Recherche avancée

Sur d’autres sites (5711)

• Convert wma stream to mp3 stream with C# and ffmpeg

  24 septembre 2012, par user1363468

  Is it possible to convert a wma stream to an mp3 stream real time ?

  I have tried doing something like this but not having any luck :

      WebRequest request = WebRequest.Create(wmaUrl);
  
      HttpWebResponse response = (HttpWebResponse)request.GetResponse();
  
      int block = 32768;
  
      byte[] buffer = new byte[block];
  
  
  
      Process p = new Process();
  
      p.StartInfo.UseShellExecute = false;
  
      p.StartInfo.ErrorDialog = false;
  
      p.StartInfo.RedirectStandardInput = true;
  
      p.StartInfo.RedirectStandardOutput = true;
  
      p.StartInfo.RedirectStandardError = true;
  
      p.StartInfo.FileName = "c:\\ffmpeg.exe";
  
      p.StartInfo.Arguments = "-i - -y -vn -acodec libspeex -ac 1 -ar 16000 -f mp3 ";
  
  
  
      StringBuilder output = new StringBuilder();
  
  
  
      p.OutputDataReceived += (sender, e) =>
  
      {
  
        if (e.Data != null)
  
        {
  
          output.AppendLine(e.Data);
  
          //eventually replace this with response.write code for a web request
  
        }
  
      };
  
  
  
      p.Start();
  
      StreamWriter ffmpegInput = p.StandardInput;
  
  
  
      p.BeginOutputReadLine();
  
  
  
      using (Stream dataStream = response.GetResponseStream())
  
      {
  
         int read = dataStream.Read(buffer, 0, block);
  
  
  
         while (read > 0)
  
         {
  
            ffmpegInput.Write(buffer);
  
            ffmpegInput.Flush();
  
            read = dataStream.Read(buffer, 0, block);
  
         }
  
      }
  
  
  
      ffmpegInput.Close();
  
  
  
      var getErrors = p.StandardError.ReadToEnd();

  Just wondering if what I am trying to do is even possible (Convert byte blocks of wma to byte blocks of mp3). Open to any other possible C# solutions if they exist.

  Thanks

• Celery to process task and modify the model fields

  15 juillet 2015, par Robin

  I would like to convert video into mp4 using ffmpeg and celery for the asynchronous task. When user uploads a video, it will be for the original_video and save it. After that I want celery to convert it into a different version for the mp4_720 field. However I am confused on how to apply that logic using celery.

  app.models.py :

  class Video(models.Model):
  
      title = models.CharField(max_length=75)
  
      pubdate = models.DateTimeField(default=timezone.now)
  
      original_video = models.FileField(upload_to=get_upload_file_name)
  
      mp4_720 = models.FileField(upload_to=get_upload_file_name, blank=True, null=True)
  
      converted = models.BooleanField(default=False)

  app.views.py :

  def upload_video(request):
  
      if request.POST:
  
          form = VideoForm(request.POST, request.FILES)
  
          if form.is_valid():
  
              video = form.save(commit=False)
  
              video.save()
  
  
  
              // Celery to convert the video
  
              convert_video.delay(video)
  
  
  
              return HttpResponseRedirect('/')
  
      else:
  
          form = VideoForm()
  
      return render(request, 'upload_video.html', {
  
          'form':form
  
      })

  app.tasks.py :

  @app.task
  
  def convert_video(video):
  
  
  
      // Convert the original video into required format and save it in the mp4_720 field using the following command:
  
      //subprocess.call('ffmpeg -i (path of the original_video) (video for mp4_720)')
  
  
  
      // Change the converted boolean field to True
  
  
  
      // Save

  Basically my question is how to save the converted video in mp4_720. Your help and guidance will be very much appreciated. Thank you.

  ** update **

  What I want that method to do is first convert the video.original_video and then save the converted video in the video.mp4_720 field. If all has been done correctly, change the video.converted to True. How do I define the method to do so ?

• How to use stdout.write in python3 when piping to ffmpeg ?

  10 décembre 2020, par user14644144

  My main goal for this project I'm working on is to use a python script to get any webcam footage, edit it with opencv, and then pipe the edited video frames with ffmpeg to a dummy webcam from v4l2loopback. Here's the sample code I made that runs exactly as I want to on python 2.7 :

  


  


  


  import cv2
import subprocess as sp
import sys

cap = cv2.VideoCapture(1)

cv2.namedWindow('result', cv2.WINDOW_AUTOSIZE)

while True:
    ret, frame = cap.read()
    cv2.imshow('result', frame)

    sys.stdout.write(frame.tostring())

    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()

  


  


  



  and then run it with

  


  


  


  python pySample.py | ffmpeg -f rawvideo -pixel_format bgr24 -video_size 640x480 -framerate 30 -i - -vf format=yuv420p -f v4l2 /dev/video17

  


  


  



  However, I want it to work with python3 instead of 2.7, and I found a way to make it work where I replace the "sys.stdout..." line with

  


  


  


  sys.stdout.buffer.write(frame.tobytes())

  


  


  



  This works well, except that it only runs at 14 fps while the 2.7 code could run at 30. I'm kind of at a loss as to how to fix this issue/ what this issue exactly is. I'm running this on a raspberry pi if that helps. Thanks so much !