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• I have created video using several images .. how to add fadein effect while every frame changing in video ? [duplicate]

  20 mai 2019, par Jeeva Murugan

  This question already has an answer here :

  • FFmpeg command for crossfading between 5 videos .How to manage setpts=PTS-STARTPTS ?
    
    1 answer
    

  I am running this code for creating video. How to add fadein effect for every frame in the video ?

  ffmpeg -r 2  -t 9 -pattern_type glob -i '*.png'  single_video.mp4

• Random PIPELINE_ERROR_DECODE : video decoder reinitialization failed on Chromium HTML5 video tag

  9 janvier 2024, par Hello World

  System

  


  Running an Expo React Native app, with a <webview></webview> component that loads a NextJS app with an HTML5 <video></video> tag. The system with issues is running the app on Android 9.0 with WebView implementation set to Android System WebView 84.0. The system without issues is running the app on Android 10.0 with WebView implementation set to Android System WebView 120.0.

  


  Details

  


  Video files being played by the <video></video> element are previously transcoded by the following fluent-ffmpeg node package :

  


  import ffmpeg from 'fluent-ffmpeg'

ffmpeg(rawVideoFileUrl)
  .videoCodec('libx264')
  .audioCodec('aac')
  .outputOption('-strict experimental')
  .outputOption('-movflags frag_keyframe+faststart')
  .format('mp4')


  


  My knowledge on video transcoding is very limited, but I have to do the transcoding to guarantee that the files are compatible to be played by my NextJS web app. In my research, my findings pointed to these FFMPEG command line arguments for my purpose.

  


  For the aforementioned WebView version, H.264 with AAC, should be compatible, yet playback is not stable. Many times it will play just fine, but other times I receive the error :

  


  PIPELINE_ERROR_DECODE: video decoder reinitialization failed


  


  If I refresh the web app, it works again. That leads me to believe it is somehow memory related, maybe caused by incompatibility.

  


  I'm not sure whether video decoder reinitialization failed produced by the HTML5 <video></video> tag is a problem of transcoding or not, as the videos play fine most of the time and only produces that error in the console some of the times, unexpectedly.

  


  Question

  


  Is there something that I can do to the fluent-ffmpeg command to make the video files more widely compatible, including the WebView 84.0 system too, or is the issue somewhere else ?

  


  In this case, updating WebView is not an option.

  


• AForge.Video.VideoFileWriter, Video Quality loss after a second

  29 décembre 2019, par Just another Dev

  I tried to use AForge to create mp4 video from images..but experience this quality loss after about 1 - 2 second into the video. Just wondering if anyone knows what went wrong with my code ?

  using AForge.Video.FFMPEG;
  
  VideoFileWriter writer = new VideoFileWriter();
  
  writer.Open(fileName, _width, _height, _frameRate, VideoCodec.MPEG4, 800000);
  
  var s = AForge.Imaging.Image.FromFile(@"[path]\image.jpg");
  
  int frameCount = _frameRate * scene.Time;
  
  for (int i = 0; i < frameCount; i++)
  
  {
  
      writer.WriteVideoFrame(s);
  
  }
  
  writer.Close();

  I use the above code to create a 3 second 1080p video with frame rate 60, bit rate 800k, and using this image as an example : https://www.bushandbeach.co.nz/wp-content/uploads/2019/05/A-Taste-of-Auckland-Full-Day-1-opt.jpg

  the output video is in here : https://youtu.be/j0z7711cyOM

  as you can see the image quality seems to be ok, for about 2 seconds and then it blurs out in the last second.

  Thanks so much