Intra-prediction apparatus for removing a directional intra-prediction mode from a set of predetermined directional intra-prediction modes
An intra-prediction method includes: determining, by an intra-prediction apparatus, a directional intra-prediction mode for a rectangular video coding block from an extended set of directional intra-prediction modes, wherein the extended set of directional intra-prediction modes includes extended directional intra-prediction modes and conventional directional intra-prediction modes and determining, by the intra-prediction apparatus, a plurality of available reference samples based on a direction of the directional intra-prediction mode. The method further includes: intra-predicting, by the intra-prediction apparatus, pixel values of pixels of the rectangular video coding block based on the plurality of available reference samples.
1. An intra-prediction method, comprising:
obtaining, by an intra-prediction apparatus, a conventional directional intra-prediction mode based on signaled information;
determining, by the intra-prediction apparatus, an extended directional intra-prediction mode based on the conventional directional intra-prediction mode for a rectangular video coding block, wherein the rectangular video coding block has a first side and a second side, and wherein a length of the first side is greater than a length of the second side;
determining, by the intra-prediction apparatus, a plurality of available reference samples based on a direction of the extended directional intra-prediction mode; and
intra-predicting, by the intra-prediction apparatus, pixel values of pixels of the rectangular video coding block based on the plurality of available reference samples;
wherein the extended directional intra-prediction mode for the rectangular video coding block is determined further based on an aspect ratio of the rectangular video coding block.
2. The intra-prediction method of claim 1 , wherein the extended directional intra-prediction mode for the rectangular video coding block is determined based on a mapping between the extended directional intra-prediction mode and the conventional directional intra-prediction mode.
3. The intra-prediction method of claim 1 , wherein the aspect ratio of the rectangular video coding block is
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p
=
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longer
,
where L shorter and L longer are the lengths of the second and first sides of the rectangular video coding block, respectively.
4. The intra-prediction method of claim 1 , wherein the rectangular video coding block is a coding unit, a prediction unit, or a transform unit.
5. The intra-prediction method of claim 1 , wherein the conventional directional intra-prediction mode is applicable to both square video coding blocks and non-square rectangular video coding blocks, and wherein the extended directional intra-prediction mode is applicable to non-square rectangular video coding blocks.
6. The intra-prediction method of claim 5 , wherein the extended directional intra-prediction mode is not applicable to square video coding blocks.
7. An intra-prediction apparatus, comprising:
a non-transitory computer-readable storage medium storing instructions; and
one or more processors in communication with the non-transitory computer-readable storage medium, wherein the one or more processors are configured to execute the instructions to facilitate the following being performed by the apparatus:
obtaining a conventional directional intra-prediction mode based on signaled information;
determining an extended directional intra-prediction mode based on the conventional directional intra-prediction mode for a rectangular video coding block, wherein the rectangular video coding block has a first side and a second side, and wherein a length of the first side is greater than a length of the second side;
determining a plurality of available reference samples based on a direction of the extended directional intra-prediction mode; and
intra-predicting pixel values of pixels of the rectangular video coding block based on the plurality of available reference samples;
wherein the extended directional intra-prediction mode for the rectangular video coding block is determined further based on an aspect ratio of the rectangular video coding block.
8. The intra-prediction apparatus of claim 7 , wherein the extended directional intra-prediction mode for the rectangular video coding block is determined based on a mapping between the extended directional intra-prediction mode and the conventional directional intra-prediction mode.
9. The intra-prediction apparatus of claim 7 , wherein the aspect ratio of the rectangular video coding block is
R
a
s
p
=
L
s
h
o
r
t
e
r
L
longer
,
where L shorter and L longer are the lengths of the second and first sides of the rectangular video coding block, respectively.
10. The intra-prediction apparatus of claim 7 , wherein the conventional directional intra-prediction mode is applicable to both square video coding blocks and non-square rectangular video coding blocks, and wherein the extended directional intra-prediction mode is applicable to non-square rectangular video coding blocks.
11. The intra-prediction apparatus of claim 10 , wherein the extended directional intra-prediction mode is not applicable to square video coding blocks.
12. The intra-prediction apparatus of claim 7 , wherein the rectangular video coding block is a coding unit, a prediction unit, or a transform unit.
13. The intra-prediction apparatus of claim 7 , wherein the apparatus is a decoder.
14. A non-transitory computer readable medium having processor-executable instructions stored thereon for intra-prediction, wherein the processor-executable instructions, when executed, facilitate:
obtaining a conventional directional intra-prediction mode based on signaled information;
determining an extended directional intra-prediction mode based on the conventional directional intra-prediction mode for a rectangular video coding block, wherein the rectangular video coding block has a first side and a second side, and wherein a length of the first side is greater than a length of the second side;
determining a plurality of available reference samples based on a direction of the extended directional intra-prediction mode; and
intra-predicting pixel values of pixels of the rectangular video coding block based on the plurality of available reference samples;
wherein the extended directional intra-prediction mode for the rectangular video coding block is determined further based on an aspect ratio of the rectangular video coding block.
15. The non-transitory computer readable medium of claim 14 , wherein the extended directional intra-prediction mode for the rectangular video coding block is determined based on a mapping between the extended directional intra-prediction mode and the conventional directional intra-prediction mode.
16. The non-transitory computer readable medium of claim 14 , wherein the aspect ratio of the rectangular video coding block is
R
a
s
p
=
L
s
h
o
r
t
e
r
L
longer
,
where L shorter and L longer are the lengths of the second and first sides of the rectangular video coding block, respectively.
17. The non-transitory computer readable medium of claim 14 , wherein the conventional directional intra-prediction mode is applicable to both square video coding blocks and non-square rectangular video coding blocks, and wherein the extended directional intra-prediction mode is applicable to non-square rectangular video coding blocks.