mirror of https://github.com/python/cpython
New documentation on the CD module.
This commit is contained in:
parent
3caad8c291
commit
ffd6de1049
|
@ -100,6 +100,7 @@ ref.dvi: ref.tex ref1.tex ref2.tex ref3.tex ref4.tex ref5.tex ref6.tex \
|
|||
LIBFILES = lib.tex \
|
||||
libal.tex libaifc.tex libamoeba.tex libarray.tex libaudio.tex libaudioop.tex \
|
||||
libbltin.tex \
|
||||
libcd.tex \
|
||||
libcgi.tex libcopy.tex libctb.tex libcrypto.tex \
|
||||
libdbm.tex \
|
||||
libexcs.tex \
|
||||
|
|
|
@ -135,6 +135,7 @@ language.
|
|||
\input{libsgi} % SGI IRIX ONLY
|
||||
\input{libal}
|
||||
%\input{libaudio}
|
||||
\input{libcd}
|
||||
\input{libfl}
|
||||
\input{libfm}
|
||||
\input{libgl}
|
||||
|
|
|
@ -135,6 +135,7 @@ language.
|
|||
\input{libsgi} % SGI IRIX ONLY
|
||||
\input{libal}
|
||||
%\input{libaudio}
|
||||
\input{libcd}
|
||||
\input{libfl}
|
||||
\input{libfm}
|
||||
\input{libgl}
|
||||
|
|
|
@ -0,0 +1,288 @@
|
|||
\section{Built-in Module \sectcode{cd}}
|
||||
\bimodindex{cd}
|
||||
|
||||
This module provides an interface to the Silicon Graphics CD library.
|
||||
It is available only on Silicon Graphics systems.
|
||||
|
||||
The way the library works is as follows. A program opens the CD-ROM
|
||||
device with \code{cd.open()} and creates a parser to parse the data
|
||||
from the CD with \code{cd.createparser()}. The object returned by
|
||||
\code{cd.open()} can be used to read data from the CD, but also to get
|
||||
status information for the CD-ROM device, and to get information about
|
||||
the CD, such as the table of contents. Data from the CD is passed to
|
||||
the parser, which parses the frames, and calls any callback
|
||||
functions that have previously been added.
|
||||
|
||||
An audio CD is divided into \dfn{tracks} or \dfn{programs} (the terms
|
||||
are used interchangeably). Tracks can be subdivided into
|
||||
\dfn{indices}. An audio CD contains a \dfn{table of contents} which
|
||||
gives the starts of the tracks on the CD. Index 0 is usually the
|
||||
pause before the start of a track. The start of the track as given by
|
||||
the table of contents is normally the start of index 1.
|
||||
|
||||
Positions on a CD can be represented in two ways. Either a frame
|
||||
number or a tuple of three values, minutes, seconds and frames. Most
|
||||
functions use the latter representation. Positions can be both
|
||||
relative to the beginning of the CD, and to the beginning of the
|
||||
track.
|
||||
|
||||
Module \code{cd} defines the following functions:
|
||||
|
||||
\renewcommand{\indexsubitem}{(in module cd)}
|
||||
\begin{funcdesc}{createparser}{}
|
||||
Create and return an opaque parser object. The methods of the parser
|
||||
object are described below.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{msftoframe}{min\, sec\, frame}
|
||||
Converts a \code{(minutes, seconds, frames)} triple representing time
|
||||
in absolute time code into the corresponding CD frame number.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{open}{\optional{device\optional{\, mode}}}
|
||||
Open the CD-ROM device. The return value is an opaque player object;
|
||||
methods of the player object are described below. The device is the
|
||||
name of the SCSI device file, e.g. /dev/scsi/sc0d4l0, or \code{None}.
|
||||
If omited or \code{None}, the hardware inventory is consulted to
|
||||
locate a CD-ROM drive. The \code{mode}, if not omited, should be the
|
||||
string 'r'.
|
||||
\end{funcdesc}
|
||||
|
||||
The module defines the following variables:
|
||||
|
||||
\begin{datadesc}{error}
|
||||
Exception raised on various errors.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{DATASIZE}
|
||||
The size of one frame's worth of audio data. This is the size of the
|
||||
audio data as passed to the callback of type \code{audio}.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{BLOCKSIZE}
|
||||
The size of one uninterpreted frame of audio data.
