' '-vcodec' 'libx264' '-acodec' 'libfaac' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '128k' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes57ad320a1b685j794u/pass-57ad320a1b716' '/home/user/working/resources/uploads/23097/2efeb41a1a7085a1dbd469c4895ac23e.mp4'

  And this is the response I get :

  ffmpeg version N-81322-ge8b355a Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 4.4.7 (GCC) 20120313 (Red Hat 4.4.7-17)
  
    configuration: --disable-yasm
  
    libavutil      55. 28.100 / 55. 28.100
  
    libavcodec     57. 51.100 / 57. 51.100
  
    libavformat    57. 46.100 / 57. 46.100
  
    libavdevice    57.  0.102 / 57.  0.102
  
    libavfilter     6. 51.100 /  6. 51.100
  
    libswscale      4.  1.100 /  4.  1.100
  
    libswresample   2.  1.100 /  2.  1.100
  
  Guessed Channel Layout for Input Stream #0.0 : stereo
  
  Input #0, asf, from '/home/user/working/resources/uploads/23097/2efeb41a1a7085a1dbd469c4895ac23e.wmv':
  
    Metadata:
  
      SfOriginalFPS   : 299700
  
      WMFSDKVersion   : 11.0.6001.7000
  
      WMFSDKNeeded    : 0.0.0.0000
  
      comment         : Footage: Small World Productions, Inc; Tourism New Zealand | Producer: Gary F. Spradling | Music: Steve Ball
  
      title           : Wildlife in HD
  
      copyright       : © 2008 Microsoft Corporation
  
      IsVBR           : 0
  
      DeviceConformanceTemplate: AP@L3
  
    Duration: 00:00:30.09, start: 0.000000, bitrate: 6977 kb/s
  
      Stream #0:0(eng): Audio: wmav2 (a[1][0][0] / 0x0161), 44100 Hz, 2 channels, fltp, 192 kb/s
  
      Stream #0:1(eng): Video: vc1 (Advanced) (WVC1 / 0x31435657), yuv420p, 1280x720, 5942 kb/s, 29.97 fps, 29.97 tbr, 1k tbn, 1k tbc
  
  Unknown encoder 'libx264'

  My question is what to do next ? I have wasted 3 days to make this work and this is the furthest I have come. How can I test if libx264 is installed corectly ? And if it is not installed corectly how cand I reinstal or make it work ?

  After a few modifications

  I have used an already installed ffmpeg, and removed a few commands (that were by default the same) and this time I used only the command line.

  The request

  '/home/user/working/vendors/install/ffmpeg-git-20160813-64bit-static/ffmpeg' '-y' '-i' '/home/user/working/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.wmv' '-async' '1' '-metadata:s:v:0' 'start_time=0' '-vcodec' 'libx264' '-c:a' 'aac' '-b:v' '1000k' '-b:a' '128k' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes57b053ce14a12ljm8a/pass-57b053ce14ad3' '/home/user/working/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.mp4'

  The new result :

  ffmpeg version N-81328-gceab04f-static http://johnvansickle.com/ffmpeg/  Copyright (c) 2000-2016 the FFmpeg developers
  
    built with gcc 5.4.1 (Debian 5.4.1-1) 20160803
  
    configuration: --enable-gpl --enable-version3 --enable-static --disable-debug --enable-libmp3lame --enable-libx264 --enable-libx265 --enable-libwebp --enable-libspeex --enable-libvorbis --enable-libvpx --enable-libfreetype --enable-fontconfig --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libtheora --enable-libvo-amrwbenc --enable-gray --enable-libopenjpeg --enable-libopus --enable-libass --enable-gnutls --enable-libvidstab --enable-libsoxr --enable-frei0r --enable-libfribidi --disable-indev=sndio --disable-outdev=sndio --enable-librtmp --enable-libmfx --enable-libzimg --cc=gcc-5
  
    libavutil      55. 28.100 / 55. 28.100
  
    libavcodec     57. 51.102 / 57. 51.102
  
    libavformat    57. 46.101 / 57. 46.101
  
    libavdevice    57.  0.102 / 57.  0.102
  
    libavfilter     6. 51.100 /  6. 51.100
  
    libswscale      4.  1.100 /  4.  1.100
  
    libswresample   2.  1.100 /  2.  1.100
  
    libpostproc    54.  0.100 / 54.  0.100
  
  Guessed Channel Layout for Input Stream #0.0 : stereo
  
  Input #0, asf, from '/home/user/working/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.wmv':
  
    Metadata:
  
      SfOriginalFPS   : 299700
  
      WMFSDKVersion   : 11.0.6001.7000
  
      WMFSDKNeeded    : 0.0.0.0000
  
      comment         : Footage: Small World Productions, Inc; Tourism New Zealand | Producer: Gary F. Spradling | Music: Steve Ball
  
      title           : Wildlife in HD
  
      copyright       : © 2008 Microsoft Corporation
  
      IsVBR           : 0
  
      DeviceConformanceTemplate: AP@L3
  
    Duration: 00:00:30.09, start: 0.000000, bitrate: 6977 kb/s
  
      Stream #0:0(eng): Audio: wmav2 (a[1][0][0] / 0x0161), 44100 Hz, 2 channels, fltp, 192 kb/s
  
      Stream #0:1(eng): Video: vc1 (Advanced) (WVC1 / 0x31435657), yuv420p, 1280x720, 5942 kb/s, 29.97 fps, 29.97 tbr, 1k tbn, 1k tbc
  
  -async is forwarded to lavfi similarly to -af aresample=async=1:min_hard_comp=0.100000:first_pts=0.
  
  [libx264 @ 0x442f5c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 AVX2 LZCNT BMI2
  
  [libx264 @ 0x442f5c0] ratecontrol_init: can't open stats file
  
  Output #0, mp4, to '/home/user/working/resources/uploads/96048/ffd3c5e349fa5745159deef163b5c253.mp4':
  
    Metadata:
  
      SfOriginalFPS   : 299700
  
      WMFSDKVersion   : 11.0.6001.7000
  
      WMFSDKNeeded    : 0.0.0.0000
  
      comment         : Footage: Small World Productions, Inc; Tourism New Zealand | Producer: Gary F. Spradling | Music: Steve Ball
  
      title           : Wildlife in HD
  
      copyright       : © 2008 Microsoft Corporation
  
      IsVBR           : 0
  
      DeviceConformanceTemplate: AP@L3
  
      Stream #0:0(eng): Unknown: none
  
      Metadata:
  
        start_time      : 0
  
        encoder         : Lavc57.51.102 libx264
  
      Stream #0:1(eng): Unknown: none
  
      Metadata:
  
        encoder         : Lavc57.51.102 aac
  
  Stream mapping:
  
    Stream #0:1 -> #0:0 (vc1 (native) -> h264 (libx264))
  
    Stream #0:0 -> #0:1 (wmav2 (native) -> aac (native))
  
  Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height