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<title>header: VIPS Reference Manual</title>
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<a href="#" class="shortcut">Top</a><span id="nav_description"> <span class="dim">|</span>
<a href="#libvips-header.description" class="shortcut">Description</a></span>
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<div class="refentry">
<a name="libvips-header"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="libvips-header.top_of_page"></a>header</span></h2>
<p>header — get, set and walk image headers</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="libvips-header.stability-level"></a><h2>Stability Level</h2>
<acronym title="The intention of a Stable interface is to enable arbitrary third parties to
develop applications to these interfaces, release them, and have confidence that
they will run on all minor releases of the product (after the one in which the
interface was introduced, and within the same major release). Even at a major
release, incompatible changes are expected to be rare, and to have strong
justifications.
"><span class="acronym">Stable</span></acronym>, unless otherwise indicated
</div>
<div class="refsect1">
<a name="libvips-header.functions"></a><h2>Functions</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="functions_return">
<col class="functions_name">
</colgroup>
<tbody>
<tr>
<td class="function_type">
<span class="returnvalue">guint64</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-format-sizeof" title="vips_format_sizeof ()">vips_format_sizeof</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">guint64</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-format-sizeof-unsafe" title="vips_format_sizeof_unsafe ()">vips_format_sizeof_unsafe</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-width" title="vips_image_get_width ()">vips_image_get_width</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-height" title="vips_image_get_height ()">vips_image_get_height</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-bands" title="vips_image_get_bands ()">vips_image_get_bands</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="returnvalue">VipsBandFormat</span></a>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-format" title="vips_image_get_format ()">vips_image_get_format</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="returnvalue">VipsBandFormat</span></a>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-guess-format" title="vips_image_guess_format ()">vips_image_guess_format</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="VipsImage.html#VipsCoding" title="enum VipsCoding"><span class="returnvalue">VipsCoding</span></a>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-coding" title="vips_image_get_coding ()">vips_image_get_coding</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="returnvalue">VipsInterpretation</span></a>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-interpretation" title="vips_image_get_interpretation ()">vips_image_get_interpretation</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="returnvalue">VipsInterpretation</span></a>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-guess-interpretation" title="vips_image_guess_interpretation ()">vips_image_guess_interpretation</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">double</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-xres" title="vips_image_get_xres ()">vips_image_get_xres</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">double</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-yres" title="vips_image_get_yres ()">vips_image_get_yres</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-xoffset" title="vips_image_get_xoffset ()">vips_image_get_xoffset</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-yoffset" title="vips_image_get_yoffset ()">vips_image_get_yoffset</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-filename" title="vips_image_get_filename ()">vips_image_get_filename</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-mode" title="vips_image_get_mode ()">vips_image_get_mode</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">double</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-scale" title="vips_image_get_scale ()">vips_image_get_scale</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">double</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-offset" title="vips_image_get_offset ()">vips_image_get_offset</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">void</span> *
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-data" title="vips_image_get_data ()">vips_image_get_data</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-init-fields" title="vips_image_init_fields ()">vips_image_init_fields</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()">vips_image_set</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()">vips_image_get</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-as-string" title="vips_image_get_as_string ()">vips_image_get_as_string</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">GType</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()">vips_image_get_typeof</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">gboolean</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-remove" title="vips_image_remove ()">vips_image_remove</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span> *
</td>
<td class="function_name">
<span class="c_punctuation">(</span><a class="link" href="libvips-header.html#VipsImageMapFn" title="VipsImageMapFn ()">*VipsImageMapFn</a><span class="c_punctuation">)</span> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span> *
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-map" title="vips_image_map ()">vips_image_map</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set-area" title="vips_image_set_area ()">vips_image_set_area</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-area" title="vips_image_get_area ()">vips_image_get_area</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set-blob" title="vips_image_set_blob ()">vips_image_set_blob</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-blob" title="vips_image_get_blob ()">vips_image_get_blob</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-int" title="vips_image_get_int ()">vips_image_get_int</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set-int" title="vips_image_set_int ()">vips_image_set_int</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()">vips_image_get_double</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set-double" title="vips_image_set_double ()">vips_image_set_double</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-string" title="vips_image_get_string ()">vips_image_get_string</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">void</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-set-string" title="vips_image_set_string ()">vips_image_set_string</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-history-printf" title="vips_image_history_printf ()">vips_image_history_printf</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">
<span class="returnvalue">int</span>
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-history-args" title="vips_image_history_args ()">vips_image_history_args</a> <span class="c_punctuation">()</span>
</td>
</tr>
<tr>
<td class="function_type">const <span class="returnvalue">char</span> *
</td>
<td class="function_name">
<a class="link" href="libvips-header.html#vips-image-get-history" title="vips_image_get_history ()">vips_image_get_history</a> <span class="c_punctuation">()</span>
</td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="libvips-header.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-EXIF-NAME:CAPS" title="VIPS_META_EXIF_NAME">VIPS_META_EXIF_NAME</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-XMP-NAME:CAPS" title="VIPS_META_XMP_NAME">VIPS_META_XMP_NAME</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-IPCT-NAME:CAPS" title="VIPS_META_IPCT_NAME">VIPS_META_IPCT_NAME</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-PHOTOSHOP-NAME:CAPS" title="VIPS_META_PHOTOSHOP_NAME">VIPS_META_PHOTOSHOP_NAME</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-ICC-NAME:CAPS" title="VIPS_META_ICC_NAME">VIPS_META_ICC_NAME</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-XML:CAPS" title="VIPS_META_XML">VIPS_META_XML</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-IMAGEDESCRIPTION:CAPS" title="VIPS_META_IMAGEDESCRIPTION">VIPS_META_IMAGEDESCRIPTION</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-RESOLUTION-UNIT:CAPS" title="VIPS_META_RESOLUTION_UNIT">VIPS_META_RESOLUTION_UNIT</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-LOADER:CAPS" title="VIPS_META_LOADER">VIPS_META_LOADER</a></td>
