Recherche avancée

Sur d’autres sites (3316)

• Python PyQt5 and youtube-dl GUI console popping when converting to mp3 with ffmpeg [on hold]

  29 juin 2018, par Giblin

  I will be jumping right to the issue I am having for a while.
  I have built a GUI software with Python 3.6 with PyQt5 and the youtube-dl package for downloading audios.
  The software downloads files in mp4, 3gp, m4a and webm extensions with no problems at all and then, here comes the mp3 to change the balance for ever !
  So what it basically does, is that while it downloads it as mp3, by the time it converts it with ffmpeg (same issue with ffprobe), a console window pops right out of the GUI and does its magic.
  I have made all the necessary customizations in the code, such as to run the ffmpeg with verbose etc but it won’t go away.
  Changing the file extension from .py to .pyw doesn’t help either.
  I think it is more of a windows problem and not really a programming issue, so I thought maybe a bat script could always run it silent in the background when it pops ? And if so, I would appreciate a heads-up because I have no experience in bat scripting.
  Thanks in advance and sorry if I went on for too long.

  EDIT :

  Here’s the console I get during the convert when I download a URL as mp3 (this pops like that until it finishes the conversion to mp3 and then disappears) :

  FFMPEG Console

  And here’s the function with the options responsible for that (for other extensions, the code is similar with just few name changes but ffmpeg isn’t necessary for them in order to convert) :

  def youtubeMP3(self):
  
      options = {
  
          'format': 'bestaudio/best',
  
          'extractaudio': True,
  
          'audioformat': 'mp3',
  
          'outtmpl': self.location + '/%(title)s-%(id)s.%(ext)s',
  
          'quiet': True,
  
          'no_warnings': True,
  
          'nocheckcertificate': True,
  
          'progress_hooks': [self.hookMP3],
  
          'postprocessors': [{
  
              'key': 'FFmpegExtractAudio',
  
              'preferredcodec': 'mp3',
  
              'preferredquality': '192'
  
          }]
  
      }
  
      value = self.urlText.text()
  
      if value != "" and validators.url(value):
  
          with youtube_dl.YoutubeDL(options) as ydl:
  
              try:
  
                  ydl.download([value])
  
                  self.progressLabel.setText("The download was successful.")
  
                  self.urlText.clear()
  
                  time.sleep(5)
  
                  self.progressLabel.setText("")
  
              except:
  
                  self.progressLabel.setText("This video URL does not exist.")
  
                  self.urlText.clear()
  
                  time.sleep(5)
  
                  self.progressLabel.setText("")

• FFMPEG extracting frames is slow even with CUDA

  5 juin 2023, par Ξένη Γήινος

  I have a bunch of videos at some location that I want to extract frames from.

  


  The videos are of .wmv format, and have a framerate of 25, and I want to extract all frames from them losslessly.

  


  And I do have a dedicated graphics card (NVIDIA Geforce GTX 1050 Ti, I know it's old), so I want to utilize it to accelerate frame extraction. I downloaded FFMPEG with CUDA support from www.gyan.dev for exactly this.

  


  I came up with this PowerShell command :

  


  gci C:\Users\Xeni\Documents -filter *.wmv | %{
 $folder = 'C:\Users\Xeni\Desktop\' + $($_.name -replace '.wmv')
 md $folder;
 D:\ffmpeg\ffmpeg.exe -hwaccel cuda -i $_.fullname -vf fps=25 "$folder\%05d.bmp"
}


  


  But somehow it is slow, its disk write speed is less than 100 MiB/s and it uses less than 1% GPU, and it takes about 2 seconds to process 25 frames.

  


  How can I speed up this command ?

  


• Projecting camera feed with a delay

  28 septembre 2022, par Viktor Vošček

  I'm working on a project which involves capturing output from a camera via HDMI (Sony Alpha A7 IV), and projecting it via a laser/lamp projector, but the catch is that the stream which is going into the projector should be delayed by 4 minutes. (If you start recording something at 10:00am, it will start playing back at 10:04am, etc.) It should be capturing and playing back the feed non-stop for the whole day.

  


  First I was thinking of using FFplay to display a DirectShow stream from a HDMI capture card (like the Elgato 4K60 Pro) and opening the FFplay window on the 'projector screen', but I wasn't able to find any way to manually add delay to the stream. My second idea was to record the actual feed to a video file, and then immediately play it back in intervals (still using FFmpeg+FFplay).

  


  Any other ideas/thoughts ?