VERIFICATION AND IMPROVING PLANIMETRIC ACCURACY OF AIRBORNE LASER SCANNING DATA WITH USING PHOTOGRAMMETRIC DATA (original) (raw)
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On présente dans cet article une méthode pour géolocaliser les images photogrammétriques à partir de données lidar. Dans cette méthode on utilise les centroïdes des toits de bâtiments rectangulaires comme points d’appui photogrammétriques. Chaque centroïde issu des données lidar constitue l’un des points d’appui de ce canevas, déterminé par ses trois coordonnées et conséquent utilisable comme tel dans les systèmes photogrammétriques classiques. On a réalisé deux essais photogrammétriques pour s’assurer de la faisabilité de cette méthode. Les résultats obtenus ont confirmé qu’il était possible d’utiliser cette méthode pour géolocaliser les images photogrammétriques avec des données lidar.Die Integration photogrammetrischer Bilddaten und Laserscandaten, zweier komplementärer Datenquellen, bietet die Möglichkeit zur Optimierung der photogrammetrischen Erfassung räumlicher Information hinsichtlich Genauigkeit und Zuverlässigkeit. 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Die Methode stützt sich auf die Schwerpunkte rechteckiger Dachflächen von Gebäuden als Passpunkte in der photogrammetrischen Orientierung. An Hand von zwei photogrammetrischen Beispielen wird die Anwendbarkeit der Methode nachgewiesen.La integración de imágenes fotogramétricas y datos lidar se está convirtiendo en un procedimiento muy eficaz en la optimización de las técnicas de restitución fotogramétrica. El carácter complementario de los datos lidar y fotogramétricos permite optimizar muchos procedimientos de extracción de información espacial tridimensional de los datos. Por ejemplo, las imágenes fotogramétricas permiten la extracción exacta de contornos de edificios al tiempo que el lidar aporta datos tridimensionales exactos de las superficies físicas de los edificios. Estas propiedades ofrecen la ventaja de combinar los dos tipos de datos para conseguir una reconstrucción más robusta y completa de los objetos tridimensionales. Los procedimientos fotogramétricos requieren de parámetros de orientación externa de las imágenes para la restitución. Pese a la disponibilidad de sistemas integrados de navegación inercial y GPS para la georreferenciación directa de las imágenes, la mayoría de los sistemas fotogramétricos disponibles requieren de información de control para la restitución fotogramétrica. Con la mejora de la exactitud que los sistemas lidar han experimentada en los últimos años, sus datos se han convertido en una fuente asequible de control fotogramétrico. Los objetos puntuales son el principal tipo de información de control para la triangulación fotogramétrica, aunque también se han utilizado objetos lineales y teselas planas. Este artículo presenta un método de georreferenciación de imágenes fotogramétricas a partir de datos lidar utilizando los centroides de los tejados de edificios rectangulares como puntos de apoyo en el proceso fotogramétrico. El centroide de un tejado rectangular obtenido de los datos lidar es equivalente a un punto de apoyo con coordenadas tridimensionales y, por lo tanto, puede utilizarse en los sistemas fotogramétricos tradicionales. Se llevaron a cabo dos experimentos fotogramétricos para verificar la viabilidad de la metodología y los resultados confirman la aplicabilidad de esta metodología propuesta de georreferenciación de imágenes fotogramétricas mediante datos lidar.
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ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2012
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