In all video coding standards, the temporal redundancy is reduced by the use of predictive coding. In order to predict the current image signal, a prediction image signal is obtaines from already reconstructed images by using block based motion compensated prediction. A displacement vector is assigned to each block referring to the position of the block in an already reconstructed image. The prediction error signal and the displacement vector are encoded an transmitted. In order to reduce the spatial redundancy of the prediction error signal, transform coding is applied blockwise. The coefficients are quantized and coded by an arithmetic coding.
The goal is the improvement of the prediction error coding
The transform is only efficient if the prediction error samples are correlated. For marginally correlated samples the transform is inefficient. To approach the goal, adaptive prediction error coding in the frequancy and in the spatial domain is applied. For each block of the prediction error signal, either standardized transform coding or spatial domain coding is used. The algorithm with lower costs is chosen. For QCIF, CIF, and SDTV the bit rate is reduced by up to 8% and for HDTV by up to 3% compared to the latest video coding standard H.264/AVC.
[1] M. Narroschke, " Extending H.264/AVC by an adaptive coding of the prediction error",
Proc. of Picture Coding Symposium 2006 , Beijing, China, April 2006
[2] M. Narroschke, H.G. Musmann, "
Adaptive prediction error coding in spatial and frequency domain with a fixed scan in the spatial domain", ITU-T Q.6/SG16, doc. VCEG-AD07, Hangzhou, China, 2006
[3] M. Narroschke, H.G. Musmann, "
Adaptive prediction error coding in spatial and frequency domain for H.264/AVC", ITU-T Q.6/SG16, doc. VCEG-AB06, Bangkok, Thailand, 2006
