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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ISPRS-Archives</journal-id>
<journal-title-group>
<journal-title>The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences</journal-title>
<abbrev-journal-title abbrev-type="publisher">ISPRS-Archives</abbrev-journal-title>
<abbrev-journal-title abbrev-type="nlm-ta">Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci.</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">2194-9034</issn>
<publisher><publisher-name>Copernicus Publications</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/isprs-archives-XLIX-B2-2026-509-2026</article-id>
<title-group>
<article-title>Affine Invariant OpenCV Descriptors and the Effects on Aerial Photogrammetry</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>O’Keeffe</surname>
<given-names>Evan</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Laefer</surname>
<given-names>Debra F.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Mangina</surname>
<given-names>Eleni</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Center for Urban Science + Progress, Tandon School of Engineering, New York University, 370 Jay Street, 13th Floor, Brooklyn, NY 11201, USA</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Department of Civil, Urban, and Environmental Engineering, Tandon School of Engineering, New York University, Brooklyn, NY, USA</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>School of Computer Science, University College Dublin, Belfield, Dublin, 4, Ireland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>23</day>
<month>07</month>
<year>2026</year>
</pub-date>
<volume>XLIX-B2-2026</volume>
<fpage>509</fpage>
<lpage>516</lpage>
<permissions>
<copyright-statement>Copyright: &#x000a9; 2026 Evan O’Keeffe et al.</copyright-statement>
<copyright-year>2026</copyright-year>
<license license-type="open-access">
<license-p>This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this licence, visit <ext-link ext-link-type="uri"  xlink:href="https://creativecommons.org/licenses/by/4.0/">https://creativecommons.org/licenses/by/4.0/</ext-link></license-p>
</license>
</permissions>
<self-uri xlink:href="https://isprs-archives.copernicus.org/articles/XLIX-B2-2026/509/2026/isprs-archives-XLIX-B2-2026-509-2026.html">This article is available from https://isprs-archives.copernicus.org/articles/XLIX-B2-2026/509/2026/isprs-archives-XLIX-B2-2026-509-2026.html</self-uri>
<self-uri xlink:href="https://isprs-archives.copernicus.org/articles/XLIX-B2-2026/509/2026/isprs-archives-XLIX-B2-2026-509-2026.pdf">The full text article is available as a PDF file from https://isprs-archives.copernicus.org/articles/XLIX-B2-2026/509/2026/isprs-archives-XLIX-B2-2026-509-2026.pdf</self-uri>
<abstract>
<p>Robust feature descriptors are necessary for computer vision applications such as image matching, photogrammetric three-dimensional (3D) reconstructions, and simultaneous localisation and mapping (SLAM). While most state-of-the-art feature descriptors are invariant to image transformations (such as translation, rotation, and scale) the majority lack stability in tracking points over large 3D perspective transformations. One successful method to solving these large perspective changes is by simulating affine tilts on the latitude and longitude axes of an image. These simulated tilts create greater invariance to changes in 3D perspective. To demonstrate the widespread efficacy of this approach, this paper applies affine simulation to seven state-of-the-art descriptors in OpenCV and to two of the enhanced OpenCV descriptors in OpenMVG to 5 datasets that all include large affine conditions. Invariant descriptors were able to achieve up to a three-fold increase in feature tracking.</p>
</abstract>
<counts><page-count count="8"/></counts>
</article-meta>
</front>
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