Methods and systems for entropy coder initialization

1. A method for decoding a video frame in a video sequence, the method comprising:

receiving a slice header and information including: (i) first information indicating a number of second regions in a first region, and (ii) second information indicating an offset of an i-th second region from an (i−1)th second region in a bitstream, wherein the video frame includes one or more of the first regions and one or more the second regions;

identifying a slice type of a slice;

receiving a flag with only one of: (i) a first value indicating first initialization information and (ii) a second value indicating second initialization information;

initializing a Context-Adaptive Binary Arithmetic Coding (CABAC) context associated with the slice type using the initialization method which is selected using the identified slice type and the received flag; and

decoding the video frame using the identified slice type and the received flag; wherein

in a case that the identified slice type indicates a B-slice type and the value of the flag is equal to the first value, the step of initializing the CABAC context associated with the slice type uses a first initialization method; and

in a case that the identified slice type indicates the B-slice type and the value of the flag is equal to the second value, the step of initializing the CABAC context associated with the slice type uses a second initialization method.

2. The method of claim 1 , wherein the flag is provided in the slice header.