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diff --git a/Doc/libjpeg.tex b/Doc/libjpeg.tex deleted file mode 100644 index 76e70af..0000000 --- a/Doc/libjpeg.tex +++ /dev/null @@ -1,57 +0,0 @@ -\section{Built-in Module \module{jpeg}} -\label{module-jpeg} -\bimodindex{jpeg} - -The module \module{jpeg} provides access to the jpeg compressor and -decompressor written by the Independent JPEG Group% -\index{Independent JPEG Group}% -. JPEG is a (draft?) -standard for compressing pictures. For details on JPEG or the -Independent JPEG Group software refer to the JPEG standard or the -documentation provided with the software. - -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} |