U.S. patent application number 11/992942 was filed with the patent office on 2009-05-21 for method for decoding and encoding a video signal.
Invention is credited to Byeong Moon Jeon, Dong Seok Kim, Ji Ho Park, Seung Wook Park.
Application Number | 20090129468 11/992942 |
Document ID | / |
Family ID | 38159776 |
Filed Date | 2009-05-21 |
United States Patent
Application |
20090129468 |
Kind Code |
A1 |
Park; Seung Wook ; et
al. |
May 21, 2009 |
Method for Decoding and Encoding a Video Signal
Abstract
A method for decoding/encoding a video signal using an inter
layer prediction process is disclosed. The method for decoding a
video signal including several layer information includes: a)
acquiring a first prediction signal for a current block of an
enhancement layer and a residual signal based on at least a base
layer block; b) smoothing the sum of the first prediction signal
and the residual signal, and generating a second prediction signal
for the current block; and c) reconstructing the current block
based on the second prediction signal. Therefore, the method for
decoding/encoding a video signal uses a variety of inter layer
prediction methods according to the macroblock type of macroblocks
of the current and base layers, and removes inter layer redundancy,
resulting in increased coding efficiency.
Inventors: |
Park; Seung Wook; (Seoul,
KR) ; Jeon; Byeong Moon; (Seoul, KR) ; Kim;
Dong Seok; (Seoul, KR) ; Park; Ji Ho; (Seoul,
KR) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 8910
RESTON
VA
20195
US
|
Family ID: |
38159776 |
Appl. No.: |
11/992942 |
Filed: |
October 9, 2006 |
PCT Filed: |
October 9, 2006 |
PCT NO: |
PCT/KR2006/004029 |
371 Date: |
April 1, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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60723474 |
Oct 5, 2005 |
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60729220 |
Oct 24, 2005 |
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Current U.S.
Class: |
375/240.13 ;
375/240.12; 375/E7.026; 375/E7.027; 375/E7.09 |
Current CPC
Class: |
H04N 19/159 20141101;
H04N 19/33 20141101; H04N 19/103 20141101; H04N 19/105 20141101;
H04N 19/61 20141101; H04N 19/82 20141101; H04N 19/187 20141101;
H04N 19/176 20141101 |
Class at
Publication: |
375/240.13 ;
375/240.12; 375/E07.026; 375/E07.027; 375/E07.09 |
International
Class: |
H04N 7/26 20060101
H04N007/26; H04N 11/02 20060101 H04N011/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 2, 2006 |
KR |
10-2006-0097359 |
Claims
1. A method for decoding a video signal including several layer
information comprising: a) acquiring a first prediction signal for
a current block of an enhancement layer and a residual signal based
on at least a base layer block; b) smoothing the sum of the first
prediction signal and the residual signal, and generating a second
prediction signal for the current block; and c) reconstructing the
current block based on the second prediction signal.
2. The method according to claim 1, wherein the reconstructing step
c) of the current block includes: adding the second prediction
signal for the current block and a residual signal; and
reconstructing the current block.
3. The method according to claim 1, wherein the generating step a)
of the first prediction signal includes: generating the first
prediction signal on the basis of at least one prediction mode
information from among the current block and a block of the base
layer.
4. The method according to claim 3, wherein the prediction mode
information of the current block is indicative of an intra
prediction mode.
5. The method according to claim 4, wherein the prediction mode
information of the base layer block is indicative of an inter
prediction mode.
6. The method according to claim 3, wherein the prediction mode
information of the base layer block is indicative of an inter
prediction mode.
7. The method according to claim 2, wherein the residual signal is
based on the enhancement layer.
8. The method according to claim 1, wherein the residual signal
includes an umsmapled video signal based on the base layer
block.
9. The method according to claim 8, wherein the upsampling
increases resolution of the base layer according to resolution of
the enhancement layer.
Description
TECHNICAL FIELD
[0001] The present invention relates to a method for
decoding/encoding a video signal, and more particularly to a method
for decoding/encoding a video signal using an inter layer
prediction process.
