Get info about DVD burner in Python

[Nevon]

I'm currently rewriting an application that I made to burn Xbox 360 isos (really just a front-end to growisofs) in Python, and giving it a proper GUI. However, right now I'm kind of stuck, trying to get information about the user's optical media.

First of all I need to be able to list all optical devices with writing capabilities. Then I would need to find out whether or not the devices have any discs in them. Lastly I would need to find out what kind of discs are in the devices.

I've been googling for the last half-hour or so, but I can't come up with anything. Is there a simple way to solve this?

[jeffathehutt]

I know it doesn't directly answer your question, but you might get some ideas from the source code for recorder. (http://code.google.com/p/recorder/) (http://code.google.com/p/recorder/) It is a frontend to growisofs written in python. You might be able to see how that program does it. Hope that helps a bit.

[Nevon]

I know it doesn't directly answer your question, but you might get some ideas from the source code for recorder. (http://code.google.com/p/recorder/) (http://code.google.com/p/recorder/) It is a frontend to growisofs written in python. You might be able to see how that program does it. Hope that helps a bit.

Checked it out, but it turns out that program gets any info about the drive from the user - so for me it's useless. However, I did check out wodim, and it seems you can use:

wodim --devicesto get a list of drives, looking something like this:

wodim: Overview of accessible drives (1 found) :
-------------------------------------------------------------------------
0 dev='/dev/scd0' rwrw-- : 'Optiarc' 'DVD RW AD-7590S'
-------------------------------------------------------------------------
Now the question is, how do I get information about the drive - like maximum write speed, what discs it can handle, etc. As well as information about the disc inside?

Basically I want the same sort of functionality that Brasero has. See the picture for an idea.

http://i26.tinypic.com/wn47n.png

And here's BoxBlaze in it's current form:

http://i27.tinypic.com/2wn713r.png

Of course I could try to see what Brasero is doing, but first of all it's pretty darn big. And secondly, it's not written in Python.

[Nevon]

Hey! Now we're talking! Wodim can do more than you'd think.

To get more information about the drive itself (like burn speeds and such), you can do (remember, I got the device mount point from "wodim --devices":

nevon@loltop:$ wodim -prcap dev=/dev/scd0
wodim: Operation not permitted. Warning: Cannot raise RLIMIT_MEMLOCK limits.Device type : Removable CD-ROM
Version : 5
Response Format: 2
Capabilities :
Vendor_info : 'Optiarc '
Identification : 'DVD RW AD-7590S '
Revision : '1.00'
Device seems to be: Generic mmc2 DVD-R/DVD-RW.

Drive capabilities, per MMC-3 page 2A:

Does read CD-R media
Does write CD-R media
Does read CD-RW media
Does write CD-RW media
Does read DVD-ROM media
Does read DVD-R media
Does write DVD-R media
Does read DVD-RAM media
Does write DVD-RAM media
Does support test writing

Does read Mode 2 Form 1 blocks
Does read Mode 2 Form 2 blocks
Does read digital audio blocks
Does restart non-streamed digital audio reads accurately
Does support Buffer-Underrun-Free recording
Does read multi-session CDs
Does read fixed-packet CD media using Method 2
Does not read CD bar code
Does read R-W subcode information
Does not return R-W subcode de-interleaved and error-corrected
Does read raw P-W subcode data from lead in
Does return CD media catalog number
Does return CD ISRC information
Does support C2 error pointers
Does not deliver composite A/V data

Does play audio CDs
Number of volume control levels: 0
Does not support individual volume control setting for each channel
Does not support independent mute setting for each channel
Does not support digital output on port 1
Does not support digital output on port 2

Loading mechanism type: tray
Does support ejection of CD via START/STOP command
Does not lock media on power up via prevent jumper
Does allow media to be locked in the drive via PREVENT/ALLOW command
Is not currently in a media-locked state
Does not support changing side of disk
Does not have load-empty-slot-in-changer feature
Does not support Individual Disk Present feature

