Method and apparatus for encoding multiview video

1 . A method of encoding a multiview video, the method comprising:

categorizing a plurality of B frames into at least two groups according to a predetermined standard; and

sequentially encoding the categorized plurality of B frames.

2 . The method of claim 1 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers.

3 . The method of claim 1 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers and view positions of the frames.

4 . The method of claim 1 ,

wherein the plurality of B frames are categorized into a first group of B frames which are predicted with reference to two horizontally adjacent frames, two vertically adjacent frames or one horizontally adjacent frame and one vertically adjacent frame, a second group of B frames which are predicted with reference to two horizontally adjacent frames and one vertically adjacent frame or one horizontally adjacent frame and two vertically adjacent frames, and a third group of B frames which are predicted with reference to two horizontally adjacent frames and two vertically adjacent frames, and

wherein the one or two horizontally adjacent frames are a frame or frames obtained from the multiview video at a same temporal level as a B frame of the first group, the second group or the third group, and the one or two vertically adjacent frames are a frame or frames obtained from the multiview video at a same view position as the B frame of the first group, the second group or the third group.

5 . The method of claim 4 , wherein the sequential encoding of the categorized plurality of B frames comprises sequentially encoding the first group of B frames, the second group of B frames, and the third group of B frames.

6 . The method of claim 1 ,

wherein the sequential encoding is performed based on a video encoding structure comprising the plurality of B frames,

wherein the sequential encoding comprises performing disparity estimation between frames disposed horizontally according to a plurality of views and performing motion estimation between frames disposed vertically according to passage of time,

wherein the video encoding structure is extendible at least one of horizontal and vertical directions, and

wherein the frames disposed horizontally are frames obtained from the multiview video at a same temporal level, and the frames disposed vertically are frames obtained from the multiview video at a same view position.

7 . The method of claim 6 , wherein the plurality of views comprises n views, where n is an odd natural number.

8 . The method of claim 7 , wherein frames obtained at an (n-1)th view are not used for the disparity estimation and the motion estimation.

9 . The method of claim 7 , wherein, in the video encoding structure, frames obtained at views except a first view, among the plurality of views, do not include an I frame, and frames obtained at a k-th view comprises only B frames, where k is an even natural number which is smaller than n.

10 . An apparatus for encoding a multiview video, the apparatus comprising:

a prediction unit which predicts a disparity vector and a motion vector of an input multiview video;

a disparity and motion compensation unit which compensates an image using the disparity vector and the motion vector;

a residual image encoding unit which receives the input multiview video and the compensated image generated by the disparity and motion compensation unit, subtracts the compensated image from the original image, and encodes a residual image obtained from the subtraction; and

an entropy-encoding unit which generates a bit stream for the multiview video using the disparity vector, the motion vector, and the encoded residual image,

wherein the prediction unit categorizes a plurality of B frames into at least two groups according to a predetermined standard and sequentially predicts the categorized plurality of B frames.

11 . The apparatus of claim 10 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers.

12 . The apparatus of claim 10 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers and view positions of the frames.

13 . The apparatus of claim 10 , wherein the plurality of B frames are categorized into a first group of B frames which are predicted with reference to two horizontally adjacent frames, two vertically adjacent frames or one horizontally adjacent frame and one vertically adjacent frame, a second group of B frames which are predicted with reference to two horizontally adjacent frames and one vertically adjacent frame or one horizontally adjacent frame and two vertically adjacent frames, and a third group of B frames which are predicted with reference to two horizontally adjacent frames and two vertically adjacent frames,

wherein the one or two horizontally adjacent frames are a frame or frames obtained from the multiview video at a same temporal level as a B frame of the first group, the second group or the third group, and the one or two vertically adjacent frames are a frame or frames obtained from the multiview video at a same view position as the B frame of the first group, the second group or the third group.

14 . The apparatus of claim 13 , wherein the prediction unit sequentially predicts the first group of B frames, the second group of B frames, and the third group of B frames.

15 . The apparatus of claim 10 ,

wherein the prediction unit predicts the disparity vector and the motion vector of an input multiview video based on a video encoding structure comprising the plurality of B frames,

wherein the prediction unit further performs disparity estimation between frames disposed horizontally according to a plurality of views and performs motion estimation between frames disposed vertically according to passage of time,

wherein the video encoding structure is extendible at least one of horizontal and vertical directions, and

wherein the frames disposed horizontally are frames obtained from the multiview video at a same temporal level, and the frames disposed vertically are frames obtained from the multiview video at a same view position.

16 . The apparatus of claim 15 , wherein the plurality of views comprises n views, where n is an odd natural number.

17 . The apparatus of claim 16 , wherein frames obtained at an (n-1)th view are not used for the disparity estimation and the motion estimation.

18 . The apparatus of claim 16 , wherein, in the video encoding structure, frames obtained at views except a first view, among the plurality of views, do not include an I frame, and frames obtained at a k-th view comprises only B frames, where k is an even natural number which is smaller than n.

19 . A computer-readable recording medium storing a method of encoding a multiview video, the method comprising:

categorizing a plurality of B frames into at least two groups according to a predetermined standard; and

sequentially encoding the categorized plurality of B frames.

20 . The computer-readable recording medium of claim 19 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers.

21 . The computer-readable recording medium of claim 19 , wherein the predetermined standard comprises a number of frames to which each of the plurality of B frames refers and view positions of the frames.

22 . The computer-readable recording medium of claim 19 ,

wherein the plurality of B frames are categorized into a first group of B frames which are predicted with reference to two horizontally adjacent frames, two vertically adjacent frames or one horizontally adjacent frame and one vertically adjacent frame, a second group of B frames which are predicted with reference to two horizontally adjacent frames and one vertically adjacent frame or one horizontally adjacent frame and two vertically adjacent frames, and a third group of B frames which are predicted with reference to two horizontally adjacent frames and two vertically adjacent frames, and

wherein the one or two horizontally adjacent frames are a frame or frames obtained from the multiview video at a same temporal level as a B frame of the first group, the second group or the third group, and the one or two vertically adjacent frames are a frame or frames obtained from the multiview video at a same view position as the B frame of the first group, the second group or the third group.

23 . The computer-readable recording medium of claim 22 , wherein the sequential encoding of the categorized plurality of B frames comprises sequentially encoding the first group of B frames, the second group of B frames, and the third group of B frames.

24 . The computer-readable recording medium of claim 19 , wherein the sequential encoding is performed based on a video encoding structure comprising the plurality of B frames,

wherein the sequential encoding comprises performing disparity estimation between frames disposed horizontally according to a plurality of views and performing motion estimation between frames disposed vertically according to passage of time,

wherein the video encoding structure is extendible at least one of horizontal and vertical directions, and

wherein the frames disposed horizontally are frames obtained from the multiview video at a same temporal level, and the frames disposed vertically are frames obtained from the multiview video at a same view position.

25 . The computer-readable recording medium of claim 24 , wherein the plurality of views comprises n views, where n is an odd natural number.

26 . The computer-readable recording medium of claim 25 , wherein frames obtained at an (n-1)th view are not used for the disparity estimation and the motion estimation.

27 . The computer-readable recording medium of claim 25 , wherein, in the video encoding structure, frames obtained at views except a first view, among the plurality of views, do not include an I frame, and frames obtained at a k-th view comprises only B frames, where k is an even natural number which is smaller than n.