<!-- manual page source format generated by PolyglotMan v3.2, --> <!-- available at http://polyglotman.sourceforge.net/ --> <html> <head> <title>IM_CORREL(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_correl - search for image match <h2><a name='sect1' href='#toc1'>Synopsis</a></h2> #include <vips/vips.h> <p> int <br> im_correl( IMAGE *ref, IMAGE *sec, <br> int xref, int yref, int xsec, int ysec,<br> <br> int hwindowsize, int hsearchsize,<br> <br> double *correlation, int *x, int *y )<br> <p> <h2><a name='sect2' href='#toc2'>Description</a></h2> im_correl() is the base image-searching function used by the mosaicing functions im_lrmosaic() and im_tbmosaic(), and by the matching funtions im_match_linear() and im_match_linear_search(). <p> It finds the position of the secondary image <b>sec </b> within <b>ref.</b> It searches the area around <b>xsec</b> , <b>ysec</b> for the best match for the area around <b>xref</b> , <b>yref.</b> It searches an area of size <b>hsearchsize</b> for a match of size <b>hwindowsize.</b> The position of the best match is returned, together with the correlation at that point. <p> Only the first band of each image is correlated. ref and sec may be very large --- the function extracts and generated just the parts needed. Correlation is done with im_spcor(); the position of the maximum is found with im_maxpos(). <h2><a name='sect3' href='#toc3'>See Also</a></h2> <a href='im_fastcor.3.html'>im_fastcor(3)</a> , <a href='im_spcor.3.html'>im_spcor(3)</a> , <a href='im_maxpos.3.html'>im_maxpos(3)</a> , <a href='im_match_linear.3.html'>im_match_linear(3)</a> , <a href='im_lrmosaic.3.html'>im_lrmosaic(3)</a> . <h2><a name='sect4' href='#toc4'>Author</a></h2> J.Cupitt - 22/02/93 <h2><a name='sect5' href='#toc5'>Copyright</a></h2> The National Gallery and Birkbeck College, 1989-1996. <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'>See Also</a></li> <li><a name='toc4' href='#sect4'>Author</a></li> <li><a name='toc5' href='#sect5'>Copyright</a></li> </ul> </body> </html>