dip-ImageIterator-T.html

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        <h1>
          <div class="m-doc-include m-thin m-right-m m-text-right">
<a href="iterators.html" class="m-doc">Iterators</a> module<br/><span class="m-code m-thin">#include <a href="file--diplib--iterators-h.html">"diplib/iterators.h"</a></span>          </div>

          <div class="m-doc-template"><span class="m-doc-wrap-bumper">template&lt;</span><span class="m-doc-wrap">typename T&gt;</span></div>
          <span class="m-breadcrumb"><a href="dip.html">dip</a>::<wbr/></span>ImageIterator <span class="m-thin">class</span>        </h1>
        <p>An iterator to iterate over all pixels of an image, or all lines of an image.</p>
        <div class="m-block m-default">
          <h3>Contents</h3>
          <ul>
            <li>
              Reference
              <ul>
                <li><a href="#typeless-methods">Constructors, destructors, assignment and conversion operators</a></li>
                <li><a href="#alias-members">Aliases</a></li>
                <li><a href="#function-members">Functions</a></li>
                <li><a href="#operator-members">Operators</a></li>
                <li><a href="#related">Related</a></li>
              </ul>
            </li>
          </ul>
        </div>
          <p>If it is created with the processing dimension set, then the processing dimension indicates
a dimension over which this iterator does not iterate. That is, it will iterate over all pixels
that have a coordinate equal to 0 along this dimension. In this case, a <a href="dip-LineIterator-T.html"><code>dip::LineIterator</code></a>
can be obtained to iterate over the line that starts at the current pixel (using the
<code>GetLineIterator</code> method).</p>
<p>If the processing dimension is not set, then the iterator visits all pixels in the image.</p>
<p>The iterator can be incremented until it reaches the end of the image. At this point, the
iterator will become invalid. An invalid iterator will test false. The <code>IsAtEnd</code> method
can be used instead to test for this condition. It is also possible to compare two iterators
for equality (i.e. to compare against an end iterator).</p>
<p>Dereferencing the iterator yields the first sample of the current pixel (<code>*it</code> == <code>it[ 0 ]</code>).
One can index using the <code>[]</code> operator to obtain each of the samples of the tensor
(<code>it[ 0 ]</code> .. <code>it[ image.TensorElements() - 1 ]</code>).</p>
<p>Alternatively, a <a href="dip-SampleIterator-T.html"><code>dip::SampleIterator</code></a> can be obtained to iterate over the samples of the tensor
(<code>it.begin()</code> .. <code>it.end()</code>).</p>
<p>It is possible to obtain neighboring pixel values by adding the neighbor&rsquo;s offset to the current
pointer:</p>
<div class="m-code"><pre><span></span><span class="o">*</span><span class="p">(</span><span class="w"> </span><span class="n">it</span><span class="p">.</span><span class="n">Pointer</span><span class="p">()</span><span class="w"> </span><span class="o">+</span><span class="w"> </span><span class="n">offset</span><span class="w"> </span><span class="p">)</span>
</pre></div>

