JP4113696B2 - Lossless video encoding method, decoding method thereof, and apparatus thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to encoding and decoding techniques for efficiently transmitting and storing moving images.
[0002]
[Prior art]
As a lossless image encoding method, JPEG-LS or JPEG2000 lossless encoding modes are known. JPEG-LS encodes a difference between a prediction signal that is an output of a predictor and an original signal by using an intra-frame predictor. By using the intra-frame predictor, the coding efficiency is improved by utilizing the correlation of signals in the frame. In JPEG2000, lossless Wavelet conversion is performed, and Wavelet coefficients are encoded. Since the image signal is divided into spatial frequency bands by using Wavelet transform and encoding is performed for each band, spatial resolution scalability is provided.
[0003]
[Problems to be solved by the invention]
However, since both of the conventional systems are intended for still images, signal correlation between frames cannot be used when adapted to moving images. As lossy encoding of moving images, there is a method that performs spatial compensation in the subband region as a method that has spatial resolution scalability and uses inter-frame correlation, but motion compensation performs prediction in units of blocks. Encoding efficiency is not always good. Having spatial resolution scalability indicates that images of different spatial resolutions can be directly decoded from one encoded bitstream.
[0004]
An object of the present invention is to propose a moving image lossless encoding method, a decoding method thereof, and a device thereof having spatial resolution scalability and excellent encoding efficiency.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention provides a lossless encoding method for moving images, in which an original image is band-divided, and space-time adaptive prediction is performed by motion estimation for each divided band to generate a prediction residual signal. And encoding the prediction residual signal for each band and the motion vector used in the space-time adaptive prediction,
In the spatio-temporal adaptive prediction, a motion vector is obtained from the current frame and the reference frame by the block unit estimation means, and the target frame neighboring signal value of the current frame and the reference frame shifted by the shift means is used using the motion vector. When the correlation coefficient is calculated and the correlation coefficient is large, switching to the three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small , Switch to two-dimensional prediction in which prediction is performed using only the encoding target pixel neighborhood signal value of the current frame,
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. The moving image lossless encoding method is used as means.
[0006]
Alternatively, in a lossless decoding method for outputting a moving image, a prediction residual signal and a motion vector for each band encoded by the moving image lossless encoding method according to claim 1 are decoded, and a prediction residual for each band is decoded. When performing space-time adaptive prediction decoding for each band using a signal and the motion vector, and decoding a moving image by performing band synthesis on the space-time adaptive prediction decoded band,
The said time space adaptive prediction decoding, correlation coefficients and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal When the correlation coefficient is large, switch to 3D prediction, and when the correlation coefficient is small, switch to 2D prediction.
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Calculate prediction signals by switching multiple 3D predictors for each pixel,
A moving image lossless decoding method characterized by adding the prediction residual signal to the prediction signal and decoding the target signal.
[0007]
Alternatively, in a lossless encoding method for moving images, the original image is band-divided, and a prediction residual signal is obtained by performing space-time adaptive prediction by motion estimation in the lowest frequency band among the divided bands, When encoding the residual signal and the motion vector used in the spatiotemporal adaptive prediction and directly encoding the band other than the lowest frequency band,
In the spatio-temporal adaptive prediction, a motion vector is obtained from the current frame and the reference frame by the block unit estimation means, and the target frame neighboring signal value of the current frame and the reference frame shifted by the shift means is used using the motion vector. When the correlation coefficient is calculated and the correlation coefficient is large, switching to the three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small , Switch to two-dimensional prediction in which prediction is performed using only the encoding target pixel neighborhood signal value of the current frame,
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. The moving image lossless encoding method is used as means.
[0008]
Alternatively, in the lossless decoding method for outputting a moving image, among the signals encoded by the moving image lossless encoding method according to claim 3 , the prediction residual signal and the motion vector in the lowest frequency band are decoded and used. Perform space-time adaptive predictive decoding, directly decode bands other than the lowest frequency band, and perform band synthesis of the lowest frequency band subjected to space-time adaptive predictive decoding and the band other than the directly decoded lowest frequency band. When decoding video,
The said time space adaptive prediction decoding, correlation coefficients and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal When the correlation coefficient is large, switch to 3D prediction, and when the correlation coefficient is small, switch to 2D prediction.
