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• Streaming and video simutaneosly using ffmpeg

  11 octobre 2013, par user2871193

  I have successfully stored streaming videos from my IP Camera using ffmpeg on my hard drive. I want to stream audio and video simultaneously with it. I wanted to know the commands for it so that the stored video contains audio and video without any lag. Thanks

• use java-ffmpeg wrapper, or simply use java runtime to execute ffmpeg ?

  12 mars 2017, par user156153

  I’m pretty new to Java, need to write a program that listen to video conversion instructions and convert the video once an new instruction arrives (instructions is stored in Amazon SQS, but it’s irrelevant to my question)

  I’m facing a choice, either use Java RunTime to exec ’ffmpeg’ conversion (like from command line), or I can use a ffmpeg wrapper written inJava http://fmj-sf.net/ffmpeg-java/getting_started.php

  I’d much prefer using Java Runtime to exec ffmpeg directly, and avoid using java-ffmpeg wrapper as I have to learn the library. so my question is are there any benefits using java-ffmpeg wrapper over exec ffmpeg directly using Runtime ? I don’t need ffmpeg to play videos, just convert videos

  Thanks

• Getting a poster frame(thumbnail) with ffmpeg

  3 juillet 2012, par Tyler

  I am trying to get a poster frame from a video file, using ffmpeg.

  I have been following this tutorial and come up with the following code(which is taken/adapted from the link I gave) :

  public bool GetVideoThumbnail(string path, string saveThumbnailTo, int seconds)
  
          {
  
              string parameters = string.Format("-i {0} {1} -vcodec mjpeg -ss {2} -vframes 1 -an -f rawvideo", path, saveThumbnailTo, seconds);
  
  
  
              if (File.Exists(saveThumbnailTo))
  
              {
  
                  return true;
  
              }
  
              else
  
              {
  
                  using (Process process = Process.Start(pathToConvertor, parameters))
  
                  {
  
                      process.WaitForExit();
  
                  }
  
                  return File.Exists(saveThumbnailTo);
  
              }
  
          }

  At the moment this code is successfully creating a file in the correct destination (saveThumbnailTo) only the picture is completely black. I have tried changing the seconds value in the code to ensure that I am not just getting a blank picture from the start of the video. The path refers to where my video is stored, by the way.

  I am currently calling the above code like so :

  GetVideoThumbnail(videoPath, folderPath + "/poster.jpg", 100)

  ..and then passing it out to my view to display the picture. I just wonder whether ".jpg" is the extension I should be giving to this file as I am not entirely sure ?

  Edit : When I run the same command from the command line I get the following errors :

  Incompatible pixel format 'yuv420p' for codec 'mjpeg', auto-selecting
  format 'yuvj420p'

  which appears in yellow, and

  [image2 @ 02S96AE0] Could not get frame filename number 2 from pattern
  'poster.jpg' an_interleaved_write_frame() : Invalid argument

  which appears in red.

  Could anyone help me with getting this working properly as I am completely unfamiliar with the ffmpeg command line and not sure what I am doing wrong. I have tried removing the vcodec parameter and get the same error message.