BACKGROUND ART
[0002] Generally, a Moving Picture Experts Group (MPEG) under
ISO/IEC (International Organization for
Standardization/International Electro-technical Commission) and a
Video Coding Experts Group (VCEG) under ITU-T (International
Telecommunications Union Telecommunication Standardization sector)
have jointly configured a Joint Video Team (JVT), such that they
have proposed a new standard capable of implementing a video image
compression performance superior to those of the MPEG-4 Part 2
standard and the H.263 standard. Representative examples of the
above-mentioned new standard are an MPEG-4 AVC (MPEG-4 Part 10:
Advanced Video Coding) proposed by the ISO/IEC and the H.264
standard proposed by the ITU-T.
[0003] There must be developed a new method for encoding moving
pictures or moving images, such that it must maximize compression
efficiency, and must suitably cope with a variety of terminals and
variable communication environments. With the above-mentioned
demands of the aforementioned enhanced encoding method, the JVT
acting as a collaboration team of the ISO/TEC and the ITU-T is
conducting intensive research into the standardization of Scalable
Video Coding (SVC) based on H.264/AVC.
[0004] The scalable video coding (SVC) basically includes three
scalability methods, i.e., temporal scalability, spatial
scalability, and SNR scalability.
[0005] The spatial scalability has been executed by an inter layer
prediction process, and the SVC provides the increase of coding
efficiency.
[0006] The above-mentioned inter layer prediction calculates a high
correlation between several layers, such that the overlapping
information can be removed from the resultant images by an inter
layer prediction process. Therefore, a variety of prediction
methods capable of performing the inter-layer prediction must be
newly developed.
DISCLOSURE OF INVENTION
Technical Problem
[0007] An object of the present invention is to provide various
method for decoding and encoding a video signal by inter layer
prediction.
Technical Solution
[0008] Reference will now be made in detail to the preferred
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings.
[0009] The above-mentioned inter layer prediction is classified
into a texture prediction and a motion prediction.
[0010] The texture prediction is classified into an intra base
prediction and a residua prediction. The motion prediction is
classified into a base mode, a base mode refinement, and a motion
prediction mode.
[0011] The above-mentioned intra base prediction will be described
in detail. If a lower layer macroblock corresponding to a target
macroblock to be encoded is encoded by an intra prediction mode,
the above-mentioned intra base prediction reconstructs the lower
layer macroblock, performs upsampling of the reconstructed
macroblock at resolution of the target macroblock to be encoded,
and uses the upsampling result as a prediction signal.
[0012] The above-mentioned residual prediction will be described in
detail. If a lower layer macroblock corresponding to a target
macroblock to be encoded is encoded by an inter prediction mode,
such that the lower layer macroblock includes a residual signal,
the above-mentioned residual prediction performs the inter layer
prediction on the residual signal. Therefore, if motion information
of a current macroblock is equal to or similar to that of the lower
layer macroblock, the residual prediction performs upsampling of
the encoded lower layer residual signal, and uses the upsampling
result as a prediction signal of a current macroblock, such that it
can remove the inter-layer overlapping information. The
above-mentioned base mode will be described in detail. If a lower
layer is present between at least two layers having different
resolution, the base mode performs upsampling of motion information
acquired form the lower layer without using a motion estimation
within a current layer, and uses the upsampling resultant
image.
[0013] A method for decoding/encoding a video signal using an inter
layer prediction process according to the present invention will
hereinafter be described with reference to the annexed
drawings.
[0014] FIG. 1 is a flow chart illustrating a method for decoding a
video signal according to the present invention.
[0015] Referring to FIG. 1, the video signal decoding method
acquires a first prediction signal for a current block of an
enhancement layer and a residual signal based on at least a base
layer block at step S10. In other words, the video signal decoding
method according to the present invention uses the inter layer
prediction, such that it should be noted that the video signal
decoding method uses a first prediction signal for a current layer
as a predictor signal capable of decoding a current macroblock and
a residual signal based on a base layer block.
[0016] In this case, the first prediction signal for the current
block can be generated by at least one prediction mode information
from among the current block and the base layer block.
