Recherche avancée

Sur d’autres sites (7787)

• Php- Create a video from a video file [on hold]

  18 novembre 2016, par baig772

  I have a requirement where I upload the video file for the user and then I have to create a trailer for that video and then send that trailer video in an email to user.
  I have looked into ffmpeg that creates video from still images, but is there any way that I could create a short video from a video using PHP ?
  OR
  Is there any way to set the start and end time of the main video in the iframe so that user could see the video for that specific duration ?

• System.IO.IOException : Pipe is broken error with FFMpegCore library

  14 octobre 2024, par secretply

  I am looking to retrieve the loudnorm data in JSON format from FFmpeg (using FFMpegCore 5.1.0). This is the code I currently have :

  


  await FFMpegArguments
    .FromPipeInput(new StreamPipeSource(fileStream.OpenReadStream()))
    .OutputToPipe(new StreamPipeSink(outputStream), options => options.WithCustomArgument("-af loudnorm=print_format=json"))
    .ProcessAsynchronously();


  


  This is the exception I get, which is similar to this old GitHub issue.

  


  System.IO.IOException: 'Pipe is broken.'

This exception was originally thrown at this call stack:
    System.IO.Pipes.PipeStream.PipeValueTaskSource.GetResult(short)
    System.IO.Pipes.PipeStream.PipeValueTaskSource.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(short)
    System.IO.Stream.CopyToAsync.__Core|27_0(System.IO.Stream, System.IO.Stream, int, System.Threading.CancellationToken) in Stream.cs
    FFMpegCore.Arguments.InputPipeArgument.ProcessDataAsync(System.Threading.CancellationToken)
    FFMpegCore.Arguments.PipeArgument.During(System.Threading.CancellationToken)
    FFMpegCore.FFMpegArguments.During(System.Threading.CancellationToken)
    FFMpegCore.FFMpegArgumentProcessor.Process(Instances.ProcessArguments, System.Threading.CancellationTokenSource)
    FFMpegCore.FFMpegArgumentProcessor.ProcessAsynchronously(bool, FFMpegCore.FFOptions)


  


  I am trying to replicate the following FFmpeg command and JSON output :

  


  ffmpeg -i "file.flac" -af loudnorm=print_format=json -f null -


  


  {
        "input_i" : "-21.87",
        "input_tp" : "-7.13",
        "input_lra" : "5.00",
        "input_thresh" : "-32.04",
        "output_i" : "-24.76",
        "output_tp" : "-10.36",
        "output_lra" : "4.10",
        "output_thresh" : "-34.84",
        "normalization_type" : "dynamic",
        "target_offset" : "0.76"
}


  


  If I add .ForceFormat("null") to the OutputToPipe options, I do not get the exception but when I read the output stream, it returns an empty string. In the issue mentioned, I know they mentioned a way to get the FFMpegErrorOutput property but I do not know how that can be done. I could not find an example of outputting a stream as JSON. If anyone can point me in the right direction or can provide an alternative solution, I would greatly appreciate it.

  


• ffmpeg in the use of libardrone by python

  13 mai 2016, par Chao Wang

  Recently I am trying to do a vision-based control using AR.drone 2.0. I meet a problem in the first step that is to import video seen from drone to my PC. I searched online and there is a library called libardrone. I tried to used it but when I do the first step that is to intialize. I wrote

  drone = libardrone.libardrone.ARDrone(True)

  The problem rises in the installation of ffmpeg. I actually installed and set ffmpeg\bin in my path, but I don’t know why it keeps jumping out this error

  The error turns out to be

  Traceback (most recent call last) :

  File "C:\Python27\dronetest.py", line 7, in <module>
  
      drone=libardrone.ARDrone(is_ar_drone_2=True,hd=True)
  
    File "C:\Python27\lib\site-packages\libardrone\libardrone.py", line 126, in __init__
  
      self.network_process = arnetwork.ARDroneNetworkProcess(com_pipe_other, is_ar_drone_2, self)
  
    File "C:\Python27\lib\site-packages\libardrone\arnetwork.py", line 45, in __init__
  
      self.ar2video = ar2video.ARVideo2(self._drone, libardrone.DEBUG)
  
    File "C:\Python27\lib\site-packages\libardrone\ar2video.py", line 37, in __init__
  
      self.h264 = h264decoder.H264Decoder(self, drone.image_shape)
  
    File "C:\Python27\lib\site-packages\libardrone\h264decoder.py", line 82, in __init__
  
      raise Exception("You need to install ffmpeg to be able to run ardrone")
  
  Exception: You need to install ffmpeg to be able to run ardrone
  
  </module>

  The related code in h264decoder.py is

   if (H264Decoder.which('ffmpeg') is None):
  
                      raise Exception("You need to install ffmpeg to be able to run ardrone")
  
  
  
  ....
  
  
  
  
  
  def which(program):
  
          def is_exe(fpath):
  
              return os.path.isfile(fpath) and os.access(fpath, os.X_OK)
  
  
  
          fpath, fname = os.path.split(program)
  
          if fpath:
  
              if is_exe(program):
  
                  return program
  
          else:
  
              for path in os.environ["PATH"].split(os.pathsep):
  
                  path = path.strip('"')
  
                  exe_file = os.path.join(path, program)
  
                  if is_exe(exe_file):
  
                      return exe_file
  
  
  
          return None