Layer break for DVD+R DL with growisofs / dvd+rw-tools

I’ve started recently to play around with DVD+R DL because they start becoming cheaper and some applications really need them

I was very surprised that the current version of growisofs / dvd+rw-tools (7.1) advertises layer break position setting support but in reality I couldn’t get it to break where I want.

Looking at the code (especially from growisofs_mmc.cpp) I found very strange that the “-use-the-force-luke=break:NNNN” option wasn’t really used either in calculations or cuesheet sending.

Investigating a little bit more in the code I produced the following patch that I have sent upstream to get it included somehow in the next version.

It allows a user (who should be careful of what it does ) to manually force a layer break position for DVD+R DL burning. (For those of you who haven’t had this problem yet please notice that : DVD-R DL (minus) DO NOT allow layer position to be changed, that said you should know what to do … only DVD+R DL (plus) allow that)

For this patch to work you have to specify “-dvd-compat” on the command line, otherwise the cuesheet sending code is not called (I didn’t understand exactly why…) and the layer break wouldn’t be set …

In any case the output of growisofs command should tell you where the layer break is going to be set.

I’ve tested it succesfully for a dozen of DL burns with or without layer break so it should be safe enough (the patch is not very intrusive anyways ; I also tested without the option to see if the normal behavior was preserved…)

Use it this way :

growisofs -dvd-compat [your other options here] -use-the-force-luke=break:XXXX [where XXXX is the layer break in sectors] -Z /dev/[your device]=[image.iso]

for example :

growisofs -dvd-compat -use-the-force-luke=break:2084960 -use-the-force-luke=dao -Z /dev/sr0=/home/johndoe/m.iso

note the dao option usage that will close the session, otherwise the disc would remain “open” if it’s not full and depending on what you burn you’d really want to close the session trust me

Have an happy dual layer with positionned break burning !

Attachment : dvd+rw-tools-7.1-layerbreaksetup.patch

Note: use a command similar to apply (change to -p 1 depending on where you are) :

patch -p 0 < dvdrw-tools-7.1-layerbreaksetup.patch