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Calculate prediction signals by switching multiple 3D predictors for each pixel,
A moving image lossless decoding method characterized by adding the prediction residual signal to the prediction signal and decoding the target signal.
[0009]
Alternatively, in the lossless encoding method for moving images, the original image is band-divided, the first space-time adaptive prediction is performed in the divided lowest frequency band , and the second space-time adaptive prediction is performed in the other frequency bands. When calculating the prediction residual signal for each band and encoding the prediction residual signal for each band and the reference motion vector that is the motion vector of the lowest frequency band ,
The In the first space-time adaptive prediction, give the reference motion vector by a block unit estimating means from the reference frame and the current frame, by using the reference motion vector, and the space-time adaptive prediction of the second, the reference motion Using the motion vector based on the vector, the correlation coefficient of the signal near the pixel to be encoded for the current frame and the reference frame shifted by the shift means is calculated. Switch to three-dimensional prediction that uses the signal to be encoded pixel neighboring signal value of the frame and reference frame, and if the correlation coefficient is small, predict using only the signal to be encoded pixel neighboring signal value of the current frame Switch to two-dimensional prediction
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. The moving image lossless encoding method is used as means.
[0010]
Alternatively, in a lossless decoding method for outputting a moving image, a prediction residual signal for each band encoded by the moving image lossless encoding method according to claim 5 and a reference motion vector which is a motion vector in the lowest frequency band are decoded. and performs space-time adaptive prediction decoding for each said zone, when decoding a moving image by band synthesizing the band that has been said time space adaptive prediction decoding,
In the spatio-temporal adaptive prediction decoding related to the lowest frequency band, the reference motion vector is used, and in the spatio-temporal adaptive prediction related to other frequency bands, the shifted reference frame is decoded using the motion vector based on the reference motion vector. a-target pixel proximity signal value, calculates the correlation coefficient between the decoding target pixel sensor signal values consisting decoded signal of the current frame signal, when the correlation coefficient is large switched to 3D prediction, correlation If the number is small, switch to 2D prediction,
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, pixels from the decoded and decoded pixel neighboring signal value and a signal, decoded pixel near the signal value of the reference frame is shifted by using the motion vector of the current frame signal Each time a plurality of 3D predictors are switched to calculate a prediction signal,
A moving image lossless decoding method characterized by adding the prediction residual signal to the prediction signal and decoding the target signal.
[0015]
Similarly, in the lossless encoding apparatus for moving images, the present invention provides means for dividing an original image into bands, and means for obtaining a prediction residual signal by performing space-time adaptive prediction by motion estimation for each divided band. And means for encoding the prediction residual signal for each band and the motion vector used in the space-time adaptive prediction,
The means for obtaining the prediction residual signal by performing the spatiotemporal adaptive prediction obtains a motion vector from the current frame and the reference frame by the block unit estimation means, and uses the motion vector to shift the current frame and the reference frame shifted by the shift means. When the correlation coefficient of the encoding target pixel neighboring signal value is calculated and the correlation coefficient is large, the prediction is performed using the encoding target pixel neighboring signal value of the current frame and the reference frame. Switching, when the correlation coefficient is small, means for switching to two-dimensional prediction for performing prediction using only the pixel target signal neighborhood signal value of the current frame;
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus characterized by comprising:
[0016]
Alternatively, in a lossless decoding apparatus that outputs a moving image, means for decoding a prediction residual signal and a motion vector for each band encoded by the moving image lossless encoding apparatus according to claim 7 , and prediction for each band Means for performing space-time adaptive prediction decoding for each band using the residual signal and the motion vector, and means for band-combining the space-time adaptive prediction decoded band to decode a moving image,
Said time space adaptive prediction decoding to means, phase and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal Means for calculating the number of relationships, switching to three-dimensional prediction when the correlation coefficient is large, and switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Means for calculating a prediction signal by switching a plurality of three-dimensional predictors for each pixel;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal.