<p>Note that this offset can cause a read-out-of-bounds or simply access the wrong pixel if the neighbor
is not within the image domain. One would have to test for <code>it.Coordinates()</code> to be far enough away
from the edge of the image. The most optimal way to access neighbors is to iterate over a window
within a larger image, such that one can be sure that neighbors always exist. See <a href="boundary.html#dip-ExtendImage-Image-CL-Image-L-UnsignedArray--BoundaryConditionArray--Option-ExtendImageFlags-"><code>dip::ExtendImage</code></a>.</p>
<p>By default, the iterator loops over pixels (or image lines) in linear index order. That is, coordinates
change as: {0,0}, {1,0}, {2,0}, &hellip; {0,1}, {1,1}, &hellip; If the image does not have normal strides, this
is not the most efficient way of looping over all pixels. The method <code>Optimize</code> changes the order in
which pixels are accessed to be the order in which they are stored in memory. After calling <code>Optimize</code>,
the output of <code>Coordinates</code> and <code>Index</code> no longer match the input image.</p>
<p>Satisfies all the requirements for a mutable <a href="http://en.cppreference.com/w/cpp/iterator">ForwardIterator</a>.</p>
<p>Note that when an image is stripped or reforged, all its iterators are invalidated.</p>
<aside class="m-note m-default">
<h4>See also</h4>
<p><a href="using_iterators.html">Using iterators to implement filters</a>, <a href="dip-JointImageIterator-T.html"><code>dip::JointImageIterator</code></a>, <a href="dip-LineIterator-T.html"><code>dip::LineIterator</code></a>, <a href="dip-SampleIterator-T.html"><code>dip::SampleIterator</code></a>, <a href="dip-GenericImageIterator-T.html"><code>dip::GenericImageIterator</code></a></p>
</aside>
        <section id="typeless-methods">
            <h2>Constructors, destructors, assignment and conversion operators</h2>
            <dl class="m-doc">
                              <dt id="dip-ImageIterator-T-ImageIterator">
              <span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-ImageIterator" class="m-doc-self">ImageIterator</a>(</span><span class="m-doc-wrap">)</span>
            </dt>
            <dd>Default constructor yields an invalid iterator that cannot be dereferenced, and is equivalent to an end iterator</dd>
                              <dt id="dip-ImageIterator-T-ImageIterator-Image-CL-dip-uint-">
              <span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-ImageIterator-Image-CL-dip-uint-" class="m-doc-self">ImageIterator</a>(</span><span class="m-doc-wrap"><a href="dip-Image.html" class="m-doc">dip::Image</a> const&amp; image,
              <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a> procDim = std::numeric_limits<dip::uint>::max()) <span class="m-label m-flat m-info">explicit</span> </span>
            </dt>
            <dd>To construct a useful iterator, provide an image and optionally a processing dimension</dd>
                              <dt>
              <span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-ImageIterator-Image-CL-UnsignedArray-CL-UnsignedArray--UnsignedArray-CL-dip-uint-" class="m-doc">ImageIterator</a>(</span><span class="m-doc-wrap"><a href="dip-Image.html" class="m-doc">dip::Image</a> const&amp; image,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp; origin,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> sizes,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp; spacing = {},
              <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a> procDim = std::numeric_limits<dip::uint>::max())</span>
            </dt>
            <dd>To construct a useful iterator, provide an image, an ROI, and optionally a processing dimension. <a href="#dip-ImageIterator-T-ImageIterator-Image-CL-UnsignedArray-CL-UnsignedArray--UnsignedArray-CL-dip-uint-">more...</a></dd>
            </dl>
        </section>
        <section id="alias-members">
            <h2>Aliases</h2>
            <dl class="m-doc">
                              <dt id="dip-ImageIterator-T-iterator_category">
              using <a href="#dip-ImageIterator-T-iterator_category" class="m-doc-self">iterator_category</a> = std::forward_iterator_tag

            </dt>
            <dd>Iterator category</dd>
                              <dt id="dip-ImageIterator-T-value_type">
              using <a href="#dip-ImageIterator-T-value_type" class="m-doc-self">value_type</a> = T

            </dt>
            <dd>The data type of the sample, obtained when dereferencing the iterator</dd>
                              <dt id="dip-ImageIterator-T-reference">
              using <a href="#dip-ImageIterator-T-reference" class="m-doc-self">reference</a> = T&amp;

            </dt>
            <dd>The type of a reference to a sample</dd>
                              <dt id="dip-ImageIterator-T-pointer">
              using <a href="#dip-ImageIterator-T-pointer" class="m-doc-self">pointer</a> = T*

