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Register a new userEvaluation of the effect of images' geometric resolution on the 3D model quality in automated close-range photogrammetry
تقييم تأثير دقة التمييز الهندسية للصور على نوعية النموذج ثلاثي الأبعاد في المساحة التصويرية القريبة المؤتمتة
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Tishreen University ورقة بحثية
Publication date
2018
fields
topography
and research's language is
العربية
Created by
Shamra Editor
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إن الهدف الرئيسي لهذا البحث هو دراسة تأثير دقة التمييز الهندسية للصور فقط على النوعية الهندسية للنموذج ثلاثي الأبعاد المحسوب منها. تم في هذا البحث تثبيت كل العناصر التي تؤثر على نوعية النموذج و تغيير دقة التمييز فقط للصور المستخدمة. يعتبر عدد الصور الملتقطة للعنصر، عدد نقاط الضبط و توزعها و دقتها، آلة التصوير المستخدمة و كونها معايرة أم لا، من أهم العوامل المؤثرة على عملية النمذجة. لتحييد تأثير العوامل الداخلية لآلة التصوير المستخدمة في التقاط الصور، قمنا بعملية معايرة لهذه الآلة، كما حرصنا على التخطيط المسبق لعملية التصوير و ذلك لتفادي المشاكل الناتجة عن نقص أو زيادة عدد الصور و التي تؤثر بشكل مباشر على نوعية النموذج و كماليته. و من ناحية أخرى، تم استخدام معطيات ضبط دقيقة تم الحصول عليها من أعمال مساحية دقيقة (شبكة جيوديزية أفقية و شبكة تسوية). في هذه الدراسة سنختبر تأثير دقة تمييز الصور فقط على توليد غمامة كثيفة من النقاط بتطبيق طريقة البنية انطلاقاً من الحركة Structure from Motion (SfM) و استنتاج النموذج السطوحي منها و الصورة المصححة عامودياً لواجهة من واجهات منشأ في جامعة تشرين.
The main objective of this research is to study the effect of the accuracy of images' geometric resolution only on the geometric quality of the resulted three-dimensional model. In this research, all factors that affect the quality of the model are fixed and the geometric resolution is changed only for the used images. The number of captured images, the number and the distribution and the accuracy of control points, the camera being used and whether or not it is calibrated, are among the most important factors influencing the modeling process. In order to neutralize the effect of the inner parameters of the used camera, a process of calibration was achieved. On the other hand, we have pre-planned the process of photography to avoid problems resulting from the lack or increase the number of images, that directly affect the quality and completeness of the model. In addition, accurate control data obtained from precise survey work (horizontal geodetic network and leveling network) was applied. In this study, we examined the effect of image resolution on the generation of a dense cloud of points by applying the Structure from Motion (SfM) and deducing the surface model and the orthophoto of a facade of a building at Tishreen University.
References used
Remondino، F.، Spera، M.G.، Nocerino، E.، Menna، F.، Nex، F.، 2014. State of the art in high density image matching. In: The Photogrammetric Record 29، pp. 144–166. doi:10.1111/phor.12063
Förstner, W., 1986. A feature-based correspondence algorithm for image matching. International Archives of Photogrammetry and Remote Sensing 26, 150–166
Nocerino, E., Menna, F., Remondino F., 2014. Accuracy of typical photogrammetric networks in cultural heritage 3D modelling projects. The Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci., Volume XL-5, 465-472
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