[0017]
Alternatively, in a lossless encoding apparatus for moving images, means for dividing an original image into bands and means for obtaining a prediction residual signal by performing space-time adaptive prediction by motion estimation in the lowest frequency band of the divided bands And means for encoding the prediction residual signal and the motion vector used in the space-time adaptive prediction, and directly encoding a band other than the lowest frequency band,
The spatio-temporal adaptive prediction means obtains a motion vector from the current frame and the reference frame by a block unit estimation means, and uses the motion vector to detect the vicinity of the encoding target pixel of the current frame and the reference frame shifted by the shift means. When the correlation coefficient of the signal value is calculated, and the correlation coefficient is large, switching to three-dimensional prediction in which prediction is performed using the signal value near the encoding target pixel in the current frame and the reference frame, and the correlation coefficient is small In this case, a means for switching to two-dimensional prediction for performing prediction using only the encoding target pixel neighborhood signal value of the current frame;
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus characterized by comprising:
[0018]
Alternatively, in a lossless decoding device that outputs a moving image, among the signals encoded by the moving image lossless encoding device according to claim 9 , the prediction residual signal and the motion vector in the lowest frequency band are decoded and the lowest Means for directly decoding a band other than the frequency band, means for performing space-time adaptive prediction decoding using the prediction residual signal of the lowest frequency band and the motion vector, and the lowest frequency band subjected to space-time adaptive prediction decoding Means for band-combining a band other than the lowest frequency band directly decoded and decoding a moving image,
Said time space adaptive prediction decoding to means, phase and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal Means for calculating the number of relationships, switching to three-dimensional prediction when the correlation coefficient is large, and switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Means for calculating a prediction signal by switching a plurality of three-dimensional predictors for each pixel;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal.
[0019]
Alternatively, in a lossless encoding device for moving images, a unit for band-dividing an original image and first space-time adaptive prediction in the divided lowest frequency band , and a second space-time in other frequency bands Means for performing adaptive prediction and obtaining a prediction residual signal for each band; and means for encoding a prediction residual signal for each band and a reference motion vector that is a motion vector of the lowest frequency band;
The first means for performing a space-time adaptive prediction, give the reference motion vector by a block unit estimating means from the reference frame and the current frame, by using the reference motion vector, and the space-time adaptive prediction of the second, When using the motion vector based on the reference motion vector to calculate the correlation coefficient of the signal to be encoded pixel neighboring signal values of the current frame and the reference frame shifted by the shift means , respectively , when the correlation coefficient is large Is switched to three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small, only the encoding target pixel neighboring signal value of the current frame is used. Means for switching to two-dimensional prediction using prediction,
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus characterized by comprising:
[0020]
Alternatively, in a lossless decoding device that outputs a moving image, the prediction residual signal for each band encoded by the moving image lossless encoding device according to claim 11 and a reference motion vector that is a motion vector in the lowest frequency band are decoded. a means for, and means for performing a space-time adaptive prediction decoding for each said zone, and means for decoding the moving image by band synthesizing the band that has been said time space adaptive prediction decoding,
The spatio-temporal adaptive predictive decoding means uses the reference motion vector for decoding related to the lowest frequency band, and uses a motion vector based on the reference motion vector for decoding related to the other frequency bands . Calculate the correlation coefficient between the decoding target pixel neighborhood signal value of the frame and the decoding target pixel neighborhood signal value consisting of the decoded signal of the signal in the current frame, and switch to three-dimensional prediction when the correlation coefficient is large Means for switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, pixels from the decoded and decoded pixel neighboring signal value and a signal, decoded pixel near the signal value of the reference frame is shifted by using the motion vector of the current frame signal Means for calculating a prediction signal by switching a plurality of three-dimensional predictors every time;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal.
