#!/bin/sh

USAGE='
Usage: brewdvd [-d <string>] [-ts <NN>] [-nn <N1> <N2>] [options] -o <string>

Based on mencoder and lsdvd.

Check dvd content with:
$ mplayer -frames 0 -identify -dvd-device /dev/sr0 dvd://
$ lsdvd <dvd-path>

Check AVI file content with:
$ mediainfo <avi-file>

Copyright © Daniel Ljunggren <foto@demulsion.se>. Version 0.5 Aug 2009 - Sep 2014.

[options]:

-d <string>         : directory with VOB files or dvd-device (default /dev/sr0)
-ts <NN>            : video title set of the format VTS_ts_nn.VOB
-nn <N1> <N2>       : span of dvd titles (default is longest dvd title) or if -ts set then
                      span of video objects (format VTS_ts_N1.VOB to VTS_ts_N2.VOB)

-ac3                : use AC3 audio coding (default is MP3)
-mpeg4              : use MPEG-4/DIVX (proprietary) video coding (default is Xvid open source)
-ca                 : copy audio format from source
-cv                 : copy video format from source

-m <value>          : film length in minutes (set vbitrate targeting 700 MiB)
-i                  : deinterlacing filter (changes framerate from 50 to 25 fps)
-a <value>          : aspect ratio (4/3, 16/9), default is autoaspect
-split              : split each title into separate file
-skip <value>       : skip first N (try N=1) seconds (fixes some problems with de/encoding)
-noalang            : no audio language selection (fixes some problems with de/encoding)
-vol                : increase volume by 12dB (default 3dB)

-o <string>         : output filename
'

# Problems: 

# No sound on dvd://1, but dvd://2 dvd://3 ok: (-alang has effect, -aid works)
# $brewdvd -d Spökar_Alfons_DVD4/ -nn 1 3 -ca -cv -o test.avi

# Works ok: (-alang has no effect, -aid works)
# $brewdvd -d Spökar_Alfons_DVD4/ -ts 01 -nn 1 3 -ca -cv -o test.avi

# Best is lossy video and audio with Alfons:
# $brewdvd -d Spökar_Alfons_DVD4/ -ts 01 -nn 1 3 -o test.avi

# "Cannot mix video-only..." (dvd1 no swedish found) "...with audiovideo" (dvd2 swedish ok)
# or "All video files must have identical fps, resolution, and codec for -ovc copy" with option -ffourcc MPEG
# $mencoder -ss 1 -alang sv -dvd-device Spökar_Alfons_DVD4/ dvd://1 dvd://2 -oac copy -ovc copy -o test.avi

# Gives finish language (alang to late):
# $mencoder -ss 1 -dvd-device Spökar_Alfons_DVD4/  dvd://1 dvd://2  -oac copy -alang sv,en -ovc copy -o test.avi

# This playes swedish
# $mplayer -alang sv -dvd-device Spökar_Alfons_DVD4/ dvd://1 

# This does not play swedish
# $mencoder -alang sv -dvd-device Spökar_Alfons_DVD4/ dvd://1  -oac copy -ovc copy -o test.avi

SPLITFILES=false
SKIP=1
TS=""
NS=""
NE=""
ASPECT="autoaspect"
FILTEROPTS="-vf harddup"
VOBFILE=false
AFORMAT=MP3
VFORMAT=XVID
MINUTES=""
VBITRATE=1800 # Minimum video bitrate kbit/s
ABITRATE=320 # DVD standard seems to be 448 kbit/s, half bitrate is 224 kbit/s
TARGETMiB=700
SKIPFRAMES=false
DVDDEVICE=/dev/sr0
NOALANG=false
VOL=false
OPTIONS="-nosub -noautosub" # No subtitles

# Define a calculator with max() and min() based on awk 
function calc () {
    awk "function max(a, b) { if (a > b) {return a} else {return b} };
               function min(a, b) { if (a < b) {return a} else {return b} };
               BEGIN { print $* ; }"
}

if [ $# -eq 0 ]; then echo "${USAGE}" ; exit 1; fi

while [ $# -gt 0 ]
  do
  case "$1" in
      -d)
	  DVDDEVICE=$2
	  shift 1
	  ;;
      -ts)
	  VOBFILE=true
	  TS=$2
	  shift 1
	  ;;
      -ac3)
	  AFORMAT=AC3
	  ;;
      -mpeg4)
	  VFORMAT=DIVX
	  ;;
      -ca)
	  AFORMAT=COPY
	  ;;
      -cv)
	  VFORMAT=COPY
	  ;;
      -nn)
	  NS=$2
	  NE=$3
	  shift 2
	  ;;
      -m)
	  MINUTES=$2
	  shift 1
	  ;;
      -i)
	  FILTEROPTS="$FILTEROPTS -vf yadif=0"
	  ;;
      -a)
	  ASPECT="aspect=$2"
	  shift 1
	  ;;
      -skip)
	  SKIPFRAMES=true
	  SKIP=$2
	  shift 1
	  ;;
      -split)
          SPLITFILES=true
          ;;
      -noalang)
	  NOALANG=true
	  ;;
      -vol)
	  VOL=true
	  ;;
      -o)
	  FILENAME=$2
	  shift 1
	  ;;
      -help)
          echo "${USAGE}"
          exit 0
          ;;
      *)
          OPTIONS="${OPTIONS} $1"
          ;;
      #*)
      #    break
      #    ;;
  esac
  shift 1
done

