It is shown that the polynomials based image registration, which is widely used in remote sensing field, does not have a sound mathematical basis. In fact, there seems no theoretical basis for the polynomials based tr...It is shown that the polynomials based image registration, which is widely used in remote sensing field, does not have a sound mathematical basis. In fact, there seems no theoretical basis for the polynomials based transform to outperform the affine transformation, a much simpler one,in image registration. If the transformation functions are polynomials of order n, the corresponding scene is shown to be in general the intersection of two curved surfaces of order n + 1, in other words,a space curve. In some special cases, the scene is approaching to a plane. To our knowledge, such results did not appear in the literature previously.展开更多
A semantic unit based event detection scheme in soccer videos is proposed in this paper.The scheme can be characterized as a three-layer framework. At the lowest layer, low-level featuresincluding color, texture, edge...A semantic unit based event detection scheme in soccer videos is proposed in this paper.The scheme can be characterized as a three-layer framework. At the lowest layer, low-level featuresincluding color, texture, edge, shape, and motion are extracted. High-level semantic events aredefined at the highest layer. In order to connect low-level features and high-level semantics, wedesign and define some semantic units at the intermediate layer. A semantic unit is composed of asequence of consecutives frames with the same cue that is deduced from low-level features. Based onsemantic units, a Bayesian network is used to reason the probabilities of events. The experiments forshoot and card event detection in soccer videos show that the proposed method has an encouragingperformance.展开更多
A Vector piecewise polynomial (VPP) approximation algorithm is proposed for environ-ment compensation of speech signals degraded by both additive and convolutive noises. By investi-gating the model of the telephone en...A Vector piecewise polynomial (VPP) approximation algorithm is proposed for environ-ment compensation of speech signals degraded by both additive and convolutive noises. By investi-gating the model of the telephone environment, we propose a piecewise polynomial, namely twolinear polynomials and a quadratic polynomial, to approximate the environment function precisely.The VPP is applied either to the stationary noise, or to the non stationary noise. In the first case,the batch EM is used in log-spectral domain; in the second case the recursive EM with iterativestochastic approximation is developed in cepstral domain. Both approaches are based on the mini-mum mean squared error (MMSE) sense. Experimental results are presented on the application ofthis approach in improving the performance of Mandarin large vocabulary continuous speech recog-nition (LVCSR) due to the background noises and different transmission channels (such as fixedtelephone line and GSM). The method can reduce the average character error rate (CER) by a-bout 18%.展开更多
基金Supported by National Natural Science Foundation of P. R. China (60175009, 60121302) Corresponding author:Hu Zhan-Yi
文摘It is shown that the polynomials based image registration, which is widely used in remote sensing field, does not have a sound mathematical basis. In fact, there seems no theoretical basis for the polynomials based transform to outperform the affine transformation, a much simpler one,in image registration. If the transformation functions are polynomials of order n, the corresponding scene is shown to be in general the intersection of two curved surfaces of order n + 1, in other words,a space curve. In some special cases, the scene is approaching to a plane. To our knowledge, such results did not appear in the literature previously.
文摘A semantic unit based event detection scheme in soccer videos is proposed in this paper.The scheme can be characterized as a three-layer framework. At the lowest layer, low-level featuresincluding color, texture, edge, shape, and motion are extracted. High-level semantic events aredefined at the highest layer. In order to connect low-level features and high-level semantics, wedesign and define some semantic units at the intermediate layer. A semantic unit is composed of asequence of consecutives frames with the same cue that is deduced from low-level features. Based onsemantic units, a Bayesian network is used to reason the probabilities of events. The experiments forshoot and card event detection in soccer videos show that the proposed method has an encouragingperformance.
文摘A Vector piecewise polynomial (VPP) approximation algorithm is proposed for environ-ment compensation of speech signals degraded by both additive and convolutive noises. By investi-gating the model of the telephone environment, we propose a piecewise polynomial, namely twolinear polynomials and a quadratic polynomial, to approximate the environment function precisely.The VPP is applied either to the stationary noise, or to the non stationary noise. In the first case,the batch EM is used in log-spectral domain; in the second case the recursive EM with iterativestochastic approximation is developed in cepstral domain. Both approaches are based on the mini-mum mean squared error (MMSE) sense. Experimental results are presented on the application ofthis approach in improving the performance of Mandarin large vocabulary continuous speech recog-nition (LVCSR) due to the background noises and different transmission channels (such as fixedtelephone line and GSM). The method can reduce the average character error rate (CER) by a-bout 18%.