[0025]
In the present invention, in order to realize spatial resolution scalability, an image signal is divided into spatial resolution bands, and encoding is performed for each band. For encoding, spatiotemporal adaptive prediction encoding is used to increase the encoding efficiency by switching between intra-frame prediction (two-dimensional prediction) and inter-frame prediction (three-dimensional prediction) for each pixel.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0027]
[First Embodiment]
FIG. 1 shows a basic configuration for realizing a moving picture coding method having spatial resolution scalability. In FIG. 1, 10 is a band dividing unit, 11 is a spatio-temporal adaptive prediction encoding unit provided for each divided band, and 12 is an entropy encoding unit.
[0028]
A moving picture encoding method as an operation example of the configuration of FIG. 1 will be described below. First, the input image signal is divided into a plurality of spatial resolution bands by the band dividing unit 10. Next, the residual signal generated by the space-time adaptive prediction encoding unit 11 is encoded by the entropy encoding unit 12 for each divided band.
[0029]
The band dividing unit 10 applies the octave division shown in FIG. 2 to the horizontal direction and the vertical direction of the image, respectively. In the octave division, the input signal can be divided into a plurality of bands by dividing the band one after another using a two-division filter, and finally the band is divided as shown in FIG.
[0030]
In FIG. 3, L represents a low frequency component, and H represents a high frequency component. The two-division filter used here and the band synthesis filter used on the decoding side are completely reconstructed filters in order to maintain reversibility.
[0031]
The space-time adaptive prediction encoding unit 11 performs prediction using the following equation.
[0032]
f (a0, a1, a2, a3, ..., b0, b1, b2, b3, ...)
However,
f: prediction function a0, a1, a2, a3,...: pixel value b0, b1, b2, b3,... of encoding target frame, reference frame pixel value. Frame, the rear frame, and both the front and rear frames, the reference frame needs to be decoded first on the decoder side. The position of the pixel used for prediction is determined under the following conditions. Let the position of the pixel to be encoded be (x, y) (x is the position in the horizontal direction and y is the position in the vertical direction). In the case of a frame to be encoded, it is a pixel that is decoded first in the vicinity and on the decoding side. For example, when decoding from the leftmost pixel of the first row to the right and then decoding the second row from left to right for each row, the position (xa, ya) of the pixel used for prediction is as follows: It is necessary to satisfy the conditions.
[0033]
y−y0 <ya <y and x−x0 <xa <x + x1
Or
ya = y and x−x2 <xa <x
However,
y0: Appropriate integers x0, x1, x2 that define the neighborhood in the vertical direction: Pixel position (xb, yb) used for prediction of an appropriate integer reference frame that defines the neighborhood in the horizontal direction satisfies the following conditions There is a need.
[0034]
y + vy-y3 <ya <y + vy + y4 and x + vx-x3 <xa <x + vx + x4
However,
y3, y4: Appropriate integers x3 and x4 for determining the vicinity of the vertical direction V3: Appropriate integers V (vx, vy) for determining the vicinity of the horizontal direction: Motion vector motion vector V (vx, vy) to the reference frame Is obtained by performing motion estimation on the reference frame.
[0035]
The entropy encoding unit 12 entropy-encodes the residual signal of each band and the motion vector used in the space-time adaptive prediction encoding unit 11 to create an encoded bitstream.
[0036]
FIG. 5 shows a basic configuration of a space-time adaptive predictive coding unit that realizes the space-time adaptive predictive coding method. In FIG. 5, 31 is a block unit motion estimation means, 32 is a shift means, 33 is a two-dimensional predictor, 34 is a motion estimation three-dimensional predictor, 35 is a correlation coefficient R calculation means, and 36 is a first decision branching means. , 37 is addition / subtraction means, and 38 is addition / subtraction means.
[0037]
As predictors, three types of two-dimensional predictors and seven types of three-dimensional predictors are prepared, and the predictors are switched by inter-frame correlation .