            </dt>
            <dd>The type of a pointer to a pixel</dd>
            </dl>
        </section>
        <section id="function-members">
          <h2>Functions</h2>
          <dl class="m-doc">
                          <dt id="dip-ImageIterator-T-swap-ImageIterator<T>-L">
              <span class="m-doc-wrap-bumper">void <a href="#dip-ImageIterator-T-swap-ImageIterator<T>-L" class="m-doc-self">swap</a>(</span><span class="m-doc-wrap"><a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp; other) <span class="m-label m-flat m-success">noexcept</span></span>
            </dt>
            <dd>Swap</dd>
                          <dt id="dip-ImageIterator-T-begin-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-begin-C" class="m-doc-self">begin</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-SampleIterator-T.html" class="m-doc">dip::SampleIterator</a></span>
            </dt>
            <dd>Get an iterator over the tensor for the current pixel</dd>
                          <dt id="dip-ImageIterator-T-end-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-end-C" class="m-doc-self">end</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-SampleIterator-T.html" class="m-doc">dip::SampleIterator</a></span>
            </dt>
            <dd>Get an end iterator over the tensor for the current pixel</dd>
                          <dt id="dip-ImageIterator-T-cbegin-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-cbegin-C" class="m-doc-self">cbegin</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-SampleIterator-T.html#dip-ConstSampleIterator-T" class="m-doc">dip::ConstSampleIterator</a></span>
            </dt>
            <dd>Get a const iterator over the tensor for the current pixel</dd>
                          <dt id="dip-ImageIterator-T-cend-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-cend-C" class="m-doc-self">cend</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-SampleIterator-T.html#dip-ConstSampleIterator-T" class="m-doc">dip::ConstSampleIterator</a></span>
            </dt>
            <dd>Get an end const iterator over the tensor for the current pixel</dd>
                          <dt id="dip-ImageIterator-T-GetLineIterator-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-GetLineIterator-C" class="m-doc-self">GetLineIterator</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-LineIterator-T.html" class="m-doc">dip::LineIterator</a></span>
            </dt>
            <dd>Get an iterator over the current line</dd>
                          <dt id="dip-ImageIterator-T-GetConstLineIterator-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-GetConstLineIterator-C" class="m-doc-self">GetConstLineIterator</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-LineIterator-T.html#dip-ConstLineIterator-T" class="m-doc">dip::ConstLineIterator</a></span>
            </dt>
            <dd>Get a const iterator over the current line</dd>
                          <dt id="dip-ImageIterator-T-IsAtEnd-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-IsAtEnd-C" class="m-doc-self">IsAtEnd</a>(</span><span class="m-doc-wrap">) const -&gt; bool</span>
            </dt>
            <dd>Test to see if the iterator reached past the last pixel</dd>
                          <dt id="dip-ImageIterator-T-Coordinates-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Coordinates-C" class="m-doc-self">Coordinates</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp;</span>
            </dt>
            <dd>Return the current coordinates</dd>
                          <dt id="dip-ImageIterator-T-SetCoordinates-UnsignedArray-">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-SetCoordinates-UnsignedArray-" class="m-doc-self">SetCoordinates</a>(</span><span class="m-doc-wrap"><a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> coords) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;</span>
            </dt>
            <dd>Set the iterator to point at a different location in the image</dd>
                          <dt id="dip-ImageIterator-T-Sizes-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Sizes-C" class="m-doc-self">Sizes</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp;</span>
            </dt>
            <dd>Return the sizes of the image we&rsquo;re iterating over.</dd>
                          <dt id="dip-ImageIterator-T-ProcessingDimensionSize-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-ProcessingDimensionSize-C" class="m-doc-self">ProcessingDimensionSize</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a></span>
            </dt>
            <dd>Return the size along the processing dimension</dd>
                          <dt id="dip-ImageIterator-T-Strides-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Strides-C" class="m-doc-self">Strides</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-IntegerArray" class="m-doc">dip::IntegerArray</a> const&amp;</span>
            </dt>
            <dd>Return the strides used to iterate over the image.</dd>
                          <dt id="dip-ImageIterator-T-ProcessingDimensionStride-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-ProcessingDimensionStride-C" class="m-doc-self">ProcessingDimensionStride</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-sint" class="m-doc">dip::sint</a></span>
            </dt>
            <dd>Return the stride along the processing dimension</dd>
                          <dt>
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-IsOnEdge-C" class="m-doc">IsOnEdge</a>(</span><span class="m-doc-wrap">) const -&gt; bool</span>
            </dt>
            <dd>Return true if the iterator points at a pixel on the edge of the image. <a href="#dip-ImageIterator-T-IsOnEdge-C">more...</a></dd>
                          <dt id="dip-ImageIterator-T-Pointer-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Pointer-C" class="m-doc-self">Pointer</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-ImageIterator-T.html#dip-ImageIterator-T-pointer" class="m-doc">dip::ImageIterator::pointer</a></span>
            </dt>
            <dd>Return the current pointer</dd>