</tr>
<tr>
<td class="define_keyword">#define</td>
<td class="function_name"><a class="link" href="libvips-header.html#VIPS-META-ORIENTATION:CAPS" title="VIPS_META_ORIENTATION">VIPS_META_ORIENTATION</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="libvips-header.includes"></a><h2>Includes</h2>
<pre class="synopsis">#include <vips/vips.h>
</pre>
</div>
<div class="refsect1">
<a name="libvips-header.description"></a><h2>Description</h2>
<p>These functions let you get at image header data (including metadata) in a
uniform way. </p>
<p>Use <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a> to test for the
existance and <span class="type">GType</span>
of a header field.</p>
<p>You can attach arbitrary metadata to images. Metadata is copied as images
are processed, so all images which used this image as input, directly or
indirectly, will have this same bit of metadata attached to them. Copying
is implemented with reference-counted pointers, so it is efficient, even for
large items of data. This does however mean that metadata items need to be
immutable. Metadata is handy for things like ICC profiles or EXIF data.</p>
<p>Various convenience functions (eg. <a class="link" href="libvips-header.html#vips-image-set-int" title="vips_image_set_int ()"><code class="function">vips_image_set_int()</code></a>) let you easily
attach
simple types like
numbers, strings and memory blocks to images. Use <a class="link" href="libvips-header.html#vips-image-map" title="vips_image_map ()"><code class="function">vips_image_map()</code></a> to loop
over an image's fields, including all metadata.</p>
<p>Items of metadata are identified by strings. Some strings are reserved, for
example the ICC profile for an image is known by convention as
"icc-profile-data".</p>
<p>If you save an image in VIPS format, all metadata (with a restriction, see
below) is automatically saved for you in a block of XML at the end of the
file. When you load a VIPS image, the metadata is restored. You can use the
<code class="literal">vipsedit</code> command-line tool to extract or replace this block of XML.</p>
<p>VIPS metadata is based on <code class="literal">GValue</code>. See the docs for that system if you want
to do fancy stuff such as defining a new metadata type.
VIPS defines a new <code class="literal">GValue</code> called <code class="literal">vips_save_string</code>, a variety of string,
see <a class="link" href="libvips-type.html#vips-value-set-save-string" title="vips_value_set_save_string ()"><code class="function">vips_value_set_save_string()</code></a>.
If your <code class="literal">GValue</code> can be transformed to <code class="literal">vips_save_string</code>, it will be
saved and loaded to and from VIPS files for you.</p>
<p>VIPS provides a couple of base classes which implement
reference-counted areas of memory. If you base your metadata on one of
these types, it can be copied between images efficiently.</p>
</div>
<div class="refsect1">
<a name="libvips-header.functions_details"></a><h2>Functions</h2>
<div class="refsect2">
<a name="vips-format-sizeof"></a><h3>vips_format_sizeof ()</h3>
<pre class="programlisting"><span class="returnvalue">guint64</span>
vips_format_sizeof (<em class="parameter"><code><a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="type">VipsBandFormat</span></a> format</code></em>);</pre>
<div class="refsect3">
<a name="vips-format-sizeof.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>format</p></td>
<td class="parameter_description"><p>format type</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-format-sizeof.returns"></a><h4>Returns</h4>
<p> number of bytes for a band format.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-format-sizeof-unsafe"></a><h3>vips_format_sizeof_unsafe ()</h3>
<pre class="programlisting"><span class="returnvalue">guint64</span>
vips_format_sizeof_unsafe (<em class="parameter"><code><a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="type">VipsBandFormat</span></a> format</code></em>);</pre>
<p>A fast but dangerous version of <a class="link" href="libvips-header.html#vips-format-sizeof" title="vips_format_sizeof ()"><code class="function">vips_format_sizeof()</code></a>. You must have
previously range-checked <em class="parameter"><code>format</code></em>
or you'll crash.</p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
<div class="refsect3">
<a name="vips-format-sizeof-unsafe.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>format</p></td>
<td class="parameter_description"><p>format type</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-format-sizeof-unsafe.returns"></a><h4>Returns</h4>
<p> number of bytes for a band format.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-width"></a><h3>vips_image_get_width ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_width (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-width.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-width.returns"></a><h4>Returns</h4>
<p> the number of pixels across the image.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-height"></a><h3>vips_image_get_height ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_height (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-height.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-height.returns"></a><h4>Returns</h4>
<p> the number of pixels down the image.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-bands"></a><h3>vips_image_get_bands ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_bands (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-bands.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-bands.returns"></a><h4>Returns</h4>
<p> the number of bands (channels) in the image.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-format"></a><h3>vips_image_get_format ()</h3>
<pre class="programlisting"><a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="returnvalue">VipsBandFormat</span></a>
vips_image_get_format (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-format.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-format.returns"></a><h4>Returns</h4>
<p> the format of each band element.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-guess-format"></a><h3>vips_image_guess_format ()</h3>
<pre class="programlisting"><a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="returnvalue">VipsBandFormat</span></a>
vips_image_guess_format (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Return the <a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="type">VipsBandFormat</span></a> for an image, guessing a sane value if
the set value looks crazy.</p>
<p>For example, for a float image tagged as rgb16, we'd return ushort.</p>
<div class="refsect3">
<a name="vips-image-guess-format.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to guess for</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-guess-format.returns"></a><h4>Returns</h4>
<p> a sensible <a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="type">VipsBandFormat</span></a> for the image.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-coding"></a><h3>vips_image_get_coding ()</h3>
<pre class="programlisting"><a class="link" href="VipsImage.html#VipsCoding" title="enum VipsCoding"><span class="returnvalue">VipsCoding</span></a>
vips_image_get_coding (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-coding.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-coding.returns"></a><h4>Returns</h4>
<p> the image coding</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-interpretation"></a><h3>vips_image_get_interpretation ()</h3>
<pre class="programlisting"><a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="returnvalue">VipsInterpretation</span></a>
vips_image_get_interpretation (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Return the <a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="type">VipsInterpretation</span></a> set in the image header.