|
||||
\end{datadesc}
|
||||
|
||||
The following variables are states as returned by \code{getstatus}:
|
||||
|
||||
\begin{datadesc}{READY}
|
||||
The drive is ready for operation loaded with an audio CD.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{NODISC}
|
||||
The drive does not have a CD loaded.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{CDROM}
|
||||
The drive is loaded with a CD-ROM. Subsequent play or read operations
|
||||
will return I/O errors.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{ERROR}
|
||||
An error aoocurred while trying to read the disc or its table of
|
||||
contents.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{PLAYING}
|
||||
The drive is in CD player mode playing an audio CD through its audio
|
||||
jacks.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{PAUSED}
|
||||
The drive is in CD layer mode with play paused.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{STILL}
|
||||
The equivalent of \code{PAUSED} on older (non 3301) model Toshiba
|
||||
CD-ROM drives. Such drives have never been shipped by SGI.
|
||||
\end{datadesc}
|
||||
|
||||
Player objects (returned by \code{cd.open()}) have the following
|
||||
methods:
|
||||
|
||||
\renewcommand{\indexsubitem}{(CD player object method)}
|
||||
\begin{funcdesc}{allowremoval}{}
|
||||
Unlocks the eject button on the CD-ROM drive permitting the user to
|
||||
eject the caddy if desired.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{bestreadsize}{}
|
||||
Returns the best value to use for the \code{num_frames} parameter of
|
||||
the \code{readda} method. Best is defined as the value that permits a
|
||||
continuous flow of data from the CD-ROM drive.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{close}{}
|
||||
Frees the resources associated with the player object. After calling
|
||||
\code{close}, the methods of the object should no longer be used.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{eject}{}
|
||||
Ejects the caddy from the CD-ROM drive.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{getstatus}{}
|
||||
Returns information pertaining to the current state of the CD-ROM
|
||||
drive. The returned information is a tuple with the following values:
|
||||
\code{state}, \code{track}, \code{rtime}, \code{atime}, \code{ttime},
|
||||
\code{first}, \code{last}, \code{scsi_audio}, \code{cur_block}.
|
||||
\code{rtime} is the time relative to the start of the current track;
|
||||
\code{atime} is the time relative to the beginning of the disc;
|
||||
\code{ttime} is the total time on the disc. For more information on
|
||||
the meaning of the values, see the manual for CDgetstatus.
|
||||
The value of \code{state} is one of the following: \code{cd.ERROR},
|
||||
\code{cd.NODISC}, \code{cd.READY}, \code{cd.PLAYING},
|
||||
\code{cd.PAUSED}, \code{cd.STILL}, or \code{cd.CDROM}.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{gettrackinfo}{track}
|
||||
Returns information about the specified track. The returned
|
||||
information is a tuple consisting of two elements, the start time of
|
||||
the track and the duration of the track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{msftoblock}{min\, sec\, frame}
|
||||
Converts a minutes, seconds, frames triple representing a time in
|
||||
absolute time code into the corresponding logical block number for the
|
||||
given CD-ROM drive. You should use \code{cd.msftoframe()} rather than
|
||||
\code{msftoblock()} for comparing times. The logical block number
|
||||
differs from the frame number by an offset required by certain CD-ROM
|
||||
drives.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{play}{start\, play}
|
||||
Starts playback of an audio CD in the CD-ROM drive at the specified
|
||||
track. The audio output appears on the CD-ROM drive's headphone and
|
||||
audio jacks (if fitted). Play stops at the end of the disc.
|
||||
\code{start} is the number of the track at which to start playing the
|
||||
CD; if \code{play} is 0, the CD will be set to an initial paused
|
||||
state. The method \code{togglepause()} can then be used to commence
|
||||
play.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playabs}{min\, sec\, frame\, play}
|
||||
Like \code{play()}, except that the start is given in minutes,
|
||||
seconds, frames instead of a track number.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playtrack}{start\, play}
|
||||
Like \code{play()}, except that playing stops at the end of the track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playtrackabs}{track\, min\, sec\, frame\, play}
|
||||
Like \code{play()}, except that playing begins at the spcified
|
||||
absolute time and ends at the end of the specified track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{preventremoval}{}
|
||||
Locks the eject button on the CD-ROM drive thus preventing the user
|
||||
from arbitrarily ejecting the caddy.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{readda}{num_frames}
|
||||
Reads the specified number of frames from an audio CD mounted in the
|
||||
CD-ROM drive. The return value is a string representing the audio
|
||||
frames. This string can be passed unaltered to the \code{parseframe}
|
||||
method of the parser object.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seek}{min\, sec\, frame}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to an absolute
|
||||
time code location specified in minutes, seconds, and frames. The
|
||||
return value is the logical block number to which the pointer has been
|
||||
set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seekblock}{block}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to the specified
|
||||
logical block number. The return value is the logical block number to
|
||||
which the pointer has been set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seektrack}{track}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to the specified
|
||||
track. The return value is the logical block number to which the
|
||||
pointer has been set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{stop}{}
|
||||
Stops the current playing operation.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{togglepause}{}
|
||||
Pauses the CD if it is playing, and makes it play if it is paused.
