APPARATUS, A METHOD AND A COMPUTER PROGRAM FOR VIDEO CODING AND DECODING

• US 20130342644A1
• Filed: 06/13/2013
• Published: 12/26/2013
• Est. Priority Date: 06/20/2012
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Hannuksela, Miska Matias, Rusanovskyy, Dmytro
• Granted Patent: US 9,998,726 B2
• Time in Patent Office: Days
• US Class Current: 348/43
• CPC Class Codes: H04N 13/161 Encoding, multiplexing or demultiplexing different image signal components for multi-view video sequence encoding H04N19/597
• CPC Class Codes: H04N 19/42 characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/597 specially adapted for multi-view video sequence encoding

Abstract

There is disclosed a method, apparatus and computer program product in which a view synthesis prediction utilizes a depth map, disparity information or other ranging information of a co-located reference frame in another view. A first uncompressed texture block of a first texture picture representing a first view and ranging information associated with the first uncompressed texture block are obtained. Disparity information with reference to a second view is derived on the basis of the ranging information. Reference samples of the second view are obtained on the basis of the disparity information. A view synthesis prediction is performed by using the reference samples to obtain a reference block for encoding the first uncompressed texture block.

Claims

1. A method comprising:

obtaining a first texture block of a first texture picture representing a first view;

obtaining ranging information associated with the first texture block;

deriving disparity information with reference to a reference picture in a second view on the basis of the ranging information;

obtaining reference samples of the second view on the basis of the disparity information to obtain a reference block for performing at least one of the following;

encoding the first texture block;

decoding the first texture block.

2. The method according to claim 1 comprising

deriving disparity information with reference to a second reference picture in a third view on the basis of the ranging information;

obtaining reference samples of the third view on the basis of the disparity information;

using the reference samples of the second view and the reference samples of the third view to obtain the reference block.

3. The method according to claim 1 comprising deriving disparity information to specify spatial coordinates offset between samples of the first texture block and the reference samples.

4. The method according to claim 1, comprising:

using the disparity information for locating the reference samples in the reference picture;

obtaining reference sample values for the reference block on the basis of the located reference samples;

filtering the reference sample values;

filtering the reference sample values using one or more weighted prediction parameters.

5. The method according to claim 1 comprising providing at least a first reference picture list indicative of pictures used as reference pictures from which the reference block is selected.

6. The method according to claim 1 wherein obtaining ranging information comprises at least one of the following:

reconstructing or decoding a first decoded depth picture representing the first view and obtaining said ranging information from the first decoded depth picture;

obtaining said ranging information from depth pictures preceding the first texture picture in coding order;

obtaining said ranging information from texture blocks preceding the first texture block in coding order.

7. The method according to claim 1 further comprising processing of the ranging information or the disparity information in at least one of the following ways:

filtering the ranging information or the disparity information;

subsampling the ranging information or the disparity information;

deriving one disparity value from the ranging information or the disparity information.

8. An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus to:

obtain a first texture block of a first texture picture representing a first view;

obtain ranging information associated with the first texture block;

derive disparity information with reference to a reference picture in a second view on the basis of the ranging information;

obtain reference samples of the second view on the basis of the disparity information to obtain a reference block for performing at least one of the following;

encoding the first texture block;

decoding the first texture block.

9. The apparatus according to claim 8 said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to

derive disparity information with reference to a second reference picture in a third view on the basis of the ranging information;

obtain reference samples of the third view on the basis of the disparity information;

use the reference samples of the second view and the reference samples of the third view to obtain the reference block.

10. The apparatus according to claim 8, said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to derive disparity information to specify spatial coordinates offset between samples of the first texture block and the reference samples.

11. The apparatus according to claim 8, said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to:

use the disparity information for locating the reference samples in the reference picture;

obtain the reference sample values on the basis of the located reference samples;

filter the reference sample values; and

filter the reference sample values using one or more weighted prediction parameters.

12. The apparatus according to claim 8, said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to provide at least a first reference picture list indicative of pictures used as reference pictures from which the reference block is selected.

13. The apparatus according to claim 8, said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to:

reconstruct or decode a first decoded depth picture representing the first view and obtain said ranging information from the first decoded depth picture;

obtain said ranging information from depth pictures preceding the first texture picture in coding order;

obtain said ranging information from texture blocks preceding the first texture block in coding order.

14. The apparatus according to claim 8, said at least one memory stored with code thereon, which when executed by said at least one processor, further causes the apparatus to process of the ranging information or the disparity information in at least one of the following ways:

filtering the ranging information or the disparity information;

subsampling the ranging information or the disparity information;

deriving one disparity value from the ranging information or the disparity information.

15. A computer program product including one or more sequences of one or more instructions which, when executed by one or more processors, cause an apparatus to at least perform the following:

obtain a first texture block of a first texture picture representing a first view;

obtain ranging information associated with the first texture block;

derive disparity information with reference to a reference picture in a second view on the basis of the ranging information;

obtain reference samples of the second view on the basis of the disparity information to obtain a reference block for performing at least one of the following;

encoding the first texture block;

decoding the first texture block.

16. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to

derive disparity information with reference to a second reference picture in a third view on the basis of the ranging information;

obtain reference samples of the third view on the basis of the disparity information;

use the reference samples of the second view and the reference samples of the third view to obtain the reference block.

17. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to derive disparity information to specify spatial coordinates offset between samples of the first texture block and the reference samples.

18. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to:

use the disparity information for locating reference samples in the reference picture;

obtain the reference sample values on the basis of the located reference samples;

filter the reference sample values; and

filter the reference sample values using one or more weighted prediction parameters.

19. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to provide at least a first reference picture list indicative of pictures used as reference pictures from which the reference block is selected.

20. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to:

reconstruct or decode a first decoded depth picture representing the first view and obtain said ranging information from the first decoded depth picture;

obtain said ranging information from depth pictures preceding the first texture picture in coding order;

obtain said ranging information from texture blocks preceding the first texture block in coding order.

21. The computer program product according to claim 15 including one or more sequences of one or more instructions which, when executed by one or more processors, cause the apparatus to process of the ranging information or the disparity information in at least one of the following ways:

filtering the ranging information or the disparity information;

subsampling the ranging information or the disparity information;

deriving one disparity value from the ranging information or the disparity information.

22. A video encoder configured for:

obtaining a first texture block of a first texture picture representing a first view;

obtaining ranging information associated with the first texture block;

deriving disparity information with reference to a reference picture in a second view on the basis of the ranging information;

obtaining reference samples of the second view on the basis of the disparity information to obtain a reference block for encoding the first texture block.