video-encode

#!/bin/bash

INFO="
Encode high quality videos using ffmpeg and the x264 codec.

Usage:
    video-encode [ <ffmpeg options> ] <output file>
"

if [ "x$1" = x -o "x$2" = x ]; then
    echo "$INFO" 1>&2
    exit 1
fi

OUTFILE=$(readlink -f "${!#}") || exit 1

if [ -e "$OUTFILE" ]; then
    echo "File '$OUTFILE' already exists!" 1>&2
    exit 1
fi

TMPDIR=$(mktemp -d) || exit 1
trap "rm -rf $TMPDIR" EXIT

echo "Extracting audio..."

ffmpeg -y -nostats -loglevel error \
    "${@:1:${#}-1}" \
    -vn "$TMPDIR/audio.wav" || exit 1

echo "Adjusting volume..."

VOL=$(sox "$TMPDIR/audio.wav" -n stat -v </dev/null 2>&1 >/dev/null | grep '^[0-9]') || exit 1
sox -Dv "$VOL" "$TMPDIR/audio.wav" "$TMPDIR/normalized.wav" </dev/null >/dev/null 2>&1 || exit 1

echo "Encoding with ffmpeg..."

ffmpeg -y -hide_banner -loglevel info \
    -i "$TMPDIR/normalized.wav" \
    "${@:1:${#}-1}" \
    -map 0:a -map 1:v \
    -codec:v libx264 -preset slow -crf 25 \
    -codec:a libmp3lame -q:a 5 \
    "$OUTFILE" || exit 1