Motion vector encoding device and decoding device

• US 20030128762A1
• Filed: 02/28/2003
• Published: 07/10/2003
• Est. Priority Date: 10/29/1998
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nakagawa, Akira, Itoh, Takashi, Morimatsu, Eishi, Anan, Taizo
• Granted Patent: US 7,310,372 B2
• Time in Patent Office: Days
• US Class Current: 375/240.16
• 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 19/12 Selection from among a plurality of transforms or standards, e.g. selection between discrete cosine transform [DCT] and sub-band transform or selection between H.263 and H.264
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/137 Motion inside a coding unit, e.g. average field, frame or block difference
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/513 Processing of motion vectors
• CPC Class Codes: H04N 19/52 by predictive encoding
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

A prediction error generating unit generates a predictive vector from the motion vectors of a plurality of adjacent blocks, and obtains a difference from a target vector. A plurality of variable-length coding units respectively encode the output of the prediction error generating unit with different encoding methods. A determining unit estimates the accuracy of the predictive vector generated by the prediction error generating unit based on the degrees of non-uniformity of the motion vectors of the plurality of adjacent blocks. A selecting unit selects one of the encoding results obtained by the plurality of variable-length coding units.

Claims

1. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

predicting means for predicting a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

determining means for determining accuracy of a prediction made by said predicting means based on degrees of non-uniformity of the plurality of motion vectors; and

encoding means for encoding the motion vector of the target block using a result of the prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

2. The motion vector encoding device according to claim 1, wherein said determining means determines the accuracy of the prediction made by said predicting means based on the degrees of non-uniformity of the plurality of motion vectors which have already been encoded in an area adjacent to the target block.

3. The motion vector encoding device according to claim 1, wherein said encoding means comprises:

a plurality of individual encoding means for encoding the motion vector of the target block with unique encoding methods; and

selecting means for selecting one of said plurality of individual encoding means based on the result of the determination made by said determining means, and for outputting a result of encoding performed by the selected individual encoding means;

4. The motion vector encoding device according to claim 3, wherein said plurality of individual encoding means respectively encode the motion vector of the target block by using different variable-length codes.

5. The motion vector encoding device according to claim 1, wherein:

said predicting means comprises first and second predicting means for respectively predicting first and second components of the motion vector of the target block;

,

said determining means comprises

first determining means for determining the accuracy of the prediction made by said first predicting means based on degrees of non-uniformity of respective first components of the plurality of motion vectors, and

second determining means for determining the accuracy of the prediction made by said second predicting means based on degrees of non-uniformity of respective second components of the plurality of motion vectors, a first component of the motion vector of the target block, and the respective first components of the plurality of motion vectors; and

said encoding means comprises

first encoding means for encoding the first component of the motion vector of the target block by using a result of a prediction made by said first predicting means with an encoding method determined based on a result of a determination made by said first determining means, and

second encoding means for encoding the second component of the motion vector of the target block by using a result of a prediction made by said second predicting means with an encoding method determined based on a result of a determination made by said second determining means.

6. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

predicting means for predicting a motion vector of a target block based on motion vectors of a plurality of other blocks within a frame to which the target block belongs;

determining means for determining accuracy of a prediction made by said predicting means based on degrees of non-uniformity of the plurality of motion vectors which have already been encoded within the frame to which the target block belongs; and

encoding means for encoding the motion vector of the target block by using a result of the prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

7. A motion vector encoding device, which is arranged within an interframe predictive coding device for encoding moving image data by using a plurality of motion vectors, for encoding a motion vector, comprising:

predicting means for predicting a target motion vector based on a plurality of motion vectors adjacent to the target motion vector;

determining means for determining accuracy of a prediction made by said predicting means based on degrees of non-uniformity of the plurality of motion vectors; and

encoding means for encoding the target motion vector by using a result of a prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

8. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

recognizing means for recognizing a nature of an image in an area adjacent to a target block; and

encoding means for encoding a motion vector of the target block with an encoding method determined based on a result of recognition made by said recognizing means.

9. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

a predictor which predicts a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

a detector which detects accuracy of a prediction made by said predictor based on degrees of non-uniformity of the plurality of motion vectors; and

an encoder which encodes the motion vector of the target block using a result of the prediction made by said predictor with an encoding method determined based on a detected result by said detector.

10. A motion vector encoding method for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising the steps of:

predicting a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

determining accuracy of the prediction based on degrees of non-uniformity of the plurality of motion vectors; and

encoding the motion vector of the target block by using a result of the prediction with an encoding method determined based on a result of a determination of the accuracy of the prediction.

11. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

predicting means for predicting a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

determining means for determining accuracy of a prediction made by said predicting means based on the plurality of motion vectors; and

encoding means for encoding the motion vector of the target block using a result of the prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

12. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

predicting means for predicting a motion vector of a target block based on motion vectors of a plurality of other blocks within a frame to which the target block belongs;

determining means for determining accuracy of a prediction made by said predicting means based on the plurality of motion vectors which have already been encoded within the frame to which the target block belongs; and

encoding means for encoding the motion vector of the target block by using a result of the prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

13. A motion vector encoding device, which is arranged within an interframe predictive coding device for encoding moving image data by using a plurality of motion vectors, for encoding a motion vector, comprising:

predicting means for predicting a target motion vector based on a plurality of motion vectors adjacent to the target motion vector;

determining means for determining accuracy of a prediction made by said predicting means based on the plurality of motion vectors; and

encoding means for encoding the target motion vector by using a result of a prediction made by said predicting means with an encoding method determined based on a result of a determination made by said determining means.

14. A motion vector encoding device for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising:

a predictor which predicts a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

a detector which detects accuracy of a prediction made by said predictor based on the plurality of motion vectors; and

an encoder which encodes the motion vector of the target block using a result of the prediction made by said predictor with an encoding method determined based on a detected result by said detector.

15. A motion vector encoding method for encoding motion vectors of respective blocks obtained by partitioning each frame of moving image data, comprising the steps of:

predicting a motion vector of a target block based on motion vectors of a plurality of blocks adjacent to the target block;

determining accuracy of the prediction based on the plurality of motion vectors; and

encoding the motion vector of the target block by using a result of the prediction with an encoding method determined based on a result of a determination of the accuracy of the prediction.