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• Discord music Bot Python starts ffmpeg, green light appears around bot but no audio plays [closed]

  27 avril 2023, par QuestionHaver99

  I've tried using FFmpegOpusAudio and FFMPEGPCMaudio instead, but it gives the same issue. FFMPEG starts and the green light of the bot in the channel shows, but no audio plays, and then the bot exits the channel when the song should be over and FFMPEG terminates. I've tried streaming the audio and playing from a local file, and the same issue.

  


  and just as a quick checklist of confirmed not the issues : the volume is fine and the permissions are fine and ffmpeg is in environment variables and set up correctly.

  


  any advice would be greatly appreciated

  


• How to find mp4 metadata with ffmpeg-light in haskell ?

  21 décembre 2015, par Noughtmare

  I’m using ffmpeg-light, JuicyPixels and gloss to display a video with Haskell. I want to find the metadata of videos I’m playing automatically, but I have not yet found a way to do so.

  I would like to access metadata like the resolution and the framerate of the video.

  Can you help me ?

  EDIT :

  I have tried your solution @CRDrost, but the video is now playing at 2x normal speed. I assume the function imageReaderTime is giving the wrong timestamps.

  EDIT 2 :

  The abnormal playing speed is a bug in the ffmpeg-light library. I’ve opened an issue at the github repository.

  My updated code :

  import Graphics.Gloss
  
  import Codec.FFmpeg
  
  import Codec.FFmpeg.Juicy
  
  import Codec.Picture
  
  import Control.Applicative
  
  import Data.Maybe
  
  import Graphics.Gloss.Juicy
  
  import Control.Monad
  
  -- import System.IO.Unsafe (unsafePerformIO)-- for debugging purposes
  
  
  
  resolution :: (Int,Int)
  
  resolution = (640, 360)
  
  
  
  frameCount :: Int
  
  frameCount = 100
  
  
  
  main :: IO ()
  
  main = do
  
      initFFmpeg
  
      (getFrame, cleanup) <- imageReaderTime "big_buck_bunny.mp4"
  
      frames <- replicateM frameCount $ nextFrame getFrame
  
      cleanup
  
      animate (InWindow "Nice Window" resolution (10,10)) white (frameAt frames)
  
  
  
  nextFrame :: IO (Maybe (Image PixelRGB8, Double)) -> IO (Picture, Float)
  
  nextFrame getFrame = mapSnd realToFrac . mapFst fromImageRGB8 . fromJust <$> getFrame
  
  
  
  frameAt :: [(Picture, Float)] -> Float -> Picture
  
  frameAt list time = fst . head . dropWhile ((< time) . snd) $ list
  
  
  
  mapFst :: (a -> c) -> (a, b) -> (c, b)
  
  mapFst f (a, b) = (f a, b) -- applies f to first element of a 2-tuple
  
  
  
  mapSnd :: (b -> c) -> (a, b) -> (a, c)
  
  mapSnd f (a, b) = (a, f b) -- applies f to the second element of a 2-tuple

• Animated WebP vs MP4. Why is MP4 so light and which is generally better ?

  25 juin 2022, par Red Vic

  I ran some tests and all things being equal, mp4 is much lighter than animated WebP's.

  


  I used FFmpeg and here are the results :

  


  

  • Encode to an animated WebP at 25fps with quality at 90% => 2.42 MB

  


  • Encode to an mp4 at 25fps with quality at 90% => 392 KB.

  


  


  This left me wondering why the heck did I choose WebP as the main format for my web platform. Any idea whether I should ditch the animated WebP's and use mp4 instead with loop HTML tag and no audio ?