DEM is needed for many branches of earth and environmental sciences such as control of erosion, flood planning, road construction, earth resource's recognition, and soil mapping. There are varieties of resources in generation of DEM, one of them is STEREO satellite IMAGEry. The objective of this research is the study of how to extract DEM from ASTER sensor STEREO IMAGE. ASTER consists of three different subsystems: the Visible and Near-infrared (VNIR) and an additional backward telescope for STEREO, the Shortwave Infrared (SWIR) and the Thermal Infrared (TIR). Each subsystem operates in a different spectral region, with its own telescopes, and is built by a different Japanese company. In addition, one more telescope is used to view backward in the near-infrared spectral band (band 3B) for STEREOscopic capability. IMAGEs of Kashan area, which has been undulating topographic condition, were used. DEM extraction was based on the correlation algorithms between right IMAGE (3N) and left IMAGE (3B).The more correlation these tow IMAGEs, the more precise DEM will be achieved. Finally, by correlation between tow IMAGEs relative elevation attained. The results show that ASTER sensor, using along track imaging will attain the more precise DEM. The result accuracy of these IMAGEs will be less than one pixel. This factor will improve the extraction of another production result by DEM.

IMAGE rectification is an essential part in most multi-view systems. It simplifies the STEREO matching process by limiting the search path to horizontal and parallel lines. The main problem in conventional IMAGE rectification is complexity and mass computation load for calculation of calibration matrix, projection matrix and fundamental matrix. In this paper an efficient and confident method is presented to rectify STEREO IMAGEs based on the correspondence field (CF) that avoids the mentioned matrices. In general this algorithm is able to generate an IMAGE for any new camera position. Especially one can choose the new position in such a way that the virtual camera generates a rectified IMAGE. Both real and simulated STEREO IMAGEs are used to evaluate the proposed algorithm. SIFT algorithm is used to estimate how close is the generated IMAGE to original rectified one. Simulation results show the mean absolute error and standard deviation are about 0.25 and 0.26 pixels respectively and rectified IMAGE is independent of focal ratio.

Security solutions of STEREO IMAGEs are always a major concern during the transmission and communication. In this manuscript, a simple yet efficient framework for encrypting STEREO IMAGEs is formulated using discrete cosine transform (DCT), generalized logistic map, Schur decomposition and magic square method. The framework initiated with the integration of DCT and generalized logistic map to unify both pair of IMAGEs. This unified IMAGE is then encrypted using the Schur decomposition and magic square method. The various experiments and analysis have been done to explore the validity, proficiency and performance of the purport framework.

In this paper, an eye-in-hand STEREO IMAGE-based visual serving controller for industrial 6 degrees of freedom manipulator robots is presented. The visual control algorithms mostly use the relationship between camera speed and changes in IMAGE features, to determine the end-effector movement path. One of the main problems of the classical IBVS method is the inability to estimate the distance of the object related to the camera, which requires peripheral equipment such as a laser rangefinder to estimate the depth. In this study, two cameras were mounted on the end-effector of a 6 DOF manipulator robot. The distance of the object to the camera is estimated by the equations associated with the epipolar plane, and the interaction matrix is updated at any time. For increasing response speed, the IMAGE interaction matrix was divided into two separate parts related to translational and rotational motion, and it was found that only the translational motion part is affected by distance. The control method separates the camera motion into three-stage based on pure rotation, pure translation, and hybrid motion, which has a better time response compared to the classical IBVS control methods. Additionally, a method for position prediction and trajectory estimation of the moving target in order to use in a real-time grasping task is proposed and developed using Recursive Least Square as the trajectory estimators in the IMAGE plane. The simulation results show that the proposed method increases the system response speed and improves the tracking performance.

Three dimensional models generated from cities, due to their wide range of applications, are required by most organizations and institutions. Among numerous 3D reconstruction techniques of urban areas, STEREO-panorama IMAGEs are largely taken into consideration for their full coverage of the environment. In this paper, a new STEREO panorama scanner is presented which utilizes STEREO cameras. The system provides the possibility to extract accurate geometric information for 3D reconstruction of urban areas and STEREO viewing of the surroundings as well. The advantages of such system are: the automation of matching and 3D modelling process, equal resolution over the whole STEREO panorama and the ability to extract precise 3D models in pointcloud format. In this paper, the structure of the system is described, including system implementation, calibration and 3D model generation. Additionally, experimental results of system evaluation are provided. The evaluation results show that the system is enable to generate accurate models for 3D city reconstruction applications. The results demonstrate that once the distance from STEREO scanner to the object is in the range of some 15 meters, consequently the discrepancy of the point distances would be around 57 millimetres.

