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<a href='#toc'>Table of Contents</a><p>
<h2><a name='sect0' href='#toc0'>Name</a></h2>
IM_IMAGE_ADDR, IM_IMAGE_SIZEOF_ELEMENT, IM_IMAGE_SIZEOF_PEL, IM_IMAGE_SIZEOF_LINE,
IM_IMAGE_N_ELEMENTS - macros for images
<h2><a name='sect1' href='#toc1'>Synopsis</a></h2>
<b>#include <vips/vips.h></b>
<p> int
IM_IMAGE_SIZEOF_ELEMENT( im ) <br>
IMAGE *im;
<p> int IM_IMAGE_SIZEOF_PEL( im ) <br>
IMAGE *im;
<p> int IM_IMAGE_SIZEOF_LINE( im ) <br>
IMAGE *im;
<p> int IM_IMAGE_N_ELEMENTS( im ) <br>
IMAGE *im;
<p> char *IM_IMAGE_ADDR( im, x, y ) <br>
IMAGE *im; <br>
int x; <br>
int y;
<p>
<h2><a name='sect2' href='#toc2'>Description</a></h2>
These macros help to simplify address arithmetic for
images.
<p> <a href='IM_IMAGE_SIZEOF_ELEMENT.3.html'>IM_IMAGE_SIZEOF_ELEMENT(3)</a>
returns sizeof( one band element ).
<p> <a href='IM_IMAGE_SIZEOF_PEL.3.html'>IM_IMAGE_SIZEOF_PEL(3)</a>
returns sizeof( one pel ).
<p> <a href='IM_IMAGE_SIZEOF_LINE.3.html'>IM_IMAGE_SIZEOF_LINE(3)</a>
returns sizeof( one horizontal line of pels ).
<p> <a href='IM_IMAGE_N_ELEMENTS.3.html'>IM_IMAGE_N_ELEMENTS(3)</a>
returns
the number of band elements across a horizontal line.
<p> <a href='IM_IMAGE_ADDR.3.html'>IM_IMAGE_ADDR(3)</a>
returns a pointer to the pixel at position (x,y) in the image. The point
(x,y) should lie within the image.
<p> If the macro DEBUG has been defined,
then <a href='IM_IMAGE_ADDR.3.html'>IM_IMAGE_ADDR(3)</a>
will also perform bounds checking. If you ask for
the address of a pel outside the image, then <a href='IM_IMAGE_ADDR.3.html'>IM_IMAGE_ADDR(3)</a>
will print
an error message of the form:
<p> IM_IMAGE_ADDR: point out of bounds,
file "test.c", line 18<br>
(point x=50, y=0 <br>
should have been within Rect left=0, top=0, width=50, height=50)<br>
<p> and call <a href='abort.3.html'>abort(3)</a>
.
<p> DEBUG needs to be defined *before* vips.h is included.
Either define DEBUG with -D in your Makefile, or have a #define DEBUG right
at the top of your file.
<h2><a name='sect3' href='#toc3'>Copyright</a></h2>
National Gallery, 1993
<h2><a name='sect4' href='#toc4'>See Also</a></h2>
<a href='IM_REGION_ADDR.3.html'>IM_REGION_ADDR(3)</a>
,
<a href='im_malloc.3.html'>im_malloc(3)</a>
, <a href='im_open_local.3.html'>im_open_local(3)</a>
.
<h2><a name='sect5' href='#toc5'>Author</a></h2>
J. Cupitt - 23/7/93 <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'>Copyright</a></li>
<li><a name='toc4' href='#sect4'>See Also</a></li>
<li><a name='toc5' href='#sect5'>Author</a></li>
</ul>
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Mandriva
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2010.0
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i586
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media
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contrib-release
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by-pkgid
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7faa4cd12598db7d59564e3dc9a0913c
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files
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