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• Build : Bump and merge JSHint/JSCS config

  27 mai 2014, par nschonni

  Build : Bump and merge JSHint/JSCS config
  Moved options depreciated in the latest JSHint to the JSCS version.
  

• Issues with ffmpeg2theora- Please port your application to avcodec_decode_audio4()

  8 août 2016, par sudheerpaturi

  I am using the latest versions of ffmpeg and ffmpeg2theora for windows. I try to convert an mp4 file(with audio) to an ogv file using this command on terminal

  ffmpeg2theora.exe -v 10 input_file_name.mp4

  Then its giving out this error.
  Image for the Output

  I am totally new to using this tool. From my investigation I found that this is because of the new versions. This problem doesn’t exist with the old versions.

  Is there any way to get rid of this issue ?

  Thanks in advance.

• FFmpeg with Pipe - how can I periodically grab real-time frames out of live streams in C# ?

  2 mars 2020, par BBy

  I am new to FFmpeg and C# and I want grab frames to do image processing with IP Camera.

  I have made the following C# class and I could get a single frame from IP Camera.

  class FFmpegHandler
  
      {
  
          public Process ffmpeg = new Process();
  
          public Image image;
  
  
  
          public Image init()
  
          {
  
              ffmpeg = new Process()
  
              {
  
                  StartInfo =
  
                  {
  
                      FileName = @"./ffmpeg/ffmpeg.exe",
  
                      //Arguments = "-i http://admin:@192.168.10.1/videostream.asf -an -f image2pipe -preset ultrafast -tune zerolatency -s 320x240 pipe:1", // Hangs
  
                      Arguments = "-i http://admin:@192.168.10.1/videostream.asf -vframes 1 -an -f image2pipe -preset ultrafast -tune zerolatency -s 320x240 pipe:1",
  
                      UseShellExecute = false,
  
                      RedirectStandardOutput = true,
  
                      RedirectStandardError = true,
  
                      CreateNoWindow = true,
  
                      WorkingDirectory = "./ffmpeg/"
  
                  }
  
              };
  
  
  
              ffmpeg.EnableRaisingEvents = true;
  
              ffmpeg.Start();
  
  
  
              var stream = ffmpeg.StandardOutput.BaseStream;
  
              var img = Image.FromStream(stream);
  
              //ffmpeg.WaitForExit();
  
  
  
              return img;
  
          }
  
      }   

  The problem is that I want to grab real-time (latest) images when I request.

  If I run FFmpegHandler.init(), it will take 2 seconds to give me delayed image output.

  I have tried removing argument -vframes 1, then it will hang after image = Image.FromStream(stream) ;.

  When I check the ffmpeg output directly, it looks like ffmpeg is keep building the stream

  frame=    6 fps=0.0 q=2.2 size=      25kB time=00:00:00.24 bitrate= 861.9kbits/s dup=4 drop=0 speed=0.435x    
  
  frame=   65 fps= 60 q=24.8 size=     140kB time=00:00:02.60 bitrate= 440.9kbits/s dup=4 drop=0 speed=2.41x    
  
  frame=   77 fps= 49 q=24.8 size=     161kB time=00:00:03.08 bitrate= 428.0kbits/s dup=4 drop=0 speed=1.95x    
  
  frame=   89 fps= 43 q=24.8 size=     182kB time=00:00:03.56 bitrate= 418.6kbits/s dup=4 drop=0 speed= 1.7x    
  
  frame=  102 fps= 39 q=24.8 size=     205kB time=00:00:04.08 bitrate= 410.7kbits/s dup=4 drop=0 speed=1.57x    
  
  frame=  116 fps= 37 q=24.8 size=     229kB time=00:00:04.64 bitrate= 404.2kbits/s dup=4 drop=0 speed=1.49x    
  
  frame=  128 fps= 35 q=24.8 size=     250kB time=00:00:05.12 bitrate= 399.8kbits/s dup=4 drop=0 speed=1.41x    
  
  frame=  142 fps= 34 q=24.8 size=     274kB time=00:00:05.68 bitrate= 395.7kbits/s dup=4 drop=0 speed=1.36x    
  
  frame=  156 fps= 33 q=24.8 size=     299kB time=00:00:06.24 bitrate= 392.3kbits/s dup=4 drop=0 speed=1.32x    
  
  frame=  169 fps= 32 q=24.8 size=     322kB time=00:00:06.76 bitrate= 389.7kbits/s dup=4 drop=0 speed=1.29x    
  
  frame=  182 fps= 32 q=24.8 size=     344kB time=00:00:07.28 bitrate= 387.4kbits/s dup=4 drop=0 speed=1.26x    
  
  frame=  195 fps= 31 q=24.8 size=     367kB time=00:00:07.80 bitrate= 385.5kbits/s dup=4 drop=0 speed=1.24x    
  
  frame=  208 fps= 31 q=24.8 size=     390kB time=00:00:08.32 bitrate= 383.8kbits/s dup=4 drop=0 speed=1.22x    
  
  frame=  221 fps= 30 q=24.8 size=     413kB time=00:00:08.84 bitrate= 382.3kbits/s dup=4 drop=0 speed=1.21x   

  How can I grab the latest frames out of this live-stream image ? (OR is there a thread-safe way to clean the stream and only get the latest frame when I request ?)