claunia/libcdio-osx
Archived
1
0
Fork 0
Code Issues 2 Pull Requests Actions Packages Projects Releases Wiki Activity

First feeble attempt at documentation.

Browse Source
This commit is contained in:
rocky
2003-07-28 02:25:37 +00:00
parent c7703d2fd1
commit 621f7e99ad
4 changed files with 320 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
Makefile.am
View File

@@ -1,4 +1,4 @@
# $Id: Makefile.am,v 1.8 2003/04/25 21:28:39 rocky Exp $
# $Id: Makefile.am,v 1.9 2003/07/28 02:25:37 rocky Exp $
#
# Copyright (C) 2003 Rocky Bernstein <rocky@panix.com>
#
@@ -22,8 +22,7 @@
EXTRA_DIST = libpopt.m4 THANKS libcdio.spec.in
# SUBDIRS = doc include lib src test
SUBDIRS = include lib src test
SUBDIRS = doc include lib src test
# pkg-config(1) related rules
pkgconfigdir = $(libdir)/pkgconfig

5
configure.ac
View File

@@ -15,10 +15,10 @@ dnl along with this program; if not, write to the Free Software
dnl Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
dnl 02111-1307, USA.
AC_REVISION([$Id: configure.ac,v 1.29 2003/06/13 04:47:20 rocky Exp $])dnl
AC_REVISION([$Id: configure.ac,v 1.30 2003/07/28 02:25:37 rocky Exp $])dnl
AC_INIT(lib/cdio.c)
AM_CONFIG_HEADER(config.h)
AM_INIT_AUTOMAKE(libcdio, 0.61)
AM_INIT_AUTOMAKE(libcdio, 0.62)
AM_SANITY_CHECK
@@ -292,6 +292,7 @@ AC_OUTPUT([ \
include/Makefile \
include/cdio/Makefile \
include/cdio/version.h \
doc/Makefile \
lib/Makefile \
src/Makefile \
test/check_nrg.sh \

17
doc/Makefile.am Normal file
View File

@@ -0,0 +1,17 @@
libcdio_TEXINFOS = libcdio.texi
%.ps.gz: %.ps
gzip -9c $< > $@
.texi.pdf:
texi2pdf $<
.texi.html:
texi2html $<
.texi.txt:
makeinfo --no-headers $< > $@
all-formats: libcdio.pdf libcdio.dvi libcdio.txt libcdio.ps libcdio.html
MOSTLYCLEANFILES = libcdio.html libcdio.pdf libcdio.ps.gz

