#!/usr/bin/env bash

if [[ "$1" == "-h" || "$1" == "--help" ]]; then
    cat <<EOF
Usage: $(basename "$0") [-h] <input.mp4>

Compress MP4 video using ffmpeg.

Options:
    -h, --help    Show this help message

Arguments:
    input.mp4     Input video file (must be .mp4)

Output:
    <input>_compressed.mp4

EOF
    exit 0
fi

filename="${1%.mp4}"
ffmpeg \
    -i "$filename".mp4 \
    -c:v libx264 \
    -crf 28 \
    -preset veryslow \
    -c:a aac \
    -b:a 128k \
    "$filename"_compressed.mp4