New HP Drive Lets You Burn Your Own Label
way2trivial writes "Wow -- remember Yamaha's DiscT@2? now HP has a invention to use the DVD laser to etch the flip side of CDs and DVDs. I own a nice Epson to print on CD-R/DVD-Rs, it does full color -- but this looks impressive as hell, even if it is in monochrome"
To do so requires special writing capability in the drive itself, you not only need to be able to control the regular user data, you also need to be able to control all the bits that get generated in addition to regular user data. All the bits that are involved with the error correction, etc. This is why you don't see Yamaha type 'tattoos' with just any old drive, because Yamaha so far is the only manufacturer that gave you that much control over the drive. Without such deep control, I don't know how easy it would be to get your desired image, considering you normally have control over much less than half of how many bits are actually contained on a CD. I vaguely recall doing the math one day to see how many raw bits are on a CD, and I think it adds up to around 2GB of raw data to store your 700MB of user data. Very vaguely. Figures may be off, but it is in that ridiculous ballpark. And I'm not in the mood to go digging through specs. Basically, 2048 bytes of your data first goes to 2352 bytes, maybe another step here, and then every 8 bits gets translated to 14 bits encoded on the disc. Even just the 2048->2352 and 8->14 steps gives you almost 1407MB raw data for 700MB of user data.
The official website has more info and photos of labled disks.
Here is a PDF from HP all about it
The reason for the 8 -> 14 bit encoding is to make sure that long runs of 0's do not exist. If they did, the laser would be unable to follow the track accurately.
Predictive text is shiv!
For the other end, the consumable disc, an extra $0.10 has a huge fudge factor. Prices vary greatly so they're probably basing it upon the highest priced premium brand of DVD/CD-R (which isn't necessarily any better than the low cost cheepy-brand) so yes, you'll end up spending $10 for about 25 discs, while someone else is going to be paying $15 for a spindle of 100.
My biggest gripe (and you know I'll get flamed for saying this...): Since (I'm only guessing) it's all based in software, it will probably not be a feature availble to Linux users.
Looks like Sharpie isn't going to lose any of my business anytime soon. ;-)
The FAQ at: http://www.lightscribe.com/ says it can take 1-15 min to burn a label depending on how detailed the image is.
Beware of he who would deny you access to information, for in his heart he dreams himself your master. -Commissioner Lal