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• Covert video to frames, then back to video without altering the frames in python

  7 mars 2021, par Rashiq

  I am writing a script in python that converts a video (let this video be X) into frames (X′) and then back into the same video (Y). Now, when I break video Y back into frames (Y′) the images are not equal to X′ frames i.e. they have different hashes. I would expect them to be the same, and if being not the same is the expected behaviour, how can I make them the same ?

  


  Is there a way to go from

  


  `video, X —> frames, X′, —> video, Y, —> frames, Y′, —> video, Z, —> frames, Z′

  


  and so on without changing the output from its previous state such the videos X, Y, Z and frames X′, Y′, Z′ are same to each other in their respective sets ?

  


  I have tried multiple video codecs (mp4, avi, mkv) and image formats (tif, jpeg, png). To my understanding, lossy compression codecs should not work by lossless such as tif are not producing consistent output either.

  


  I have followed these video-to-frame and frame-to-video among other tutorials but to no avail. Any help would greatly be appreciated.

  


• ffmpeg overlay video on image and remove video black background

  15 septembre 2021, par Moslem Aslani

  Im using this ffmpeg command to overlay a video on image (with remove black background) :

  


  ffmpeg -loop 1 -i image.png -i video.mp4 -filter_complex [1:v]colorkey=0x000000:0.1:0.1[ckout];[0:v][ckout]overlay[out] -map [out] -t 5 -c:a copy -c:v libx264 -y result.mp4


  


  

  


  But as you can see in the picture, the black parts of the ball have also disappeared. How can I solve this problem ?

  


• How to get better video quality using Accord.Video.FFMPEG.DLL

  31 juillet 2023, par HighwayRob

  I have developed a Visual Studio Winapp that produces a video file utilizing Accord.Video.FFMPEG.DLL.

  


  The quality the video is less than the original images.
Here is the code and then a sample original image and snapshot of the resulting video.

  


  What can I change to improve the video image ?

  


              VideoFileWriter writer = new VideoFileWriter();
            writer.Open(outfile, width, height, 1, VideoCodec.Mpeg4);
            for (int i = firstrow; i <= testframes; i++)
            {
                Bitmap bitmap = new Bitmap(ffiles[i, 0].ToString());
                writer.WriteVideoFrame(bitmap);
                bitmap.Dispose();
            }


  


  I tried Bitmap image = new Bitmap(width, height, PixelFormat.Format64bppArgb) ;