                          <dt id="dip-ImageIterator-T-Offset-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Offset-C" class="m-doc-self">Offset</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-sint" class="m-doc">dip::sint</a></span>
            </dt>
            <dd>Return the current offset</dd>
                          <dt id="dip-ImageIterator-T-Index-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Index-C" class="m-doc-self">Index</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a></span>
            </dt>
            <dd>Return the current index, which is computed: this function is not trivial</dd>
                          <dt id="dip-ImageIterator-T-HasProcessingDimension-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-HasProcessingDimension-C" class="m-doc-self">HasProcessingDimension</a>(</span><span class="m-doc-wrap">) const -&gt; bool</span>
            </dt>
            <dd>True if the processing dimension is set</dd>
                          <dt>
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-ProcessingDimension-C" class="m-doc">ProcessingDimension</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a></span>
            </dt>
            <dd>Return the processing dimension, the direction of the lines over which the iterator iterates. <a href="#dip-ImageIterator-T-ProcessingDimension-C">more...</a></dd>
                          <dt id="dip-ImageIterator-T-Reset">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Reset" class="m-doc-self">Reset</a>(</span><span class="m-doc-wrap">) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;</span>
            </dt>
            <dd>Reset the iterator to the first pixel in the image (as it was when first created)</dd>
                          <dt>
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-Optimize" class="m-doc">Optimize</a>(</span><span class="m-doc-wrap">) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;</span>
            </dt>
            <dd>Optimizes the order in which the iterator visits the image pixels. <a href="#dip-ImageIterator-T-Optimize">more...</a></dd>
                          <dt id="dip-ImageIterator-T-OptimizeAndFlatten">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-OptimizeAndFlatten" class="m-doc-self">OptimizeAndFlatten</a>(</span><span class="m-doc-wrap">) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;</span>
            </dt>
            <dd>Like <code>Optimize</code>, but additionally folds dimensions together where possible (flattens the image,
so that the iterator has fewer dimensions to work with). The processing dimension is not affected.</dd>
          </dl>
        </section>
        <section id="operator-members">
          <h2>Operators</h2>
          <dl class="m-doc">
                          <dt id="dip-ImageIterator-T-operator%2A-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%2A-C" class="m-doc-self">operator*</a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-ImageIterator-T.html#dip-ImageIterator-T-reference" class="m-doc">dip::ImageIterator::reference</a></span>
            </dt>
            <dd>Dereference</dd>
                          <dt id="dip-ImageIterator-T-operator-%3E-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator-%3E-C" class="m-doc-self">operator-></a>(</span><span class="m-doc-wrap">) const -&gt; <a href="dip-ImageIterator-T.html#dip-ImageIterator-T-pointer" class="m-doc">dip::ImageIterator::pointer</a></span>
            </dt>
            <dd>Dereference</dd>
                          <dt id="dip-ImageIterator-T-operator%5B%5D-dip-uint--C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%5B%5D-dip-uint--C" class="m-doc-self">operator[]</a>(</span><span class="m-doc-wrap"><a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a> index) const -&gt; <a href="dip-ImageIterator-T.html#dip-ImageIterator-T-reference" class="m-doc">dip::ImageIterator::reference</a></span>
            </dt>
            <dd>Index into tensor, <code>it[0]</code> is equal to <code>*it</code>, but <code>it[1]</code> is not equal to <code>*(++it)</code>.</dd>
                          <dt id="dip-ImageIterator-T-operator%2B%2B">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%2B%2B" class="m-doc-self">operator++</a>(</span><span class="m-doc-wrap">) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;</span>
            </dt>
            <dd>Pre-increment</dd>
                          <dt id="dip-ImageIterator-T-operator%2B%2B-int-">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%2B%2B-int-" class="m-doc-self">operator++</a>(</span><span class="m-doc-wrap">int ) -&gt; <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a></span>
            </dt>
            <dd>Post-increment</dd>
                          <dt id="dip-ImageIterator-T-operator%3D%3D-ImageIterator<T>-CL-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%3D%3D-ImageIterator<T>-CL-C" class="m-doc-self">operator==</a>(</span><span class="m-doc-wrap"><a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a> const&amp; other) const -&gt; bool</span>
            </dt>
            <dd>Equality comparison</dd>
                          <dt id="dip-ImageIterator-T-operator%21%3D-ImageIterator<T>-CL-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%21%3D-ImageIterator<T>-CL-C" class="m-doc-self">operator!=</a>(</span><span class="m-doc-wrap"><a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a> const&amp; other) const -&gt; bool</span>
            </dt>
            <dd>Inequality comparison</dd>
                          <dt id="dip-ImageIterator-T-operator%20bool-C">
              <span class="m-doc-wrap-bumper">auto <a href="#dip-ImageIterator-T-operator%20bool-C" class="m-doc-self">operator bool</a>(</span><span class="m-doc-wrap">) const -&gt; bool <span class="m-label m-flat m-info">explicit</span> </span>
            </dt>
            <dd>Test to see if the iterator is still pointing at a pixel</dd>
          </dl>
        </section>
        <section id="related">
          <h2>Related</h2>
          <dl class="m-doc">
                            <dt>
              <div class="m-doc-template">template&lt;typename T&gt;</div>
              using <a href="#dip-ConstImageIterator-T" class="m-doc">dip::<wbr />ConstImageIterator</a> = <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>

