A short bash script that slices video into 20 second clips

slice-video.sh

#!/bin/bash

# Usage: ./slice-for-stories.sh Video-to-Slice.mp4

fname=$1

# Get length
length=$(ffmpeg -i $fname 2>&1 | grep "Duration"| cut -d ' ' -f 4 | sed s/,// | sed 's@\..*@@g' | awk '{ split($1, A, ":"); split(A[3], B, "."); print 3600*A[1] + 60*A[2] + B[1] }')
let fcount=length/20
echo "${fname} is ${length}s long. About to create ${fcount} files..."

# Loop through each file
counter=0
while [ $counter -le $fcount ]
do
    newfname="$fname-$counter.mp4"
    let newstart=counter*20

    echo "Creating ${newfname} starting at ${newstart}"
    ffmpeg -i $fname -ss $newstart -t 20 $newfname

    ## Crop the video as well
    # ffmpeg -i $fname -filter:v "crop=in_h*9/16:in_h" -ss $newstart -t 20 $newfname

    ((counter++))
done