<!-- manual page source format generated by PolyglotMan v3.2, --> <!-- available at http://polyglotman.sourceforge.net/ --> <html> <head> <title>IM_CONTRAST_SURFACE(3) manual page</title> </head> <body bgcolor='white'> <a href='#toc'>Table of Contents</a><p> <h2><a name='sect0' href='#toc0'>Name</a></h2> im_contrast_surface, im_contrast_surface_raw - Generate contrast surface<br> <h2><a name='sect1' href='#toc1'>Synopsis</a></h2> <br> <pre>#include <vips/vips.h> int im_contrast_surface( IMAGE *in, IMAGE *out, int half_win_size, int spacing ); int im_contrast_surface_raw( IMAGE *in, IMAGE *out, int half_win_size, int spacing );</pre> <h2><a name='sect2' href='#toc2'></b>Description</a></h2> These functions generate an image where the value of each pixel represents the contrast within a square window of size 2 * half_win_size + 1 centred on the corresponsing point in the input image. <p> The output is sub-sampled by a factor of spacing. <p> Input must be single-band uncoded uchar, WIO or PIO. <p> Output is single-band uncoded uint, WIO or PIO. <p> In <a href='im_contrast_surface.3.html'><b>im_contrast_surface(3)</b></a> , pixels beyond the edges of the input image are considered to be have the value of the nearest pixel which is in the image. <p> Alternatively, in <a href='im_contrast_surface_raw.3.html'><b>im_contrast_surface_raw(3)</b></a> , pixels within half_win_size of the edge are not calculated, and output is smaller accordingly. <h2><a name='sect3' href='#toc3'>Return Value</a></h2> The functions returns 0 on success and -1 on error. <h2><a name='sect4' href='#toc4'>Copyright</a></h2> <br> Copyright 2006, The Nottingham Trent University. <h2><a name='sect5' href='#toc5'>Author</a></h2> Tom Vajzovic <p> <p> <hr><p> <a name='toc'><b>Table of Contents</b></a><p> <ul> <li><a name='toc0' href='#sect0'>Name</a></li> <li><a name='toc1' href='#sect1'>Synopsis</a></li> <li><a name='toc2' href='#sect2'>Description</a></li> <li><a name='toc3' href='#sect3'>Return Value</a></li> <li><a name='toc4' href='#sect4'>Copyright</a></li> <li><a name='toc5' href='#sect5'>Author</a></li> </ul> </body> </html>