Use <a class="link" href="libvips-header.html#vips-image-guess-interpretation" title="vips_image_guess_interpretation ()"><code class="function">vips_image_guess_interpretation()</code></a> if you want a sanity-checked value.</p>
<div class="refsect3">
<a name="vips-image-get-interpretation.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-interpretation.returns"></a><h4>Returns</h4>
<p> the <a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="type">VipsInterpretation</span></a> from the image header.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-guess-interpretation"></a><h3>vips_image_guess_interpretation ()</h3>
<pre class="programlisting"><a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="returnvalue">VipsInterpretation</span></a>
vips_image_guess_interpretation (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Return the <a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="type">VipsInterpretation</span></a> for an image, guessing a sane value if
the set value looks crazy.</p>
<div class="refsect3">
<a name="vips-image-guess-interpretation.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to guess for</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-guess-interpretation.returns"></a><h4>Returns</h4>
<p> a sensible <a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="type">VipsInterpretation</span></a> for the image.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-xres"></a><h3>vips_image_get_xres ()</h3>
<pre class="programlisting"><span class="returnvalue">double</span>
vips_image_get_xres (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-xres.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-xres.returns"></a><h4>Returns</h4>
<p> the horizontal image resolution in pixels per millimeter. </p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-yres"></a><h3>vips_image_get_yres ()</h3>
<pre class="programlisting"><span class="returnvalue">double</span>
vips_image_get_yres (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-yres.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-yres.returns"></a><h4>Returns</h4>
<p> the vertical image resolution in pixels per millimeter. </p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-xoffset"></a><h3>vips_image_get_xoffset ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_xoffset (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-xoffset.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-xoffset.returns"></a><h4>Returns</h4>
<p> the horizontal position of the image origin, in pixels.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-yoffset"></a><h3>vips_image_get_yoffset ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_yoffset (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-yoffset.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-yoffset.returns"></a><h4>Returns</h4>
<p> the vertical position of the image origin, in pixels.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-filename"></a><h3>vips_image_get_filename ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
vips_image_get_filename (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<div class="refsect3">
<a name="vips-image-get-filename.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-filename.returns"></a><h4>Returns</h4>
<p> the name of the file the image was loaded from. </p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-mode"></a><h3>vips_image_get_mode ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
vips_image_get_mode (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Image modes are things like <code class="literal">"t"</code>, meaning a memory buffer, and <code class="literal">"p"</code>
meaning a delayed computation.</p>
<div class="refsect3">
<a name="vips-image-get-mode.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-mode.returns"></a><h4>Returns</h4>
<p> the image mode.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-scale"></a><h3>vips_image_get_scale ()</h3>
<pre class="programlisting"><span class="returnvalue">double</span>
vips_image_get_scale (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Matrix images can have an optional <code class="literal">scale</code> field for use by integer
convolution.</p>
<div class="refsect3">
<a name="vips-image-get-scale.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-scale.returns"></a><h4>Returns</h4>
<p> the scale.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-offset"></a><h3>vips_image_get_offset ()</h3>
<pre class="programlisting"><span class="returnvalue">double</span>
vips_image_get_offset (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Matrix images can have an optional <code class="literal">offset</code> field for use by integer
convolution.</p>
<div class="refsect3">
<a name="vips-image-get-offset.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get from</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-offset.returns"></a><h4>Returns</h4>
<p> the offset.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-data"></a><h3>vips_image_get_data ()</h3>
<pre class="programlisting">const <span class="returnvalue">void</span> *
vips_image_get_data (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>Return a pointer to the image's pixel data, if possible. This can involve
allocating large amounts of memory and performing a long computation. Image
pixels are laid out in band-packed rows.</p>
<p>Since this function modifies <em class="parameter"><code>image</code></em>
, it is not threadsafe. Only call it on
images which you are sure have not been shared with another thread. </p>
<p>See also: <a class="link" href="VipsImage.html#vips-image-wio-input" title="vips_image_wio_input ()"><code class="function">vips_image_wio_input()</code></a>, <a class="link" href="VipsImage.html#vips-image-copy-memory" title="vips_image_copy_memory ()"><code class="function">vips_image_copy_memory()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-get-data.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get data for</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-data.returns"></a><h4>Returns</h4>
<p> a pointer to pixel data, if possible. </p>
<p><span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-init-fields"></a><h3>vips_image_init_fields ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_init_fields (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code><span class="type">int</span> xsize</code></em>,
<em class="parameter"><code><span class="type">int</span> ysize</code></em>,
<em class="parameter"><code><span class="type">int</span> bands</code></em>,
<em class="parameter"><code><a class="link" href="VipsImage.html#VipsBandFormat" title="enum VipsBandFormat"><span class="type">VipsBandFormat</span></a> format</code></em>,
<em class="parameter"><code><a class="link" href="VipsImage.html#VipsCoding" title="enum VipsCoding"><span class="type">VipsCoding</span></a> coding</code></em>,
<em class="parameter"><code><a class="link" href="VipsImage.html#VipsInterpretation" title="enum VipsInterpretation"><span class="type">VipsInterpretation</span></a> interpretation</code></em>,
<em class="parameter"><code><span class="type">double</span> xres</code></em>,
<em class="parameter"><code><span class="type">double</span> yres</code></em>);</pre>
<p>A convenience function to set the header fields after creating an image.
