##!/bin/bash
set -u
#
#   <input VOB directory> <output filename>
#
#-----------------------------------------------------------------
# get a list of all the VOBS, exluding the menu - VTS_xx_0.VOB
vobs_list=$(find "${1}" -type f -name 'VTS_[0-9][0-9]_[1-9].VOB' | sort)

# check if any VOB files found
if [[ -z ${vobs_list} ]]
then
    echo "${movie_path} : No VOB files found"
    return 1
fi

#-----------------------------------------------------------------
# set the file separator to newline to for the list of vobs
oIFS="${IFS}"
IFS=$'\n'

#--------------------------FFMPEG---------------------------------------
# -map 0                       // to capture all streams
# -map -dn                     // ignore all data channels (used for dvd menus?), (prevents ffmpeg error)
# -c:v libx264                      // video encoding to h264
# -crf 18                           // video, almost loss-less
# -c:a copy                         // copy audio stream as is
# -c:s copy                         // copy subtitle stream as is
# -preset fast                         // best output file size (compression ratio) in reasonable
# -analyzeduration 50M -probesize 50M  // to make sure subtitle is found correctly

TIMEFORMAT='Elapsed time %R seconds'
time {
    cat ${vobs_list} | \
    ffmpeg \
        -y \
        -analyzeduration 50M \
        -probesize 50M \
        -i - \
        -map 0 \
        -map -dn \
        -c:v libx264 \
        -c:a copy \
        -c:s copy \
        -preset fast \
        -crf 18 \
        "${2}"
    exit_status=$?
}

#-----------------------------------------------------------------
# reset the file separator to original
IFS="${oIFS}"