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Refer to libcdio constants more. Note OSX and FreeBSD drivers. Note

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there is a maximum LSN/LBA/MSF value.
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rocky
2004-06-06 11:51:40 +00:00
parent 880ed2da3a
commit ccd1f5c29c
1 changed files with 77 additions and 31 deletions
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doc/libcdio.texi
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@@ -46,7 +46,7 @@ development.''
@titlepage
@title GNU libcdio library
@subtitle $Id: libcdio.texi,v 1.22 2004/04/30 06:54:15 rocky Exp $
@subtitle $Id: libcdio.texi,v 1.23 2004/06/06 11:51:40 rocky Exp $
@author Rocky Bernstein et al.
@page
@@ -200,9 +200,10 @@ device-dependent properties of a CD-ROM can use this library.
Also included is a library, @command{libiso9660}, for working with ISO-9660
filesystems.
Some support for disk image types like BIN/CUE and NRG is
available, so applications that use this library also have the ability
to read disc images as though they were CDs.
Some support for disk-image types like cdrdao's TOC, CDRWIN's BIN/CUE
and Ahead Nero's NRG format is available, so applications that use this
library also have the ability to read disc images as though they were
CDs.
Immediate of the library in this package are the Video CD authoring
and ripping tools, VCDImager (@url{http://vcdimager.org}), a
@@ -221,11 +222,26 @@ information. The command @command{cd-drive} shows what drivers are
available and some basic properties of cd-drives attached to the
system. (But media may have to be inserted in order to get this info.)
Other utility programs in the libcdio package are @command{cd-read},
for performing low-level block reading of a CD or CD image,
@command{iso-info} for displaying ISO-9660 information from an
ISO-9660 image, and @command{iso-read} for extracting files from an
ISO-9660 image.
Other utility programs in the libcdio package are:
@table @code
@item @code{cd-drive}
lists out drive capabilities
@item cd-read
performs low-level block reading of a CD or CD image,
@item @code{iso-info}
displays ISO-9660 information from an ISO-9660 image
@item @code{iso-read}
extracts files from an ISO-9660 image.
@end table
At present, there is no support for directing CD Audio control,
e.g. playing, stopping, or pausing of a CD-CA where the blocks are not
@@ -416,7 +432,8 @@ In this section we describe CD properties and terms that we make use
of in @value{libcdio}.
A CD is formated into a number of @term{tracks}, and a CD can hold at
most 99 such tracks. Between the tracks CD specifications require a
most 99 such tracks. This is defined by @code{CDIO_CD_MAX_TRACKS} in
@file{cdio/sector.h}. Between the tracks CD specifications require a
``2 second'' in gap (called a @term{lead-in gap}. This is unused space
with no ``data'' similar to the space between tracks on an old
phonograph. The word ``second'' here really refers to a measure of
@@ -444,7 +461,12 @@ largest legal track position. In @value{libcdio},
@section block addressing (MSF, LSN, LBA)
A track is broken up into a number of 2352-byte @emph{blocks} which we
sometimes call @emph{sectors}. Whereas tracks have to have a gap
between them, a block or sector does not.
between them, a block or sector does not. (In @value{libcdio} the
block size constant is defined using @code{CDIO_CD_FRAMESIZE_RAW}).
A Compact Disc has a limit on the number of blocks or sectors. This
values is defined by constant @code{CDIO_CD_MAX_LSN} in
@file{cdio/sector.h}.
One can addressing a block in one of three formats. The oldest format
is by it's minute/second/frame number, also referred to as @term{MSF}
@@ -452,19 +474,21 @@ and written in time-like format MM:SS:FF (e.g. 30:01:40). In this
notation there are 75 ``frames'' in a ``second,'' and the familiar (if
awkward) 60 seconds in a minute. @emph{Frame} here is what we called a
@emph{block} above. The CD specification defines ``frame'' to be
@emph{another} unit which makes up a block. Very confusing.
@emph{another} unit which makes up a block. Very confusing. A frame is
also sometimes called a sector, analogous to hard-disk terminalogy.