[0038]
The three-dimensional predictor is effective when the inter-frame correlation is strong, but there is a possibility that the residual signal becomes large when the inter-frame correlation is weak. Therefore, a method of switching to a two-dimensional predictor is adopted when the inter-frame correlation is weak. In order to switch between the two-dimensional predictor and the three-dimensional predictor, the correlation coefficient of the decoded signal in the vicinity of the encoding target pixel in the current frame and the reference frame is calculated. When the correlation coefficient is large, that is, when the waveform of the signal in the current frame and the signal in the reference frame are similar, the prediction accuracy is considered to improve, so that three-dimensional prediction is performed. In other cases, two-dimensional prediction is performed.
[0039]
A prediction method for each predictor and a specific switching method for the predictor will be described below. The prediction method of each predictor is as follows.
[0040]
Two-dimensional predictor 0 Predicted signal y = min (a, b) (1)
Two-dimensional predictor 1 Predicted signal y = max (a, b) (2)
Two-dimensional predictor 2 Predicted signal y = a + bc (3)
Three-dimensional predictor 3 Predicted signal y = min (a, x ′) (4)
Three-dimensional predictor 4 Prediction signal y = max (a, x ′) (5)
Three-dimensional predictor 5 Predicted signal y = a + x′−a (6)
Three-dimensional predictor 6 Predicted signal y = min (b, x ′) (7)
Three-dimensional predictor 7 Prediction signal y = max (b, x ′) (8)
Three-dimensional predictor 8 Predicted signal y = b + x′−b (9)
Three-dimensional predictor 9 Predicted signal y = (a + b + x ′) / 3 (10)
As shown in FIG. 7A, a, b, and c used here are decoded values of the upper, left, and upper right pixels adjacent to the pixel x to be encoded. a ′, b ′, and x ′ are the decoded values of the pixels of the reference frame, and are based on the motion vector (k, l) (k: horizontal direction, l: vertical direction) between the frame to be encoded and the reference frame. Determine the pixel location. The motion vector is calculated in advance by a block matching method or the like in units of small blocks of L × L pixels and transmitted as additional information. If the position of the pixel x to be encoded is (i, j), the position of x ′ is (i + k, j + l). Further, as shown in FIG. 7B, a ′ and b ′ are the pixels on the left side adjacent to x ′. As the reference frame, any one of a temporally forward frame, a backward frame, and a forward and backward frame is used. However, on the decoder side, the reference frame needs to be decoded first.
[0041]
When R ≦ T0 and c ≧ max (a, b), select 2D predictor 0 When R ≦ T0 and c ≦ min (a, b) Select 2D predictor 1 R ≦ T0 and min (a, b) b) If <c <max (a, b) Select 2D predictor 2 Select R> T0 and S> T1 and a ′ ≧ max (a, x ′) Select 3D predictor 3 R> T0 And when S> T1 and a ′ ≦ min (a, x ′), the three-dimensional predictor 4 is selected R> T0, S> T1, and min (a, x ′) <a ′ <max (a, x ′) In the case of selecting the three-dimensional predictor 5 In the case of R> T0 and S <−T1 and b ′ ≧ max (b, x ′), the three-dimensional predictor 6 is selected R> T0 and S <−T1 and b ′ ≦ min. In the case of (b, x ′), the three-dimensional predictor 7 is selected. In the case of R> T0, S <−T1, and min (b, x ′) <b ′ <max (b, x ′), the three-dimensional predictor 8 is selected. Select-option R> T0 and -T1 <3 dimensional predictor 9 For S <T1 where
R = aa ′ + bb ′ + cc ′ + dd ′ − (a + b + c + d) (a ′ + b ′ + c ′ + d ′) (11)
S = | x′−b ′ | − | x′−a ′ | (12)
T0, T1: Threshold values a, b, c, d, a ′, b ′, c ′, d ′, x ′: Decoded values of the pixels shown in FIG.
