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• Revision 5ebe94f9f1 : Build fixes to merge vp9-preview into master Various fixups to resolve issues w

  23 décembre 2012, par John Koleszar

  Changed Paths : Add /examples/decode_with_partial_drops.txt Modify /libs.mk Modify /test/test.mk Modify /test/test_libvpx.cc Modify /vp9/common/generic/vp9_systemdependent.c Modify /vp9/common/vp9_alloccommon.c Modify /vp9/common/vp9_blockd.h (...)

• Memory issues when using ffmpeg and gloss to play videos

  21 décembre 2015, par Noughtmare

  I’m trying to make a video player with haskell using ffmpeg-light, JuicyPixels and gloss. I’m now able to play video, but frames that have been played stay in memory. This causes major memory issues. How can I avoid storing all the frames in memory ?

  Here is my code :

  {-# LANGUAGE FlexibleContexts #-}
  
  module Main where
  
  
  
  -- For my own 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 (when, join)
  
  import Codec.FFmpeg.Decode
  
  import Codec.FFmpeg.Enums
  
  import Control.Monad.Error.Class
  
  import Control.Arrow (first)
  
  import Control.Monad.Except (runExceptT)
  
  import Graphics.Gloss.Interface.IO.Animate
  
  import Data.IORef
  
  
  
  -- Temporary hardcoded resolution
  
  resolution :: (Int,Int)
  
  resolution = (640, 360)
  
  
  
  main :: IO ()
  
  main = do
  
      -- First initialize ffmpeg, this needs to be run before other ffmpeg functions
  
      initFFmpeg
  
      -- Open the samplevideo for reading. video :: IO (IO (Maybe (AVFrame, Double)), IO ())
  
      video <- runExceptT $ frameReaderTime' avPixFmtRgb24 "SampleVideo_640x360_1mb.flv"
  
      either
  
            -- This code gets called when the frameReader reports an error
  
            (const $ putStrLn "Can't read file")
  
            -- This opens a new window and plays the video in it on a white background
  
            (animateFixedIO (InWindow "Nice Window" resolution (10, 10)) white . frameAtWait . fst)
  
  
  
            video
  
  
  
  -- This finds the frame at given time
  
  frameAtWait :: IO (Maybe (AVFrame, Double)) -> Float -> IO Picture
  
  frameAtWait getFrame time = do
  
      -- This gets the next frame from the video
  
      (frame, t) <- fromJust <$> getFrame
  
      -- t has to be converted from Double to Float
  
      let t' = realToFrac t
  
          -- The difference between the requested time and the actual frame time
  
          difference = t' - time
  
      -- If the frame is not yet supposed to be shown
  
      if difference > 0 then do
  
          -- Wait until it is
  
          threadDelay . round . (* 1000000) $ difference
  
          -- then return it
  
          fromJust <$> frameToPicture frame
  
      else
  
          -- return it immediately
  
          fromJust <$> frameToPicture frame
  
  
  
  -- This function converts a ffmpeg internal AVFrame to a gloss picture
  
  frameToPicture :: AVFrame -> IO (Maybe Picture)
  
  frameToPicture frame = do
  
      -- convert it to a juicypixels dynamicimage
  
      dynImage <- toJuicy frame
  
      -- then convert it to a gloss picture and return it
  
      return . join $ fmap fromDynamicImage dynImage

• Python and ffmpeg audio sync and screen recording issues

  9 août 2020, par odddollar

  I'm using ffmpeg and python to record my desktop screen. When the program is run, it starts recording, then when I press a key-combo it cuts off the last x amount of seconds and saves it then starts recording again ; similar to the "record that" functionality of windows game bar.

  


  I have it working so it records video just fine, but then I change the ffmpeg command to record audio from my desktop and I get an error saying ValueError: could not convert string to float: 'N/A' occurring when I try to calculate the length of the recorded video. It appears as though the recording isn't being stopped until after I try to calculate the video length, even though this exact same code works fine when not recording audio.

  


  Additionally, I also have an issue when recording audio in that the audio is a couple hundred milliseconds in front of the video. It's not a lot but it's enough to be noticeable.

  


  What I'm overall asking, is there a way I can modify the ffmpeg command to prevent the audio desync issues, and what might be causing the problems I'm getting when attempting to find the length of the video with audio ?

  


  import keyboard, signal
from os import remove
from os.path import isfile
from subprocess import Popen, getoutput
from datetime import datetime
import configparser

class Main:
    def __init__(self, save_location, framerate, duration):
        self.save_location = save_location
        self.framerate = int(framerate)
        self.duration = int(duration)
        self.working = self.save_location + '\\' + 'working.avi'
        self.start_recording()

    def start_recording(self):
        if isfile(self.working):
            remove(self.working)

        # start recording to working file at set framerate
        self.process = Popen(f'ffmpeg -thread_queue_size 578 -f gdigrab -video_size 1920x1080 -i desktop -f dshow -i audio="Stereo Mix (Realtek High Definition Audio)" -b:v 7M -minrate 4M -framerate {self.framerate} {self.working}')
        #self.process = Popen(f'ffmpeg -f gdigrab -framerate {self.framerate} -video_size 1920x1080 -i desktop -b:v 7M -minrate 2M {self.working}')

    def trim_video(self):
        # stop recording working file
        self.process.send_signal(signal.CTRL_C_EVENT)

        # call 'cause I have to
        getoutput(f"ffprobe -i {self.working}")

        # get length of working video
        length = getoutput(f'ffprobe -i {self.working} -show_entries format=duration -v quiet -of csv="p=0"')

        # get time before desired recording time
        start = float(length) - self.duration

        # get save location and title
        title = self.save_location+'\\'+self.get_time()+'.avi'

        # cut to last amount of desired time
        Popen(f"ffmpeg -ss {start} -i {self.working} -c copy -t {self.duration} {title}")
        getoutput(f"ffprobe -i {self.working}")

        self.start_recording()

    def get_time(self):
        now = datetime.now()
        return now.strftime("%Y_%m_%d#%H-%M-%S")


if __name__ == "__main__":
    config = configparser.ConfigParser()
    config.read("settings.ini")
    config = config["DEFAULT"]

    run = Main(config["savelocation"].replace("\\", "\\\\"), config["framerate"], config["recordlast"])
    keyboard.add_hotkey("ctrl+shift+alt+g", lambda:run.trim_video())

    while True:
        try:
            keyboard.wait()
        except KeyboardInterrupt:
            pass


  


  The contents of the settings.ini file are listed below

  


  [DEFAULT]
savelocation = C:\
framerate = 30
recordlast = 10


  


  In the code block, the first line with self.process = Popen is the one that records audio and has the issues, the second line (the commented out one below) is the one that works fine.