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diff --git a/Doc/library/jpeg.rst b/Doc/library/jpeg.rst deleted file mode 100644 index 2a8e4e8..0000000 --- a/Doc/library/jpeg.rst +++ /dev/null @@ -1,95 +0,0 @@ - -: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 removed in Python 3. - - - -.. 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. - |