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diff --git a/Doc/lib/libimghdr.tex b/Doc/lib/libimghdr.tex new file mode 100644 index 0000000..22d4d0d --- /dev/null +++ b/Doc/lib/libimghdr.tex @@ -0,0 +1,60 @@ +\section{Standard module \sectcode{imghdr}} +\stmodindex{imghdr} + +The \code{imghdr} module determines the type of image contained in a +file or byte stream. + +The \code{imghdr} module defines the following function: + +\renewcommand{\indexsubitem}{(in module imghdr)} + +\begin{funcdesc}{what}{filename\optional{\, h}} +Tests the image data contained in the file named by \var{filename}, +and returns a string describing the image type. If optional \var{h} +is provided, the \var{filename} is ignored and \var{h} is assumed to +contain the byte stream to test. +\end{funcdesc} + +The following image types are recognized, as listed below with the +return value from \code{what}: + +\begin{enumerate} +\item[``rgb''] SGI ImgLib Files + +\item[``gif''] GIF 87a and 89a Files + +\item[``pbm''] Portable Bitmap Files + +\item[``pgm''] Portable Graymap Files + +\item[``ppm''] Portable Pixmap Files + +\item[``tiff''] TIFF Files + +\item[``rast''] Sun Raster Files + +\item[``xbm''] X Bitmap Files + +\item[``jpeg''] JPEG data in JIFF format +\end{enumerate} + +You can extend the list of file types \code{imghdr} can recognize by +appending to this variable: + +\begin{datadesc}{tests} +A list of functions performing the individual tests. Each function +takes two arguments: the byte-stream and an open file-like object. +When \code{what()} is called with a byte-stream, the file-like +object will be \code{None}. + +The test function should return a string describing the image type if +the test succeeded, or \code{None} if it failed. +\end{datadesc} + +Example: + +\begin{verbatim} +>>> import imghdr +>>> imghdr.what('/tmp/bass.gif') +'gif' +\end{verbatim} |