Patent ID: 9596483
Date: 2017-03-14
CPC Classifications: H04N

Claim:
1. A method of coding intra prediction mode of a block, the method comprising: receiving a current intra prediction mode corresponding to a current block; receiving a first neighboring intra prediction mode corresponding to a first neighboring block and a second neighboring intra prediction mode corresponding to a second neighboring block, wherein the first neighboring block and the second neighboring block are coded before the current block; determining a most probable mode (MPM) set by including the first neighboring intra prediction mode as a first most probable mode of said MPM set if the first neighboring intra prediction mode is available and further including the second neighboring intra prediction mode as a second most probable mode of said MPM set if the second neighboring intra prediction mode is available; providing a flag for the current intra prediction mode to indicate whether the current intra prediction mode belongs to said MPM set; if the flag indicates that the current intra prediction mode belongs to said MPM set, seeking a first predictor hit by using a first intra prediction mode candidate, the first intra prediction mode candidate characterized at least in part, by a minimum of the first neighboring intra prediction mode and the second neighboring intra prediction mode; if the first predictor hit is obtained, providing a first code word indicative of the current intra prediction mode being equal to the minimum of the first neighboring intra prediction mode and the second neighboring intra prediction mode; if the first predictor hit is not obtained, seeking a second predictor hit by using a second intra prediction mode candidate, the second intra prediction mode candidate characterized at least in part, by a maximum of the first neighboring intra prediction mode and the second neighboring intra prediction mode; if the second predictor hit is obtained, providing a second code word indicative of the current intra prediction mode being equal to the maximum of the first neighboring intra prediction mode and the second neighboring intra prediction mode; if the second predictor hit is not obtained, decrementing the current intra prediction mode a first time to provide a first decremented current intra prediction mode if the current intra prediction mode exceeds the minimum of the first neighboring intra prediction mode and the second neighboring intra prediction mode; and decrementing the current intra prediction mode a second time to provide a second decremented current intra prediction mode if the first decremented current intra prediction mode exceeds or is equal to the maximum of the first neighboring intra prediction mode and the second neighboring intra prediction mode.