Purpose: To evaluate the effect of laser in situ keratomileusis (LASIK) on STEREO acuity (SA). Methods: In this prospective study, 200 patients scheduled for LASIK were evaluated for SA preoperatively and one week and one and three months postoperatively by Random Dot test. Patients with preoperative SA worse than 480 sec/arc were excluded.Results: Patients included 138 female (69%) and 62 male (31%) subjects. Spherical equivalent was between -0.5 and -12.0 D. Mean preoperative SA was 124.80±124.64 (range 480-15) sec/arc which deteriorated to 138.30±126.48 sec/arc one week after surgery (P= 0.158) and improved to 111.30±112.15 sec/arc (P=0.002) one month and 103.652±112.20 sec/arc (P=0.001) three months postoperatively. Patients with anisometropia had lower SA. Eventually, SA increased in 5 non-amblyopic anisometropic patients. Overall, STEREO acuity decreased in 9.5%, increased in 32.5% and remained unchanged in 58% of patients (P=0.007).Conclusion: Despite the overall improvement in mean SA after LASIK, a considerable number of patients experienced decreased SA. It seems that anisometropic patients without amblyopia have a higher chance for improvement in SA.

Background: One of the most dramatic sensory ocular anomalies is the low visual acuity of one eye known as amblyopia. The goal of preschool vision screening is to detect children with amblyopia. STEREOpsis is an important indicator of the state of binocularity. Previous studies showed a disagreement on the reliability of STEREO tests as screening tools for amblyopia. This study was performed to compare visual acuity testing with the ability of TNO, Titmus and Randot STEREO tests for detection of amblyopia.Methods: A total of 1000 pupils, aged 6-12 years were examined in a field study in Shiraz. In addition to the 3 STEREO tests of TNO, Titmus and Randot, the examination included visual acuity, cover testing and inspection of red reflex. According to definite fail pass criteria, abnormal cases were referred to pediatric eye clinic for complete eye physical examination. Similar to the first part, in the second part of the study, 100 amblyopic students aged 6-12 years, were referred to pediatric eye clinic for complete physical examination. Sensitivity and specificity of each STEREO test for detection of amblyopia was calculated. Results: In screening situation, the sensitivity of STEREO tests was 55.5% for TNO with a cutoff point of 240", 48.8% for Titmus with a cutoff point of 70" and 44.4% for Randot STEREO test with cutoff point of 100". Specificity of these tests in screening situation was 86.9%, 94.4%, and 98.4% respectively. The respective sensitivity of these STEREO tests in clinical situation was 74%, 68%, and 62%. Conclusion: Considering these fail-pass criteria, none of the TNO, Titmus, and Randot STEREO tests can be recommended as a screening method for detection of amblyopia in children.

Background: Many studies have been performed on validity of different methods for Amblyopia screening and this one was designed to assess the reliability of the TNO test for that purpose.Materials and Methods: This is a diagnostic value study. Visual acuity and STEREO acuity of 100 patients with Amblyopia caused by refractive errors, strabismus with wide angle, or micro strabismus were measured and compared with the STEREO acuity of 300 normal students using TNO test. Statistical analysis carried out to determine sensitivity, specificity, and diagnostic value. Then, positive and negative predictive values were calculated by considering 120 seconds of arc STEREOpsis as the cut off point.Results: Ninety five percent of students had good STEREOpsis (120 second of arc or better). Patients group showed limited STEREOpsis. The most common cause of amblyopia in patients group was refractive errors (62%). The most defective STEREOpsis was clearly associated with wide angle strabismus. In this study TNO test had missed (underestimated) 8% of cases with Amblyopia and had 5% over referral rate but had sufficient power to detect patients with moderate to severe Amblyopia. Its sensitivity and specificity were 85.9% and 97.2% respectively.Conclusion: TNO test seems to be useful for screening purposes of Amblyopia. It is reliable and can be performed without having special skills. Lack of monocular clues, also, increases its value.