Calibration of Low Cost Digital Cameras
Recent developments of digital cameras include smaller Charged Coupled Device (CCD) arrays and reduced costs, which are leading to their utilization in traditional as well as new photogrammetric surveying and mapping applications. Such cameras require careful assessment to determine their metric characteristics, which are essential to carry out photogrammetric activities.
Stability Analysis of Low Cost Digital Cameras
Increasing resolution and reducing costs of off-the-shelf digital cameras are giving rise to their utilization in traditional and new photogrammetric applications, and allowing amateur users to generate high-quality photogrammetric products. For most, if not all photogrammetric applications, the internal metric characteristics of such cameras need to be determined and analyzed. This is achieved by going through a camera calibration and stability analysis process using a specific test field configuration. In a traditional test field, precisely surveyed ground control points (GCPs) are used as control information. The proposed test field in current research involves the utilization of linear features.
Image registration concerns the problem of how to combine data and information from multiple sensors in order to achieve improved accuracy and better inferences about the environment than could be attained through the use of a single sensor.
Change detection is the process of identifying differences in land cover over time. As human and natural forces continue to alter the landscape, it is important to develop monitoring methods to assess and quantify these changes. Recent advances in satellite imagery, in terms of improved spatial and temporal resolutions, are allowing for efficient identification of change patterns and prediction of areas of growth.
Optical & Ranging Sensor Integration
A variety of applications in today's society demand the fast and reliable collection of data about physical objects. Such applications require the availability of information pertaining to the geometric and semantic characteristics of those objects in which surfaces play an important role.
DEM Generation from High Resolution Satellite Imagery
Digital Elevation Model (DEM) generation from remotely sensed imagery is crucial for a variety of mapping applications such as ortho-photo generation, city modeling, object recognition, and creation of perspective views. Recently launched high-resolution imaging satellites (e.g., SPOT-5, IKONOS, QUICKBIRD, ORBVIEW, and EOS-1) constitute an excellent source for efficient, economic, and accurate generation of DEM data for extended areas of the Earth’s surface.
Epipolar Geometry of Linear Array Scanner Scenes
Image resampling according to epipolar geometry is a prerequisite for a variety of photogrammetric tasks such as image matching, DEM generation, ortho-photo generation, aerial triangulation, map compilation, and stereoscopic viewing. The resampling process of imagery captured by frame cameras has been established and implemented in current Digital Photogrammetric Workstations (DPW).
Rigorous versus Approximate Modeling of Linear Array Scanners
Digital frame cameras with resolution and ground coverage comparable to those cameras associated with analogue aerial cameras are not yet available. Therefore, linear array scanners have been introduced on aerial and space borne platforms to overcome this drawback.
Linear Features in Photogrammetry
Photogrammetric manipulation of imagery has been, for the major part, a point-based operation. The utilization of points is still convenient because a few manually digitized points can be accurately obtained to carry out various photogrammetric orientation procedures (e.g., relative and absolute orientation as well as photogrammetric triangulation).
Feature Extraction and Object Recognition
Feature extraction and object recognition has been one of the key research issues addressed by researchers and scientists in the fields of computer vision and digital photogrammetry. The creation of automatic map-making machines is the ultimate objective of digital photogrammetry.