|
||||
\end{funcdesc}
|
||||
|
||||
Parser objects (returned by \code{cd.createparser()}) have the
|
||||
following methods:
|
||||
|
||||
\begin{funcdesc}{addcallback}{type\, func\, arg}
|
||||
Adds a callback for the parser. The parser has callbacks for eight
|
||||
different types of data in the digital audio data stream. The
|
||||
callback is called as follows \code{func(arg, type, data)}.
|
||||
\code{arg} is the user supplied argument, \code{type} is the
|
||||
particular type of callback, and \code{data} is the data returned for
|
||||
this \code{type} of callback. The type of the data depends on the
|
||||
\code{type} of callback as follows.
|
||||
\begin{datadesc}{audio}
|
||||
The argument is a string which can be passed unmodified to
|
||||
\code{al.writesamps}
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{pnum}
|
||||
The argument is an integer giving the program (track) number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{index}
|
||||
The argument is an integer giving the index number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{ptime}
|
||||
The argument is a tuple consisting of the program time in minutes,
|
||||
seconds, and frames.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{atime}
|
||||
The argument is a tuple consisting of the absolute time in minutes,
|
||||
seconds, and frames.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{catalog}
|
||||
The argument is a string of 13 characters, giving the catalog number
|
||||
of the CD.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{ident}
|
||||
The argument is a string of 12 characters, giving the ISRC
|
||||
identification number of the recording. The string consists of two
|
||||
characters country code, three characters owner code, two characters
|
||||
giving the year, and five characters giving a serial number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{control}
|
||||
The argument is an integer giving the control bits from the CD subcode
|
||||
data.
|
||||
\end{datadesc}
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{deleteparser}{}
|
||||
Deletes the parser and frees the memory it was using. The object
|
||||
should not be used after this call. This call is done automatically
|
||||
when the last reference to the object is removed.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{parseframe}{frame}
|
||||
Parses one or more frames of digital audio data from a CD such as
|
||||
returned by \code{readda}. It determines which subcodes are present
|
||||
in the data. If these subcodes have changed since the last frame,
|
||||
then \code{parseframe} executes a callback of the appropriate type
|
||||
passing to it the subcode data found in the frame.
|
||||
Unlike the C function, more than one frame of digital audio data can
|
||||
be passed to this method.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{removecallback}{type}
|
||||
Removes the callback for the given \code{type}.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{resetparser}{}
|
||||
Resets the fields of the parser used for tracking subcodes to an
|
||||
initial state. \code{resetparser} should be called after the disc has
|
||||
been changed.
|
||||
\end{funcdesc}
|
|
@ -0,0 +1,288 @@
|
|||
\section{Built-in Module \sectcode{cd}}
|
||||
\bimodindex{cd}
|
||||
|
||||
This module provides an interface to the Silicon Graphics CD library.
|
||||
It is available only on Silicon Graphics systems.
|
||||
|
||||
The way the library works is as follows. A program opens the CD-ROM
|
||||
device with \code{cd.open()} and creates a parser to parse the data
|
||||
from the CD with \code{cd.createparser()}. The object returned by
|
||||
\code{cd.open()} can be used to read data from the CD, but also to get
|
||||
status information for the CD-ROM device, and to get information about
|
||||
the CD, such as the table of contents. Data from the CD is passed to
|
||||
the parser, which parses the frames, and calls any callback
|
||||
functions that have previously been added.
|
||||
|
||||
An audio CD is divided into \dfn{tracks} or \dfn{programs} (the terms
|
||||
are used interchangeably). Tracks can be subdivided into
|
||||
\dfn{indices}. An audio CD contains a \dfn{table of contents} which
|
||||
gives the starts of the tracks on the CD. Index 0 is usually the
|
||||
pause before the start of a track. The start of the track as given by
|
||||
the table of contents is normally the start of index 1.
|
||||
|
||||
Positions on a CD can be represented in two ways. Either a frame
|
||||
number or a tuple of three values, minutes, seconds and frames. Most
|
||||
functions use the latter representation. Positions can be both
|
||||
relative to the beginning of the CD, and to the beginning of the
|
||||
track.
