define GScaler.h

Rescaling images with bilinear interpolation.

o GScaler
Base class for GBitmapScaler and GPixmapScaler.
o GBitmapScaler
Fast rescaling code for gray level images.
o GPixmapScaler
Fast rescaling code for color images.
Files "GScaler.h" and "GScaler.cpp" implement a fast bilinear interpolation scheme to rescale a GBitmap or a GPixmap. Common setup functions are implemented by the base class GScaler. The actual function for rescaling a gray level image is implemented by class GBitmapScaler. The actual function for rescaling a color image is implemented by class GPixmapScaler.

Remark --- The bilinear interpolation code relies on fixed precision tables. It becomes suboptimal when upsampling (i.e. zooming into) an image by a factor greater than eight. High contrast images displayed at high magnification may contain visible jaggies.

Author:
Léon Bottou <leonb@research.att.com>
Version:
$Id: GScaler.h.html,v 1.2 2000/08/26 00:09:29 bcr Exp $

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