/Doc/library/imgfile.rst
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- :mod:`imgfile` --- Support for SGI imglib files
- ===============================================
- .. module:: imgfile
- :platform: IRIX
- :synopsis: Support for SGI imglib files.
- :deprecated:
- .. deprecated:: 2.6
- The :mod:`imgfile` module has been deprecated for removal in Python 3.0.
- The :mod:`imgfile` module allows Python programs to access SGI imglib image
- files (also known as :file:`.rgb` files). The module is far from complete, but
- is provided anyway since the functionality that there is enough in some cases.
- Currently, colormap files are not supported.
- The module defines the following variables and functions:
- .. exception:: error
- This exception is raised on all errors, such as unsupported file type, etc.
- .. function:: getsizes(file)
- This function returns a tuple ``(x, y, z)`` where *x* and *y* are the size of
- the image in pixels and *z* is the number of bytes per pixel. Only 3 byte RGB
- pixels and 1 byte greyscale pixels are currently supported.
- .. function:: read(file)
- This function reads and decodes the image on the specified file, and returns it
- as a Python string. The string has either 1 byte greyscale pixels or 4 byte RGBA
- pixels. The bottom left pixel is the first in the string. This format is
- suitable to pass to :func:`gl.lrectwrite`, for instance.
- .. function:: readscaled(file, x, y, filter[, blur])
- This function is identical to read but it returns an image that is scaled to the
- given *x* and *y* sizes. If the *filter* and *blur* parameters are omitted
- scaling is done by simply dropping or duplicating pixels, so the result will be
- less than perfect, especially for computer-generated images.
- Alternatively, you can specify a filter to use to smooth the image after
- scaling. The filter forms supported are ``'impulse'``, ``'box'``,
- ``'triangle'``, ``'quadratic'`` and ``'gaussian'``. If a filter is specified
- *blur* is an optional parameter specifying the blurriness of the filter. It
- defaults to ``1.0``.
- :func:`readscaled` makes no attempt to keep the aspect ratio correct, so that is
- the users' responsibility.
- .. function:: ttob(flag)
- This function sets a global flag which defines whether the scan lines of the
- image are read or written from bottom to top (flag is zero, compatible with SGI
- GL) or from top to bottom(flag is one, compatible with X). The default is zero.
- .. function:: write(file, data, x, y, z)
- This function writes the RGB or greyscale data in *data* to image file *file*.
- *x* and *y* give the size of the image, *z* is 1 for 1 byte greyscale images or
- 3 for RGB images (which are stored as 4 byte values of which only the lower
- three bytes are used). These are the formats returned by :func:`gl.lrectread`.