|
||||
|
||||
Module \code{cd} defines the following functions:
|
||||
|
||||
\renewcommand{\indexsubitem}{(in module cd)}
|
||||
\begin{funcdesc}{createparser}{}
|
||||
Create and return an opaque parser object. The methods of the parser
|
||||
object are described below.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{msftoframe}{min\, sec\, frame}
|
||||
Converts a \code{(minutes, seconds, frames)} triple representing time
|
||||
in absolute time code into the corresponding CD frame number.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{open}{\optional{device\optional{\, mode}}}
|
||||
Open the CD-ROM device. The return value is an opaque player object;
|
||||
methods of the player object are described below. The device is the
|
||||
name of the SCSI device file, e.g. /dev/scsi/sc0d4l0, or \code{None}.
|
||||
If omited or \code{None}, the hardware inventory is consulted to
|
||||
locate a CD-ROM drive. The \code{mode}, if not omited, should be the
|
||||
string 'r'.
|
||||
\end{funcdesc}
|
||||
|
||||
The module defines the following variables:
|
||||
|
||||
\begin{datadesc}{error}
|
||||
Exception raised on various errors.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{DATASIZE}
|
||||
The size of one frame's worth of audio data. This is the size of the
|
||||
audio data as passed to the callback of type \code{audio}.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{BLOCKSIZE}
|
||||
The size of one uninterpreted frame of audio data.
|
||||
\end{datadesc}
|
||||
|
||||
The following variables are states as returned by \code{getstatus}:
|
||||
|
||||
\begin{datadesc}{READY}
|
||||
The drive is ready for operation loaded with an audio CD.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{NODISC}
|
||||
The drive does not have a CD loaded.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{CDROM}
|
||||
The drive is loaded with a CD-ROM. Subsequent play or read operations
|
||||
will return I/O errors.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{ERROR}
|
||||
An error aoocurred while trying to read the disc or its table of
|
||||
contents.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{PLAYING}
|
||||
The drive is in CD player mode playing an audio CD through its audio
|
||||
jacks.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{PAUSED}
|
||||
The drive is in CD layer mode with play paused.
|
||||
\end{datadesc}
|
||||
|
||||
\begin{datadesc}{STILL}
|
||||
The equivalent of \code{PAUSED} on older (non 3301) model Toshiba
|
||||
CD-ROM drives. Such drives have never been shipped by SGI.
|
||||
\end{datadesc}
|
||||
|
||||
Player objects (returned by \code{cd.open()}) have the following
|
||||
methods:
|
||||
|
||||
\renewcommand{\indexsubitem}{(CD player object method)}
|
||||
\begin{funcdesc}{allowremoval}{}
|
||||
Unlocks the eject button on the CD-ROM drive permitting the user to
|
||||
eject the caddy if desired.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{bestreadsize}{}
|
||||
Returns the best value to use for the \code{num_frames} parameter of
|
||||
the \code{readda} method. Best is defined as the value that permits a
|
||||
continuous flow of data from the CD-ROM drive.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{close}{}
|
||||
Frees the resources associated with the player object. After calling
|
||||
\code{close}, the methods of the object should no longer be used.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{eject}{}
|
||||
Ejects the caddy from the CD-ROM drive.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{getstatus}{}
|
||||
Returns information pertaining to the current state of the CD-ROM
|
||||
drive. The returned information is a tuple with the following values:
|
||||
\code{state}, \code{track}, \code{rtime}, \code{atime}, \code{ttime},
|
||||
\code{first}, \code{last}, \code{scsi_audio}, \code{cur_block}.
|
||||
\code{rtime} is the time relative to the start of the current track;
|
||||
\code{atime} is the time relative to the beginning of the disc;
|
||||
\code{ttime} is the total time on the disc. For more information on
|
||||
the meaning of the values, see the manual for CDgetstatus.
|
||||
The value of \code{state} is one of the following: \code{cd.ERROR},
|
||||
\code{cd.NODISC}, \code{cd.READY}, \code{cd.PLAYING},
|
||||
\code{cd.PAUSED}, \code{cd.STILL}, or \code{cd.CDROM}.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{gettrackinfo}{track}
|
||||
Returns information about the specified track. The returned
|
||||
information is a tuple consisting of two elements, the start time of
|
||||
the track and the duration of the track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{msftoblock}{min\, sec\, frame}
|
||||
Converts a minutes, seconds, frames triple representing a time in
|
||||
absolute time code into the corresponding logical block number for the
|
||||
given CD-ROM drive. You should use \code{cd.msftoframe()} rather than
|
||||
\code{msftoblock()} for comparing times. The logical block number
|
||||
differs from the frame number by an offset required by certain CD-ROM
|
||||
drives.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{play}{start\, play}
|
||||
Starts playback of an audio CD in the CD-ROM drive at the specified
|
||||
track. The audio output appears on the CD-ROM drive's headphone and
|
||||
audio jacks (if fitted). Play stops at the end of the disc.
