INTRA PREDICTION WITH ADAPTIVE INTERPOLATION FILTERING FOR IMAGE COMPRESSION

• US 20100111431A1
• Filed: 11/05/2008
• Published: 05/06/2010
• Est. Priority Date: 11/05/2008
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Gharavi-Alkhansari, Mohammad, Tabatabai, Ali
• Granted Patent: US 8,774,541 B2
• Time in Patent Office: Days
• US Class Current: 382/236
• 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 19/117 Filters, e.g. for pre-processing or post-processing sub-band filter banks H04N19/635
• CPC Class Codes: H04N 19/14 Coding unit complexity, e.g. amount of activity or edge presence estimation H04N19/146 takes precedence
• 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

Abstract

A method and apparatus for adaptive interpolation filtering for image compression is disclosed. The method includes determining an activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction, and selecting a filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

Claims

1. A method comprising:

determining at least one of an (i) activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or (ii) a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction; and

selecting a filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

2. The method of claim 1, wherein selecting a filter comprises selecting, in accordance with the at least one of the activity measure or the distance measure, at least one coefficient of the filter.

3. The method of claim 1, wherein the set of pixels comprises:

at least one previously encoded pixel reconstructed at a time prior to determining the at least one of the activity measure or the distance measure.

4. The method of claim 1, wherein determining the at least one of the activity measure or the distance measure comprises any of:

calculating a variance of the set of pixels;

calculating an amount of noise in the set of pixels;

calculating a standard deviation of the set of pixels; and

calculating a sum of absolute difference of the set of pixels with the average of the set of pixels.

5. The method of claim 1, wherein the filter is selected from a set of predefined filters, and wherein at least one predefined filter of the set of predefined filters operates to filter the at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

6. The method of claim 1, further comprising:

filtering the at least a portion of the set of pixels using the filter.

7. An apparatus for selecting a filter for intraframe prediction, the apparatus comprising:

a processor for executing an adaptive filtering module for selecting a filter for intraframe prediction.

8. The apparatus of claim 7, wherein the adaptive filtering module operates to:

determine at least one of an activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction; and

select the filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

9. The apparatus of claim 8, wherein at least one coefficient of the filter is selected in accordance with the at least one of the activity measure or the distance measure.

10. The apparatus of claim 8, wherein the set of pixels comprises:

at least one pixel reconstructed at a time prior to determining the at least one of the activity measure or the distance measure.

11. The apparatus of claim 8, wherein the activity measure comprises any of:

a variance of the set of pixels;

an amount of noise in the set of pixels;

a standard deviation of the set of pixels; and

a sum of absolute difference of the set of pixels with the average of the set pixels.

12. The apparatus of claim 8, wherein the filter is selected from a set of predefined filters, and wherein at least one predefined filter of the set of predefined filters operates to filter the at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

13. A computer-readable medium having stored thereon a plurality of instructions, the plurality of instructions including instructions which, when executed by a processor, cause the processor to:

determine at least one of an activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction; and

select a filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

14. The computer-readable medium of claim 13, wherein at least one coefficient of the filter is selected in accordance with the at least one of the activity measure or the distance measure.

15. The computer-readable medium of claim 13, wherein the set of pixels comprises:

at least one pixel reconstructed at a time prior to determining the at least one of the activity measure or the distance measure.

16. The computer-readable medium of claim 13, wherein determining the activity measure comprises any of:

calculating a variance of the set of pixels;

calculating an amount of noise in the set of pixels;

calculating a standard deviation of the set of pixels; and

calculating a sum of absolute difference of the set of pixels with the average of the set pixels.

17. The computer-readable medium of claim 13, wherein the filter is selected from a set of predefined filters, and wherein at least one predefined filter of the set of predefined filters operates to filter the at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure.

18. A system comprising:

a memory operable to store and receive requests to obtain programmable instructions to;

determine at least one of an activity measure associated with a set of pixels neighboring a pixel undergoing intraframe prediction or a distance measure between at least one pixel in the set of pixels and the pixel undergoing intraframe prediction; and

select a filter for filtering at least a portion of the set of pixels in accordance with the at least one of the activity measure or the distance measure; and

a processor operable to obtain the from the memory and execute the executable instructions

19. The system of claim 18, wherein the memory is operable to store at least one coefficient of the filter for selection in accordance with the at least one of the activity measure or the distance measure.

20. The system of claim 18, wherein the set of pixels comprises:

at least one pixel reconstructed at a time prior to determining the at least one of the activity measure or the distance measure.