Trim a video range out using ffmpeg

gistfile1.txt

#!/bin/bash

if ! [ "$#" = "3" ]
then
	echo "Usage: $0 [start-time] [end-time] [file-name]"
	echo
	echo "Trim out the file from start-time to end-time. 
	exit 1
fi

START=$(echo $1 | awk -F: '{ print ($1 * 3600) + ($2 * 60) + $3 }')
END=$(echo $2 | awk -F: '{ print ($1 * 3600) + ($2 * 60) + $3 }')
FILENAME=$3

DURATION=$(ffmpeg -i $FILENAME 2>&1 | grep Duration | awk '{ print $2 }')
DURATION=$(echo ${DURATION::-3})
DURATION=$(echo $DURATION | awk -F: '{ print ($1 * 3600) + ($2 * 60) + $3 }')
RANGE=$(( $DURATION - $END -1 ))

echo $START $END $DURATION $RANGE $FILENAME

ffmpeg -t $START -i $FILENAME -c copy tmpA-$FILENAME
ffmpeg -ss $END -t $DURATION -i $FILENAME -c copy tmpB-$FILENAME

echo "file '$PWD/tmpA-$FILENAME'" > tmp-files
echo "file '$PWD/tmpB-$FILENAME'" >> tmp-files

ffmpeg -f concat -safe 0 -i tmp-files -c copy trim-$FILENAME

rm tmp-files tmpA-$FILENAME tmpB-$FILENAME