[0017] For example, the macroblock type of the current block is an
inter macroblock, the prediction signal is generated by a motion
vector of the current macroblock. If the macroblock type of the
current block is an intra macroblock, the prediction signal is
generated by an intra prediction mode of the current
macroblock.
[0018] In this case, the intra prediction mode is indicative of one
of prediction directions acquired when the prediction mode is
performed by referring to neighboring macroblocks during the intra
prediction encoding mode.
[0019] For example, the 4.times.4 pixel-unit intra prediction
includes 9 modes according to 9 prediction directions. The higher
the generation frequency of a corresponding prediction direction,
the lower the allocation number of the corresponding prediction
direction.
[0020] The residual signal based on the base layer block is
indicative of a residual signal generated according to the
macroblock type of macroblocks contained in the base layer.
[0021] In the meantime, a method for generating a second prediction
signal as a representative example of the video signal decoding
method according to the present invention will hereinafter be
described with reference to FIGS. 2-7.
[0022] The video signal decoding method performs smoothing of the
sum of the first prediction signal and the residual signal
generated at step S10, and generates a second prediction signal for
a current block at step S12.
[0023] The video signal decoding method reconstructs the current
block by adding the second prediction signal and the residual
signal at step S14. In other words, the video signal decoding
method receives the residual signal for a current layer from an
encoding unit, and adds the second prediction signal acting as a
predictor and the residual signal, such that it reconstructs a
current macroblock.
[0024] Also, the video signal decoding method performs
smoothing-filtering of the second prediction signal, and adds the
smoothing-filtered second prediction signal and the residual signal
for the current layer, such that it can decode a current
macroblock.
[0025] In this case, the term smoothing-filtering is indicative of
a specific process for smoothing directivity of a prediction signal
generated by the intra prediction mode.
[0026] FIG. 2 is a conceptual diagram illustrating the video signal
decoding method of FIG. 1 according to the present invention.
[0027] Provided that the macroblock type of macroblocks contained
in current and base layers are indicative of intra macroblocks, a
method for generating a second prediction signal according to a
first preferred embodiment of the present invention is depicted in
FIG. 2.
[0028] Referring to FIG. 2, a first prediction signal 201 (Pc) is
generated by an intra prediction mode of a macroblock of a current
layer. In other words, the video signal decoding method of FIG. 2
performs an intra prediction encoding process in a pre-determined
direction under the intra prediction mode, such that it acquires a
prediction signal.
[0029] For example, if the intra prediction mode of the current
layer macroblock indicates "2" the 4.times.4 pixel-unit intra
prediction encoding process calculates an average value of eight
pixels (i.e., four pixels of the left block and four pixels of the
upper block), and generates a first prediction signal. The residual
signal 203 (Rb) for the base layer is generated by the intra
prediction mode of the macroblock of the base layer.
[0030] In other words, the video signal decoding method of FIG. 2
calculates a difference between the prediction signal generated by
the intra prediction mode of the base layer macroblock and the base
layer macroblock, and generates a residual signal 203 (Rb) for the
base layer.
[0031] Finally, the second prediction signal 207 is generated by
the sum of the upsampling signal 205 (u) and the first prediction
signal 201 (Pc). The upsampling signal 205 (u) is generated by
upsampling the residual signal 203 (Rb) for the base layer at
resolution of the current layer.
[0032] In this case, according to the video signal decoding method
according to the present invention, the current macroblock 213 (0c)
adds the smoothing-filtering signal 209 of the second prediction
signal 207 and the residual signal 211 (Rc) for the current layer,
resulting in the implementation of the reconstruction of the
current macroblock 213 (0c), as represented by an equation
"Oc=Rc+f(Pc+u(Rb))".
[0033] FIG. 3 is a conceptual diagram illustrating a video signal
decoding method of FIG. 1 according to the present invention.
[0034] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of intra macroblocks, a
method for generating a second prediction signal according to the
present invention is depicted in FIG. 3.