Normally you copy the fields from your input images with
<a class="link" href="libvips-generate.html#vips-image-pipelinev" title="vips_image_pipelinev ()"><code class="function">vips_image_pipelinev()</code></a> and then make
any adjustments you need, but if you are creating an image from scratch,
for example <a class="link" href="libvips-create.html#vips-black" title="vips_black ()"><code class="function">vips_black()</code></a> or <a class="link" href="VipsForeignSave.html#vips-jpegload" title="vips_jpegload ()"><code class="function">vips_jpegload()</code></a>, you do need to set all the
fields yourself.</p>
<p>See also: <a class="link" href="libvips-generate.html#vips-image-pipelinev" title="vips_image_pipelinev ()"><code class="function">vips_image_pipelinev()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-init-fields.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to init</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>xsize</p></td>
<td class="parameter_description"><p>image width</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>ysize</p></td>
<td class="parameter_description"><p>image height</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>bands</p></td>
<td class="parameter_description"><p>image bands</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>format</p></td>
<td class="parameter_description"><p>band format</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>coding</p></td>
<td class="parameter_description"><p>image coding</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>interpretation</p></td>
<td class="parameter_description"><p>image type</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>xres</p></td>
<td class="parameter_description"><p>horizontal resolution, pixels per millimetre</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>yres</p></td>
<td class="parameter_description"><p>vertical resolution, pixels per millimetre</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set"></a><h3>vips_image_set ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">GValue</span> *value</code></em>);</pre>
<p>Set a piece of metadata on <em class="parameter"><code>image</code></em>
. Any old metadata with that name is
destroyed. The <code class="literal">GValue</code> is copied into the image, so you need to unset the
value when you're done with it.</p>
<p>For example, to set an integer on an image (though you would use the
convenience function <a class="link" href="libvips-header.html#vips-image-set-int" title="vips_image_set_int ()"><code class="function">vips_image_set_int()</code></a> in practice), you would do:</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
2
3
4
5
6</pre></td>
<td class="listing_code"><pre class="programlisting">GValue value <span class="gtkdoc opt">= {</span> <span class="number">0</span> <span class="gtkdoc opt">};</span>
<span class="function">g_value_init</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">,</span> G_TYPE_INT<span class="gtkdoc opt">);</span>
<span class="function">g_value_set_int</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">,</span> <span class="number">42</span><span class="gtkdoc opt">);</span>
<span class="function"><a href="libvips-header.html#vips-image-set">vips_image_set</a></span> <span class="gtkdoc opt">(</span>image<span class="gtkdoc opt">,</span> field<span class="gtkdoc opt">, &</span>value<span class="gtkdoc opt">);</span>
<span class="function">g_value_unset</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">);</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p></p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-set.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to set the metadata on</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>the name to give the metadata</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>value</p></td>
<td class="parameter_description"><p>the <code class="literal">GValue</code> to copy into the image</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get"></a><h3>vips_image_get ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">GValue</span> *value_copy</code></em>);</pre>
<p>Fill <em class="parameter"><code>value_copy</code></em>
with a copy of the header field. <em class="parameter"><code>value_copy</code></em>
must be zeroed
but uninitialised.</p>
<p>This will return -1 and add a message to the error buffer if the field
does not exist. Use <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a> to test for the
existence of a field first if you are not certain it will be there.</p>
<p>For example, to read a double from an image (though of course you would use
<a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()"><code class="function">vips_image_get_double()</code></a> in practice):</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17</pre></td>
<td class="listing_code"><pre class="programlisting">GValue value <span class="gtkdoc opt">= {</span> <span class="number">0</span> <span class="gtkdoc opt">};</span>
<span class="gtkdoc kwb">double</span> d<span class="gtkdoc opt">;</span>
<span class="keyword">if</span> <span class="gtkdoc opt">(</span><span class="function"><a href="libvips-header.html#vips-image-get">vips_image_get</a></span> <span class="gtkdoc opt">(</span>image<span class="gtkdoc opt">,</span> field<span class="gtkdoc opt">, &</span>value<span class="gtkdoc opt">))</span>
<span class="keyword">return</span> <span class="gtkdoc opt">-</span><span class="number">1</span><span class="gtkdoc opt">;</span>
<span class="keyword">if</span> <span class="gtkdoc opt">(</span><span class="function">G_VALUE_TYPE</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">) !=</span> G_TYPE_DOUBLE<span class="gtkdoc opt">) {</span>
<span class="function"><a href="libvips-error.html#vips-error">vips_error</a></span><span class="gtkdoc opt">(</span> <span class="string">"mydomain"</span><span class="gtkdoc opt">,</span>
<span class="function">_</span><span class="gtkdoc opt">(</span><span class="string">"field</span> <span class="gtkdoc esc">\"</span><span class="string">%s</span><span class="gtkdoc esc">\"</span> <span class="string">is of type %s, not double"</span><span class="gtkdoc opt">),</span>
field<span class="gtkdoc opt">,</span>
<span class="function">g_type_name</span> <span class="gtkdoc opt">(</span><span class="function">G_VALUE_TYPE</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">)));</span>
<span class="function">g_value_unset</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">);</span>
<span class="keyword">return</span> <span class="gtkdoc opt">-</span><span class="number">1</span><span class="gtkdoc opt">;</span>
<span class="gtkdoc opt">}</span>
d <span class="gtkdoc opt">=</span> <span class="function">g_value_get_double</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">);</span>
<span class="function">g_value_unset</span> <span class="gtkdoc opt">(&</span>value<span class="gtkdoc opt">);</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p></p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()"><code class="function">vips_image_get_double()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-get.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the field from from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>the name to give the metadata</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>value_copy</p></td>