298
doc/libcdio.texi Normal file
View File

@@ -0,0 +1,298 @@
\input texinfo @c -*-texinfo-*-
@paragraphindent 0
@exampleindent 0
@c %**start of header
@setfilename libcdio.info
@set libcdio @code{libcdio}
@settitle The GNU libcdio library
@setchapternewpage on
@ifinfo
This file documents GNU CD input and control library
Copyright (C) Herbert Valerio Riedel @email{<hvr@@gnu.org>} and Rocky
Bernstein @email{<rocky@@panix.com>}
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with the
Invariant Sections being ``Free Software'' and ``Free Software Needs
Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.
(a) The Free Software Foundation's Back-Cover Text is: ``You have
freedom to copy and modify this GNU Manual, like GNU software. Copies
published by the Free Software Foundation raise funds for GNU
development.''
@end ifinfo
@titlepage
@title GNU libcdio library
@subtitle $Id: libcdio.texi,v 1.1 2003/07/28 02:25:37 rocky Exp $
@author Rocky Bernstein et al.
@page
@vskip 0pt plus 1filll
Copyright @copyright{} 2003 Herbert Valerio Riedel
@email{<hvr@@gnu.org>} and Rocky Bernstein @email{<rocky@@panix.com>}
@sp 1
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with the
Invariant Sections being ``Free Software'' and ``Free Software Needs
Free Documentation'', with the Front-Cover Texts being ``A GNU Manual,''
and with the Back-Cover Texts as in (a) below.
(a) The Free Software Foundation's Back-Cover Text is: ``You have
freedom to copy and modify this GNU Manual, like GNU software. Copies
published by the Free Software Foundation raise funds for GNU
development.''
@end titlepage
@page
@ifnottex
@node Top, History, (dir), (dir)
@top The GNU Video CD Ripping Program (@value{program})
This file documents GNU CD input and control library
Copyright (C) 2003 Herbert Valerio Riedel and Rocky Bernstein
@menu
* History:: How this came about
* Purpose:: Why this library?
* CD Formats:: A tour through the CD-specification spectrum
* How to use:: Okay enough babble, lemme at the library!
Indices
* General Index:: Overall index
@end menu
@end ifnottex
@contents
@node History
@chapter History
As a result of the repressive Digital Millenium Copyright Act (DMCA)
I became aware of Video CD's (VCD's). Video CD's are not subject to
the DMCA and therefore enjoy the protection afforded by copyright but
no more. But in order for VCD's to be competitive with DVD's, good
tools (including GPL tools) are needed for authoring and playing
them. And so through VCD's I became aware of the excellent Video CD
tools by Herbert Valerio Riedel which form the @kbd{vcdimager} package.
Although vcdimager is great for authoring, examining and extracting
parts of a Video CD, it is not a VCD player. And when I looked at the
state of Video CD handling in existing VCD players: @code{xine},
@code{MPlayer}, and @code{vlc}, I was a bit disappointed. None handled
playback control, menu selections, or playing still frames and
segments from track 1.
Version 0.7.12 of vcdimager was very impressive, however it lacked
exportable libraries that could be used in other projects. So with the
blessing and encouragement of Herbert Valerio Riedel, I took to
extract and create libraries from this code base. The result was two
libraries: one to extract information from a VCD which I called
libvcdinfo, and another to do the reading and control of a VCD. Well,
actually, at this point I should say that a Video CD is really just
Video put on a existing well-established Compact Disc or CD format. So
the library for this is called @value{libcdio} rather than
@kbd{libvcdio}.
While on the topic of the name @value{libcdio}, I should also explain that
the library really doesn't handle writing or output (the final "o" in
the name). However it was felt that if I put libcdi that might be
confused with a particular CD format called CD-I.
@node Purpose
@chapter The problem and previous work
If around the year 2002 you were to look at the code for a number of
open-source CD or media players that work on several platforms such as
vlc, MPlayer, xine, or xmms to name but a few, you'd find the code to
read a CD sprinked with conditional compilation for this or that
platform.
One CD player, @kbd{xmcd} by Ti Kan, was I think a bit better than
most in that it tried to @emph{encapsulate} the kinds of CD control
mechanisms (SCSI, Linux ioctl, Toshiba, etc.) in a "CD Audio Device
Interface Library" called libdi. However this library is for Audio
CD's only and I don't believe this library has been used outside of
xmcd.
Another project, Simple DirectMedia Layer also encapsulates CD
reading.
@quotation
SDL is a library that allows you portable low-level access to a video
framebuffer, audio output, mouse, and keyboard. With SDL, it is easy
to write portable games which run on ...
@end quotation
Many of the media players mentioned above do in fact can make use of
the SDL library but for @emph{video} output only. Because the encapsulation
is over @emph{many} kinds of I/O (video, joysticks, mice, as well as CD's),
I believe that the level of control provided for CD a little bit
limited. (However to be fair, it may have only been intended for games
and may be suitable for that). Applications that just want the CD
reading and control portion I think will find quite a bit overhead.
At the OS level there is the "A Linux CD-ROM Standard" by David van
Leeuwen from around 1999. This defines a set of definitions and
ioctl's that mask hardware differences of various Compact Disc
hardware. It is a great idea and no doubt something similar exists on
other platforms. However this "standard" lacked adoption on OS's other
than GNU/Linux.
The library ``The Compact Disc Input and Control Library'' encapsulates
CD-ROM reading and control. Applications wishing to be oblivious of
the OS- and device-dependent properties of a CD-ROM can use this
