Signaling of down-sampling location information in scalable video coding

Patent metadata

Field	Value
Publication number	US-10448032-B2
Application number	US-201314017169-A
Country	US
Kind code	B2
Filing date	Sep 3, 2013
Priority date	Sep 4, 2012
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

Methods and systems for video image coding are provided. Sets of filters may be selected and applied to video information at least partially based on phase displacement information between a first and second layer of video information. For example, the phase displacement information may correspond to a difference between a position of a pixel in the first layer and a corresponding position of the pixel in the second layer. The selected filter set can be an up-sampling filter or a down-sampling filter. The phase displacement information may be encoded as a syntax element embedded in the video bit stream.

First claim

What is claimed is:

1. A device configured to code video information, the device comprising:
a memory configured to store video data, the video data comprising a first layer of video information; and
a processor in communication with the memory, the processor configured to:
signal or receive a binary down-sampling indicator indicative of a down-sampling scheme and having one of a first down-sampling indicator value and a second down-sampling indicator value, wherein the binary down-sampling indicator having the first down-sampling indicator value indicates that (a) a zero-phase down-sampling scheme of two predefined down-sampling schemes is to be used and (b) sample locations in a second layer of video information and sample locations in the first layer have a zero-phase relationship, and the binary down-sampling indicator having the second down-sampling indicator value indicates that (c) a symmetric down-sampling scheme of the two predefined down-sampling schemes that is different from the zero-phase down-sampling scheme is to be used and (d) the sample locations in the second layer and the sample locations in the first layer have a symmetric-phase relationship;
perform one of: (i) based on a determination that the binary down-sampling indicator has the first down-sampling indicator value, select a position mapping method specific to the zero-phase down-sampling scheme, or (ii) based on a determination that the binary down-sampling indicator has the second down-sampling indicator value, select a position mapping method specific to the symmetric down-sampling scheme that is different from the position mapping method specific to the zero-phase down-sampling scheme; and
generate a modified version of the first layer using the selected position mapping method.

2. The device of claim 1 , wherein:
the first layer comprises a base layer;
the second layer comprises an enhancement layer; and
the processor is further configured to receive the indication as a syntax element and generate the modified version of the first layer using an up-sampling image filter.

3. The device of claim 1 , wherein:
the first layer comprises an enhancement layer;
the second layer comprises a base layer; and
the processor is further configured to signal the indication as a syntax element and generate the modified version of the first layer using a down-sampling image filter.

4. The device of claim 1 , wherein the processor is further configured to signal or receive an offset value indicative of a difference between (i) a position of a pixel in the first layer calculated according to the position mapping method specific to the zero-phase down-sampling scheme and (ii) a position of the pixel in the first layer calculated according to the position mapping method specific to the symmetric down-sampling scheme.

5. The device of claim 1 , wherein the indication comprises a binary value that indicates one of the zero-phase relationship or the symmetric-phase relationship between the first layer and the second layer.

6. The device of claim 1 , wherein the indication comprises a first syntax element indicating whether horizontal sample locations are symmetric and a second syntax element indicating whether vertical sample locations are symmetric.

7. The device of claim 1 , wherein the indication indicates that the sample locations in the second layer and the sample locations in the first layer have a zero-phase relationship having a zero-phase shift in both vertical and horizontal directions.

8. The device of claim 1 , wherein the processor is further configured to:
select an image filter for generating the modified version of the first layer from a default image filter set, if the indication is not signaled or received; and
select the image filter for generating the modified version of the first layer from another image filter set based on the indication, if the indication is signaled or received.

9. The device of claim 8 , wherein the default image filter set is based at least in part on the symmetric-phase relationship between the first layer and the second layer.

10. The device of claim 8 , wherein the default image filter set is based at least in part on the zero-phase relationship between the first layer and the second layer.

11. The device of claim 1 , wherein the indication comprises alignment information.

12. The device of claim 11 , wherein the alignment information is modeled as a function mapping x pixel coordinates and y pixel coordinates to phase offsets.

