Temporal tile staggering for block based video compression

• US 20010022815A1
• Filed: 05/18/2001
• Published: 09/20/2001
• Est. Priority Date: 05/26/1995
• Status: Active Grant

• Current Assignee: Rohit Agarwal
• Original Assignee: Rohit Agarwal
• Inventors: Agarwal, Rohit
• Granted Patent: US 6,473,463 B2
• Time in Patent Office: Days
• US Class Current: 375/240.16
• CPC Class Codes: H04N 19/119 Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/85 using pre-processing or post-processing specially adapted for video compression

Abstract

In block based video compression, a frame is divided into blocks which define a tiling pattern. The tiling pattern is varied from frame-to-frame to prevent an accumulation of errors which tend to appear at tile edges and can increase over time when using block-based compression. In a preferred embodiment, a normal frame is padded by a border all around the normal frame size. The padding is operable to extend any blocks around the periphery of the image frame which might be smaller in dimension than the standard blocks, such as those within the interior of the frame, such that they can be treated by the block-based compression systems as full size blocks.

Claims

1. A computer-implemented process for encoding images, comprising the steps of:

(a) receiving a first image;

(b) dividing the first image into a plurality of blocks using a first tiling pattern;

(c) encoding the blocks of the first image to generate encoded signals for the first image;

(d) receiving a second image;

(e) dividing the second image into a plurality of blocks using a second tiling pattern different from the first tiling pattern; and

(f) encoding the blocks of the second image to generate encoded signals for the second image.

2. The process of

claim 1

, wherein step (c) comprises the step of encoding the blocks of the first image using motion estimation.

3. The process of

claim 1

, wherein step (c) comprises the step of encoding the blocks of the first image using a block based transform.

4. The process of

claim 1

, wherein at least two of the blocks of the blocks of the first image are of different size.

5. The process of

claim 1

, wherein step (b) comprises the steps of:

(1) padding the first image to generate a first padded frame; and

(2) dividing the first padded frame into the plurality of blocks of the first image.

6. The process of

claim 5

, wherein the blocks of the first image are of equal size.

7. The process of

claim 5

, wherein step (b)(1) comprises the step of replicating pixels around a periphery of the first image.

8. The process of

claim 1

, wherein step (c) further comprises the step of encoding the first tiling pattern into the encoded signals for the first image.

9. An apparatus for encoding images, comprising:

(a) means for receiving a first image;

(b) means for dividing the first image into a plurality of blocks using a first tiling pattern;

(c) means for encoding the blocks of the first image to generate encoded signals for the first image;

(d) means for receiving a second image;

(e) means for dividing the second image into a plurality of blocks using a second tiling pattern different from the first tiling pattern; and

(f) means for encoding the blocks of the second image to generate encoded signals for the second image.

10. The apparatus of

claim 9

, wherein means (c) encodes the blocks of the first image using motion estimation.

11. The apparatus of

claim 9

, wherein means (c) encodes the blocks of the first image using a block based transform.

12. The apparatus of

claim 9

, wherein means (b) divides at least two of the blocks of the blocks of the first image into blocks of different size.

13. The apparatus of

claim 9

, wherein means (b):

(1) pads the first image to generate a first padded frame; and

(2) divides the first padded frame into the plurality of blocks of the first image.

14. The apparatus of

claim 13

, wherein the blocks of the first image are of equal size.

15. The apparatus of

claim 13

, wherein means (b) replicates pixels around a periphery of the first image.

16. The apparatus of

claim 9

, wherein means (c) encodes the first tiling pattern into the encoded signals for the first image.

17. A computer-implemented process for decoding images which have been encoded using one or more tiling patterns, comprising the steps of:

(a) receiving encoded signals of a first image;

(b) decoding the received encoded signals of the first image based on a first tiling pattern to generate a decoded first image;

(c) receiving encoded signals of a second image; and

(d) decoding the received encoded signals of the second image based on a second tiling pattern different from the first tiling pattern to generate a decoded second image.

18. The process of

claim 17

, wherein step (b) comprises the step of decoding the signals of the first image using motion compensation.

19. The process of

claim 17

, wherein step (b) comprises the step of decoding the signals of the first image using an inverse block based transform.

20. The process of

claim 17

, wherein the first tiling pattern is comprised of blocks and wherein at least two of the blocks of the first image are of different size.

21. The process of

claim 17

, wherein the first tiling pattern is comprised of blocks of equal size.

22. The process of

claim 21

, wherein step (b) further comprises the step of deleting signals from the encoded signals of the first image to remove padding from the decoded first image.

23. The process of

claim 22

, wherein deletion of the signals deletes pixels around a periphery of the first image.

24. The process of

claim 17

, wherein the encoded signal of the first image comprise the first tiling pattern and step (b) further comprises the step of decoding the encoded signals to determine the first tiling pattern.

25. An apparatus for decoding images comprising:

(a) means for receiving encoded signals of a first image;

(b) means for decoding the received encoded signals of the first image based on a first tiling pattern to generate a decoded first image;

(c) means for receiving encoded signals of a second image; and

(d) means for decoding the received encoded signals of the second image based on a second tiling pattern different than the first tiling pattern to generate a decoded second image.

26. The apparatus of

claim 25

, wherein means (b) decodes the signals of the first image using motion compensation.

27. The apparatus of

claim 25

, wherein means (b) decodes the signals of the first image using an inverse block based transform.

28. The apparatus of

claim 25

, wherein the first tiling pattern is comprised of blocks of different size.

29. The apparatus of

claim 25

, wherein the first tiling pattern is comprised of blocks of equal size.

30. The apparatus of

claim 29

, wherein means (b) deletes signals from the encoded signals of the first image to remove padding from the decoded first image.

31. The apparatus of

claim 30

, wherein means (b) deletes pixels around a periphery of the decoded first image.

32. The apparatus of

claim 25

, wherein the encoded signals of the first image comprise the first tiling pattern and means (b) decodes the encoded signals to determine the first tiling pattern.