[0035] Referring to FIG. 3, a first prediction signal 301 (Pc) is
generated by an intra prediction mode of a macroblock of a base
layer, differently from the first prediction signal 201 of FIG. 2.
The residual signal 303 (Rb) for the base layer and the second
prediction signal 307 are generated by the same method as the video
signal decoding method of FIG. 2.
[0036] In this case, the video signal decoding method according to
the present invention reconstructs the current macroblock 313 (0c)
by adding the smoothing-filtering signal 309 (f) of the second
prediction signal 307 and the residual signal 311 (Rc) for the
current layer, as represented by an equation
"Oc=Rc+f(Pc+u(Rb))"
[0037] In this case, in order to perform the video signal decoding
method of FIG. 3, the video signal decoding method according to the
present invention may use a new syntax, or may also use residual
prediction flag information (residual_prediction_flag) or base mode
flag information (base_mode_flag), etc.
[0038] FIG. 4 is a conceptual diagram illustrating a video signal
decoding method of FIG. 1 according to the present invention.
[0039] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of intra macroblock and
inter macroblock, a method for generating a second prediction
signal according to the present invention is depicted in FIG.
4.
[0040] Referring to FIG. 4, a residual signal 403 (Rb) for the base
layer is generated by the inter prediction mode. In other words,
the video signal decoding method of FIG. 4 calculates a difference
between the prediction signal generated by the motion vector of the
base layer macroblock and the base layer macroblock, thereby
generating a residual signal 403 (Rb) for the base layer.
[0041] The first prediction signal 401 (Pc) and the second
prediction signal 407 are generated by the same method as the video
signal decoding method of FIG. 2.
[0042] In this case, the video signal decoding method according to
the present invention reconstructs the current macroblock 413 (0c)
by adding the smoothing-filtering signal 409 (f) of the second
prediction signal 407 and the residual signal 411 (Rc) for the
current layer, as represented by an equation
"Oc=Rc+f(Pc+u(Rb))"
[0043] FIG. 5 is a conceptual diagram illustrating a video signal
decoding method of FIG. 1 according to the present invention.
[0044] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of intra macroblock and
inter macroblock, a method for generating a second prediction
signal according to the present invention is depicted in FIG.
5.
[0045] Referring to FIG. 5, a first prediction signal 501 (Pc) and
a residual signal 503 (Rb) for the base layer are generated by the
video signal decoding method of FIG. 5. Finally, a second
prediction signal 509 is generated by upsampling the sum 507 of the
downsampling signal 505 of the first prediction signal 501 (Pc) and
the residual signal 503 (Rb) for the base layer at resolution of
the current layer.
[0046] In this case, the video signal decoding method according to
the present invention reconstructs the current macroblock 515 (0c)
by adding the smoothing-filtering signal 513 (f) of the second
prediction signal 509 and the residual signal 511 (Rc) for the
current layer, as represented by an equation
"Oc=Rc+f(u(d(Pc)+Rb))"
[0047] FIG. 6 is a conceptual diagram illustrating a video signal
decoding method of FIG. 1 according to the present invention.
[0048] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of inter macroblock and
intra macroblock, a method for generating a second prediction
signal according to the present invention is depicted in FIG.
6.
[0049] Referring to FIG. 6, a first prediction signal 601 (Pc) is
generated by a motion vector of a current layer macroblock. In
other words, the first prediction signal 601 (Pc) is generated by
the inter prediction.
[0050] The residual signal 603 (Rb) for the base layer is generated
by the intra prediction mode of the base layer macroblock. Finally,
the second prediction signal 607 is generated by the sum of the
upsampling signal 605 (u) and the first prediction signal 601 (Pc).
In this case, the upsampling signal 605 is generated by upsampling
the residual signal 603 (Rb) for the base layer at resolution of
the current layer.
[0051] In this case, the video signal decoding method according to
the present invention reconstructs the current macroblock 613 (0c)
by adding the smoothing-filtering signal 609 (f) of the second
prediction signal 607 and the residual signal 611 (Rc) for the
current layer, as represented by an equation
"Oc=Rc+f(Pc+u(Rb))".
