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+\section{\module{jpeg} ---
+         Read and write JPEG files}
+
+\declaremodule{builtin}{jpeg}
+  \platform{IRIX}
+\modulesynopsis{Read and write image files in compressed JPEG format.}
+
+
+The module \module{jpeg} provides access to the jpeg compressor and
+decompressor written by the Independent JPEG Group
+\index{Independent JPEG Group}(IJG). JPEG is a standard for
+compressing pictures; it is defined in ISO 10918.  For details on JPEG
+or the Independent JPEG Group software refer to the JPEG standard or
+the documentation provided with the software.
+
+A portable interface to JPEG image files is available with the Python
+Imaging Library (PIL) by Fredrik Lundh.  Information on PIL is
+available at \url{http://www.pythonware.com/products/pil/}.
+\index{Python Imaging Library}
+\index{PIL (the Python Imaging Library)}
+\index{Lundh, Fredrik}
+
+The \module{jpeg} module defines an exception and some functions.
+
+\begin{excdesc}{error}
+Exception raised by \function{compress()} and \function{decompress()}
+in case of errors.
+\end{excdesc}
+
+\begin{funcdesc}{compress}{data, w, h, b}
+Treat data as a pixmap of width \var{w} and height \var{h}, with
+\var{b} bytes per pixel.  The data is in SGI GL order, so the first
+pixel is in the lower-left corner. This means that \function{gl.lrectread()}
+return data can immediately be passed to \function{compress()}.
+Currently only 1 byte and 4 byte pixels are allowed, the former being
+treated as greyscale and the latter as RGB color.
+\function{compress()} returns a string that contains the compressed
+picture, in JFIF\index{JFIF} format.
+\end{funcdesc}
+
+\begin{funcdesc}{decompress}{data}
+Data is a string containing a picture in JFIF\index{JFIF} format. It
+returns a tuple \code{(\var{data}, \var{width}, \var{height},
+\var{bytesperpixel})}.  Again, the data is suitable to pass to
+\function{gl.lrectwrite()}.
+\end{funcdesc}
+
+\begin{funcdesc}{setoption}{name, value}
+Set various options.  Subsequent \function{compress()} and
+\function{decompress()} calls will use these options.  The following
+options are available:
+
+\begin{tableii}{l|p{3in}}{code}{Option}{Effect}
+  \lineii{'forcegray'}{%
+    Force output to be grayscale, even if input is RGB.}
+  \lineii{'quality'}{%
+    Set the quality of the compressed image to a value between
+    \code{0} and \code{100} (default is \code{75}).  This only affects
+    compression.}
+  \lineii{'optimize'}{%
+    Perform Huffman table optimization.  Takes longer, but results in
+    smaller compressed image.  This only affects compression.}
+  \lineii{'smooth'}{%
+    Perform inter-block smoothing on uncompressed image.  Only useful
+    for low-quality images.  This only affects decompression.}
+\end{tableii}
+\end{funcdesc}
+
+
+\begin{seealso}
+  \seetitle{JPEG Still Image Data Compression Standard}{The 
+            canonical reference for the JPEG image format, by
+            Pennebaker and Mitchell.}
+
+  \seetitle[http://www.w3.org/Graphics/JPEG/itu-t81.pdf]{Information
+            Technology - Digital Compression and Coding of
+            Continuous-tone Still Images - Requirements and
+            Guidelines}{The ISO standard for JPEG is also published as
+            ITU T.81.  This is available online in PDF form.}
+\end{seealso}