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diff --git a/Doc/lib/libwave.tex b/Doc/lib/libwave.tex new file mode 100644 index 0000000..8510f49 --- /dev/null +++ b/Doc/lib/libwave.tex @@ -0,0 +1,165 @@ +% Documentations stolen and LaTeX'ed from comments in file. +\section{\module{wave} --- + Read and write .WAV files} + +\declaremodule{standard}{wave} +\sectionauthor{Moshe Zadka}{mzadka@geocities.com} +\modulesynopsis{Provide an interface to the WAV sound format.} + +The \module{wave} module provides a convenient interface to the WAV sound +format. It does not support compression/decompression, but it does support +mono/stereo. + +The \module{wave} module defines the following function: + +\begin{funcdesc}{open}{file, mode} +If \var{file} is a string, open the file by that name, other treat it +as a seekable file-like object. \var{mode} can be any of +\begin{description} + \item[\code{'r'}, \code{'rb'}] Read only mode. + \item[\code{'w'}, \code{'wb'}] Write only mode. +\end{description} +Note that it does not allow read/write WAV files. + +A \var{mode} of \code{'r'} or \code{'rb'} returns a \class{Wave_read} +object, while a \var{mode} of \code{'w'} or \code{'wb'} returns +a \class{Wave_write} object. +\end{funcdesc} + +\begin{funcdesc}{openfp}{file, mode} +A synonym for \function{open()}, maintained for backwards compatibility. +\end{funcdesc} + +\begin{excdesc}{Error} +An error raised when something is impossible because it violates the +WAV specification or hits an implementation deficiency. +\end{excdesc} + + +\subsection{Wave_read Objects \label{Wave-read-objects}} + +Wave_read objects, as returned by \function{open()} above, have the +following methods: + +\begin{methoddesc}[Wave_read]{getnchannels}{} +Returns number of audio channels (1 for mone, 2 for stereo). +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getsampwidth}{} +Returns sample width in bytes. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getframerate}{} +Returns sampling frequency. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getnframes}{} +Returns number of audio frames. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getcomptype}{} +Returns compression type (\code{'NONE'} is the only supported type). +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getcompname}{} +Human-readable version of \method{getcomptype()}. +Usually \code{'not compressed'} parallels \code{'NONE'}. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getparams}{} +Returns a tuple +\code{(nchannels, sampwidth, framerate, nframes, comptype, compname)}, +equivalent to output of the \code{get} methods. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{readframes}{n} +Reads and returns at most \var{n} frames of audio, as a string of bytes. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{rewind}{} +Rewind the file pointer to the beginning of the audio stream. +\end{methoddesc} + +The following two functions are defined for compatibility with the +\refmodule{aifc} module, and don't do anything interesting. + +\begin{methoddesc}[Wave_read]{getmarkers}{} +Returns \code{None}. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{getmark}{id} +Raise an error. +\end{methoddesc} + +The following two methods define a term ``position'' which is compatible +between them, and is otherwise implementation dependant. + +\begin{methoddesc}[Wave_read]{setpos}{pos} +Set the file pointer to the specified position. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{tell}{} +Return current file pointer position. +\end{methoddesc} + +\begin{methoddesc}[Wave_read]{close}{} +Close the stream, and make the instance unusable. (This is +called automatically on deletion. +\end{methoddesc} + + +\subsection{Wave_write Objects \label{Wave-write-objects}} + +Wave_write objects, as returned by \function{open()} above, have the +following methods: + +\begin{methoddesc}[Wave_write]{setnchannels}{n} +Set the number of channels. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{setsampwidth}{n} +Set the sample width (in bytes.) +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{setframerate}{n} +Set the frame rate. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{setnframes}{n} +Set the number of frames. This can be later changed, when and if more +frames are written. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{setcomptype}{type, name} +Set the compression type and description. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{setparams}{tuple} +The \var{tuple} should be +\code{(\var{nchannels}, \var{sampwidth}, \var{framerate}, +\var{nframes}, \var{comptype}, \var{compname})}, with values valid for +the \code{set} methods. Set all parameters. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{tell}{} +Return current position in the file, with the same disclaimer for +the \method{Wave_read.tell} and \method{Wave_read.setpos} methods. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{writeframesraw}{data} +Write audio frames, without correcting \var{nframes}. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{writeframes}{data} +Write audio frames and make sure \var{nframes} is correct. +\end{methoddesc} + +\begin{methoddesc}[Wave_write]{close}{} +Make sure \var{nframes} is correct, and close the file. + +This method is called upon deletion. +\end{methoddesc} + +Note that it is invalid to set any parameters after calling +\method{writeframes()} or \method{writeframesraw()}, and any attempt +to do so will raise an error. |