[0052] FIG. 7 is a conceptual diagram illustrating a video signal
decoding method of FIG. 1 according to the present invention.
[0053] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of inter macroblock and
intra macroblock, a method for generating a second prediction
signal according to the present invention is depicted in FIG.
7.
[0054] Referring to FIG. 7, a first prediction signal 701 (Pc) and
a residual signal 703 (Rb) for the base layer are generated by the
video signal decoding method of FIG. 6. Finally, the second
prediction signal 709 is generated by the same method as the video
signal decoding method of FIG. 7.
[0055] In this case, the video signal decoding method according to
the present invention reconstructs the current macroblock 715 (0c)
by adding the smoothing-filtering signal 713 (f) of the second
prediction signal 709 and the residual signal 711 (Rc) for the
current layer, as represented by an equation
"Oc=Rc+f(u(d(Pc)+Rb))"
[0056] FIG. 8 is a flow chart illustrating a method for encoding a
video signal according to the present invention.
[0057] Referring to FIG. 8, the video signal encoding method
according to the present invention generates a second prediction
signal for the current layer using a first prediction signal and a
residual signal for a base layer at step S80. In other words, the
video signal encoding method according to the present invention
uses an inter layer prediction method, such that it can be
recognized that the first prediction signal for the current layer
and the residual signal for the base layer are used as predictor
signals for encoding the current macroblock.
[0058] In this case, the first prediction signal for the current
layer is indicative of a prediction signal generated by the
macroblock type of the current layer macroblock. If the macroblock
type is indicative of the inter macroblock, the video signal
encoding method according to the present invention generates the
prediction signal using a motion vector of the current macroblock.
Otherwise, if the macroblock type is indicative of the intra
macroblock, the video signal encoding method according to the
present invention generates the prediction signal by an intra
prediction mode of the current macroblock.
[0059] Also, the residual signal for the base layer is indicative
of a residual signal generated by the macroblock types of
macroblocks contained in the base layer.
[0060] A method for generating a second prediction signal according
to a preferred embodiment of the video signal encoding method will
hereinafter be described with reference to FIGS. 9.about.10.
[0061] Referring to FIG. 9.about.10, the video signal encoding
method according to the present invention encodes the residual
signal between the second prediction signal generated at step S80
and the current macroblock at step S82. In other words, the video
signal encoding method encodes the residual signal between the
second prediction signal acting as the prediction signal and the
current macroblock, and transmits the resultant signal to a
decoding unit.
[0062] The video signal encoding method according to the present
invention performs smoothing-filtering of the second prediction
signal, and can encode the residual signal between the
smoothing-filtered second prediction signal and the current
macroblock. In this case, the term smoothing-filtering is
indicative of a specific process for smoothing directivity of a
prediction signal generated by the intra prediction mode.
[0063] FIG. 9 is a conceptual diagram illustrating the video signal
encoding method of FIG. 8 according to the present invention.
[0064] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of intra macroblocks, a
method for generating a second prediction signal according to the
present invention is depicted in FIG. 9.
[0065] Referring to FIG. 9, a first prediction signal 901 (Pc) is
generated by the intra prediction mode of the current layer
macroblock 907. In other words, the video signal encoding method of
FIG. 9 acquires the prediction signal by performing an intra
prediction encoding process in a predetermined direction under the
intra prediction mode.
[0066] The residual signal 903 (Rb) for the base layer is generated
by the intra prediction mode of the base layer macroblock. In other
words, the video signal encoding method of FIG. 9 calculates a
difference between the prediction signal generated by the intra
prediction mode of the base layer macroblock and the base layer
macroblock, thereby generating the residual signal 903 (Rb) for the
base layer. Finally, the second prediction signal 905 is generated
by the sum of the upsampling signal (u) of the residual signal 903
(Rb) for the base layer and the first prediction signal 901 (Pc).
In this case, the upsampling signal (u) is generated by upsampling
the residual signal 903 at resolution of the current layer.
