A method of encoding video using a video encoder, wherein the video encoder is configured to employ context-adaptive entropy encoding using a context model, the context model having a context model state defining the probability associated with each context defined in the context model, wherein the video encoder includes a memory, the memory having stored therein a pre-defined context model state for initialization of the context model, and wherein the video encoder includes a buffer, the buffer having stored therein a predetermined number of at least two context model states, each of the predetermined number of stored context model states being the context model state after context-adaptive encoding of a respective previously-encoded picture of the video that has been encoded in the video encoder previous to a current picture of the video, the context model states stored in the buffer respectively resulting from context-adaptive encoding of the predetermined number of most recent pictures of the video previous to the current picture, the method comprising, for encoding the current picture of the video: selecting one of the predetermined number of stored context model states from the buffer based on one or more criteria relative to the current picture, wherein said selecting is based on the previously-encoded picture being a reference picture for a prediction of the current picture; initializing the context model for context-adaptively encoding the current picture using the selected one of the predetermined number of stored context model states; context-adaptively entropy encoding the current picture to produce a bitstream of encoded data, wherein the context-adaptive entropy encoding includes progressively updating the selected one of the predetermined number of stored context model states as bins are encoded, thereby yielding an updated context model state associated with the current picture after the context-adaptively entropy encoding; storing, in the buffer, the updated context model state associated with the current picture after the context-adaptively entropy encoding, in place of the oldest context model state among the predetermined number of context model states stored in the buffer; and prior to selecting, determining that the context model is not to be initialized using the pre-defined context model state for the current picture. selecting one of the predetermined number of stored context model states from the buffer based on one or more criteria relative to the current picture, wherein said selecting is based on the previously-encoded picture being a reference picture for a prediction of the current picture; initializing the context model for context-adaptively encoding the current picture using the selected one of the predetermined number of stored context model states; context-adaptively entropy encoding the current picture to produce a bitstream of encoded data, wherein the context-adaptive entropy encoding includes progressively updating the selected one of the predetermined number of stored context model states as bins are encoded, thereby yielding an updated context model state associated with the current picture after the context-adaptively entropy encoding; storing, in the buffer, the updated context model state associated with the current picture after the context-adaptively entropy encoding, in place of the oldest context model state among the predetermined number of context model states stored in the buffer; and prior to selecting, determining that the context model is not to be initialized using the pre-defined context model state for the current picture.