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A semi-automatic image-based close range 3D modeling pipeline using a multi-camera configuration.

Rau JY, Yeh PC - Sensors (Basel) (2012)

Bottom Line: This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object.The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner.The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333.

View Article: PubMed Central - PubMed

Affiliation: Department of Geomatics, National Cheng-Kung University, No.1, University Road, Tainan 701, Taiwan. jyrau@mail.ncku.edu.tw

ABSTRACT
The generation of photo-realistic 3D models is an important task for digital recording of cultural heritage objects. This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object. Multiple digital single lens reflex (DSLR) cameras are adopted and fixed with invariant relative orientations. Instead of photo-triangulation after image acquisition, calibration is performed to estimate the exterior orientation parameters of the multi-camera configuration which can be processed fully automatically using coded targets. The calibrated orientation parameters of all cameras are applied to images taken using the same camera configuration. This means that when performing multi-image matching for surface point cloud generation, the orientation parameters will remain the same as the calibrated results, even when the target has changed. Base on this invariant character, the whole 3D modeling pipeline can be performed completely automatically, once the whole system has been calibrated and the software was seamlessly integrated. Several experiments were conducted to prove the feasibility of the proposed system. Images observed include that of a human being, eight Buddhist statues, and a stone sculpture. The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner. The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333. It demonstrates the feasibility of the proposed low-cost image-based 3D modeling pipeline and its applicability to a large quantity of antiques stored in a museum.

No MeSH data available.


Datum definition and changing of the inclination angle of the wooden plate for the construction of a convergent imaging geometry.
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f7-sensors-12-11271: Datum definition and changing of the inclination angle of the wooden plate for the construction of a convergent imaging geometry.

Mentions: Figure 7 illustrates how to define the object space coordinates (datum). The X-axis is parallel to the cameras' alignment orientation; the Y-axis falls on the plane of the wooden plate; and the Z-axis points towards the camera. Generally, the X, Y and Z values of the object space should be shifted as being positive and the EOPs close to vertical imaging are utilized in multi-image matching. This is similar to aerial photography for topographic mapping. Figure 8 depicts the bundle adjustment results and the bundles from one target to all cameras. A strong convergent imaging geometry with high redundancy of image measurement is shown that results in high accuracy and reliable EOPs for further surface modeling. As long as the cameras' relative orientation remains the same, we do not have to redo multi-camera calibration even when photographing different objects or during multi-image matching for point cloud generation. The quality assurance can thus be achieved and remains the same for all targets treated.


A semi-automatic image-based close range 3D modeling pipeline using a multi-camera configuration.

Rau JY, Yeh PC - Sensors (Basel) (2012)

Datum definition and changing of the inclination angle of the wooden plate for the construction of a convergent imaging geometry.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472884&req=5

f7-sensors-12-11271: Datum definition and changing of the inclination angle of the wooden plate for the construction of a convergent imaging geometry.
Mentions: Figure 7 illustrates how to define the object space coordinates (datum). The X-axis is parallel to the cameras' alignment orientation; the Y-axis falls on the plane of the wooden plate; and the Z-axis points towards the camera. Generally, the X, Y and Z values of the object space should be shifted as being positive and the EOPs close to vertical imaging are utilized in multi-image matching. This is similar to aerial photography for topographic mapping. Figure 8 depicts the bundle adjustment results and the bundles from one target to all cameras. A strong convergent imaging geometry with high redundancy of image measurement is shown that results in high accuracy and reliable EOPs for further surface modeling. As long as the cameras' relative orientation remains the same, we do not have to redo multi-camera calibration even when photographing different objects or during multi-image matching for point cloud generation. The quality assurance can thus be achieved and remains the same for all targets treated.

Bottom Line: This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object.The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner.The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333.

View Article: PubMed Central - PubMed

Affiliation: Department of Geomatics, National Cheng-Kung University, No.1, University Road, Tainan 701, Taiwan. jyrau@mail.ncku.edu.tw

ABSTRACT
The generation of photo-realistic 3D models is an important task for digital recording of cultural heritage objects. This study proposes an image-based 3D modeling pipeline which takes advantage of a multi-camera configuration and multi-image matching technique that does not require any markers on or around the object. Multiple digital single lens reflex (DSLR) cameras are adopted and fixed with invariant relative orientations. Instead of photo-triangulation after image acquisition, calibration is performed to estimate the exterior orientation parameters of the multi-camera configuration which can be processed fully automatically using coded targets. The calibrated orientation parameters of all cameras are applied to images taken using the same camera configuration. This means that when performing multi-image matching for surface point cloud generation, the orientation parameters will remain the same as the calibrated results, even when the target has changed. Base on this invariant character, the whole 3D modeling pipeline can be performed completely automatically, once the whole system has been calibrated and the software was seamlessly integrated. Several experiments were conducted to prove the feasibility of the proposed system. Images observed include that of a human being, eight Buddhist statues, and a stone sculpture. The results for the stone sculpture, obtained with several multi-camera configurations were compared with a reference model acquired by an ATOS-I 2M active scanner. The best result has an absolute accuracy of 0.26 mm and a relative accuracy of 1:17,333. It demonstrates the feasibility of the proposed low-cost image-based 3D modeling pipeline and its applicability to a large quantity of antiques stored in a museum.

No MeSH data available.