Doc/lib/librgbimg.tex

   1 \section{\module{rgbimg} ---
   2          Read and write ``SGI RGB'' files}
   3
   4 \declaremodule{builtin}{rgbimg}
   5 \modulesynopsis{Read and write image files in ``SGI RGB'' format (the module
   6                 is \emph{not} SGI specific though!).}
   7
   8 \deprecated{2.5}{This module is not maintained anymore and seems to be
   9                  unused.}
  10
  11 The \module{rgbimg} module allows Python programs to access SGI imglib image
  12 files (also known as \file{.rgb} files).  The module is far from
  13 complete, but is provided anyway since the functionality that there is
  14 enough in some cases.  Currently, colormap files are not supported.
  15
  16 \note{This module is only built by default for 32-bit platforms; it is
  17 not expected to work properly on other systems.}
  18
  19 The module defines the following variables and functions:
  20
  21 \begin{excdesc}{error}
  22 This exception is raised on all errors, such as unsupported file type, etc.
  23 \end{excdesc}
  24
  25 \begin{funcdesc}{sizeofimage}{file}
  26 This function returns a tuple \code{(\var{x}, \var{y})} where
  27 \var{x} and \var{y} are the size of the image in pixels.
  28 Only 4 byte RGBA pixels, 3 byte RGB pixels, and 1 byte greyscale pixels
  29 are currently supported.
  30 \end{funcdesc}
  31
  32 \begin{funcdesc}{longimagedata}{file}
  33 This function reads and decodes the image on the specified file, and
  34 returns it as a Python string. The string has 4 byte RGBA pixels.
  35 The bottom left pixel is the first in
  36 the string. This format is suitable to pass to \function{gl.lrectwrite()},
  37 for instance.
  38 \end{funcdesc}
  39
  40 \begin{funcdesc}{longstoimage}{data, x, y, z, file}
  41 This function writes the RGBA data in \var{data} to image
  42 file \var{file}. \var{x} and \var{y} give the size of the image.
  43 \var{z} is 1 if the saved image should be 1 byte greyscale, 3 if the
  44 saved image should be 3 byte RGB data, or 4 if the saved images should
  45 be 4 byte RGBA data.  The input data always contains 4 bytes per pixel.
  46 These are the formats returned by \function{gl.lrectread()}.
  47 \end{funcdesc}
  48
  49 \begin{funcdesc}{ttob}{flag}
  50 This function sets a global flag which defines whether the scan lines
  51 of the image are read or written from bottom to top (flag is zero,
  52 compatible with SGI GL) or from top to bottom (flag is one,
  53 compatible with X).  The default is zero.
  54 \end{funcdesc}