Bash Move editing Script

Here is my script. It edits 20 seconds of a .mp4 and replaces the color white with cyan and black with blue and re-exports it as a new movie.
run the script and call the name of the movie you want to export after. ex.

./video.s movie

[

#!/bin/bash
$ffmpeg
#replaces white with cyan and black with blue
ffmpeg -i "$1".mp4 -ss 0 -vframes 600 "$1"%d.jpg

for i in {0..600}
  do
   
     convert "$1""$i".jpg  +level-colors blue,cyan "$1""-ex""$i".jpg   
    
    echo "making frame $i"

 done
ffmpeg -f image2 -i "$1""-ex"%d.jpg "$1"_export.mp4