compress video with ffmpeg

compressvideo.sh

#!/bin/sh

# check $1 and $2
if [ -z "$1" ] || [ -z "$2" ]; then
    echo "Usage: $0 <input_file> <output_file>"
    exit 1
fi

# check if $1 is a file
if [ ! -f "$1" ]; then
    echo "Error: $1 is not a file"
    exit 1
fi

ffmpeg -i $1 -c:v libx264 -crf 18 -preset veryslow -c:a copy $2