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• Remove video noise from video with ffmpeg without producing blur / scale down effect

  17 avril 2024, par Sucahyo Aji

  My videos are 1920x1080 recorded with high ISO (3200) using smartphone (to get bright view, backlight scene mode). It produce a lot of noise. I try many video filter but all of them produce blur similar to when we reduce the resolution in half then increase it back again.

  


  Is there a good video noise filter that only remove noise without producing blur ?

  


  Because if it produce blur, I would prefer to not do any filtering at all.

  


  I have tried video filter :

  


  


  • nlmeans=s=30:r=3:p=1

    


  


  • vaguedenoiser=threshold=22:percent=100:nsteps=4

    


  


  • owdenoise=8:6:6

    


  


  • hqdn3d=100:0:50:0

    


  


  • bm3d=sigma=30:block=4:bstep=8:group=1:range=8:mstep=64:thmse=0:hdthr=5:estim=basic:planes=1

    


  


  • dctdnoiz=sigma=30:n=4

    


  


  • fftdnoiz=30:1:6:0.8

    


  


  


  All produce blur, some even worse. I have to use strong setting to make the noise moderately removed. I end up halving the resolution and use remove grain then scale it up again. This is much better for me than all the above method (pp filter is used to reduce size without reducing image detail) :

  


  

  • scale=960:540,removegrain=3:0:0:0,pp=dr/fq|8,scale=1920:1080

  


  


  code example

  


  FOR %%G IN (*.jpg) DO "ffmpeg.exe" -y -i "%%G"  -vf "nlmeans=s=30:r=3:p=1" -qmin 1 -qmax 1 -q:v 1   "%%G.jpg"

  


  Part of the image
  
The image:

  


• avconv/ffmpg generating frames in php

  6 mars 2014, par fsulser

  I'm trying to generate some frames (at the moment) on my localhost server with this code :

  $cmd = 'avconv -i "../videos/medium.mp4" -vsync 1 -r 10 -f image2 -an -y -qscale 20 -s 120*90 -ss 00:00:05 -t 00:00:10 "out_%05d.jpg" 2>&1';
  
  
  
  passthru($cmd, $out);

  I get the following message :

  avconv version 0.8.10-4:0.8.10-0ubuntu0.12.04.1, ............
  Press ctrl-c to stop encoding [image2 @ 0x646120] Could not open file : out_00001.jpg av_interleaved_write_frame() : Input/output error failed1

  The problem is if I run this command in my terminal it works. Does anyone know whats the problem ? Is it due to permisson or something else ?

• Is there a faster way to generate video from pixel arrays using python and ffmpeg ?

  8 mai 2019, par devneal17

  I’ve found a few sources which use python and ffmpeg to generate video from pixel arrays by passing the -f rawvideo flag 1 2. However, this is very slow for high-definition video since each individual pixel must be piped into ffmpeg.

  In fact this is provably wasteful, as I’ve found that 2.5Gb of pixel arrays generates about 80Kb of video. I’ve also chanced upon some examples where javascript can render high quality animations in near-real time 1, which makes me even more suspicious that I’m doing something wrong.

  Is there a way to do this more efficiently, perhaps by piping the differences between pixel arrays into ffmpeg rather than the pixels themselves ?

  (edit) This is the line I’m using. Most executions take the else path that follows.