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• Combine multiple images into a video using ffmpeg [closed]

  13 avril 2021, par Mayank Thapliyal

  I want to combine multiple images into a video. I will use ffmpeg with Python as Python script will help me select images accordingly. And I have to fulfill multiple conditions :

  


  


  1. Frame-rate will be 0.2 (5 second for each image).

     


  


  2. Screen-Ratio should be 18:9. But all images have different dimensions. And neither I want to crop nor I want to stretch them. So I want to pad them with a black background.

     


  


  3. Ability to add background music.

     


  


  


  But the issue is that I am not able to adjust images. Either images get stretched to full screen or they get cropped. So currently first I use PIL library to adjust images first then combine them with ffmpeg. But it takes a good amount of time and I don't like this approach.

  


  Please help me solve my issue by only using ffmpeg (I guess that it will be fast enough).

  


• How to stream the video from one PC to another with an acceptable quality and synchronization ?

  15 juin 2021, par ErickSkrauch

  I have the following task : to organize the broadcast of several gamers on the director's computer, which will switch the image to, to put it simply, the one who currently has more interesting gameplay.

  


  The obvious solution would be to raise an RTMP server and broadcast to it. We tried that. The image quality clearly correlates with the bitrate of the broadcast, but the streams aren't synchronized and there is no way to synchronize them. As far as I know, it's just not built into the RTMP protocol.

  


  We also tried streaming via UDP, SRT and RTSP protocols. We got minimal delay but a very blurry image and artifacts from lost packets. It feels like all these formats are trying to achieve constant FPS and sacrifice the quality.

  


  What we need :

  


  

  • A quality image.

  


  • Broken frames can be discarded (it's okay to have not constant FPS).

  


  • Latency isn't important.

  


  • The streams should be synchronized within a second or two.

  


  


  There is an assumption that broadcasting on UDP should be a solution, but some kind of intermediate buffer is needed to provide the necessary broadcasting conditions. But I don't know how to do that. I assume that we need an intermediate ffmpeg instance, which will read the incoming stream, buffer it and publish the result to some local port, from which the picture will be already taken by the director's OBS.

  


  Is there any solution to achieve our goals ?

  


• How to introduce artificial noise in the videos using ffmpeg ?

  17 juin 2021, par ashish14

  I am trying to introduce artificial noise in the videos so as to simulate real-world behaviour. The sources of noise I am currently considering are :

  


  

  1. Quality of video

     

     • Modifying video properties such as frame rate, resolution, bit rate, codecs and compression.

     


     


  


  2. Recording Conditions

     

     • Factors such as lighting, brightness, contrast, darkness, blurriness, color etc.

     


     


  


  


  So far I have tried changing the brightness to replicate different lighting settings. I used this command
ffplay -vf eq=gamma=1.5:brightness=0.3:saturation=20 P2_Frontal_3_A.MP4 to change the values of brightness.

  


  Questions :

  


  

  • Does modifying the brightness like above make sense to simulate different lighting conditions ?

  


  • What other properties should I change for blurriness, contrast and darkness ?