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authorR. Bernstein <rocky@gnu.org>2012-03-05 05:51:31 -0500
committerR. Bernstein <rocky@gnu.org>2012-03-05 05:51:31 -0500
commit76a3d8016abbcca702c64e16bc19c183f25d4e97 (patch)
tree9a1a9725a98f68f587e729c682176f2243b361ea /doc/cd-text-format.texi
parent09917474d54ff9cc51cd5e4e8e77999f287c32ee (diff)
Minor expository changes
Diffstat (limited to 'doc/cd-text-format.texi')
-rw-r--r--doc/cd-text-format.texi26
1 files changed, 14 insertions, 12 deletions
diff --git a/doc/cd-text-format.texi b/doc/cd-text-format.texi
index c37d4024..67526754 100644
--- a/doc/cd-text-format.texi
+++ b/doc/cd-text-format.texi
@@ -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{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,
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
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
-next section. A shortcut for repeated identical track texts is
-provided, so that a text that is identical to the one of the previous
-track occupies only 2 or 4 bytes.
+next section. Since information such as the Disc and Genre
+Identification is often the same across mutiple tracks, a compact way
+to repeat identical information is provided.
@node 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
zero track value indicates that the information pertains to the whole
-album. Higher numbers are valid for types @kbd{0x80} to @kbd{0x85},
-and @kbd{0x8e}. In these pack types, there should be one text pack for
-the disc and one for each track. With types @kbd{0x88} and
-@kbd{0x89}, the second byte is a track number too. With type
-@kbd{0x8f}, the second byte counts the record parts from 0 to 2.
+album. Higher numbers are valid for track-oriented packs (types
+@kbd{0x80} to @kbd{0x85}, and @kbd{0x8e}). In these pack types, there
+should be one text pack for the disc and one for each track. With TOC
+packs (types @kbd{0x88} and @kbd{0x89}), the second byte is a track
+number too. With type @kbd{0x8f}, the second byte counts the record
+parts from 0 to 2.
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
@kbd{0x8e}) repeats identically for the next track, then it may be
-represented by a TAB character (ASCII 9) for single byte texts,
-resp. two TAB characters for double byte texts. (This should be used
-because 256 * 12 bytes is few space for 99 tracks.)
+represented by a TAB character (ASCII 9) for single byte texts, and
+two TAB characters for double byte texts. This is desirable because
+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
@kbd{0x87} pack of a block. They may or may not be repeated at the start