SAO Signaling Decoupling for HEVC CABAC Throughput

The patent segments the SAO signaling process into distinct phases: first all context-coded bins are transmitted, then all bypass-coded bins are transmitted. This segmentation separates the two coding methods that were previously interleaved, allowing the CABAC engine to process context-coded bins continuously without interruption from bypass-coded bins, thereby improving throughput while maintaining coding flexibility through the preserved choice of coding methods.

The patent extracts the bypass-coded bins from the interleaved structure and separates them into a distinct transmission phase. By taking out the bypass-coded bins and transmitting them after all context-coded bins, the patent reduces the overhead and complexity of the signaling structure while preserving the precision benefits of both coding methods. This extraction eliminates the inefficiencies of interleaving while maintaining the high precision required for accurate SAO parameter signaling.

The patent applies preliminary action by transmitting all context-coded bins first, establishing the SAO type and parameters before transmitting the bypass-coded bins. This preliminary transmission of the more complex context-coded information allows the decoder to prepare appropriate processing structures in advance, simplifying the overall bitstream structure while maintaining the ability to signal multiple SAO types and offset values for high reconstruction accuracy.