In High Efficiency Video Coding, the Residual Quad-Yree (RQT) coding is used to encode the prediction residual for both intra and inter Coding Units (CU) and provides improved coding gains. However, this results i...In High Efficiency Video Coding, the Residual Quad-Yree (RQT) coding is used to encode the prediction residual for both intra and inter Coding Units (CU) and provides improved coding gains. However, this results in much higher computational complexities. To address this problem, we develop two fast RQT algorithms for intra- and inter-prediction residual coding respectively. For intra coding, the proposed algorithm selects the best prediction mode in the rate distortion mode decision process using a Prediction Unit (PU) size-dependent fast RQT depth decision on a reduced prediction mode candidates set from the rough mode decision process. For inter coding, in addition to CU size-dependent fast RQT depth decisions, we propose a discriminant analy- sis-based fast depth decision algorithm to det- ermine the best transform unit size. Experimental results show that on average, we can real- ise a 21.29% encoding time saving and 0.03% bit-rate reduction for intra coding, while 15% of the encoding time can be saved with a negligible coding performance loss for inter coding.展开更多
In asynchronous Multiple-Input-Multiple-Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM) over the selective Rayleigh fading channel,the performance of the existing linear detection algorithms improves slow...In asynchronous Multiple-Input-Multiple-Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM) over the selective Rayleigh fading channel,the performance of the existing linear detection algorithms improves slowly as the Signal Noise Ratio (SNR) increases.To improve the performance of asynchronous MIMO-OFDM,a low complexity iterative detection algorithm based on linear precoding is proposed in this paper.At the transmitter,the transmitted signals are spread by precoding matrix to achieve the space-frequency diversity gain,and low complexity iterative Interference Cancellation(IC) algorithm is used at the receiver,which relieves the error propagation by the precoding matrix.The performance improvement is verified by simulations.Under the condition of 4 transmitting antennas and 4 receiving antennas at the BER of 10-4,about 6 dB gain is obtained by using our proposed algorithm compared with traditional algorithm.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61272502the National Basic Research Program of China (973 Program) under Grant No.2010CB327900the National Science Fund for Distinguished Young Scholars under Grant No.61125206
文摘In High Efficiency Video Coding, the Residual Quad-Yree (RQT) coding is used to encode the prediction residual for both intra and inter Coding Units (CU) and provides improved coding gains. However, this results in much higher computational complexities. To address this problem, we develop two fast RQT algorithms for intra- and inter-prediction residual coding respectively. For intra coding, the proposed algorithm selects the best prediction mode in the rate distortion mode decision process using a Prediction Unit (PU) size-dependent fast RQT depth decision on a reduced prediction mode candidates set from the rough mode decision process. For inter coding, in addition to CU size-dependent fast RQT depth decisions, we propose a discriminant analy- sis-based fast depth decision algorithm to det- ermine the best transform unit size. Experimental results show that on average, we can real- ise a 21.29% encoding time saving and 0.03% bit-rate reduction for intra coding, while 15% of the encoding time can be saved with a negligible coding performance loss for inter coding.
基金supported by the Hi-Tech Research and Development Program of China under Grant No.2009AA01Z236the National Natural Science Foundation of China under Grants No.60902027,No.60832007 and No.60901018+1 种基金the Funds under Grant No.9140A21030209DZ02the Fundamental Research Funds for the Central Universities under Grants No.ZYGX2009J008,No.ZYGX2009J010
文摘In asynchronous Multiple-Input-Multiple-Output Orthogonal Frequency Division Multiplexing(MIMO-OFDM) over the selective Rayleigh fading channel,the performance of the existing linear detection algorithms improves slowly as the Signal Noise Ratio (SNR) increases.To improve the performance of asynchronous MIMO-OFDM,a low complexity iterative detection algorithm based on linear precoding is proposed in this paper.At the transmitter,the transmitted signals are spread by precoding matrix to achieve the space-frequency diversity gain,and low complexity iterative Interference Cancellation(IC) algorithm is used at the receiver,which relieves the error propagation by the precoding matrix.The performance improvement is verified by simulations.Under the condition of 4 transmitting antennas and 4 receiving antennas at the BER of 10-4,about 6 dB gain is obtained by using our proposed algorithm compared with traditional algorithm.