<td class="parameter_description"><p> the <code class="literal">GValue</code> is copied into this. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>][<acronym title="Out parameter, where caller must allocate storage."><span class="acronym">out caller-allocates</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise. </p>
<p><span class="annotation">[<acronym title="Exposed in C code, not necessarily available in other languages."><span class="acronym">skip</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-as-string"></a><h3>vips_image_get_as_string ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_as_string (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">char</span> **out</code></em>);</pre>
<p>Gets <em class="parameter"><code>out</code></em>
from <em class="parameter"><code>im</code></em>
under the name <em class="parameter"><code>field</code></em>
.
This function will read any field, returning it as a printable string.
You need to free the string with <code class="function">g_free()</code> when you are done with it.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-get-as-string.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the header field from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>field name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>out</p></td>
<td class="parameter_description"><p> return field value as string. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="Free data after the code is done."><span class="acronym">transfer full</span></acronym>]</span></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-as-string.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-typeof"></a><h3>vips_image_get_typeof ()</h3>
<pre class="programlisting"><span class="returnvalue">GType</span>
vips_image_get_typeof (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>);</pre>
<p>Read the <code class="literal">GType</code> for a header field. Returns zero if there is no
field of that name. </p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-get-typeof.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to test</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>the name to search for</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-typeof.returns"></a><h4>Returns</h4>
<p> the <code class="literal">GType</code> of the field, or zero if there is no
field of that name.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-remove"></a><h3>vips_image_remove ()</h3>
<pre class="programlisting"><span class="returnvalue">gboolean</span>
vips_image_remove (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>);</pre>
<p>Find and remove an item of metadata. Return <code class="literal">FALSE</code> if no metadata of that
name was found.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-remove.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to test</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>the name to search for</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-remove.returns"></a><h4>Returns</h4>
<p> <code class="literal">TRUE</code> if an item of metadata of that name was found and removed</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="VipsImageMapFn"></a><h3>VipsImageMapFn ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> *
<span class="c_punctuation">(</span>*VipsImageMapFn<span class="c_punctuation">)</span> (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">GValue</span> *value</code></em>,
<em class="parameter"><code><span class="type">void</span> *a</code></em>);</pre>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-map"></a><h3>vips_image_map ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span> *
vips_image_map (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code><a class="link" href="libvips-header.html#VipsImageMapFn" title="VipsImageMapFn ()"><span class="type">VipsImageMapFn</span></a> fn</code></em>,
<em class="parameter"><code><span class="type">void</span> *a</code></em>);</pre>
<p>This function calls <em class="parameter"><code>fn</code></em>
for every header field, including every item of
metadata. </p>
<p>Like all _map functions, the user function should return <code class="literal">NULL</code> to continue
iteration, or a non-<code class="literal">NULL</code> pointer to indicate early termination.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a>, <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-map.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to map over</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>fn</p></td>
<td class="parameter_description"><p> function to call for each header field. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid only during the call to the method."><span class="acronym">scope call</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>a</p></td>
<td class="parameter_description"><p>user data for function</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-map.returns"></a><h4>Returns</h4>
<p> <code class="literal">NULL</code> on success, the failing pointer otherwise. </p>
<p><span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span></p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set-area"></a><h3>vips_image_set_area ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set_area (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><a class="link" href="libvips-basic.html#VipsCallbackFn" title="VipsCallbackFn ()"><span class="type">VipsCallbackFn</span></a> free_fn</code></em>,
<em class="parameter"><code><span class="type">void</span> *data</code></em>);</pre>
<p>Attaches <em class="parameter"><code>data</code></em>
as a metadata item on <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
. When
VIPS no longer needs the metadata, it will be freed with <em class="parameter"><code>free_fn</code></em>
.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()"><code class="function">vips_image_get_double()</code></a>, <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a></p>
<div class="refsect3">
<a name="vips-image-set-area.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach the metadata to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>free_fn</p></td>
<td class="parameter_description"><p> free function for <em class="parameter"><code>data</code></em>
. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid until first called."><span class="acronym">scope async</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>pointer to area of memory</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-area"></a><h3>vips_image_get_area ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_area (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">void</span> **data</code></em>);</pre>
<p>Gets <em class="parameter"><code>data</code></em>
from <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
. A convenience
function over <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>. Use <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a> to test for
the existance of a piece of metadata.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-set-area" title="vips_image_set_area ()"><code class="function">vips_image_set_area()</code></a>, <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>,
