Rainbow books are the most common CD standards. Have there ever been CDs (or DVDs or Blu-Rays) that use different standards? Maybe Gamecube discs or PSP discs?
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6Did you really mean to include DVDs and Blu-rays? Those aren’t described by the rainbow books, so your question as stated has a rather trivial answer but I imagine it’s not the one you’re looking for.– Stephen KittDec 25, 2022 at 19:41
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2There are various copy-protection schemes which bend the existing "rainbow book" standards. Do those count? After all, they are not "different standards". And I don't think a single CD drive has ever been built that doesn't follow the "rainbow book" standards - what would be the point?– dirktDec 25, 2022 at 19:54
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5Also, perhaps pedantically, a disc which doesn’t follow the standards can’t be called a CD.– Stephen KittDec 25, 2022 at 20:15
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@StephenKitt I thought DVDs and Blu-Rays use the Rainbow Books too. What standards do they use?– zomegaDec 25, 2022 at 20:27
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3@zomega DVDs (and Blue-ray)got their own 'books' which are fully stand alone. Standard DVD format is for example defined as ECMA-267– RaffzahnDec 25, 2022 at 23:47
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4 Answers
The Rainbow Books only define the CD stadards. Any other disc standards defined elsewhere are therefore not CDs and not defined by the Rainbow Books.
So any other disc format, or even a copy protected audio disc, is not a CD because it does not follow the CD standards.
Gamecube discs were MiniDVD-based but incompatible, they used a custom format to avoid paying license fees.
PSP discs were UMDs, not CDs.
DVD and Blu-Ray discs are not CD either. DVD disc standards are governed by DVD Books by DVD Forum. Blu Ray discs have their own standard.
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So there were indeed different standards used on Gamecube and PSP. That's what I wanted to know.– zomegaDec 25, 2022 at 20:44
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3
(This is to be taken as extension to Alan's Answer)
Anything not following the standard is not a CD and can not be read on a CD drive.
What you may be thinking of are different formats.
Only the RED Book describes what a CD is. All other books describe data formats used with a CD.
Disks can well be made to CD standards regarding levels like physical size and orientation, reflection levels, bit timing, track size, etc, but written with different data structures. Either according to some of the other 'books' or some proprietary format. This can be done to store different kind of information or for copy protection.
Such changes may result in those disks not being recognized by firmware and/or drivers of/for standard drives. This can be done with subtle changes like directory structure data or completely different block structure.
This work very much the same way as with standard diskettes diverging from the format IBM had selected for their computers. They are still standard diskettes, that could be read on a standard drive - but to do so on an IBM compatible, one would need specific drivers/access software.
Also, neither DVD nor Blu-ray are CDs. They follow inherently different physical standards. They need different lasers with different power, different colour and different focal point to be read. The fact that drives can be made to adjust to CD, DVD and Blu-ray is due to the way the drives are designed, not due to the standards (*1).
*1 - That is except for the basic physical dimensions - which luckily all opted for at least one variant common to all three types:))
answered Dec 25, 2022 at 23:24
There are some semantics involved.
If the 'CD' does not follow the rainbow book standards then it is strictly speaking not a CD and not eligible for the trade mark logo etc.
There are non standard CD media. The most infamous ones being some of the copy protected CD media disasters (Shakira Laundry Service being a fine example). All the ones I can think of offhand are copy protection schemes - although some copy protection schemes are compliant, particularly on game consoles.
The GD-ROM disks used in the Sega Dreamcast console did not follow CD-ROM standards. The proprietary format developed for Sega by Yamaha packed bits on the disk more tightly than a standard CD-ROM, allowing up to 1GB of data to be stored on the disk.
