Recherche avancée

Sur d’autres sites (6401)

• X264 : How to access NAL units from encoder ?

  18 avril 2014, par user1884325

  When I call

  frame_size = x264_encoder_encode(encoder, &nals, &i_nals, &pic_in, &pic_out);

  and subsequently write each NAL to a file like this :

       if (frame_size >= 0)
  
       {
  
          int i;
  
          int j;
  
  
  
          for (i = 0; i < i_nals; i++)
  
          {
  
             printf("******************* NAL %d (%d bytes) *******************\n", i, nals[i].i_payload);
  
             fwrite(&(nals[i].p_payload[0]), 1, nals[i].i_payload, fid);
  
          }
  
       }

  then I get this

  

  My questions are :

  1) Is it normal that there’s readable parameters in the beginning of the file ?

  2) How do I configure the X264 encoder so that the encoder returns frames that I can send via UDP without the packet getting fragmented (size must be below 1390 or somewhere around that).

  3) With the x264.exe I pass in these options :

  "--threads 1 --profile baseline --level 3.2 --preset ultrafast --bframes 0 --force-cfr --no-mbtree --sync-lookahead 0 --rc-lookahead 0 --keyint 1000 --intra-refresh" 

  How do I map those to the settings in the X264 parameters structure ? (x264_param_t)

  4) I have been told that the x264 static library doesn’t support bitmap input to the encoder and that I have to use libswscale for conversion of the 24bit RGB input bitmap to YUV2. The encoder, supposedly, only takes YUV2 as input ? Is this true ? If so, how do I build libswscale for the x264 static library ?

• FFmpeg convert single image into video Android

  15 mai 2014, par berserk

  I am trying to convert a single image into a video using FFmpeg. I have tried following the files :

  "ffmpeg  -analyzeduration 2147483647 -probesize 2147483647 -i " + packat.get(i).path +"-r 25 -t 1000 -y op.mp4"
  
  
  
  "ffmpeg -loop 1 -r 23.976 -i input.jpg -t 00:00:02 -vcodec qtrle -an output.mov"
  
  
  
  "ffmpeg -i c:\rawvideo\mask.bmp -loop 1 -r 29.97 -s 720x480
  
          -aspect 4:3 -t 00:04:05 -vcodec mjpeg -vb 11261600 -an
  
          c:\rawvideo\fullmask.avi"

  But all of them give me this annoying error :

   Can not process SOS before SOF, skipping marker parser used 0 bytes (0 bits) decode frame unused 0 bytes decoding for stream 0 failed 
  
  Could not find codec parameters for stream 0 (Video: mjpeg): unspecified size
  
  Consider increasing the value for the 'analyzeduration' and 'probesize' options /storage/sdcard0/cblVE/temp/0.jpg: could not find codec parameters 
  
  exit_program: 1 

  Please help. I have searched for a solution from a week, but I have found nothing.

• Command does not complete when executed through a .NET Process ?

  7 mai 2014, par Abe Miessler

  I am using ffmpeg to convert audio files. If I do it through the command line like so :

  ffmpeg -i sourceAudio.wma -f mp3 destAudio.mp3

  it works fine. But when I attempt to do the same thing in a .net application using a Process, ffmpeg starts (and is visible as a running process in my task manager), but never completes. My .NET code never executes past the "WaitForExit" portion unless I go into my task manager and kill the process manually. Code :

  using(Process process = new Process())
  
  {
  
      process.StartInfo.RedirectStandardOutput = true;
  
      //process.StartInfo.RedirectStandardError = true;
  
      process.StartInfo.FileName = Path.GetDirectoryName(System.Diagnostics.Process.GetCurrentProcess().MainModule.FileName) + @"\ffmpeg.exe";
  
      File.Copy(OrigFilePath, LocalFileName, true);
  
      System.Diagnostics.EventLog.WriteEntry("ASP.NET 2.0.50727.0", "Copied file from: " + OrigFilePath + System.Environment.NewLine + "to: " + LocalFileName);
  
      process.StartInfo.Arguments = String.Format(@"-i ""{0}"" -f mp3 ""{1}""", 
  
                                      LocalFileName, 
  
                                      tempDirectory + NewFileName);
  
  
  
  
  
      process.StartInfo.UseShellExecute = false;
  
      process.StartInfo.CreateNoWindow = false;
  
      process.Start();
  
      System.Diagnostics.EventLog.WriteEntry("ASP.NET 2.0.50727.0", "After start...");
  
      string output =  process.StandardOutput.ReadToEnd() + System.Environment.NewLine + process.StandardError.ReadToEnd();
  
      process.WaitForExit();  //<------------------------------ stalls here
  
      System.Diagnostics.EventLog.WriteEntry("ASP.NET 2.0.50727.0", "Conversion completed!  Copying file from: " + LocalConvertedFile + System.Environment.NewLine + OrigFileFolder + "\\" + NewFileName);
  
  
  
      File.Copy(LocalConvertedFile, OrigFileFolder + "\\" + NewFileName,true);
  
      File.Delete(LocalFileName);
  
      File.Delete(LocalConvertedFile);
  
      sw.Stop();
  
      System.Diagnostics.EventLog.WriteEntry("ASP.NET 2.0.50727.0", "Conversion complete. Elapsed time in seconds: " + sw.ElapsedMilliseconds/1000);
  
      return true;
  
  }

  Does anyone know why the process isn’t exiting like it does in the command line ?