<a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a></p>
<div class="refsect3">
<a name="vips-image-get-area.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the metadata from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>return metadata value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-area.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set-blob"></a><h3>vips_image_set_blob ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set_blob (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><a class="link" href="libvips-basic.html#VipsCallbackFn" title="VipsCallbackFn ()"><span class="type">VipsCallbackFn</span></a> free_fn</code></em>,
<em class="parameter"><code><span class="type">void</span> *data</code></em>,
<em class="parameter"><code><span class="type">size_t</span> length</code></em>);</pre>
<p>Attaches <em class="parameter"><code>blob</code></em>
as a metadata item on <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
. A
convenience
function over <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a> using an vips_blob.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-blob" title="vips_image_get_blob ()"><code class="function">vips_image_get_blob()</code></a>, <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-set-blob.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach the metadata to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>free_fn</p></td>
<td class="parameter_description"><p> free function for <em class="parameter"><code>data</code></em>
. </p></td>
<td class="parameter_annotations"><span class="annotation">[<acronym title="The callback is valid until first called."><span class="acronym">scope async</span></acronym>]</span></td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>pointer to area of memory</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>length</p></td>
<td class="parameter_description"><p>length of memory area</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-blob"></a><h3>vips_image_get_blob ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_blob (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">void</span> **data</code></em>,
<em class="parameter"><code><span class="type">size_t</span> *length</code></em>);</pre>
<p>Gets <em class="parameter"><code>blob</code></em>
from <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
, optionally return its length in
<em class="parameter"><code>length</code></em>
. A convenience
function over <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>. Use <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a> to test for the
existance
of a piece of metadata.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a>, <a class="link" href="libvips-type.html#vips-blob-get" title="vips_blob_get ()"><code class="function">vips_blob_get()</code></a>,</p>
<div class="refsect3">
<a name="vips-image-get-blob.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the metadata from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>data</p></td>
<td class="parameter_description"><p>pointer to area of memory</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>length</p></td>
<td class="parameter_description"><p>return the blob length here, optionally</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-blob.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-int"></a><h3>vips_image_get_int ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_int (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">int</span> *out</code></em>);</pre>
<p>Gets <em class="parameter"><code>out</code></em>
from <em class="parameter"><code>im</code></em>
under the name <em class="parameter"><code>field</code></em>
. This function searches for
int-valued fields.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a></p>
<div class="refsect3">
<a name="vips-image-get-int.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the header field from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>field name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>out</p></td>
<td class="parameter_description"><p>return field value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-int.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set-int"></a><h3>vips_image_set_int ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set_int (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">int</span> i</code></em>);</pre>
<p>Attaches <em class="parameter"><code>i</code></em>
as a metadata item on <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
. A
convenience
function over <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a>.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-int" title="vips_image_get_int ()"><code class="function">vips_image_get_int()</code></a>, <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a></p>
<div class="refsect3">
<a name="vips-image-set-int.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach the metadata to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>i</p></td>
<td class="parameter_description"><p>metadata value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-double"></a><h3>vips_image_get_double ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_double (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">double</span> *out</code></em>);</pre>
<p>Gets <em class="parameter"><code>out</code></em>
from <em class="parameter"><code>im</code></em>
under the name <em class="parameter"><code>field</code></em>
.
This function searches for
double-valued fields.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a></p>
<div class="refsect3">
<a name="vips-image-get-double.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the header field from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>field name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>out</p></td>
<td class="parameter_description"><p>return field value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-double.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set-double"></a><h3>vips_image_set_double ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set_double (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code><span class="type">double</span> d</code></em>);</pre>
<p>Attaches <em class="parameter"><code>d</code></em>
as a metadata item on <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
. A
convenience
function over <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a>.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()"><code class="function">vips_image_get_double()</code></a>, <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a></p>
<div class="refsect3">
<a name="vips-image-set-double.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach the metadata to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>d</p></td>
<td class="parameter_description"><p>metadata value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-string"></a><h3>vips_image_get_string ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_get_string (<em class="parameter"><code>const <a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code>const <span class="type">char</span> **out</code></em>);</pre>
<p>Gets <em class="parameter"><code>out</code></em>
from <em class="parameter"><code>im</code></em>
under the name <em class="parameter"><code>field</code></em>
.
