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Another discussion on this very topic- includes the potential dip switch settings to get MUZAK equipment to play Red Book CDs.

The previous link led me to suspect Green Book as the format for Muzak. CD-Interactive Spec

CD-I Bridge: A program that reads Green Book Formats

So it looks to me like you have two options- fiddle with the dip switches to find a setting that will allow you to play Red Book CDs, or find a program that allows you to write CD-Interactive Green Book Format discs.

Here's another reference to the capacity of a DVD-ROM.. Older, I know.

Roughly 15 gigs per layer my friend.

Sure they're prohibitively expensive but if you truly want a high capacity permanent archival storage medium, DVD glass masters stored in their special cases can survive extreme light, heat, and evil spirits: http://www.disctronics.co.uk/technology/manuf/rep_ master.htm#Glass%20Master%20Preparation

Sure they're prohibitively expensive but if you truly want a high capacity permanent archival storage medium, DVD glass masters stored in their special cases can survive extreme light, heat, and evil spirits: http://www.disctronics.co.uk/technology/manuf/rep_ master.htm#Glass%20Master%20Preparation

Take a look at CPRM, AACS is quite similar.

Slate.com covered this a couple of days ago, ultimately giving the Blu-Ray the nod over HD-DVD. The article also links to this useful comparison chart.

So I have some more links for y'all.

Technology News' Report and PCWorld's Article on the new disc that will contain a backwards-compatible (4.6 GB) DVD layer and a higher definition (15 GB) HD-DVD layer of which production is planned to begin in October or November of next year.

This seems like this could be a major factor in the format war between HD-DVD and the higher capacity Blu-ray.

Sorry, I made some factual errors (just some info I had incorrectly remembered from a long time ago), but the overall argument remains intact. Actually, the numbers I quoted are reversed. Blue-Ray has a 0.1mm cover layer (depth of data layer from transparent surface), while HD-DVD has a 0.6mm cover layer, which is the same as DVDs and CDs, and can therefore be manufactured using existing equipment. More info here.

How on Earth are users supposed to choose between DVD-A and DVDA? It simply baffles me.

Making a bunch of "custom" disk that can only be played by a specific player can be done fairly cheaply.You just have to use the barcode scheme that's already used in the copy protection scheme of Gamecube disk.

Barcodes on the burst cutting area

Basicly a barcode is burned onto the leadin area of the disk after coping it is complete. You just burn the serial code of the player this disk will play on and the player is equiped to only play those disk with matching serial numbers.

Other vital information could be burned into this barcode such as the decryption key, or the start of the TOC because most players and all consumer DVD burners cannot read or reproduce this data. It renders the disk unreadable.

Sony DL Info

DVD Formats

Disc Max User Capacity Note
120 mm :DVD5 4.7GB Single layer Single sided disc
120 mm :DVD9 8.5GB Double layer Single sided disc
120 mm :DVD10 9.4GB Single layer Double sided disc
120 mm :DVD18 17.1GB Double layer Double sided disc
120 mm :DVD-R 4.7 GB Single layer Single sided disc
120 mm :DVD-RW 4.7 GB Single layer Single sided disc
120 mm :DVD+RW 4.7 GB Single layer Single sided disc

TKM

I received two audio CD's with so called 'copy protection' on them for christmas. I wasn't able to play the CDs on the PC without lots of skipping, but I was able to rip them (perfectly - as far as I can tell) without any problems or specialist software.

After reading about how copy protection works, I can only assume that I must be lucky enough to own a drive that can read these disks?

Here's one for you: DVD Audio a.k.a CPPM. Out since 2000, not cracked yet, revocation of cracked devices possible.

you cant make a sequential serial number in the discs as you press them. they can do it in printing, and maybe have the laser read a barcode, but in the pressing process? no way.

With DIVX discs, GameCube discs, and some DVD-ROM titles, the barcode is put in between pressing and printing. Learn more about the Burst Cutting Area

DVDs are not just an extended CD technology.Copy protection is built into the standard.And Hollywood sort of decided the standard.
Which is why DVD-R are not an easy thing.

a nice resource on all the supported cd book formats.

• Philips introduces the audio cassette in 1963.
• 1963+17=1980.
• CD-audio format introduced in 1982. Philips and Sony are the major companies involved.
• 1982+17=1999
• DVD format introduced in 1995 (Philips/Sony, Toshiba & Warner), with US launch in 1997 and DVD-audio(1.0) by 1999.

... is CPPM, cousin of CPRM. It is interesting in the way that it has revocation of hacked devices built in. A quick overview is here, but there is much more info available on the net.

This page
AND
This page
explain there are only double sided DVD-Rs which would add up to your 9.4GB, there are no dual layer Recordables just yet. But I'm sure somebody will come up with a way to make them, right?

When DVDs are burned and read, you don't simply read raw data off. The information is, of course, encoded. The DVD (and CD for that matter) specification says to use Reed-Solmon encoding. Saving the long math, RS encoding is about the most advanced error-correcting scheme that can be implemented in low-cost hardware today. By encoding data this way, your DVD (or CD) can become fairly scratched, but still play. RS protects against multiple-point errors. However, there is a price to pay - for every ~33k byte block on a DVD, almost 5K bytes are used in the parity checks for the DVD. See this file for more gritty details about DVDs. This means your 4.7GB DVD really holds about 5.48 GB of raw data.

Now, why is this relevant? Harddrives use their own error correcting schemes too. Manufacturers have the luxury of creating their own encoding systems since they're the ones that provide the read/write mechanisms. You can't pull the platter out of one harddrive and stick it in another. Hard drives typically use CRC (cyclic redundancy check) encoding schemes. I know you have all gotten CRC errors on a floppy way back when - that's what it stands for. Anyway, CRC is much less efficent when you compare the protected data to parity information ratios. While I wasn't able to pull the actual numbers from the Internet or my old math books, you can find a discussion and sample math here.

When you boil it down and relate all this information to our magical harddrive, the maximum usable density of the data would hover between 85%, or 6630 DVDs/in^2, to 60%, a measly 4680 DVDs/in^2, of the listed capacity. This is all assuming that the ideal lab conditions are maintained for a consumer level product.

As always, beware what the numbers tell you. However, if this can fly, then it would be an awesome step forward. Once you get Windows 2010 installed, you might even have a few Gig to play around with!

Most hardware that can access DVDs will not allow you to even read the *encrypted* data unless you unlock it first. I'd imagine that means that you would not be able to copy a DVD without DeCSS.

Err .. no.

If you have a DVD-ROM drive and a DVD movie handy, mount it up and examine the directory structure. DVD movies are stored on the media in UDF (Universal Disk Format) format; you can download the UDF specification from the Optical Storage Technology Association. There is a standard directory structure for all DVD-Video discs. For example, the VIDEO_TS directory contains files that contain pointers to the sectors on the media that contain the actual video streams. There is an AUDIO_TS that does the same for audio. If you're interested in specifics on the filesystem, here's a link with more information.

The point is that none of this structure is an industry secret (it's actually a widely-available standard), and nothing prevents you from reading the video or audio content on the CD. The problem is that you cannot meaningfully use it (read: play it) unless you get around the Content Scrambling System. Again, there is nothing that prevents people from doing a direct content-to-content copy of a DVD-Video disc. CSS is meant to restrict use of the content, not readability.