Binarization of dQP using separate absolute value and sign (SAVS) in CABAC
Video coding systems or apparatus utilizing context-based adaptive binary arithmetic coding (CABAC) during encoding and/or decoding, are configured according to the invention with an enhanced binarization of non-zero Delta-QP (dQP). During binarization the value of dQP and the sign are separately encoded using unary coding and then combined into a binary string which also contains the dQP non-zero flag. This invention capitalizes on the statistical symmetry of positive and negative values of dQP and results in saving bits and thus a higher coding efficiency.
1 . A video processing apparatus, comprising:
circuitry configured to transfer a bit stream, wherein the bit stream comprises:
an encoded video, wherein
the encoded video is encoded based on Context-Based Adaptive Binary Arithmetic Coding;
an absolute value of a differential quantization parameter, wherein
the differential quantization parameter is a difference between a quantization parameter of a current coding unit and a predicted quantization parameter of the current coding unit; and
a sign value of the differential quantization parameter, wherein
the absolute value and the sign value are separately encoded in an order from the absolute value to the sign value in the bit stream.
2 . A video processing method, comprising:
transferring a bit stream, wherein the bit stream comprises:
an encoded video, wherein
the encoded video is encoded based on Context-Based Adaptive Binary Arithmetic Coding;
an absolute value of a differential quantization parameter, wherein
the differential quantization parameter is a difference between a quantization parameter of a current coding unit and a predicted quantization parameter of the current coding unit; and
a sign value of the differential quantization parameter, wherein
the absolute value and the sign value are separately encoded in an order from the absolute value to the sign value in the bit stream.
3 . A non-transitory computer-readable medium having stored thereon, computer-executable instructions which, when executed by a computer, cause the computer to execute operations, the operations comprising:
transferring a bit stream, wherein the bit stream comprises:
an encoded video, wherein
the encoded video is encoded based on Context-Based Adaptive Binary Arithmetic Coding;
an absolute value of a differential quantization parameter, wherein
the differential quantization parameter is a difference between a quantization parameter of a current coding unit and a predicted quantization parameter of the current coding unit; and
a sign value of the differential quantization parameter, wherein
the absolute value and the sign value are separately encoded in an order from the absolute value to the sign value in the bit stream.