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

• US 9,344,739 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:
  US14/645,868
• Publication Number:
  US 20150189307A1
• 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;

interpolating, by the decoding device, a motion vector of a first neighboring block of the current block based on a first distance and a second distance to generate a first interpolated motion vector, wherein the first neighboring block and the current block are in a current picture, the first distance is a distance between a reference picture of the first neighboring block and the current picture, the second distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the first neighboring block is used to decode the first neighboring block according to the reference picture of the first neighboring block, wherein the reference picture of the first neighboring block is different from the reference picture of the current block;

interpolating, by the decoding device, a motion vector of a second neighboring block of the current block based on a third distance and a fourth distance to generate a second interpolated motion vector, wherein the second neighboring block is in the current picture, the third distance is a distance between a reference picture of the second neighboring block and the current picture, the fourth distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the second neighboring block is used to decode the second neighboring block according to the reference picture of the second neighboring block, wherein the reference picture of the second 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 first interpolated motion vector and the second interpolated motion vector to generate a predicted motion vector; and

adding, by the decoding device, the predicted motion vector and the motion vector difference to generate the motion vector of the current block.

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 first neighboring block and the second neighboring block is formed in a rectangular shape by asymmetric partition.

4. The decoding method of claim 1, wherein interpolating the motion vector of the first neighboring block comprises:

interpolating the motion vector of the first neighboring block of the current block based on the first distance and the second distance to generate the first interpolated motion vector, when the first distance is equal to or greater than the second distance.

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

6. The decoding method of claim 1, wherein the second neighboring block 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 the first neighboring block is a left block of the current block, and the second neighboring block 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 a plurality of interpolated motion vectors including the first interpolated motion vector and the second interpolated motion vector as the predicted motion vector.

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

selecting a median value among the plurality of the interpolated motion vectors including the first interpolated motion vector and the second interpolated motion vector 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 prediction motion vector generator configured to;

interpolate a motion vector of a first neighboring block of the current block based on a first distance and a second distance to generate a first interpolated motion vector, wherein the first neighboring block and the current block are in a current picture, the first distance is a distance between a reference picture of the first neighboring block and the current picture, the second distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the first neighboring block is used to decode the first neighboring block according to the reference picture of the first neighboring block, wherein the reference picture of the first neighboring block is different from the reference picture of the current block;

interpolate a motion vector of a second neighboring block of the current block based on a third distance and a fourth distance to generate a second interpolated motion vector, wherein the second neighboring block is in the current picture, the third distance is a distance between a reference picture of the second neighboring block and the current picture, the fourth distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the second neighboring block is used to decode the second neighboring block according to the reference picture of the second neighboring block, wherein the reference picture of the second neighboring block is different from the reference picture of the current block, and

predict a motion vector of the current block based on the first interpolated motion vector and the second interpolated motion vector to generate a predicted motion vector; and

a first adder configured to add the predicted motion vector and the motion vector difference to generate the motion vector of the current block.

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 first neighboring block and the second neighboring block is formed in a rectangular shape by asymmetric partition.

13. The decoding device of claim 10, wherein a prediction motion vector generator is configured to interpolate the motion vector of the first neighboring block of the current block based on the first distance and the second distance to generate the first interpolated motion vector, when the first distance is equal to or greater than the second distance.

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

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

17. The decoding device of claim 10, wherein the prediction motion vector generator is configured to select one among a plurality of interpolated motion vectors including the first interpolated motion vector and the second interpolated motion vector as the predicted motion vector.

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

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

interpolating, by the encoding device, a motion vector of a first neighboring block of the current block based on a first distance and a second distance to generate a first interpolated motion vector, wherein the first neighboring block and the current block are in a current picture, the first distance is a distance between a reference picture of the first neighboring block and the current picture, the second distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the first neighboring block is used to encode the first neighboring block according to the reference picture of the first neighboring block, wherein the reference picture of the first neighboring block is different from the reference picture of the current block;

interpolating, by the encoding device, a motion vector of a second neighboring block of the current block based on a third distance and a fourth distance to generate a second interpolated motion vector, wherein the second neighboring block is in the current picture, the third distance is a distance between a reference picture of the second neighboring block and the current picture, the fourth distance is a distance between a reference picture of the current block and the current picture, and the motion vector of the second neighboring block is used to encode the second neighboring block according to the reference picture of the second neighboring block, wherein the reference picture of the second 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 first interpolated motion vector and the second interpolated motion vector to generate a predicted motion vector of the current block;

generating, by the encoding device, the 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 of the current block.

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