Crop a specified video file to the given x/y/width/height, with the same codec (will still necessarily re-encode).

crop

#!/bin/bash

roundmul() {
    lhs=$1
    denom=1
    case $lhs in
        *px)
            printf %.0f "${lhs%px}"
            return
            ;;
        *%)
            lhs="${lhs%\%}"
            denom=100
            ;;
    esac
    printf %.0f $(echo "scale=6; ($lhs) * ($2) / $denom" | bc)
}
rawprobe() {
    ffprobe -v -8 -show_entries "stream=$1" -of 'csv=p=0:s=\ ' "$2"
}
wh=($(rawprobe width,height "$1"))
w=${wh[0]}
h=${wh[1]}
codec=$(rawprobe codec_name "$1")
crop="$(roundmul $4 $w):$(roundmul $5 $h):$(roundmul $2 $w):$(roundmul $3 $h)"
outfile="${1%.*}.cropped.${1##*.}"
ffmpeg -i "$1" -c $codec -vf "crop=$crop" "$outfile"