Granted Patent B2

US 12,659,465 · App. 18/389,665 · Granted Jun 16, 2026

Inventors: Jonathan Pfaff (Berlin, DE); Philipp Helle (Berlin, DE); Dominique Maniry (Berlin, DE); Thomas Wiegand (Berlin, DE); Wojciech Samek (Berlin, DE); Stephan Kaltenstadler (Berlin, DE); Heiko Schwarz (Berlin, DE); Detlev Marpe (Berlin, DE); Mischa Siekmann (Berlin, DE); Martin Winken (Berlin, DE)

Assignee: Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.

H04N19/109H04N19/176H04N19/61

Abstract

Claims (69)

1 . A decoder configured to:

decode, from a data stream, a flag associated with a block, the flag having a first value specifies an intra-prediction mode for predicting the block is only from a first set of intra-prediction modes or having a second value specifies the intra-prediction mode for predicting the block is from a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

determine that the flag is the first value specifying that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes;

decode, from the data stream, an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

predict the block using the intra-prediction mode.

2 . The decoder of claim 1 , further configured to:

determine an intra-prediction signal for the block by using a set of samples neighboring the block and the intra-prediction mode.

3 . The decoder of claim 1 , further configured to:

decode the index using a variable length code; and

select the intra-prediction mode from the first set of intra-prediction modes based on the index.

4 . The decoder of claim 1 , further configured to:

identify a set of samples neighboring the block for predicting the block,

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is from the second set of intra-prediction modes, the set of neighboring samples are a one sample wide line extending alongside a left side and an upper side of the block; and

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes, the set of neighboring samples is at least two samples wide and forms an L-shape extending along the left side and the upper side of the block.

5 . A method for decoding a picture from a data stream, the method comprising:

decoding, from the data stream, a flag associated with a block of the picture, the flag having a first value specifies an intra-prediction mode for predicting the block is only from a first set of intra-prediction modes or having a second value specifies the intra-prediction mode for predicting the block is from a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

determining that the flag is the first value specifying that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes;

decoding, from the data stream, an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

predicting the block using the intra-prediction mode.

6 . The method of claim 5 , further comprising:

determining an intra-prediction signal for the block by using a set of samples neighboring the block and the intra-prediction mode.

7 . The method of claim 5 , further comprising:

decoding the index using a variable length code; and

selecting the intra-prediction mode from the first set of intra-prediction modes based on the index.

8 . The method of claim 5 , further comprising:

identifying a set of samples neighboring the block for predicting the block,

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is from the second set of intra-prediction modes, the set of neighboring samples is a one sample wide line extending alongside a left side and an upper side of the block; and

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes, the set of neighboring samples is at least two samples wide and forms an L-shape extending along the left side and the upper side of the block.

9 . A non-transitory, computer-readable medium storing instructions that, when executed by a processor of an electronic device, cause the electronic device to:

decode, from a data stream, a flag associated with a block, the flag having a first value specifies an intra-prediction mode for predicting the block is only from a first set of intra-prediction modes or having a second value specifies the intra-prediction mode for predicting the block is from a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

determine that the flag is the first value specifying that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes;

decode, from the data stream, an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

predict the block using the intra-prediction mode.

10 . The non-transitory, computer-readable medium of claim 9 , further containing instructions that when executed cause the processor to:

determine an intra-prediction signal for the block by using a set of samples neighboring the block and the intra-prediction mode.

11 . The non-transitory, computer-readable medium of claim 9 , further containing instructions that when executed cause the processor to:

decode the index using a variable length code; and

select the intra-prediction mode from the first set of intra-prediction modes based on the index.

12 . The non-transitory, computer-readable medium of claim 9 , further containing instructions that when executed cause the processor to:

identify a set of samples neighboring the block for predicting the block,

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is from the second set of intra-prediction modes, the set of neighboring samples is a one sample wide line extending alongside a left side and an upper side of the block; and

wherein in response to the flag indicating that the intra-prediction mode for predicting the block is only from the first set of intra-prediction modes, the set of neighboring samples is at least two samples wide and forms an L-shape extending along the left side and the upper side of the block.

13 . An encoder configured to:

determine whether an intra-prediction mode for encoding a block is from a first set of intra-prediction modes or a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

encode a flag associated with the block, the flag having a first value or a second value, the first value specifying that the determined intra-prediction mode for encoding the block is only from the first set of intra-prediction modes, the second value specifying that the determined intra-prediction mode for encoding the block is from the second set of intra-prediction modes;

in response to the determination that the intra-prediction mode for encoding the block is from the first set of intra-prediction modes, encode an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

encode the block using the intra-prediction mode from the first set of intra-prediction modes when the flag has the first value.

14 . A method for encoding a picture, the method comprising:

determining whether an intra-prediction mode for encoding a block of the picture is from a first set of intra-prediction modes or a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

encoding a flag associated with the block, the flag having a first value or a second value, the first value specifying that the determined intra-prediction mode for encoding the block is only from the first set of intra-prediction modes, the second value specifying that the determined intra-prediction mode for encoding the block is from the second set of intra-prediction modes;

in response to determining that the intra-prediction mode for encoding the block is from the first set of intra-prediction modes, encoding an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

encoding the block using the intra-prediction mode from the first set of intra-prediction modes when the flag has the first value.

15 . A non-transitory, computer-readable medium storing instructions that, when executed by a processor of an electronic device, cause the electronic device to:

determine whether an intra-prediction mode for encoding a block is from a first set of intra-prediction modes or a second set of intra-prediction modes, wherein:

the first set of intra-prediction modes does not include any angular modes, DC modes, or planar modes, and

the second set of intra-prediction modes includes a DC mode and at least one angular mode; and does not include any intra-prediction modes included in the first set of intra-prediction modes;

encode a flag associated with the block, the flag having a first or a second value, the first value specifying that the determined intra-prediction mode for encoding the block is only from the first set of intra-prediction modes, the second value specifying that the determined intra-prediction mode for encoding the block is from the second set of intra-prediction modes;

in response to the determination that the intra-prediction mode for encoding the block is from the first set of intra-prediction modes, encode an index indicating the intra-prediction mode from the first set of intra-prediction modes; and

encode the block using the intra-prediction mode from the first set of intra-prediction modes when the flag has the first value.

Assignments (1)

Priority Claims (1)

Continuity (4)

References Cited (23)