This function searches for string-valued fields. </p>
<p>Do not free <em class="parameter"><code>out</code></em>
.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get" title="vips_image_get ()"><code class="function">vips_image_get()</code></a>, <a class="link" href="libvips-header.html#vips-image-get-typeof" title="vips_image_get_typeof ()"><code class="function">vips_image_get_typeof()</code></a></p>
<div class="refsect3">
<a name="vips-image-get-string.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to get the header field from</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>field name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>out</p></td>
<td class="parameter_description"><p>return field value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-string.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 otherwise.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-set-string"></a><h3>vips_image_set_string ()</h3>
<pre class="programlisting"><span class="returnvalue">void</span>
vips_image_set_string (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *field</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *str</code></em>);</pre>
<p>Attaches <em class="parameter"><code>str</code></em>
as a metadata item on <em class="parameter"><code>image</code></em>
under the name <em class="parameter"><code>field</code></em>
.
A convenience
function over <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a> using an vips_ref_string.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-double" title="vips_image_get_double ()"><code class="function">vips_image_get_double()</code></a>, <a class="link" href="libvips-header.html#vips-image-set" title="vips_image_set ()"><code class="function">vips_image_set()</code></a>, vips_ref_string</p>
<div class="refsect3">
<a name="vips-image-set-string.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach the metadata to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>field</p></td>
<td class="parameter_description"><p>metadata name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>str</p></td>
<td class="parameter_description"><p>metadata value</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-history-printf"></a><h3>vips_image_history_printf ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_history_printf (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *format</code></em>,
<em class="parameter"><code>...</code></em>);</pre>
<p>Add a line to the image history. The <em class="parameter"><code>format</code></em>
and arguments are expanded, the
date and time is appended prefixed with a hash character, and the whole
string is appended to the image history and terminated with a newline.</p>
<p>For example:</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
2</pre></td>
<td class="listing_code"><pre class="programlisting"><span class="function"><a href="libvips-header.html#vips-image-history-printf">vips_image_history_printf</a></span> <span class="gtkdoc opt">(</span>image<span class="gtkdoc opt">,</span> <span class="string">"vips invert %s %s"</span><span class="gtkdoc opt">,</span>
in<span class="gtkdoc opt">-></span>filename<span class="gtkdoc opt">,</span> out<span class="gtkdoc opt">-></span>filename<span class="gtkdoc opt">);</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p></p>
<p>Might add the string</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1</pre></td>
<td class="listing_code"><pre class="programlisting"><span class="string">"vips invert /home/john/fred.v /home/john/jim.v # Fri Apr 3 23:30:35 2009</span><span class="gtkdoc esc">\n</span><span class="string">"</span></pre></td>
</tr>
</tbody>
</table>
</div>
<p></p>
<p>VIPS operations don't add history lines for you because a single action at
the application level might involve many VIPS operations. History must be
recorded by the application.</p>
<div class="refsect3">
<a name="vips-image-history-printf.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>add history line to this image</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>format</p></td>
<td class="parameter_description"><p>printf() format string</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>...</p></td>
<td class="parameter_description"><p>arguments to format string</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-history-printf.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 on error.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-history-args"></a><h3>vips_image_history_args ()</h3>
<pre class="programlisting"><span class="returnvalue">int</span>
vips_image_history_args (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>,
<em class="parameter"><code>const <span class="type">char</span> *name</code></em>,
<em class="parameter"><code><span class="type">int</span> argc</code></em>,
<em class="parameter"><code><span class="type">char</span> *argv[]</code></em>);</pre>
<p>Formats the name/argv as a single string and calls
<a class="link" href="libvips-header.html#vips-image-history-printf" title="vips_image_history_printf ()"><code class="function">vips_image_history_printf()</code></a>. A
convenience function for command-line prorams.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-get-history" title="vips_image_get_history ()"><code class="function">vips_image_get_history()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-history-args.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody>
<tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>image to attach history line to</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>name</p></td>
<td class="parameter_description"><p>program name</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>argc</p></td>
<td class="parameter_description"><p>number of program arguments</p></td>
<td class="parameter_annotations"> </td>
</tr>
<tr>
<td class="parameter_name"><p>argv</p></td>
<td class="parameter_description"><p>program arguments</p></td>
<td class="parameter_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-history-args.returns"></a><h4>Returns</h4>
<p> 0 on success, -1 on error.</p>
</div>
</div>
<hr>
<div class="refsect2">
<a name="vips-image-get-history"></a><h3>vips_image_get_history ()</h3>