Maximum read speed: 8310 kB/s (CD 47x, DVD 6x)
Current read speed: 8310 kB/s (CD 47x, DVD 6x)
Maximum write speed: 8310 kB/s (CD 47x, DVD 6x)
Current write speed: 8310 kB/s (CD 47x, DVD 6x)
Rotational control selected: CLV/PCAV
Buffer size in KB: 2048
Copy management revision supported: 1
Number of supported write speeds: 3
Write speed # 0: 8310 kB/s CLV/PCAV (CD 47x, DVD 6x)
Write speed # 1: 5540 kB/s CLV/PCAV (CD 31x, DVD 4x)
Write speed # 2: 3324 kB/s CLV/PCAV (CD 18x, DVD 2x)

Supported CD-RW media types according to MMC-4 feature 0x37:
Does write multi speed CD-RW media
Does write high speed CD-RW media
Does write ultra high speed CD-RW media
Does write ultra high speed+ CD-RW media

And to get information about the media inside, I just do:

nevon@loltop:$ dvd+rw-mediainfo /dev/scd0
INQUIRY: [Optiarc ][DVD RW AD-7590S ][1.00]
GET [CURRENT] CONFIGURATION:
Mounted Media: 2Bh, DVD+R Double Layer
Media ID: MKM/003
Current Write Speed: 6.0x1385=8310KB/s
Write Speed #0: 6.0x1385=8310KB/s
Write Speed #1: 4.0x1385=5540KB/s
Write Speed #2: 2.4x1385=3324KB/s
GET [CURRENT] PERFORMANCE:
Write Performance: 2.4x1385=3324KB/s@[0 -> 393215]
4.0x1385=5540KB/s@[393216 -> 1114111]
6.0x1385=8310KB/s@[1114112 -> 4173824]
Speed Descriptor#0: 00/4173824 R@6.0x1385=8310KB/s W@6.0x1385=8310KB/s
Speed Descriptor#1: 00/4173824 R@6.0x1385=8310KB/s W@4.0x1385=5540KB/s
Speed Descriptor#2: 00/4173824 R@6.0x1385=8310KB/s W@2.4x1385=3324KB/s
READ DVD STRUCTURE[#0h]:
Media Book Type: 00h, DVD-ROM book [revision 0]
Legacy lead-out at: 2086912*2KB=4273995776
DVD+R DOUBLE LAYER BOUNDARY INFORMATION:
L0 Data Zone Capacity: 2086912*2KB, can still be set
READ DISC INFORMATION:
Disc status: blank
Number of Sessions: 1
State of Last Session: empty
"Next" Track: 1
Number of Tracks: 1
READ TRACK INFORMATION[#1]:
Track State: blank
Track Start Address: 0*2KB
Next Writable Address: 0*2KB
Free Blocks: 4173824*2KB
Track Size: 4173824*2KB
ROM Compatibility LBA: 0
READ CAPACITY: 0*2048=0

Now I just need to parse this. Too bad I suck at regular expressions. Anyone with mad regexp skills who would like to help me? First I need to get the device mount point as well as the name. That is, everything inside ''s in the output of wodim --devices.

Next would be to find out whether or not the burner supports burning of dual layer discs, but it doesn't seem like wodim checks for that.

At least I can check for supported drive speeds. Basically, this is what I need:

Number of supported write speeds: 3
Write speed # 0: 8310 kB/s CLV/PCAV (CD 47x, DVD 6x)
Write speed # 1: 5540 kB/s CLV/PCAV (CD 31x, DVD 4x)
Write speed # 2: 3324 kB/s CLV/PCAV (CD 18x, DVD 2x)
Or well, I really just need the numbers before kB/s.

Last of all we have the output of dvd+rw-mediainfo /dev/scd0 where I'm only looking for "DVD+R Double Layer" after "Mounted Media:", and "Disc status: blank". If it's already been used, it should say "appendable" or something other than "blank".