13. The device of claim 1 , wherein the processor is further configured to signal or receive coefficients of an image filter to be used for generating the modified version of the first layer.

14. The device of claim 1 , wherein the processor is configured to select an image filter for generating the modified version of the first layer from an image filter set comprising coefficients {0, 0, 0, 64, 0, 0, 0, 0} for a phase shift of zero, {0, 1, −3, 63, 4, −2, 1, 0} for a phase shift of one, {0, 2, −6, 61, 9, −3, 1, 0} for a phase shift of two, {−1, 3, −8, 60, 13, −4, 1, 0} for a phase shift of three, {−1, 4, −10, 58, 17, −5, 1, 0} for a phase shift of four, {−1, 4, −11, 53, 25, −8, 3, −1} for a phase shift of five, {−1, 4, −11, 50, 29, −9, 3, −1} for a phase shift of six, {−1, 4, −11, 45, 34, −10, 4, −1} for a phase shift of seven, {−1, 4, −11, 40, 40, −11, 4, −1} for a phase shift of eight, {−1, 4, −10, 34, 45, −11, 4, −1} for a phase shift of nine, {−1, 3, −9, 29, 50, −11, 4, −1} for a phase shift of ten, {−1, 3, −8, 25, 53, −11, 4, −1} for a phase shift of eleven, {0, 1, −5, 17, 58, −10, 4, −1} for a phase shift of twelve, {0, 1, −4, 13, 60, −8, 3, −1} for a phase shift of thirteen, {0, 1, −3, 8, 62, −6, 2, 0} for a phase shift of fourteen, and {0, 1, −2, 4, 63, −3, 1, 0} for a phase shift of fifteen.

15. The device of claim 1 , wherein the processor is configured to select an image filter for generating the modified version of the first layer from an image filter set comprising coefficients {0, 64, 0, 0} for a phase shift of zero, {−2, 62, 4, 0} for a phase shift of one, {−2, 58, 10, −2} for a phase shift of two, {−4, 56, 14, −2} for a phase shift of three, {−4, 54, 16, −2} for a phase shift of four, {−6, 52, 20, −2} for a phase shift of five, {−6, 48, 26, −4} for a phase shift of six, {−4, 42, 30, −4} for a phase shift of seven, {−4, 36, 36, −4} for a phase shift of eight, {−4, 30, 42, −4} for a phase shift of nine, {−4, 26, 48, −6} for a phase shift of ten, {−2, 20, 52, −6} for a phase shift of eleven, {−2, 16, 54, −4} for a phase shift of twelve, {−2, 14, 56, −4} for a phase shift of thirteen, {−2, 10, 58, −2} for a phase shift of fourteen, and {0, 4, 62, −2} for a phase shift of fifteen.

16. The device of claim 1 , wherein the device is selected from the group consisting of a desktop computer, a notebook computer, a tablet computer, a set-top box, a telephone handset, a television, a camera, a display device, a digital media player, a video gaming console, and a video streaming device that comprises the memory and the processor.

17. A method of decoding video information, comprising:
obtaining a base layer of video information;
receiving a binary down-sampling indicator indicative of a down-sampling scheme and having one of a first down-sampling indicator value and a second down-sampling indicator value, wherein the binary down-sampling indicator having the first down-sampling indicator value indicates that (a) a zero-phase down-sampling scheme of two predefined down-sampling schemes is to be used and (b) sample locations in the base layer and

Assignees

• Qualcomm Inc

Inventors

• Chen Jianle
• Guo Liwei
• Li Xiang
• Karczewicz Marta
• Pu Wei

Classifications

• H04N19/187

  the unit being a scalable video layer · CPC title

• H04N19/30 Primary

  using hierarchical techniques, e.g. scalability (H04N19/63 takes precedence) · CPC title

• H04N19/33

  in the spatial domain · CPC title

• H04N19/117 Primary

  Filters, e.g. for pre-processing or post-processing (sub-band filter banks H04N19/635) · CPC title