[0067] In this case, the video signal encoding method according to
the present invention generates the residual signal 909 (Rc) by
calculating a difference between the smoothing-filtering signal (f)
of the second prediction signal 905 and the current macroblock, and
is then encoded, as represented by an equation
"Rc=Oc-f(Pc+u(Rb))"
[0068] The prediction signal 905 is required for allowing the
encoding unit to generate the residual signal 909. The video signal
encoding method according to the present invention generates the
prediction signal 905 by adding the intra prediction mode signal
901 of the current layer macroblock and the upsampling signal of
the base layer residual signal 903, such that it can generate more
accurate prediction signal, resulting in the increase of encoding
efficiency. In this case, the upsampling signal is generated by
upsampling the residual signal 903 for the base layer at resolution
of the current layer.
[0069] FIG. 10 is a conceptual diagram illustrating a video signal
encoding method of FIG. 8 according to the present invention.
[0070] Provided that the macroblock types of macroblocks contained
in current and base layers are indicative of intra macroblocks, a
method for generating a second prediction signal according to the
present invention is depicted in FIG. 10.
[0071] Referring to FIG. 10, a first prediction signal 101 (Pc) and
the residual signal 103 (Rb) for the base layer are generated by
the intra prediction mode of the base layer macroblock. In other
words, the video signal encoding method of FIG. 10 calculates a
difference between the prediction signal generated by the intra
prediction mode of the base layer macroblock and the base layer
macroblock, such that it generates a residual signal 103 (Rb) for
the base layer. According to the present invention, the first
prediction signal 101 is generated by the intra prediction mode of
the base layer macroblock, such that a correlation between the base
layer macroblock and the current layer macroblock is high.
Therefore, the video signal encoding method according to the
present invention can generate more accurate predictor signal,
resulting in the increase of coding efficiency.
[0072] Finally, the second prediction signal 105 is generated by
adding the upsampling signal (u) and the first prediction signal
101 (Pc). The upsampling signal (u) is generated by upsampling the
residual signal 103 (Rb) for the base layer at resolution of the
current layer.
[0073] In this case, the video signal encoding method according to
the present invention generates the residual signal 109 (Rc) by
calculating a difference between the smoothing-filtering signal (f)
of the second prediction signal 105 and the current macroblock, and
is then encoded, as represented by an equation
"Rc=Oc-f(Pc+u(Rb))"
[0074] Flag information of the video signal decoding method of FIG.
10 can be encoded. In this case, a new syntax may be used as the
flag information. Otherwise, residual prediction flag information
(residual_prediction_flag) or base mode flag information
(base_mode_flag) can be used as the flag information.
[0075] A method for generating a first prediction signal, a
residual signal for a base layer, and the second prediction signal
using the video signal encoding method (not shown) corresponding to
the video signal decoding method of FIGS. 4.about.7 are equal to
those of FIGS. 4.about.7.
[0076] A weight prediction method (not shown) for an intra base
prediction from among inter layer prediction methods will
hereinafter be described in detail.
[0077] A video signal encoding method based on the intra base
prediction is as follows.
[0078] A weight (w) is multiplied to the upsampling signal (B) of a
current layer corresponding to the base layer macroblock, and an
offset value (o) is added to the multiplied result, such that a
prediction signal for the current layer is generated. In this case,
the weight may be the weight of a chromatic signal (chroma) or a
luminescence signal (luma), and the offset value may be the offset
value of the chromatic signal (chroma) or the luminescence signal
(luma).
[0079] Finally, the video signal encoding method based on the intra
base prediction encodes the residual signal (R) between the current
layer prediction and the current layer macroblock (S), as
represented by an equation "R=S-(B*w+o)". Also, the video signal
encoding method based on the intra base prediction can encode the
flag information indicating the above-mentioned prediction method,
and can also encode weight and offset value information.
[0080] In this case, a new syntax i.e., a weighted intra base
prediction flag (weighted_intra_base_prediction_flag) may be
defined as the flag information indicating the prediction
method.
