Tham khảo tài liệu 'vision systems - applications part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Optical Correlator based Optical Flow Processor for Real Time Visual Navigation 231 Figure 9. Possible OF processor housing configuration The operation of the presented optoelectronic processor is briefly explained in the following. The lens forms an image of the surrounding environment on the input image sensor. After exposure the image data are recorded in an on-chip memory within the image sensor. The fragments for correlation are cut from two sequential frames according to the preprogrammed pattern - this operation is also performed within the input image sensor. The fragments prepared for correlation are sent to the SLM. Coherent light emitted by a laser diode reflects from the aluminized side of a glass block and illuminates the SLM surface via the embedded lens can be formed as a spherical bulb on the surface of the block . The phase of the wave front reflected from the SLM is modulated by the input image. It is focused by the same lens and forms after intermediate reflection the amplitude image of the Fourier spectrum of the input image on the surface of the Spectrum Correlation Image Sensor SCIS . After a second optical Fourier transform the correlation image is obtained. The optical flow vector equal to the shift between the correlated fragments is calculated from the correlation peaks positions within the correlation image. This operation is performed directly inside the SCIS chip. The coordinates of the OF vectors are sent to the output buffers installed on a small printed board. The expected performances of the OE-OFP Table 1 have been estimated on the base of the conceptual design of the processor and the results of simulation experiments taking into account also the test results of the existing hardware models of the optical correlator developed within previous projects Tchernykh et al. 2004 Janschek et al. 2004a . Input 3D scene Output optical-flow fields Optical-flow resolution max 64x64 4096 vectors field Optical-flow resolution min 8x8 64 vectors
