Distributed video coding (DVC) is a new video coding approach based on Wyner-Ziv theorem. The novel uplink-friendly DVC, which offers low-complexity, low-power consuming, and low-cost video encoding, has aroused mor...Distributed video coding (DVC) is a new video coding approach based on Wyner-Ziv theorem. The novel uplink-friendly DVC, which offers low-complexity, low-power consuming, and low-cost video encoding, has aroused more and more research interests. In this paper a new method based on multiple view geometry is presented for spatial side information generation of uncalibrated video sensor network. Trifocal tensor encapsulates all the geometric relations among three views that are independent of scene structure; it can be computed from image correspondences alone without requiring knowledge of the motion or calibration. Simulation results show that trifocal tensor-based spatial side information improves the rate-distortion performance over motion compensation based interpolation side information by a maximum gap of around 2dB. Then fusion merges the different side information (temporal and spatial) in order to improve the quality of the final one. Simulation results show that the rate-distortion gains about 0.4 dB.展开更多
Objective To observe the changes on multifocal electroretinography (MfERG) in the fellow eyes of patients with high myopia without fundus lesions and rhegmatogenous retinal detachment (RRD). Methods MfERG was perf...Objective To observe the changes on multifocal electroretinography (MfERG) in the fellow eyes of patients with high myopia without fundus lesions and rhegmatogenous retinal detachment (RRD). Methods MfERG was performed in 66 patients ( 66 eyes) which were grouped into : emmetropes ( n = 22 ) as the control eye ; high myopes without fundus lesions ( corrected visual acuity ≥ 1. 0, n = 15 ) ; and fellow eyes of high myopics with RRD (n = 29 ). The first-order kernels N1, P1, N2 response density and latency were analyzed. Results When compared with the emmetropes group, the high myopes group had significantly reduced N1 , PI , and N2 wave response densities in rings 1 to 6 ( P 〈 0. 05 ), delayed N1 wave latency in rings 3 to 6, and P1 wave latency in rings 3 to 5 ( P 〈 0. 05 ). The fellow eyes group had significantly reduced N1, P1, and N2 wave response densities in rings 1 to 6 and significantly delayed N1 and P1 wave latencies in rings 3 to 6 ( P 〈0. 05) compared with the emmetropes group. Compared with the high myopes group, P1 wave response densities in rings 1 to 6, N1 wave response densities in rings 1,3, 4, and 6, and N2 wave response density in ring 1 were significantly decreased in the fellow eyes group ( P 〈 0. 05 ) ; whereas there were no significant differences in latencies between the two groups (P 〉0.05). Conclusion MfERG can sensitively assess the early changes in visual function in fellow eyes in patients with RRD.展开更多
文摘Distributed video coding (DVC) is a new video coding approach based on Wyner-Ziv theorem. The novel uplink-friendly DVC, which offers low-complexity, low-power consuming, and low-cost video encoding, has aroused more and more research interests. In this paper a new method based on multiple view geometry is presented for spatial side information generation of uncalibrated video sensor network. Trifocal tensor encapsulates all the geometric relations among three views that are independent of scene structure; it can be computed from image correspondences alone without requiring knowledge of the motion or calibration. Simulation results show that trifocal tensor-based spatial side information improves the rate-distortion performance over motion compensation based interpolation side information by a maximum gap of around 2dB. Then fusion merges the different side information (temporal and spatial) in order to improve the quality of the final one. Simulation results show that the rate-distortion gains about 0.4 dB.
文摘Objective To observe the changes on multifocal electroretinography (MfERG) in the fellow eyes of patients with high myopia without fundus lesions and rhegmatogenous retinal detachment (RRD). Methods MfERG was performed in 66 patients ( 66 eyes) which were grouped into : emmetropes ( n = 22 ) as the control eye ; high myopes without fundus lesions ( corrected visual acuity ≥ 1. 0, n = 15 ) ; and fellow eyes of high myopics with RRD (n = 29 ). The first-order kernels N1, P1, N2 response density and latency were analyzed. Results When compared with the emmetropes group, the high myopes group had significantly reduced N1 , PI , and N2 wave response densities in rings 1 to 6 ( P 〈 0. 05 ), delayed N1 wave latency in rings 3 to 6, and P1 wave latency in rings 3 to 5 ( P 〈 0. 05 ). The fellow eyes group had significantly reduced N1, P1, and N2 wave response densities in rings 1 to 6 and significantly delayed N1 and P1 wave latencies in rings 3 to 6 ( P 〈0. 05) compared with the emmetropes group. Compared with the high myopes group, P1 wave response densities in rings 1 to 6, N1 wave response densities in rings 1,3, 4, and 6, and N2 wave response density in ring 1 were significantly decreased in the fellow eyes group ( P 〈 0. 05 ) ; whereas there were no significant differences in latencies between the two groups (P 〉0.05). Conclusion MfERG can sensitively assess the early changes in visual function in fellow eyes in patients with RRD.