VOB_EXT=VOB
ORIG_EXT=avi

# Find default title to encode
if [ $VOBFILE == 'false' ] && [ -z $NS ]; then
    NS=`lsdvd ${DVDDEVICE} | grep Longest | cut -b16-`
    if [ -z $NS ]; then NS=1; fi
    NE=$NS
elif [ -z $NS ]; then
    NS=1
    NE=$NS
fi

# Calculate needed video bitrate based on audio bitrate and target file size.
if [ ! -z $MINUTES ]; then
    # VBITRATE_T=$(calc "8*1024*$TARGETMiB/(${MINUTES}*60)") # Ignore audio bitrate
    VBITRATE_T=$(calc "int((1024*1024*$TARGETMiB-$ABITRATE*1000*60*${MINUTES}/8)*8/(60*${MINUTES}*1000))")
    echo "Variable bitrate is $VBITRATE_T kbit/s"
else
    VBITRATE_T=0
fi

VBITRATE=$(calc "max(${VBITRATE_T},${VBITRATE})")

if [ $AFORMAT == 'AC3' ]; then  #
    AUDIOSWITCH="-oac lavc -lavcopts acodec=ac3:abitrate=${ABITRATE}" # Surround sound
elif [ $AFORMAT == 'MP3' ]; then 
    AUDIOSWITCH="-oac mp3lame -lameopts abr:br=${ABITRATE}:aq=0" # Stereo sound
    #AUDIOSWITCH="$AUDIOSWITCH:vol=8" # Volume gain specific for mp3.
elif [ $AFORMAT == 'COPY' ]; then
    AUDIOSWITCH="-oac copy"
    #AUDIOSWITCH="-oac pcm"
    SKIPFRAMES=true # Avoid segmentation fault in mencoder
fi

if [ $VFORMAT == 'DIVX' ]; then  # MPEG-4/DIVX
    VIDEOSWITCH="-ovc lavc -lavcopts vcodec=mpeg4:vbitrate=${VBITRATE}:vhq:${ASPECT}:turbo:v"
elif [ $VFORMAT == 'XVID' ]; then  # XVID
    VIDEOSWITCH="-ovc xvid -xvidencopts bitrate=${VBITRATE}:${ASPECT}:turbo:"
    #OPTIONS="${OPTIONS} -ffourcc XVID"
elif [ $VFORMAT == 'COPY' ]; then
    VIDEOSWITCH="-ovc copy"
    #if [ $VOBFILE == "false" ]; then
    #OPTIONS="${OPTIONS} -ffourcc MPEG"
    #fi
fi

if [ $NOALANG == 'false' ] && [ $VOBFILE == 'false' ]; then
    AUDIOSWITCH="$AUDIOSWITCH -alang sv,en" # alang only works with -dvd-device and dvd://...
fi

if [ $SKIPFRAMES == 'true' ]; then
    FILTEROPTS="$FILTEROPTS -ss $SKIP"
fi

if [ $VOL == 'true' ]; then
    # Normalize sound volume, moving average compression.
    #FILTEROPTS="$FILTEROPTS -af volnorm"    
    # Increase volume 12 dB
    FILTEROPTS="$FILTEROPTS -af volume=12"
else
    FILTEROPTS="$FILTEROPTS -af volume=3"
fi

OPTIONS="-dvd-device $DVDDEVICE ${OPTIONS}"

if [ $SPLITFILES == 'false' ]; then
    for (( N = $NS; N <= $NE; N++ ));
    do
	if [ $VOBFILE == 'true' ]; then
	    #SOURCEDIR=`dirname $SOURCENAME`
	    #SOURCEBASE=`basename $SOURCENAME .$VOB_EXT`
	    INPUT="$INPUT $DVDDEVICE/VTS_${TS}_${N}.$VOB_EXT"
	else
	    INPUT="$INPUT dvd://${N}"
	fi
    done

    echo "Options: $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH} ${OPTIONS} $INPUT -o ${FILENAME}"
    if [ $VFORMAT == 'COPY' ]; then
	mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH} ${OPTIONS} $INPUT -o ${FILENAME}
    else
	#mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH} ${OPTIONS} $INPUT -o ${FILENAME} 
	mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH}pass=1 ${OPTIONS} $INPUT -o ${FILENAME}    
	mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH}pass=2 ${OPTIONS} $INPUT -o ${FILENAME}  
	rm divx2pass.log
    fi
else
    for (( N = $NS; N <= $NS; N++ ));
    do
	if [ $VOBFILE == 'true' ]; then
	    #SOURCEDIR=`dirname $SOURCENAME`
	    #SOURCEBASE=`basename $SOURCENAME .$VOB_EXT`
	    INPUT="$INPUT $DVDDEVICE/VTS_${TS}_${N}.$VOB_EXT"
	else
	    INPUT="dvd://${N}"
	fi
	DIR=`dirname $FILENAME`
	BASE=`basename $FILENAME .$ORIG_EXT`
	NEWFILENAME="${DIR}/${BASE}_${N}.${ORIG_EXT}"

	if [ $VFORMAT == 'COPY' ]; then
	    mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH} ${OPTIONS} $INPUT -o ${NEWFILENAME}
	else
	    mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH}pass=1 ${OPTIONS} $INPUT -o ${NEWFILENAME}
	    mencoder $FILTEROPTS ${AUDIOSWITCH} ${VIDEOSWITCH}pass=2 ${OPTIONS} $INPUT -o ${NEWFILENAME}
	    rm divx2pass.log
	fi
    done    
fi