In this work, a texture mapping scheme with massive data is proposed based on quadtree for multi-level scene modeling. A simplified LOD model is established for the multi-resolution texture data which enhance the fidelity of multilevel target simulation in scene. By predictable appreciation according to viewpoint displacement in real-time simulation, the correspongding nodes and level details of quadtree are confirmed when the dynamical scene is loading. This mean effectively decreases the schedule data in real-time simulation. A validation experiment has been performed to certificate the availabitity and improvement.
The photoelectric theodolite is an important scheme to realize the tracking, detection, quantitative measurement and performance evaluation of weapon systems in ordnance test range. With the improvement of stability requirements for target tracking in complex environment, infrared scene simulation with high sense of reality and complex interference has become an indispensable technical way to evaluate the track performance of photoelectric theodolite. And the tail flame is the most important infrared radiation source of the weapon system. The dynamic tail flame with high reality is a key element for the photoelectric theodolite infrared scene simulation and imaging tracking test. In this paper, an infrared simulation method for the full-path tracking of tail flame by photoelectric theodolite is proposed aiming at the faint boundary, irregular, multi-regulated points. In this work, real tail images are employed. Simultaneously, infrared texture conversion technology is used to generate DDS texture for a particle system map. Thus, dynamic real-time tail flame simulation results with high fidelity from the theodolite perspective can be gained in the tracking process.
Image quality is an important factor that influences the dynamic target information perception; it is the key factor of real-time target state analysis and judgment. In order to solve the multi-observation station comparison and video optimum seeking problem in the process of target information perception and recognition, an image quality assessment method based on visual characteristics is proposed for infrared target tracking. First, it analyses the basic infrared target image characteristics and application requirements, analyses the status and problems of the multi station optimum seeking technology. According to the expected research results, the processing flow of image processing is established. Then, the image quality objective assessment index is established, which reflects the basic characteristics of the target image, and the assessment index is integrated into the normalized assessment function. According to the quality assessment function, the infrared image quality assessment based on infrared target recognition and image analysis processing is realized, which is mainly characterized by the region of interest and dynamic visual characteristics. And on the basis of this technology, the real-time optimum seeking of multi station infrared target tracking image is completed. In order to verify the effectiveness of the method and the practical application effect, it designs the quality assessment and comparison of different station infrared images. Example shows that the method proposed in this paper can realize multi-observation station infrared image assessment comparison, image quality sorting, the optimum seeking of the infrared image based on the quality assessment. The results accord with the characteristics of infrared target image and dynamic visual characteristics.
Haze, fog, and smoke are turbid medium in the atmosphere which usually degrade viewing condition of outdoor scenes. The resulted images lose contrast and color fidelity with serious degradation. Due to loss of large detailed information of measured scene, it will usually lead to invalid detection and measurement. The suspended particles in the atmosphere and the scene being measured give rise to polarization changes by their reflection. In the process of reflection, absorption and scattering, the object itself can be determined by its own polarization characteristics. Based on this point, we proposed an approach for target vision through haze. This approach is based on the polarization differences between the scene being measured and the scattering background to move the haze effects. It can realize a great visibility enhancement and enable the scene rendering even if imaged under restricted viewing conditions with low polarization. In this work, the detailed theoretical operation principle is presented. A validating imaging system is established and the corresponding experiment is carried out. We present the experimental results of haze-free image of scene with recovered high contrast. This method also can be used to effectively enhance the imaging performance of any other optical system.
Proc. SPIE. 9142, Selected Papers from Conferences of the Photoelectronic Technology Committee of the Chinese Society of Astronautics: Optical Imaging, Remote Sensing, and Laser-Matter Interaction 2013
KEYWORDS: Reflectors, Mirrors, Real time imaging, Imaging systems, Cameras, Sensors, Temporal resolution, High speed cameras, Servomechanisms, High speed photography
The high speed tracing imaging technique based on a scanning reflector, can realize a real-time tracking imaging measurement of the live scene. It can compensate field of view of the fixed high speed camera and scanning velocity of photoelectric theodolites. In this work, a synchronous tracking system realized by a rotating mirror is introduced. The imaging performance is analyzed in detail. The scheme to gain flight characteristics of targets is presented. A certificated test is performed and its results confirmed the feasibility of this system.
The static wind imaging interferometer, based on a four-phase-divided mirror, is an attractive approach to acquiring the wind velocity and temperature of the upper atmosphere. Herein the operational principle of the interferometer is presented in detail. The throughput is theoretically analyzed with consideration of the reflections and transmittances of each systemic component. The throughput expression is derived by employing the Fresnel theorem. We conducted simulations, and the results show that the energy transmittance reaches 20% on the surface with high reflectivity-coating film when the inclination angle of the input light is limited to the range of −5 to +5 deg. The results presented herein provide a theoretical basis for the static design configuration and coating for the upper atmosphere wind imaging interferometer.
Theory and simulations of a novel hyperspectral imaging polarimeter for remote sensing are presented. The spectropolarimeter is formed by cascading two laser servocontrol modified wave plates (MWP) and a polarization interference imaging spectrometer (PIIS). Using the phase modulation of the MWPs, this setup enables PIIS, originally developed by C. Zhang, to be extended for full polarization detection without dividing the interference fringes into channels as that in Oka's original channeled polarimeter. In this way, we can get the polarization information with higher spectral resolution. Besides, the data can be acquired with simpler operation. Aside from this feature, the configuration retains the advantages of both elements: the high precision phase modulation of the MWPs and the high spectral, spatial resolution, and higher throughput of the PIIS. A design example with spectral resolution 100 cm−1 and range 0.4-1.0 μm is given.