Method of predicting motion vectors in video codec in which multiple references are allowed, and motion vector encoding/decoding apparatus using the same

• US 9,344,740 B2
• Filed: 03/12/2015
• Issued: 05/17/2016
• Est. Priority Date: 05/26/2010
• Status: Active Grant

• Current Assignee: Hangzhou Hikvision Digital Technology Company Limited
• Original Assignee: Newracom Inc.
• Inventors: Jeong, Je Chang, Jin, Soon Jong, Park, Sang Jun, Lee, Hyuk
• Primary Examiner(s): Kelley, Christopher S
• Assistant Examiner(s): PICON-FELICIANO, ANA J
• Application Number:
  US14/645,911
• Publication Number:
  US 20150189308A1
• Time in Patent Office: 432 Days
• Field of Search: 375/240.16, 375/E7.027, 375/E7.125
• US Class Current: 1/1
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/513 Processing of motion vectors
• CPC Class Codes: H04N 19/52 by predictive encoding
• CPC Class Codes: H04N 19/527 Global motion vector estimation
• CPC Class Codes: H04N 19/55 Motion estimation with spatial constraints, e.g. at image or region borders
• CPC Class Codes: H04N 19/573 Motion compensation with multiple frame prediction using two or more reference frames in a given prediction direction

Abstract

Initial value is selected when motion estimation is performed using predicted motion vector in video codec in which multiple references are allowed, and coding amount of motion vectors is reduced using predicted motion vector. Motion vector encoding apparatus includes predicted motion vector generator that generates adjacent motion vectors of current block with respect to each of reference pictures and generates each predicted motion vector of the current block from the generated adjacent motion vectors, motion estimator that determines final motion vector of the current block and final reference picture corresponding to the final motion vector with regard to search regions of the reference pictures, differential unit that obtains difference between the final motion vector of the current block and final predicted motion vector corresponding to the determined final reference picture among the predicted motion vectors, and unit for encoding information about the final reference picture and the difference.

Claims

1. A decoding method of a decoding device, comprising:

decoding, by the decoding device, an input bitstream to generate a motion vector difference for a current block;

obtaining, by the decoding device, motion vectors of neighboring blocks of the current block, wherein the motion vectors correspond to neighboring blocks respectively, the neighboring blocks and the current block are in a current picture, and the motion vectors of the neighboring blocks are used to decode the respective neighboring blocks according to respective reference pictures of the neighboring blocks;

generating, by the decoding device, interpolated motion vectors, wherein each of the interpolated motion vectors is generated by interpolating a motion vector of a corresponding neighboring block of the current block based on a distance between a reference picture of the corresponding neighboring block and the current picture and a distance between a reference picture of the current block and the current picture, wherein the reference picture of the corresponding neighboring block is different from the reference picture of the current block;

predicting, by the decoding device, a motion vector of the current block based on the interpolated motion vectors to generate a predicted motion vector; and

generating, by the decoding device, a motion vector of the current block by using the predicted motion vector.

2. The decoding method of claim 1, further comprising:

performing, by the decoding device, a motion compensating by using the motion vector of the current block to generate a motion compensated block of the current block; and

adding, by the decoding device, a residual block of the current block and the motion compensated block of the current block to reconstruct the current block.

3. The decoding method of claim 1, wherein at least one of the neighboring blocks is formed in a rectangular shape by asymmetric partition.

4. The decoding method of claim 1, wherein the decoding method is applied to a video coding scheme in which multiple references are allowed.

5. The decoding method of claim 1, wherein generating the interpolated motion vectors comprises:

generating each of the interpolated motion vectors by interpolating a motion vector of a corresponding neighboring block based on a distance between a reference picture of the corresponding neighboring block and the current picture and a distance between the reference picture of the current block and the current picture when the distance between the reference picture of the corresponding neighboring block and the current picture is equal to or greater than the distance between the reference picture of the current block and the current picture.

6. The decoding method of claim 1, wherein at least one of the neighboring blocks is one of a left block, an upper block, and a right upper block of the current block.

