[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Libcdio-devel] CD-Text patches

From: Thomas Schmitt
Subject: Re: [Libcdio-devel] CD-Text patches
Date: Mon, 28 Nov 2011 17:46:02 +0100


> Since you are a nice guy,

... which compensates for my lack of sysadmin intelligence ... :))

> if you want I'll convert these to text and send it to you privately.

That would be great.

> Folks all this back and forth and digging around and realizing this isn't
> exactly in the right kind information or document format is why someone
> should write better documents for CD Text. And if not us (where this issue
> has been coming up), then by whom?

I roughly know that for CD writing i would announce the Pack data in
the upper two bits of the Data Form byte column of a CD SAO Cue Sheet.

MMC-5 Table 567 says that with value 11b i can thransmit 4 Packs of
data per frame. Footnote 3 talks of "R-W", whereas the next sentence
under that table talks of "P-W" in Lead-in:
  "When this Data Form of Sub-channel is selected, along with 01h
   Data Form of Main Data, this indicates that there is an attempt
   to write Raw P-W Sub-channel data in the Lead-in. Absolute Time
   field should be set with the start address of the Lead-in, [...]"
Main Data Form 01h is a CD-DA frame with no payload data. (MMC-5 Table 562)

MMC-5 Table 555 gives an example of a CUE SHEET. Three rows have Data
Form C0h, which would be Pack Data combined with Main Data Form 0
= CD-DA payload frame.
MMC-5 Figure 128 says that the 96 bytes of Pack Data would be appended
to the CD-DA payload data of the frames.

So my knowledge gap seems to be with the format of Pack Data
... although in the light of my own summary, MMC-3 appendix J might
really fill it now.
But i am still clueless about "R-W" sub channel and "P-W" sub channel.

Maybe i should again study the code in the dungeon dimensions of
libburn, whether there are more hints about sub channel.
And the CD Device Model paragraphs of MMC-1 to MMC-6.
Each skimming yields a bit more of insight.

Still i could need an example CD which is known to deliver CD-Text
to CD music players. Its ingredients and a recipe for cooking it
by a free burn program would help a lot.

Have a nice day :)


reply via email to

[Prev in Thread] Current Thread [Next in Thread]