library. 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.
A sample utility for displaying CD info is included.
@node CD Formats
@chapter CD Formats
Much of what I write in this section can be found elsewhere. See for
example @url{http://www.pctechguide.com/08cd-rom.htm} or
@url{http://www.pcguide.com/ref/cd/format.htm}
We give just enough background here to cover Compact Discs and Compact
Disc formats that are handled by this library.
The Sony and Philips Corporations invented and Compact Disc (CD) in
the early 1980s. The specifications for the layout is often referred
to by the color of the cover on the specification.
@menu
* Red Book:: Red Book (CD-DA)
* Yellow Book:: Yellow Book (CD-ROM Digital Data)
* White Book:: White Book (Video CD)
@end menu
@node Red Book
@section Red Book
The first type of CD that was produced was the Compact Disc
Digital Audio (CD-DA) or just plain "audio CD". The specification for
that is covered in what is called the Red Book. Music CD's are
recorded in this format which basically allows for around 74 minutes
of audio per disc and for that information to be split up into
tracks. Tracks are broken up into "sectors" and each sector contains
2,352 bytes. To play one 44.1 kHz CD-DA sampled audio second, 75
sectors are used.
In @value{libcdio} when you you want to read an audio sector, you call the
routine @code{cdio_read_audio_sector()}.
@node Yellow Book
@section Yellow Book
The CD-ROM specification or "Yellow Book" followed a few years later
and describes the extension of CD's to store computer data,
i.e. CD-ROM (Compact Disk Read Only Memory).
The Yellow book CD standard defines two modes:
@subsection Mode1
Mode 1 is the data storage mode used by to store computer
data. The data is laid out in basically the same way as in and audio
CD format, except that the 2,352 bytes of data in each block are
broken down further. 2,048 of these bytes are for "real" data. The
other 304 bytes are used for an additional level of error detecting
and correcting code. This is necessary because data CDs cannot
tolerate the loss of a handful of bits now and then, the way audio
CDs can.
@subsection Mode2
Mode 2 data CDs are the same as mode 1 CDs except that the error
detecting and correcting codes are omitted. This is similar to audio
CDs, i.e. the mode 2 format provides a more flexible vehicle for
storing types of data that do not require high data integrity: for
example, graphics and video can use this format. But in contrast to
the Red book standard, different modes can be mixed together; this is
the basis for the extensions to the original data CD standards known
as CD-ROM Extended Architecture, or CD-ROM XA. CD-ROM XA formats
currently in use are CD-I Bridge formats, Photo CD and VideoCD plus
Sony's Playstation.
@subsection ISO-9660
The Yellow Book does not actually specify how data is to be stored on
or retrieved from a CD-ROM. It was feared that many different
companies would implement proprietary data storage formats using this
specification, resulting in many different incompatible data CDs. To
try to prevent this, representatives of major manufacturers met at the
High Sierra Hotel and Casino in Lake Tahoe, NV, in 1985, to come
together on a common standard for data CDs. This format was nicknamed
High Sierra Format. It was later modified slightly and adopted as ISO
standard 9660. ISO 9660 consists of several "levels":
Level 1 ISO 9660 defines names in the 8+3 convention so familiar to
MS-DOS: eight characters for the filename, a period, and
then three characters for the file type, all in upper case. The
allowed characters are A-Z, 0-9, ".", and "_".Level 1 ISO 9660
requires that files occupy a contiguous range of sectors. This allows
a file to be specified with a start block and a count. The maximum
directory depth is 8.
Level 2 ISO 9660 allows far more flexibility in filenames, but isn't
usable on some systems, notably MS-DOS.
Level 3 ISO-9660 allows non-contiguous files, useful if the file was
written in multiple packets with packet-writing software.
There have been a number of extensions to the ISO 9660 CD-ROM file
format. One extension is Microsoft's Joliet specification, designed to
resolve a number of deficiencies in the original ISO 9660 Level 1 file
system, and in particular to support the long file names used in
Windows 95 and subsequent versions of Windows.
Another extension is the Rock Ridge Interchange Protocol (RRIP), which
enables the recording of sufficient information to support POSIX File
System semantics.
@node White Book
@section White Book
The White Book, finalized in 1993, defines the VideoCD specification
The White Book is also known as Digital Video (DV). A VideoCD disc
contains one data track recorded in CD-ROM XA Mode 2 Form 2. It is
always the first track on the disc (Track 1). The ISO 9660 file
structure and a CD-i application program are recorded in this track,
as well as the VideoCD Information Area which gives general
information about the VideoCD disc. After the data track, video is
written in one or more subsequent tracks within the same
session. These tracks are also recorded in Mode 2 Form 2.
In @value{libcdio} when you you want to read a mode2 format 2 audio
sector you call the routine @code{cdio_read_mode2_sector()}.
@node How to use
@chapter How to use
@node General Index
@unnumbered General Index
@printindex cp
@tex
% I think something like @colophon should be in texinfo. In the
% meantime:
\long\def\colophon{\hbox to0pt{}\vfill
\centerline{The body of this manual is set in}
\centerline{\fontname\tenrm,}
\centerline{with headings in {\bf\fontname\tenbf}}
\centerline{and examples in {\tt\fontname\tentt}.}
\centerline{{\it\fontname\tenit\/},}
\centerline{{\bf\fontname\tenbf}, and}
\centerline{{\sl\fontname\tensl\/}}
\centerline{are used for emphasis.}\vfill}
\page\colophon
% Blame: doc@cygnus.com, 1991.
@end tex
@bye