LinuxQuestions.org - mass dvd conversion, need help and ideas

I did this a while ago with around 200 of my DVD's. As you've hinted at, I had the ripping and re-encoding separate. Here's how I did it:
-Use mplayer to dump the raw dvd mpeg data to a file.
-Use mencoder to do the re-encode.

These are the scripts I used. Put them into a ripping directory. To rip, run 'ripdvd NAME_OF_FILM titlenumber'. The main title number is usually 1, so it's the default if you don't supply a number. (You can do the other titles too if you want, just provide a different name, e.g. './ripdvd moviename-track1', './ripdvd moviename-track2' etc.

While you're ripping, start up (in a new terminal) the 'multiencode' script. It doesn't have any arguments. It basically keeps scanning the directory to see if there are any new files to encode. If there are, it does it. Otherwise it goes to sleep for a bit then checks again. I'd run it with a high nice value. You can start up multiple instances of the 'multiencode' script, if you've got multiple cpus or cores. They shouldn't interfere with each other.

Overall, it cut the effective encode time (that which I had to spend in front of the machine) to about 5 minutes per disc.

Okay, first the ripping script, which is dead simple

Code:

#!/bin/bash

#Arguments are name and title number (defaults to 1)

basename=$1

if [ $2 ]

 then 

  title=$2

 else

  title=1

fi



echo "Dumping title $title from $basename"

mplayer -dumpstream -dumpfile ${basename}.dump dvd://${title}

touch ${basename}-ready

Now the encoder

Code:

#!/bin/sh



#This sets some parameters for the encoding

targetsize=750  # Target size of the final xvid in MB

abitrate=192    # Audio bitrate (It'll come out as 2 channel 



vfscale='scale=640:-2'

vfhq='hqdn3d=2:1.5:3'

#vfpp='pp=ac/fd'

#vfilmdeint='filmdint'



#build up the global filter line here

vfbaseline="${vfscale},${vfhq}"



vhq=4



aid=128 #This is the default audio language (english) to extract.



#This returns the crop values from cropdetect. Args are filename and position (in frames)

function cropparams {

  cropval=$(mplayer -vo null -ao null -vf cropdetect $1 -ss $2 -frames 3 2>&1 \

 | grep 'crop=[0-9]\+:[0-9]\+:[0-9]\+:[0-9]\+' -o \

 | sed -e 's/crop=//' )

  echo $cropval

}



#This gets a load of crop values and picks the most common (best?) one

#parameters are $1=base name    $2=length of file

function getbestcrop {

cropstep=$(( ${2%.*} / 10 ))

length=${2%.*}



for (( x=0;x<=$length;x+=${cropstep%.*} ))

do

  cropparams ${1}.dump $x >> ${1}-crops

  uniquecrops=$( cat ${1}-crops | sort | uniq )

  for curcrop in ${uniquecrops}

  do

    curcount=$( grep -c ${curcrop} ${1}-crops )

    if [[ $curcount -gt $bestcount ]] 

      then 

        bestcount=$curcount

        bestcrop=$curcrop

      fi

  done  

done

rm ${1}-crops

echo $bestcrop

}



#**************************************************************************

#The main bit of the script. It loops endlessly, looking for new dump files

#**************************************************************************

while [ 1 ]

do



 #Get list of all FINISHED rips

 for cur in `ls *-ready`

 do

  curbase=${cur%-ready}



  #Have they been processed already? are they running at the moment?

  if [ -e ${curbase}-xvid.avi -o -e ${curbase}-working ]

  then

    echo " Not processing $curbase "

  else

    echo "Doing ${curbase}"

    touch ${curbase}-working

    vidlength=`midentify "${curbase}.dump" | grep 'ID_LENGTH=' | sed 's/ID_LENGTH=//'`

    cropparams=$(getbestcrop $curbase $vidlength)

    echo "Cropping parameters are $cropparams"

    vfcrop="crop=$cropparams"

    vfline="$vfcrop,$vfbaseline"



    echo "Current filters are $vfline"



#Calculate the bitrate

    audiosize=$(( $abitrate*1000*${vidlength%.*}/1024/1024/8 ))

    videosize=$(( ($targetsize-$audiosize)*1024 ))



    mencoder "${curbase}.dump" -ovc xvid -xvidencopts \

bitrate=-$videosize:vhq=$vhq:quant_type=h263:pass=1:turbo \

-vf "$vfline" -passlogfile "${curbase}-xvid.log" \

-oac copy -o /dev/null 



    mencoder "${curbase}.dump" -ovc xvid -xvidencopts \

bitrate=-$videosize:vhq=$vhq:quant_type=h263:pass=2 \

-vf "$vfline" -oac mp3lame -lameopts preset=$abitrate \

-aid $aid -passlogfile "${curbase}-xvid.log"  \

-o "${curbase}-xvid.avi"

  

  #Clean up

    rm ${curbase}-working

    rm ${curbase}-ready

    rm ${curbase}.dump

    rm ${curbase}-xvid.log

  fi

 done

echo "Going to sleep, nothing to do"

sleep 10



done

echo "All done"

I should say that the script is very far from perfect. The 'autocropping' is a bit ugly, but worked for most of my discs. The quality settings are okay, but you can get better (with a longer encode time). Also, you might need a deinterlace filter for some discs (I did).
You'll probably want to tweak some things in it, since it was for backing my dvds up onto a cd so I could watch on my divx player. You might want to change the file size, use a fixed bitrate or whatever. Also, this encodes into xvid, you might want something else.

There's plenty of other encoding scripts around, have a search of this site.
Anyway, it should give you the idea, hope it helps.