A wrapper script for `transcode-video` with an experimental average bitrate (ABR) ratecontrol system.

experimental-abr-transcode-video.sh

#!/bin/bash
#
# experimental-abr-transcode-video.sh
#
# Copyright (c) 2013-2017 Don Melton
#

die() {
    echo "$(basename "$0"): $1" >&2
    exit ${2:-1}
}

args=()
blu_ray=''
dvd=''
blu_ray_bitrate='6000'
dvd_bitrate='1500'
bitrate=''

while [ "$1" ]; do
    case $1 in
        --blu-ray|--bluray)
            blu_ray='yes'
            dvd=''
            bitrate=''
            ;;
        --dvd)
            blu_ray=''
            dvd='yes'
            bitrate=''
            ;;
        --big)
            blu_ray_bitrate='8000'
            dvd_bitrate='2000'
            bitrate=''
            ;;
        --small)
            blu_ray_bitrate='4000'
            dvd_bitrate='1000'
            bitrate=''
            ;;
        --bitrate)
            bitrate="$2"
            shift
            ;;
        --abr)
            ;;
        --target|--cvbr|--vbr)
            die "unsupported argument: $1"
            ;;
        *)
            args=("${args[@]}" "$1")
            ;;
    esac
    shift
done

if [ ! "$bitrate" ]; then

    if [ "$blu_ray" ]; then
        bitrate="$blu_ray_bitrate"

    elif [ "$dvd" ]; then
        bitrate="$dvd_bitrate"
    else
        die 'missing argument: must include `--blu-ray`, `--dvd` or `--bitrate`'
    fi
fi

transcode-video \
    --abr \
    --target $bitrate \
    --encoder-option _qpmax \
    --encoder-option vbv-maxrate="$((bitrate + (bitrate / 2)))" \
    --encoder-option vbv-bufsize="$((bitrate * 2))" \
    --encoder-option nal-hrd=vbr \
    "${args[@]}"

exit $?