JCTVC-O0035 RCE1: Summary Report of HEVC Range Extensions Core Experiment 1 on Inter-Component Decorrelation Methods [W.-S. Kim, T. Nguyen]
(Reviewed Thu 24th morning (GJS & JRO).)
HEVC Range Extensions (RExt) Core Experiment 1 (RCE1) was formed to study proposals on inter-component decorrelation methods as described in RCE1 description, JCTVC-N1121, where four Experiments are included to be tested. In this document, the results of four Experiments are summarized and their performance was studied.
For RGB coding, there is reportedly a crossover. YCbCr 4:4:4 coding works better in the low bit rate range, but there is limit in quality. RGB coding usually consumes more bits due to correlation between color components.
Some prior objections to the technique were related to the encoder side. The technique #2 somewhat alleviates that concern. Some prior similar techniques required the decoder to calculate the prediction scale factor, which is not the case in this scheme. The need for cross-component process is, however, undesirable.
The complexity concerns seemed substantially alleviated, compared to some previous proposals.
(overlapping notes below)
Experiment 1/2: Adaptive prediction (coefficient alpha for predicting the chroma component from luma is adapted locally). Adaptation performed per TU. Experiment 2 uses the original luma sample for prediction when determining the alpha value.
JCTVC-O0202 RCE1: Descriptions and Results for Experiments 1, 2, 3, and 4 [W. Pu, W.-S. Kim, J. Chen, J. Sole, M. Karczewicz (Qualcomm)]
5.1.3RCE1 cross checks
JCTVC-O0086 RCE1: Cross-check on Experiment 1 [A. Minezawa, S. Sekiguchi (Mitsubishi)] JCTVC-O0131 RCE1: Cross Check Results for Experiment 3 and 4 [T. Nguyen (Fraunhofer HHI)] JCTVC-O0264 RCE1: cross-check results of test 2 in inter color component residual prediction (JCTVC-O0202) [K. Kawamura, S. Naito (KDDI)]