|
||||
\code{start} is the number of the track at which to start playing the
|
||||
CD; if \code{play} is 0, the CD will be set to an initial paused
|
||||
state. The method \code{togglepause()} can then be used to commence
|
||||
play.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playabs}{min\, sec\, frame\, play}
|
||||
Like \code{play()}, except that the start is given in minutes,
|
||||
seconds, frames instead of a track number.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playtrack}{start\, play}
|
||||
Like \code{play()}, except that playing stops at the end of the track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{playtrackabs}{track\, min\, sec\, frame\, play}
|
||||
Like \code{play()}, except that playing begins at the spcified
|
||||
absolute time and ends at the end of the specified track.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{preventremoval}{}
|
||||
Locks the eject button on the CD-ROM drive thus preventing the user
|
||||
from arbitrarily ejecting the caddy.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{readda}{num_frames}
|
||||
Reads the specified number of frames from an audio CD mounted in the
|
||||
CD-ROM drive. The return value is a string representing the audio
|
||||
frames. This string can be passed unaltered to the \code{parseframe}
|
||||
method of the parser object.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seek}{min\, sec\, frame}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to an absolute
|
||||
time code location specified in minutes, seconds, and frames. The
|
||||
return value is the logical block number to which the pointer has been
|
||||
set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seekblock}{block}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to the specified
|
||||
logical block number. The return value is the logical block number to
|
||||
which the pointer has been set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{seektrack}{track}
|
||||
Sets the pointer that indicates the starting point of the next read of
|
||||
digital audio data from a CD-ROM. The pointer is set to the specified
|
||||
track. The return value is the logical block number to which the
|
||||
pointer has been set.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{stop}{}
|
||||
Stops the current playing operation.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{togglepause}{}
|
||||
Pauses the CD if it is playing, and makes it play if it is paused.
|
||||
\end{funcdesc}
|
||||
|
||||
Parser objects (returned by \code{cd.createparser()}) have the
|
||||
following methods:
|
||||
|
||||
\begin{funcdesc}{addcallback}{type\, func\, arg}
|
||||
Adds a callback for the parser. The parser has callbacks for eight
|
||||
different types of data in the digital audio data stream. The
|
||||
callback is called as follows \code{func(arg, type, data)}.
|
||||
\code{arg} is the user supplied argument, \code{type} is the
|
||||
particular type of callback, and \code{data} is the data returned for
|
||||
this \code{type} of callback. The type of the data depends on the
|
||||
\code{type} of callback as follows.
|
||||
\begin{datadesc}{audio}
|
||||
The argument is a string which can be passed unmodified to
|
||||
\code{al.writesamps}
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{pnum}
|
||||
The argument is an integer giving the program (track) number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{index}
|
||||
The argument is an integer giving the index number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{ptime}
|
||||
The argument is a tuple consisting of the program time in minutes,
|
||||
seconds, and frames.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{atime}
|
||||
The argument is a tuple consisting of the absolute time in minutes,
|
||||
seconds, and frames.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{catalog}
|
||||
The argument is a string of 13 characters, giving the catalog number
|
||||
of the CD.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{ident}
|
||||
The argument is a string of 12 characters, giving the ISRC
|
||||
identification number of the recording. The string consists of two
|
||||
characters country code, three characters owner code, two characters
|
||||
giving the year, and five characters giving a serial number.
|
||||
\end{datadesc}
|
||||
\begin{datadesc}{control}
|
||||
The argument is an integer giving the control bits from the CD subcode
|
||||
data.
|
||||
\end{datadesc}
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{deleteparser}{}
|
||||
Deletes the parser and frees the memory it was using. The object
|
||||
should not be used after this call. This call is done automatically
|
||||
when the last reference to the object is removed.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{parseframe}{frame}
|
||||
Parses one or more frames of digital audio data from a CD such as
|
||||
returned by \code{readda}. It determines which subcodes are present
|
||||
in the data. If these subcodes have changed since the last frame,
|
||||
then \code{parseframe} executes a callback of the appropriate type
|
||||
passing to it the subcode data found in the frame.
|
||||
Unlike the C function, more than one frame of digital audio data can
|
||||
be passed to this method.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{removecallback}{type}
|
||||
Removes the callback for the given \code{type}.
|
||||
\end{funcdesc}
|
||||
|
||||
\begin{funcdesc}{resetparser}{}
|
||||
Resets the fields of the parser used for tracking subcodes to an
|
||||
initial state. \code{resetparser} should be called after the disc has
|
||||
been changed.
|
||||
\end{funcdesc}
|
Loading…
Reference in New Issue