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<h2 id="GridGeometry">Grid coverage domain</h2>
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<p>
The domain of a coverage is the set of valid input values.
In Apache <abbr>SIS</abbr>, the domain of grid coverages is described by the <code>GridGeometry</code> class.
This class contains the following information:
</p>
<ul>
<li>A grid extent (a.k.a. <dfn>grid envelope</dfn>), often inferred from the image size in pixels.</li>
<li>A <dfn>grid to <abbr>CRS</abbr></dfn> conversion, typically as a scale followed by a translation.</li>
<li>A georeferenced envelope, which can be inferred from the grid extent and the <dfn>grid to <abbr>CRS</abbr></dfn> conversion.</li>
<li>A Coordinate Reference System (<abbr>CRS</abbr>) which is the target of the <dfn>grid to CRS</dfn> conversion.</li>
<li>An <em>estimation</em> of grid resolution along each <abbr>CRS</abbr> axes.</li>
<li>An indication of whether conversion for some axes is linear or not.</li>
</ul>
<p>
One of the most important property listed above is the <dfn>grid to <abbr>CRS</abbr></dfn> conversion,
which defines how to map pixel coordinates to "real world" coordinates such as latitudes and longitudes.
This relationship is often linear (an affine transform), but not necessarily;
<code>GridGeometry</code> accepts non-linear conversions as well.
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