Even more confusing is is using this time-like notation for an address
or for a length. Too often people confuse the MSF notation this with
an amount of time. A ``second'' (or 75 blocks) in this notation is
only a second of playing time for something encoded as CD-DA. It does
@emph{not} necessarily represent the amount time that it will take to
play a of Video CD---usually you need more blocks than this. Nor does
it represent the amount of data used to play a second of an
MP3---usually you need fewer blocks than this. It is also not the
amount of time your CD-ROM will take to read a ``second'' of data off
a Compact Disc: for example a 12x CD player will read 12x75 2352-byte
blocks in a one second of time.
Even more confusing is using this time-like notation for an address or
for a length. Too often people confuse the MSF notation this with an
amount of time. A ``second'' (or @code{CDIO_CD_FRAMES_PER_SEC} blocks)
in this notation is only a second of playing time for something
encoded as CD-DA. It does @emph{not} necessarily represent the amount
time that it will take to play a of Video CD---usually you need more
blocks than this. Nor does it represent the amount of data used to
play a second of an MP3---usually you need fewer blocks than this. It
is also not the amount of time your CD-ROM will take to read a
``second'' of data off a Compact Disc: for example a 12x CD player
will read 12x @code{CDIO_CD_FRAMES_PER_SEC}
@code{CDIO_CD_FRAMSIZE_RAW}-byte blocks in a one second of time.
Furthermore when programming, it is generally more cumbersome to use
an MSF rather than a LBA or LSN described below, since subtraction of
@@ -472,12 +496,14 @@ two MSF's has the awkwardness akin to subtraction using Roman
Numerals.
Probably the simplest way to address a block is to use its @term{LSN}
or ``logical sector number.'' This just numbers the blocks from 0
on. The Lead-in and Lead-out gaps described above have LSNs just like
any other space on a CD. The last unit of address is a @term{LBA}. It
is the same as a LSN but the 150 blocks assocated with the initial
or ``logical sector number.'' This just numbers the blocks usually
from 0 on. @emph{fix me: LSNs can be negative up to the pregap size?}
The Lead-in and Lead-out gaps described above have LSNs just like any
other space on a CD. The last unit of address is a @term{LBA}. It is
the same as a LSN but the 150 blocks assocated with the initial
lead-in is are not counted. So to convert a LBA into an LSN you just
add 150. Why the distinction between LBA and LSN? I don't know.
add 150. Why the distinction between LBA and LSN? I don't know,
perhaps this has something to do with ``multisession'' CDs.
@node How to use
@chapter How to use
@@ -914,12 +940,19 @@ main(int argc, const char *argv[])
@chapter Diagnostic programs (@samp{cd-info}, @samp{cd-read}, @samp{iso-info}, @samp{iso-read})
@menu
* cd-drive:: list out CD-ROM drive information
* cd-info:: list out CD or CD-image information
* cd-read:: read blocks of a CD or CD image
* iso-info:: list out ISO-9600 image information
* iso-read:: extract a file from an ISO 9660 image
@end menu
@node cd-drive
@section @samp{cd-drive}
@samp{cd-drive} lists out drive information and information about
what hardware drivers are available.
@node cd-info
@section @samp{cd-info}
@@ -955,6 +988,8 @@ image.
* GNU/Linux::
* Microsoft::
* Solaris::
* FreeBSD::
* OS X::
@end menu
@node GNU/Linux
@@ -988,6 +1023,20 @@ interface, and has taken steps to make using ASPI more inaccessible
There are two CD drive access methods on Solaris:
ATAPI and SCSI. SCSI is preferred when possible.
@node FreeBSD
@section FreeBSD
There are two CD drive access methods on Solaris:
ioctl and CAM (common access method). CAM is preferred when possible;
it is however sort of a hybrid and includes some ioctl code.
More work on this driver is needed. Volunteers?
@node OS X
@section OS X
More work on this driver is needed. Volunteers?
@node ISO-9660 Character Sets
@appendix ISO-9660 Character Sets
@@ -1069,9 +1118,6 @@ and sub-channel information. It is a simple text file, use your
favorite text editor to create it.
@end quotation
We don't support this image format currently, but intend to in the
future. Anyone want to volunteer?
@node BIN/CUE Format
@appendixsec BIN/CUE Format
@cindex BIN/CUE, CD Image Format