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• libav : Filling AVFrame with RGB24 sample data ?

  31 mai 2012, par Ashika Umanga Umagiliya

  I am trying to fill sample data for a AVFrame initialized with RGB24 format.
  I use following code snippet to populate RGB data.
  But in the encoded video,I can only see grayscale strip covering only 1/3 of the videoframe.
  This code snippet suppose to fill only Red color.
  Any tips what Im doing wrong here ?

  AVFrame *targetFrame=.....
  
  int height=imageHeight();
  
  int width=imageWidth();
  
  
  
  
  
    for(y=0;ydata[0][(y* width)+x]=(x%255); //R  
  
     targetFrame->data[0][(y* width)+x+1]=0;     //G
  
     targetFrame->data[0][(y* width)+x+2]=0;     //B
  
  
  
  
  
    }
  
     }

• Is there a way to use youtube-dl in async

  8 octobre 2024, par Stam Kaly

  I have an application where I use zmq with asyncio to communicate with the clients who have the ability to download a video with youtube-dl to the server. I tried adding await to youtube_dl's download function but it gave me an error since it was not a coroutine. My code right now is simply looking like this :

  



  import asyncio
import youtube_dl


async def networking_stuff():
    download = True
    while True:
        if download:
            print("Received a request for download")
            await youtube_to_mp3("https://www.youtube.com/watch?v=u9WgtlgGAgs")
            download = False
        print("Working..")
        await asyncio.sleep(2)


async def youtube_to_mp3(url):
    ydl_opts = {
        'format': 'bestaudio/best',
        'postprocessors': [{
            'key': 'FFmpegExtractAudio',
            'preferredcodec': 'mp3',
            'preferredquality': '192',
        }]
    }

    with youtube_dl.YoutubeDL(ydl_opts) as ydl:
        ydl.download([url])


loop = asyncio.get_event_loop()
loop.create_task(networking_stuff())
loop.run_forever()


  



  which gives the following output :

  



  Received a request for download
[youtube] u9WgtlgGAgs: Downloading webpage
[youtube] u9WgtlgGAgs: Downloading video info webpage
[youtube] u9WgtlgGAgs: Extracting video information
[youtube] u9WgtlgGAgs: Downloading MPD manifest
[download] Destination: The Cardigans - My Favourite Game “Stone Version”-u9WgtlgGAgs.webm
[download] 100% of 4.20MiB in 00:03
[ffmpeg] Destination: The Cardigans - My Favourite Game “Stone Version”-u9WgtlgGAgs.mp3
Deleting original file The Cardigans - My Favourite Game “Stone Version”-u9WgtlgGAgs.webm (pass -k to keep)
Working..
Working..
....
Working..
Working..


  



  whereas I would expect the Working.. message to be printed in between youtube-dl's messages as well. Am I missing something here or is this impossible with async/await ? Is ffmpeg blocking ? If so, can I run the download in async without converting to mp3 or is using threads the only way ?

  


• speed up Watermarking process in FFmpeg

  24 octobre 2017, par 1234567

  speed up Watermarking process in FFmpeg

  Is there any way to speed up water marking process in Ffmpeg

  I have a video 5 seconds long and want to add watermark over it

  the command used is

  "-y","-i", j, "-i", image1, "-filter_complex",
  
                  "overlay=0:0","-codec:a", "copy","-preset","ultrafast", out

  even after using ultrafast and using same code not re-encode the audio it is very slow, any help would be useful