Minor expository changes

This commit is contained in:
R. Bernstein
2012-03-05 05:51:31 -05:00
parent 09917474d5
commit 76a3d8016a

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@@ -102,7 +102,7 @@ Additional notes regarding Pack Types:
@item Pack Types @kbd{0x8a} to @kbd{0x8c} although not specified are reserved for potential future use. @item Pack Types @kbd{0x8a} to @kbd{0x8c} although not specified are reserved for potential future use.
@item Pack Types @kbd{0x86}, @kbd{0x87}, @kbd{0x88}, @kbd{0x89}, @kbd{0x8d} (Disc Identification, Genre Identification, Table of Contents, Second Table of Contents and Closed Information respectively) apply to the whole @item Pack Types @kbd{0x86}, @kbd{0x87}, @kbd{0x88}, @kbd{0x89}, @kbd{0x8d} (Disc Identification, Genre Identification, Table of Contents, Second Table of Contents and Closed Information respectively) apply to the whole
disc, and can not be attached to individual tracks. disc, and cannot be attached to individual tracks.
@item Pack Types @kbd{0x80}, @kbd{0x81}, @kbd{0x82}, @kbd{0x83}, @kbd{0x84}, @kbd{0x85}, and @kbd{0x8e} (Performers, Songwriters, Composers, @item Pack Types @kbd{0x80}, @kbd{0x81}, @kbd{0x82}, @kbd{0x83}, @kbd{0x84}, @kbd{0x85}, and @kbd{0x8e} (Performers, Songwriters, Composers,
Arrangers, and Message Area respectively) have to be attributed to Arrangers, and Message Area respectively) have to be attributed to
@@ -113,9 +113,9 @@ each track if they are present for the whole disc.
The total size of a block's attribute set is restricted by the fact The total size of a block's attribute set is restricted by the fact
that it has to be stored in at most 253 records with 12 bytes of that it has to be stored in at most 253 records with 12 bytes of
payload. These records are called @emph{Text Packs} described in the payload. These records are called @emph{Text Packs} described in the
next section. A shortcut for repeated identical track texts is next section. Since information such as the Disc and Genre
provided, so that a text that is identical to the one of the previous Identification is often the same across mutiple tracks, a compact way
track occupies only 2 or 4 bytes. to repeat identical information is provided.
@node Pack Contents @node Pack Contents
@section Pack Contents @section Pack Contents
@@ -141,11 +141,12 @@ The first byte of each pack contains the pack type. See
The second byte often gives the track number of the pack. However, a The second byte often gives the track number of the pack. However, a
zero track value indicates that the information pertains to the whole zero track value indicates that the information pertains to the whole
album. Higher numbers are valid for types @kbd{0x80} to @kbd{0x85}, album. Higher numbers are valid for track-oriented packs (types
and @kbd{0x8e}. In these pack types, there should be one text pack for @kbd{0x80} to @kbd{0x85}, and @kbd{0x8e}). In these pack types, there
the disc and one for each track. With types @kbd{0x88} and should be one text pack for the disc and one for each track. With TOC
@kbd{0x89}, the second byte is a track number too. With type packs (types @kbd{0x88} and @kbd{0x89}), the second byte is a track
@kbd{0x8f}, the second byte counts the record parts from 0 to 2. number too. With type @kbd{0x8f}, the second byte counts the record
parts from 0 to 2.
The third byte is a sequential counter. The third byte is a sequential counter.
@@ -186,9 +187,10 @@ at most 2048 text packs possible.
If a text of a track (pack types @kbd{0x80} to @kbd{0x85} and If a text of a track (pack types @kbd{0x80} to @kbd{0x85} and
@kbd{0x8e}) repeats identically for the next track, then it may be @kbd{0x8e}) repeats identically for the next track, then it may be
represented by a TAB character (ASCII 9) for single byte texts, represented by a TAB character (ASCII 9) for single byte texts, and
resp. two TAB characters for double byte texts. (This should be used two TAB characters for double byte texts. This is desirable because
because 256 * 12 bytes is few space for 99 tracks.) there is a somewhat limited amount of space for CD Text --- 256 * 12
bytes which may have to accomodate up to 99 tracks.
The two binary bytes of pack type @kbd{0x87} are written to the first The two binary bytes of pack type @kbd{0x87} are written to the first
@kbd{0x87} pack of a block. They may or may not be repeated at the start @kbd{0x87} pack of a block. They may or may not be repeated at the start