7. The decoding method of claim 1, wherein one of the neighboring blocks is a left block of the current block, and another of the neighboring blocks is one of an upper block and a right upper block of the current block.

8. The decoding method of claim 1, wherein predicting the motion vector of the current block comprises:

selecting one among the interpolated motion vectors as the predicted motion vector.

9. The decoding method of claim 8, wherein selecting one among the interpolated motion vectors comprises:

selecting a median value among the interpolated motion vectors as the predicted motion vector.

10. A decoding device, comprising:

a decoder configured to decode an input bitstream to generate a motion vector difference for a current block;

a predicted motion vector generator configured to obtain motion vectors of neighboring blocks of the current block, wherein the motion vectors correspond to neighboring blocks respectively, the neighboring blocks and the current block are in a current picture, and the motion vectors of the neighboring blocks are used to decode the respective neighboring blocks according to respective reference pictures of the neighboring blocks, generate interpolated motion vectors, wherein each of the interpolated motion vectors is generated by interpolating a motion vector of a corresponding neighboring block based on a distance between a reference picture of the corresponding neighboring block and the current picture and a distance between a reference picture of the current block and the current picture, and predict a motion vector of the current block based on the interpolated motion vectors to generate a predicted motion vector, wherein the reference picture of the corresponding neighboring block is different from the reference picture of the current block; and

a first adder configured to generate a motion vector of the current block by using the predicted motion vector.

11. The decoding device of claim 10, further comprising:

a motion compensator configured to perform a motion compensating by using the motion vector of the current block to generate a motion compensated block of the current block; and

a second adder configured to add a residual block of the current block and the motion compensated block of the current block to reconstruct the current block.

12. The decoding device of claim 10, wherein at least one of the neighboring blocks is formed in a rectangular shape by asymmetric partition.

13. The decoding device of claim 10, wherein the decoding method is applied to a video coding scheme in which multiple references are allowed.

14. The decoding device of claim 10, wherein the predicted motion vector generator is configured to generate each of the interpolated motion vectors by interpolating the motion vector of the corresponding neighboring block based on the distance between the reference picture of the corresponding neighboring block and the current picture and the distance between the reference picture of the current block and the current picture when the distance between the reference picture of the corresponding neighboring block and the current picture is equal to or greater than the distance between the reference picture of the current block and the current picture.

15. The decoding device of claim 10, wherein at least one of the neighboring blocks is one of a left block, an upper block, and a right upper block of the current block.

16. The decoding device of claim 10, wherein one of the neighboring blocks is a left block of the current block, and another of the neighboring blocks is one of an upper block and a right upper block of the current block.

17. The decoding device of claim 10, wherein the predicted motion vector generator is configured to select one among the interpolated motion vectors as the predicted motion vector.

18. The decoding device of claim 17, wherein the predicted motion device generator is configured to select a median value among the interpolated motion vectors as the predicted motion vector.

19. An encoding method of an encoding device, comprising:

obtaining, by the encoding device, motion vectors of neighboring blocks of a current block, wherein the motion vectors correspond to neighboring blocks respectively, the neighboring blocks and the current block are in a current picture, and the motion vectors of the neighboring blocks are used to encode the respective neighboring blocks according to respective reference pictures of the neighboring blocks;

generating, by the encoding device, interpolated motion vectors, wherein each of the interpolated motion vectors is generated by interpolating a motion vector of a corresponding neighboring block based on a distance between a reference picture of the corresponding neighboring block and the current picture and a distance between a reference picture of the current block and the current picture, wherein the reference picture of the corresponding neighboring block is different from the reference picture of the current block;

predicting, by the encoding device, a motion vector of the current block based on the interpolated motion vectors to generate a predicted motion vector; and

generating, by the encoding device, a motion vector of the current block; and

encoding, by the encoding device, a difference between the motion vector of the current block and the predicted motion vector.

20. The encoding method of claim 19, wherein at least one of the neighboring blocks is one of a left block, an upper block, and a right upper block of the current block.