Newest 'ffmpeg' Questions - Stack Overflow

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• How to do make a loading screen for ffmpeg using c# asp.net

  1er septembre 2011, par anthonypliu

  I have this function and where the Debug.WriteLine commands are is where I output the values. How would I get this data to print into a webpage so I can mimic a loading screen? I am calling this function externally through a *.ashx web service file.

  private string ConvertToFLV(string phyicalFilePath)
          {
              if (Path.GetExtension(phyicalFilePath).Equals(".flv")) return phyicalFilePath;
  
              var argument = string.Format(@"-i ""{0}"" -vcodec flv -f flv -r 29.97 -s 320x240 -aspect 4:3 -b 300k -g 160 -cmp dct  -subcmp dct  -mbd 2 -flags +aic+cbp+mv0+mv4 -trellis 1 -ac 1 -ar 22050 -ab 56k ""{1}""", phyicalFilePath, Path.ChangeExtension(phyicalFilePath, "flv"));
              libfaac -ar 48000 -ab 128k -coder 1 -flags +loop -cmp +chroma -partitions +parti4x4+partp8x8+partb8x8 -me_method hex -subq 6 -me_range 16 -g 250 -keyint_min 25 -sc_threshold 40 -i_qfactor 0.71 -b_strategy 1 -threads 0 {1}", phyicalFilePath, Path.ChangeExtension(phyicalFilePath, "mp4"));
              File.Delete(Path.ChangeExtension(phyicalFilePath, "flv"));
  
              ProcessStartInfo process = new ProcessStartInfo(ffmpegPhysicalPath, argument);
              Process proc = new Process();
              float duration = 0.00F, current = 0.00F;
              proc.StartInfo = process;
              proc.EnableRaisingEvents = false;
              proc.StartInfo.UseShellExecute = false;
              proc.StartInfo.CreateNoWindow = true;
              proc.StartInfo.RedirectStandardOutput = true;
              proc.StartInfo.RedirectStandardError = true;
  
              proc.Start();
  
              StreamReader d = proc.StandardError;
  
              do
              {
                  string s = d.ReadLine();
                  if (s.Contains("Duration: "))
                  {
                      Debug.WriteLine("DURATION: " + s);
  
                  }
                  else
                  {
                      if (s.Contains("frame="))
                      {
                          Debug.WriteLine("FRAME: " + s);
  
                      }
                  }
              } while (!d.EndOfStream);
  
  
              proc.WaitForExit();
  
              return Path.ChangeExtension(phyicalFilePath, "flv");
  

• how can I play ffmpeg codecs not supported by MedicaPlayer ? [closed]

  1er septembre 2011, par Jun

  Currently, I'm using MediaPlayer to play mp4, 3gp videos and it works as it should do but now I need to play ffmpeg codecs too.

  In this case, do I have to develop my video player or is there any players from 3rd parties?

  Thanks in advance.

• Convert RTP/UDP Stream to HTTP with ffmpeg

  31 août 2011, par inversus

  As you may know, Android uses a strange implementation of RTP - It can only play low bitrate RTP streams. On the other hand, it can play Full HD HTTP stream flawlessly.

  I'm trying a workaround for this problem: As stated in the title, using ffmpeg to convert the RTP/UDP stream to HTTP.

  I've already compile ffmpeg for android, but I'm having difficulties configuring the ffserver.conf.

  1. Is it possible to achieve what I want with ffmpeg?
  2. I dont need any transcoding, will it use lots of the processor/memory?
  3. Can you help me with these configurations?

  I receive a udp/rtp multicast stream:

  • udp://@239.192.1.31:1234 or rtp://@239.192.1.31:1234 - TV channels

  I want to output to HTTP:

  • http://127.0.0.1:8090/stream.mp4

  Thank you in advance
  inversus

• A .NET P/Invoke to convert with ffmpeg ?

  31 août 2011, par Shimmy

  I need to create a program that should convert audio and video files to supported types.

  I've found ffmpeg to be a great tool. However I donno C (which ffmpeg was written with), and I was wondering if there is a way (besides command-line which I donnu if I would use since I'm not sure if you can control the conversion process and get info about its percentage) that I can interact with ffmpeg and build a conversion program on it's API.

  Basically I'm looking for a single .NET-compatible method:

  void Convert(sourceFile, targetFile, string targetExtension);
  

  It shouldn't ask for bitrate etc., but only should it try to make a 1 to 1 conversion.

  I don't know how to write the underlying P/Invoke, and since I donno ffmpeg from inside, I can't tell what dll it uses, so even I'd want to write the PI myself, I don't know what among the zillion functions of the ffmpeg libraries the conversion functions are.

  So any guidance or approach will be really appreciated.

• Trouble with the ffmpeg -ss flag when capturing one frame from a Macbook iSight webcam

  31 août 2011, par Andy

  For about five years I've used ffmpeg in a shell script to grab one frame from my linux'd-up Macbook's iSight:

  ffmpeg -f video4linux2 -s 640x480 -r 15 -i /dev/video0 -an -vframes 1 -vcodec mjpeg -y -sameq -ss 1.5 snapshot.jpg
  

  I just upgraded my Ubuntu distro from Lucid to Natty (ffmpeg ver. 0.6.2-4:0.6.2-1ubuntu1). Now that syntax turns the iSight on but hangs indefinitely.

  [output snipped, ending with:]
  frame=    0 fps=  0 q=0.0 Lsize=      -0kB time=10000000000.00 bitrate=  -0.0kbits/s    
  video:0kB audio:0kB global headers:0kB muxing overhead -inf%
  

  Without the '-ss' flag it seems to successfully grab the first frame and exit immediately - the only difference in output being:

  frame=    1 fps=  0 q=0.0 Lsize=      -0kB time=0.07 bitrate=  -2.6kbits/s    
  video:16kB audio:0kB global headers:0kB muxing overhead -100.132730%
  

  However, the '-ss 1.5' was necessary to delay the frame capture by 1.5 seconds to allow the cam sufficient time to adjust the exposure.

  The -itsoffset flag seemed promising, but doesn't seem to change ffmpeg's behavior (ie doesn't hang, but no delay).

  Any ideas?