Rice Parameter Derivation for Parallel CTU Row Video Decoding

The patent segments the video data processing into independent CTU rows, where each row can be processed in parallel. By limiting history counter dependencies to within the same CTU row and initializing history counters for each row, the patent enables parallel processing of multiple rows while maintaining coding efficiency through intra-row history-based Rice parameter derivation.

The patent introduces history counter storage variables as intermediaries to manage the transition of history counter values between parallel CTU row processing. These storage variables act as buffers that allow each parallel thread to access necessary history information without creating conflicts, thereby maintaining coding stability while enabling parallel processing.

The patent applies local quality by maintaining history counter values within each CTU row while allowing parallel processing of different rows. Each row preserves its own history context locally through the history counter storage variables, ensuring that history information is not lost within the parallel processing structure. The initialization only occurs at the start of each row, not within rows, preserving local history quality.