<pre class="programlisting">const <span class="returnvalue">char</span> *
vips_image_get_history (<em class="parameter"><code><a class="link" href="VipsImage.html" title="VipsImage"><span class="type">VipsImage</span></a> *image</code></em>);</pre>
<p>This function reads the image history as a C string. The string is owned
by VIPS and must not be freed.</p>
<p>VIPS tracks the history of each image, that is, the sequence of operations
that generated that image. Applications built on VIPS need to call
<a class="link" href="libvips-header.html#vips-image-history-printf" title="vips_image_history_printf ()"><code class="function">vips_image_history_printf()</code></a> for each action they perform, setting the
command-line equivalent for the action.</p>
<p>See also: <a class="link" href="libvips-header.html#vips-image-history-printf" title="vips_image_history_printf ()"><code class="function">vips_image_history_printf()</code></a>.</p>
<div class="refsect3">
<a name="vips-image-get-history.parameters"></a><h4>Parameters</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="parameters_name">
<col class="parameters_description">
<col width="200px" class="parameters_annotations">
</colgroup>
<tbody><tr>
<td class="parameter_name"><p>image</p></td>
<td class="parameter_description"><p>get history from here</p></td>
<td class="parameter_annotations"> </td>
</tr></tbody>
</table></div>
</div>
<div class="refsect3">
<a name="vips-image-get-history.returns"></a><h4>Returns</h4>
<p> The history of <em class="parameter"><code>image</code></em>
as a C string. Do not free!. </p>
<p><span class="annotation">[<acronym title="Don't free data after the code is done."><span class="acronym">transfer none</span></acronym>]</span></p>
</div>
</div>
</div>
<div class="refsect1">
<a name="libvips-header.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="VIPS-META-EXIF-NAME:CAPS"></a><h3>VIPS_META_EXIF_NAME</h3>
<pre class="programlisting">#define VIPS_META_EXIF_NAME "exif-data"
</pre>
<p>The name that JPEG read and write operations use for the image's EXIF data.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-XMP-NAME:CAPS"></a><h3>VIPS_META_XMP_NAME</h3>
<pre class="programlisting">#define VIPS_META_XMP_NAME "xmp-data"
</pre>
<p>The name that read and write operations use for the image's XMP data.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-IPCT-NAME:CAPS"></a><h3>VIPS_META_IPCT_NAME</h3>
<pre class="programlisting">#define VIPS_META_IPCT_NAME "ipct-data"
</pre>
<p>The name that read and write operations use for the image's IPCT data.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-PHOTOSHOP-NAME:CAPS"></a><h3>VIPS_META_PHOTOSHOP_NAME</h3>
<pre class="programlisting">#define VIPS_META_PHOTOSHOP_NAME "photoshop-data"
</pre>
<p>The name that TIFF read and write operations use for the image's
TIFFTAG_PHOTOSHOP data.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-ICC-NAME:CAPS"></a><h3>VIPS_META_ICC_NAME</h3>
<pre class="programlisting">#define VIPS_META_ICC_NAME "icc-profile-data"
</pre>
<p>The name we use to attach an ICC profile. The file read and write
operations for TIFF, JPEG, PNG and others use this item of metadata to
attach and save ICC profiles. The profile is updated by the
<a class="link" href="libvips-colour.html#vips-icc-transform" title="vips_icc_transform ()"><code class="function">vips_icc_transform()</code></a> operations.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-XML:CAPS"></a><h3>VIPS_META_XML</h3>
<pre class="programlisting">#define VIPS_META_XML "xml-header"
</pre>
<p>The original XML that was used to code the metadata after reading a VIPS
format file.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-IMAGEDESCRIPTION:CAPS"></a><h3>VIPS_META_IMAGEDESCRIPTION</h3>
<pre class="programlisting">#define VIPS_META_IMAGEDESCRIPTION "image-description"
</pre>
<p>The IMAGEDESCRIPTION tag. Often has useful metadata.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-RESOLUTION-UNIT:CAPS"></a><h3>VIPS_META_RESOLUTION_UNIT</h3>
<pre class="programlisting">#define VIPS_META_RESOLUTION_UNIT "resolution-unit"
</pre>
<p>The JPEG and TIFF read and write operations use this to record the
file's preferred unit for resolution.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-LOADER:CAPS"></a><h3>VIPS_META_LOADER</h3>
<pre class="programlisting">#define VIPS_META_LOADER "vips-loader"
</pre>
<p>Record the name of the original loader here. Handy for hinting file formats
and for debugging.</p>
</div>
<hr>
<div class="refsect2">
<a name="VIPS-META-ORIENTATION:CAPS"></a><h3>VIPS_META_ORIENTATION</h3>
<pre class="programlisting">#define VIPS_META_ORIENTATION "orientation"
</pre>
<p>The orientation tag for this image. An int from 1 - 8 using the standard
exif/tiff meanings. </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>1 - The 0th row represents the visual top of the image, and the 0th column
represents the visual left-hand side.</p></li>
<li class="listitem"><p>2 - The 0th row represents the visual top of the image, and the 0th column
represents the visual right-hand side.</p></li>
<li class="listitem"><p>3 - The 0th row represents the visual bottom of the image, and the 0th
column represents the visual right-hand side.</p></li>
<li class="listitem"><p>4 - The 0th row represents the visual bottom of the image, and the 0th
column represents the visual left-hand side.</p></li>
<li class="listitem"><p>5 - The 0th row represents the visual left-hand side of the image, and the
0th column represents the visual top.</p></li>
<li class="listitem"><p>6 - The 0th row represents the visual right-hand side of the image, and the
0th column represents the visual top.</p></li>
<li class="listitem"><p>7 - The 0th row represents the visual right-hand side of the image, and the
0th column represents the visual bottom.</p></li>
<li class="listitem"><p>8 - The 0th row represents the visual left-hand side of the image, and the
0th column represents the visual bottom.</p></li>
</ul></div>
</div>
</div>
<div class="refsect1">
<a name="libvips-header.see-also"></a><h2>See Also</h2>
<a class="link" href="libvips-type.html" title="type">type</a>
</div>
</div>
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