Extract every frame as single image

#!/bin/bash

T_NOW=`date +"%Y-%m-%d_%H-%M-%S"`
mkdir "$T_NOW"
ffmpeg -i input.mp4 -vsync 0 "$T_NOW"/%d.png

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Create video from frames

ffmpeg -framerate 25 -pattern_type glob -i '*.tif' \
  -c:v libx264 -r 25 -pix_fmt yuv420p out.mp4

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Merge 2 videos next to each other

ffmpeg \
  -i a.mp4 \
  -i b.mp4 \
  -filter_complex '[0:v]pad=iw*2:ih[int];[int][1:v]overlay=W/2:0[vid]' \
  -map [vid] \
  -c:v libx264 \
  -crf 23 \
  -preset veryfast \
  output.mp4

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