ref: c7d9da8f5a41b833946027c802e0e8d7dd014b22
dir: /sys/src/cmd/python/Doc/lib/libsndhdr.tex/
\section{\module{sndhdr} --- Determine type of sound file} \declaremodule{standard}{sndhdr} \modulesynopsis{Determine type of a sound file.} \sectionauthor{Fred L. Drake, Jr.}{[email protected]} % Based on comments in the module source file. The \module{sndhdr} provides utility functions which attempt to determine the type of sound data which is in a file. When these functions are able to determine what type of sound data is stored in a file, they return a tuple \code{(\var{type}, \var{sampling_rate}, \var{channels}, \var{frames}, \var{bits_per_sample})}. The value for \var{type} indicates the data type and will be one of the strings \code{'aifc'}, \code{'aiff'}, \code{'au'}, \code{'hcom'}, \code{'sndr'}, \code{'sndt'}, \code{'voc'}, \code{'wav'}, \code{'8svx'}, \code{'sb'}, \code{'ub'}, or \code{'ul'}. The \var{sampling_rate} will be either the actual value or \code{0} if unknown or difficult to decode. Similarly, \var{channels} will be either the number of channels or \code{0} if it cannot be determined or if the value is difficult to decode. The value for \var{frames} will be either the number of frames or \code{-1}. The last item in the tuple, \var{bits_per_sample}, will either be the sample size in bits or \code{'A'} for A-LAW\index{A-LAW} or \code{'U'} for u-LAW\index{u-LAW}. \begin{funcdesc}{what}{filename} Determines the type of sound data stored in the file \var{filename} using \function{whathdr()}. If it succeeds, returns a tuple as described above, otherwise \code{None} is returned. \end{funcdesc} \begin{funcdesc}{whathdr}{filename} Determines the type of sound data stored in a file based on the file header. The name of the file is given by \var{filename}. This function returns a tuple as described above on success, or \code{None}. \end{funcdesc}