--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Doc/library/jpeg.rst Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,95 @@
+
+:mod:`jpeg` --- Read and write JPEG files
+=========================================
+
+.. module:: jpeg
+ :platform: IRIX
+ :synopsis: Read and write image files in compressed JPEG format.
+ :deprecated:
+
+.. deprecated:: 2.6
+ The :mod:`jpeg` module has been deprecated for removal in Python 3.0.
+
+
+
+.. index:: single: Independent JPEG Group
+
+The module :mod:`jpeg` provides access to the jpeg compressor and decompressor
+written by the 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.
+
+.. index::
+ single: Python Imaging Library
+ single: PIL (the Python Imaging Library)
+ single: Lundh, Fredrik
+
+A portable interface to JPEG image files is available with the Python Imaging
+Library (PIL) by Fredrik Lundh. Information on PIL is available at
+http://www.pythonware.com/products/pil/.
+
+The :mod:`jpeg` module defines an exception and some functions.
+
+
+.. exception:: error
+
+ Exception raised by :func:`compress` and :func:`decompress` in case of errors.
+
+
+.. function:: compress(data, w, h, b)
+
+ .. index:: single: JFIF
+
+ Treat data as a pixmap of width *w* and height *h*, with *b* bytes per pixel.
+ The data is in SGI GL order, so the first pixel is in the lower-left corner.
+ This means that :func:`gl.lrectread` return data can immediately be passed to
+ :func:`compress`. Currently only 1 byte and 4 byte pixels are allowed, the
+ former being treated as greyscale and the latter as RGB color. :func:`compress`
+ returns a string that contains the compressed picture, in JFIF format.
+
+
+.. function:: decompress(data)
+
+ .. index:: single: JFIF
+
+ Data is a string containing a picture in JFIF format. It returns a tuple
+ ``(data, width, height, bytesperpixel)``. Again, the data is suitable to pass
+ to :func:`gl.lrectwrite`.
+
+
+.. function:: setoption(name, value)
+
+ Set various options. Subsequent :func:`compress` and :func:`decompress` calls
+ will use these options. The following options are available:
+
+ +-----------------+---------------------------------------------+
+ | Option | Effect |
+ +=================+=============================================+
+ | ``'forcegray'`` | Force output to be grayscale, even if input |
+ | | is RGB. |
+ +-----------------+---------------------------------------------+
+ | ``'quality'`` | Set the quality of the compressed image to |
+ | | a value between ``0`` and ``100`` (default |
+ | | is ``75``). This only affects compression. |
+ +-----------------+---------------------------------------------+
+ | ``'optimize'`` | Perform Huffman table optimization. Takes |
+ | | longer, but results in smaller compressed |
+ | | image. This only affects compression. |
+ +-----------------+---------------------------------------------+
+ | ``'smooth'`` | Perform inter-block smoothing on |
+ | | uncompressed image. Only useful for low- |
+ | | quality images. This only affects |
+ | | decompression. |
+ +-----------------+---------------------------------------------+
+
+
+.. seealso::
+
+ JPEG Still Image Data Compression Standard
+ The canonical reference for the JPEG image format, by Pennebaker and Mitchell.
+
+ `Information Technology - Digital Compression and Coding of Continuous-tone Still Images - Requirements and Guidelines <http://www.w3.org/Graphics/JPEG/itu-t81.pdf>`_
+ The ISO standard for JPEG is also published as ITU T.81. This is available
+ online in PDF form.
+