
HOW TO CREATE A SINGLE-SESSION "CD PLUS" TYPE DISC
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A "CD Plus" disc (also known as "CD Extra"), is a disc that contains
both data and audio tracks. It is similar to a mixed-mode disc except
that the data track is hidden in such a way that a normal audio CD
player will not see it, but a computer CDROM drive will. The new
"CD Plus" standard specifies that these type of discs be written in
multiple sessions (with audio in the first session and data in the
second), but there is an easier way to make this type of disc in a
single session. This method is very popular and continues to be
used by the CDROM industry.

WARNING: Some CD recorders will not allow you to make this type of
disc because they restrict the length of the first track's pregap
to three seconds in length. Also, some CDROM drives will not properly
read these discs.

The "trick" is to hide the data track in the pregap (INDEX 0) of the
first audio track so that a normal audio CD player will not see it,
but a computer CDROM drive will.

STEP 1 - Create an ISO9660 image of the data that you wish to hide.
         You can use MAKEISO.EXE or any Windows based ISO9660 image 
         builder.

STEP 2 - Convert the ISO9660 image file to RAW sector format using
         the ISO2RAW.EXE utility. You *must* use both the /POSTGAP
         and /SCRAMBLE options!

STEP 3 - Get a directory listing of the RAW data file and divide the
         file's length by 2352 to determine the number of frames the
         data will occupy on the disc (if you didn't get a whole number,
         then you did something wrong). Convert this number to minutes,
         seconds, and frames (at 75 frames per second).

STEP 4 - This is where it gets a little tricky... Since you are
         writing the data into the pregap of the first audio track,
         you have to fool everything into thinking that the data is
         really audio. This means that you must attach the raw data
         onto the beginning of the first audio file. Presently, there
         is no utility to do this, so you're on your own. If the first
         audio track is in a WAV file, then you will have to figure
         out how to attach the raw data and properly update the WAV
         file header fields. If your audio data is in a straight
         binary file, then this task is a little easier because you
         don't have to deal with updating the WAV file header.

STEP 5 - Write the CUE SHEET (this is just an example)...

         FILE TRACK1.WAV AUDIO 2352
           TRACK 01
           INDEX 00 00:00:00       (data track is hidden here)
           INDEX 01 MM:SS:FF       (numbers calculated in Step 3).
         FILE TRACK2.WAV AUDIO 2352
           TRACK 02
           INDEX 00 00:00:00
         FILE TRACK3.WAV AUDIO 2352
           TRACK 03
           INDEX 00 00:00:00

STEP 6 - Use DAO.EXE to record the new disc. If you are using binary
         audio files instead of WAV files, then make sure that you
         use the /BIN option.