            </dt>
            <dd>A const iterator to iterate over all pixels of an image, or all lines of an image. <a href="#dip-ConstImageIterator-T">more...</a></dd>
          </dl>
        </section>
        <section>
          <h2>Alias documentation</h2>
                        <section class="m-doc-details" id="dip-ConstImageIterator-T"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename T&gt;
<br>                template&lt;typename T&gt;
              </div>
              using <a href="#dip-ConstImageIterator-T" class="m-doc-self">dip::<wbr />ConstImageIterator</a> = <a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>

            </h3>
            <p>A const iterator to iterate over all pixels of an image, or all lines of an image.</p>
<p>This iterator is identical to <a href="dip-ImageIterator-T.html"><code>dip::ImageIterator</code></a>, but with a const value type.</p>
<p>Satisfies all the requirements for a non-mutable <a href="http://en.cppreference.com/w/cpp/iterator">ForwardIterator</a>.</p>
          </div></section>
        </section>
        <section>
          <h2>Function documentation</h2>
                        <section class="m-doc-details" id="dip-ImageIterator-T-ImageIterator-Image-CL-UnsignedArray-CL-UnsignedArray--UnsignedArray-CL-dip-uint-"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename T&gt;
              </div>
              <span class="m-doc-wrap-bumper">
                </span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-ImageIterator-Image-CL-UnsignedArray-CL-UnsignedArray--UnsignedArray-CL-dip-uint-" class="m-doc-self">ImageIterator</a>(</span><span class="m-doc-wrap"><a href="dip-Image.html" class="m-doc">dip::Image</a> const&amp; image,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp; origin,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> sizes,
              <a href="supporttypes.html#dip-UnsignedArray" class="m-doc">dip::UnsignedArray</a> const&amp; spacing = {},
              <a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a> procDim = std::numeric_limits<dip::uint>::max())</span></span>
            </h3>
            <p>To construct a useful iterator, provide an image, an ROI, and optionally a processing dimension.</p>
<p><code>spacing</code> can be an empty array or a scalar, but <code>origin</code> and <code>sizes</code> are expected to contain one value
per image dimension. Iterator coordinates are within the ROI.</p>
          </div></section>
                        <section class="m-doc-details" id="dip-ImageIterator-T-IsOnEdge-C"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename T&gt;
              </div>
              <span class="m-doc-wrap-bumper">bool
                </span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-IsOnEdge-C" class="m-doc-self">IsOnEdge</a>(</span><span class="m-doc-wrap">) const</span></span>
            </h3>
            <p>Return true if the iterator points at a pixel on the edge of the image.</p>
<p>If there is a processing dimension, then the iterator always points at an edge pixel; in this case
only returns true if all pixels on the line are edge pixels (i.e. the first and last pixel of the
line are not counted).</p>
          </div></section>
                        <section class="m-doc-details" id="dip-ImageIterator-T-ProcessingDimension-C"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename T&gt;
              </div>
              <span class="m-doc-wrap-bumper"><a href="supporttypes.html#dip-uint" class="m-doc">dip::uint</a>
                </span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-ProcessingDimension-C" class="m-doc-self">ProcessingDimension</a>(</span><span class="m-doc-wrap">) const</span></span>
            </h3>
            <p>Return the processing dimension, the direction of the lines over which the iterator iterates.</p>
<p>If the return value is larger or equal to the dimensionality (i.e. not one of the image dimensions), then
there is no processing dimension.</p>
          </div></section>
                        <section class="m-doc-details" id="dip-ImageIterator-T-Optimize"><div>
            <h3>
              <div class="m-doc-template">
                template&lt;typename T&gt;
              </div>
              <span class="m-doc-wrap-bumper"><a href="dip-ImageIterator-T.html" class="m-doc">dip::ImageIterator</a>&amp;
                </span><span class="m-doc-wrap"><span class="m-doc-wrap-bumper"><a href="#dip-ImageIterator-T-Optimize" class="m-doc-self">Optimize</a>(</span><span class="m-doc-wrap">)</span></span>
            </h3>
            <p>Optimizes the order in which the iterator visits the image pixels.</p>
<p>The iterator internally reorders and flips image dimensions to change the linear index to match
the storage order (see <a href="dip-Image.html#dip-Image-StandardizeStrides"><code>dip::Image::StandardizeStrides</code></a>).
If the image&rsquo;s strides were not normal, this will significantly increase the speed of reading or
writing to the image. Expanded singleton dimensions are eliminated, meaning that each pixel is
always only accessed once. Additionally, singleton dimensions are ignored.</p>
<p>After calling this function, <code>Coordinates</code> and <code>Index</code> no longer match the input image. Do not
use this method if the order of accessing pixels is relevant, or if <code>Coordinates</code> are needed.</p>
<p>Note that the processing dimension stride could change sign. Use <code>ProcessingDimensionStride</code>.
If the processing dimension was a singleton dimension, or singleton-expanded, the iterator will
no longer have a singleton dimension. In this case, <code>HasProcessingDimension</code> will return false.</p>
<p>The iterator is reset to the first pixel.</p>
          </div></section>
        </section>
      </div>
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