[0081] For example, if the weighted intra base prediction flag
(weighted_intra_base_prediction_flag) is indicative of "1" this
indicates that the weight and offset values of the luminescence
signal and the chromatic signal are applied to the intra base
prediction. If the weighted intra base prediction flag
(weighted_intra_base_prediction_flag) is indicative of "0" this
indicates that the weight and offset values of the luminescence
signal and the chromatic signal are not applied to the intra base
prediction.
[0082] Also, the weight information of the luminescence signal and
the chromatic signal may be a weight itself, and the offset value
information of the luminescence signal and the chromatic signal may
be an offset value itself. Otherwise, the weight information and
the offset value information may also be indicative of specific
information capable of acquiring weight and offset values.
[0083] A video signal decoding method based on intra base
prediction is as follows.
[0084] The above-mentioned video signal decoding method based on
intra base prediction calculates the weight (w) and the offset
value (o) using the weight and offset value information according
to the weighted intra base prediction flag
(weighted_intra_base_prediction_flag).
[0085] For example, if the weighted intra base prediction flag
(weighted_intra_base_prediction_flag) is indicative of "1" this
indicates that the weight and offset values of the luminescence
signal and the chromatic signal are applied to the intra base
prediction. If the weighted intra base prediction flag
(weighted_intra_base_prediction_flag) is indicative of "0" this
indicates that the weight and offset values of the luminescence
signal and the chromatic signal are not applied to the intra base
prediction.
[0086] The above-mentioned video signal decoding method based on
intra base prediction generates a prediction signal for a current
layer using the calculated weight (w) and the offset value (o).
[0087] Finally, the above-mentioned video signal decoding method
based on intra base prediction adds the prediction signal for the
current layer and the residual signal (R), and decodes the
macroblock (S) of the current layer, as represented by an equation
"S=R+(B*w+o)"
[0088] Therefore, the above-mentioned method for decoding/encoding
a video signal using the intra base prediction reduces a difference
in brightness between a current layer image and a base layer image,
if the base layer image performs down-sampling of the current layer
image or the current layer image is captured by another camera.
[0089] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the invention. Thus,
it is intended that the present invention cover the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
ADVANTAGEOUS EFFECTS
[0090] A method for decoding/encoding a video signal using an inter
layer prediction process according to the present invention uses a
variety of inter layer prediction methods by the macroblock types
of macroblocks of the current and base layers, and removes inter
layer redundancy, resulting in the increase of coding
efficiency.
BRIEF DESCRIPTION OF THE DRAWINGS
[0091] The accompanying drawings, which are included to provide a
further understanding of the invention, illustrate embodiments of
the invention and together with the description serve to explain
the principle of the invention.
[0092] In the drawings:
[0093] FIG. 1 is a flow chart illustrating a method for decoding a
video signal according to the present invention;
[0094] FIGS. 2.about.7 are conceptual diagrams illustrating the
video signal decoding method shown in FIG. 1 according to the
present invention;
[0095] FIG. 8 is a flow chart illustrating a method for encoding a
video signal according to the present invention; and
[0096] FIGS. 9.about.10 are conceptual diagrams illustrating the
video signal encoding method shown in FIG. 8 according to the
present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0097] Accordingly, the present invention is directed to a method
for decoding/encoding a video signal using an inter layer
prediction method that substantially obviates one or more problems
due to limitations and disadvantages of the related art.
[0098] An object of the present invention devised to solve the
problem lies on a method for decoding/encoding a video signal using
an inter layer prediction process.
[0099] The object of the present invention can be achieved by
providing a method for generating a method for decoding a video
signal including several layer information comprising: a) acquiring
a first prediction signal for a current block of an enhancement
layer and a residual signal based on at least a base layer block;
b) smoothing the sum of the first prediction signal and the
residual signal, and generating a second prediction signal for the
current block; and c) reconstructing the current block based on the
second prediction signal.
[0100] In another aspect of the present invention, there is
provided a method for encoding a video signal including several
layer information comprising: a) generating a second prediction
signal for a current layer using a first prediction signal for the
current layer and a residual signal for a base layer; and b)
encoding a residual signal between the second prediction signal and
a current macroblock.
* * * * *