INTRA-PREDICTION APPARATUS FOR REMOVING A DIRECTIONAL INTRA-PREDICTION MODE FROM A SET OF PREDETERMINED DIRECTIONAL INTRA-PREDICTION MODES

• US 20190313093A1
• Filed: 06/21/2019
• Published: 10/10/2019
• Est. Priority Date: 12/23/2016
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: FILIPPOV, Alexey Konstantinovich, RUFITSKIY, Vasily Alexeevich
• Granted Patent: US 11,025,908 B2
• Time in Patent Office: Days
• CPC Class Codes: H04N 19/105 Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
• CPC Class Codes: H04N 19/11 among a plurality of spatial predictive coding modes
• CPC Class Codes: H04N 19/119 Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/139 Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/593 involving spatial prediction techniques
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards

Abstract

The disclosure relates to an intra-prediction apparatus for removing a directional intra-prediction mode from a set of predetermined directional intra-prediction modes. The intra-prediction apparatus comprises a reference sample determining unit configured to select the directional intra-prediction mode from the set of predetermined directional intra-prediction modes, and to determine a plurality of available reference samples, a directional intra-prediction mode removing unit configured to remove the directional intra-prediction mode from the set of predetermined directional intra-prediction modes if a length (L_RSlonger) associated with the plurality of available reference samples is smaller than a multiple of a length (L_longer) of a first side of the video coding block for obtaining a reduced set, and an intra-prediction unit configured to intra-predict pixel values of pixels of the rectangular video coding block on the basis of the reduced set. The intra-prediction apparatus can further comprise an area determining unit.

Claims

1. An intra-prediction apparatus for removing a directional intra-prediction mode of a rectangular video coding block from a set of predetermined directional intra-prediction modes, each predetermined directional intra-prediction mode of the set of predetermined directional intra-prediction modes being associated with a predetermined direction, the rectangular video coding block having a first side and a second side, a length of the first side being greater than a length of the second side, the intra-prediction apparatus comprising:

a reference sample determining unit configured to select the directional intra-prediction mode from the set of predetermined directional intra-prediction modes, to determine a plurality of available reference samples on the basis of a predetermined direction of the directional intra-prediction mode, the available reference samples extending along the first side of the rectangular video coding block, and to determine a length associated with the plurality of available reference samples;

a directional intra-prediction mode removing unit configured to compare the length of the first side with the length associated with the plurality of available reference samples, and to remove the directional intra-prediction mode from the set of predetermined directional intra-prediction modes if the length associated with the plurality of available reference samples is smaller than a multiple of the length of the first side for obtaining a reduced set of predetermined directional intra-prediction modes; and

an intra-prediction unit configured to intra-predict pixel values of pixels of the rectangular video coding block on the basis of the reduced set of predetermined directional intra-prediction modes.

2. The intra-prediction apparatus of claim 1, wherein the directional intra-prediction mode removing unit is configured to remove the directional intra-prediction mode from the set of predetermined directional intra-prediction modes if the length associated with the plurality of available reference samples is smaller than twice the length of the first side.

3. The intra-prediction apparatus of claim 1, further comprising:

an area determining unit configured to determine a non-prediction area within the rectangular video coding block upon the basis of the length of the second side and the predetermined direction of the directional intra-prediction mode.

4. The intra-prediction apparatus of claim 3, wherein the area determining unit is configured to determine the non-prediction area within the rectangular video coding block upon the basis of the following equation:

5. The intra-prediction apparatus of claim 3, wherein the area determining unit is further configured to determine a fractional non-prediction area within the rectangular video coding block upon the basis of the length of the first side, the length of the second side, and the predetermined direction of the directional intra-prediction mode.

6. The intra-prediction apparatus of claim 5, wherein the area determining unit is configured to determine the fractional non-prediction area within the rectangular video coding block upon the basis of the following equation:

7. The intra-prediction apparatus of claim 1, wherein the rectangular video coding block is a coding unit, a prediction unit, or a transform unit.

8. An encoding apparatus for encoding a rectangular video coding block, the encoding apparatus comprising:

the intra-prediction apparatus of claim 1 for providing a predicted rectangular video coding block; and

an encoding unit configured to encode the rectangular video coding block on the basis of the predicted rectangular video coding block.

9. A decoding apparatus for decoding an encoded rectangular video coding block, the decoding apparatus comprising:

the intra-prediction apparatus of claim 1 for providing a predicted rectangular video coding block; and

a restoration unit configured to restore a rectangular video coding block on the basis of an encoded rectangular video coding block and the predicted rectangular video coding block.

10. An intra-prediction method for removing a directional intra-prediction mode of a rectangular video coding block from a set of predetermined directional intra-prediction modes, each predetermined directional intra-prediction mode of the set of predetermined directional intra-prediction modes being associated with a predetermined direction, the rectangular video coding block having a first side and a second side, a length of the first side being greater than a length of the second side, the intra-prediction method comprising:

selecting the directional intra-prediction mode from the set of predetermined directional intra-prediction modes;

determining a plurality of available reference samples on the basis of a predetermined direction of the directional intra-prediction mode, the available reference samples extending along the first side of the rectangular video coding block;

determining a length associated with the plurality of available reference samples;

comparing the length of the first side with the length associated with the plurality of available reference samples;

removing the directional intra-prediction mode from the set of predetermined directional intra-prediction modes if the length associated with the plurality of available reference samples is smaller than a multiple of the length of the first side for obtaining a reduced set of predetermined directional intra-prediction modes; and

intra-predicting pixel values of pixels of the rectangular video coding block on the basis of the reduced set of predetermined directional intra-prediction modes.

11. A non-transitory computer readable medium comprising program code for performing the method of claim 10 when executed on a computer.