[0042]
Here, R is a correlation coefficient, and when R is larger than the threshold value T0, a three-dimensional predictor is selected. In other cases, a two-dimensional predictor is selected. This selection is actually performed in two stages. That is, the first decision branch means 36 in FIG. 5 performs the first decision branch based on the R value, and first switches between the two-dimensional predictor or the three-dimensional predictor to switch the two-dimensional predictor 33 or the three-dimensional predictor 34. The remaining second decision branch is performed to select one of the predictors 1 to 9.
[0043]
The switching method of the three predictors of the two-dimensional predictor has been proposed and is the same as the method adopted in the international standard JPEG-LS for still image lossless compression. When it is determined that there is an edge in the vertical direction and the horizontal method, prediction is performed using one pixel adjacent to each edge direction, and prediction is performed using three adjacent pixels in other cases.
[0044]
In the case of three-dimensional prediction as well as the two-dimensional predictor, adaptive prediction is performed in which the predictor is switched depending on the state of the neighborhood signal value of the pixel to be encoded. When it is determined that there is an edge in the vertical direction or the horizontal direction, prediction is performed using signals adjacent to each edge direction of the current frame and the reference frame. As for the edge direction, the difference absolute value | x′−a ′ | in the vertical direction of the reference frame is compared with the absolute difference value | x′−b ′ | in the horizontal direction, and a direction larger than the threshold T1 is determined as an edge. To do. S in the equation (12) is a difference value between them and is a parameter for determining the edge direction. When it is determined that the edge is a vertical edge for determining the edge direction, a prediction signal is selected in the same manner as the two-dimensional predictor with respect to the vertical signals of the current frame and the reference frame. The predictor is selected in the same manner for the edge in the horizontal direction. When it is determined that it is not an edge, the average value of three neighboring pixels is set as the predicted value.
[0045]
The addition / subtraction means 37 or 38 outputs a difference between the prediction signal output from the predictor and the original frame signal, that is, a prediction residual signal. The prediction residual signal is quantized by a quantizer (not shown). The quantized residual signal and the motion vector used in the three-dimensional predictor are input to the entropy encoding unit 12 in FIG. 1, and an encoded bit stream is output. When the quantization step of the quantizer is set to 1, the present encoding method is a lossless encoding method.
[0046]
[Second Embodiment]
FIG. 4 shows a basic configuration for realizing the decoding method for decoding the data encoded in the first embodiment. In FIG. 4, 20 is an entropy decoding unit, 21 is a space-time adaptive predictive decoding unit provided for each band, and 22 is a band synthesizing unit.
[0047]
A decoding method as an operation example of the configuration of FIG. 4 is shown below. First, the entropy decoding unit 20 obtains a motion vector and a prediction residual signal used for prediction from the encoded bit stream. Next, the encoded signal is decoded using the image signal and residual signal that have already been decoded by the space-time adaptive predictive encoding unit 21. Next, the band synthesizing unit 22 synthesizes the outputs of the spatiotemporal adaptive prediction encoding units 21 to decode the image.
[0048]
FIG. 6 shows a basic configuration of the space-time adaptive predictive decoding unit. In FIG. 6, 41 is a shift means, 42 is a two-dimensional predictor, 43 is an adder, 44 is a motion estimation three-dimensional predictor, 45 is an adder, 46 is a correlation coefficient R calculator, and 47 is a first determination. It is a branching means.
[0049]
The space-time adaptive predictive decoding method as the operation example of FIG. 6 is as follows. First, in order to determine whether to use the two-dimensional predictor 42 or the three-dimensional predictor 44, from the decoded signal of the reference intra-frame signal and the current intra-frame signal shifted by the shift means 41 using the motion vector, The correlation coefficient R is calculated by the correlation coefficient R calculation means 46. When the correlation coefficient R is larger than the threshold value T0, the first decision branching unit 47 switches to the motion estimation three-dimensional predictor 44 side to perform three-dimensional prediction, and otherwise, the two-dimensional predictor 42. Switch to the side and perform 2D prediction. The configuration of the two-dimensional predictor 42 and the motion estimation three-dimensional predictor 44 and the switching of a plurality of predictors prepared therein are the same as those in the first embodiment. The motion estimation three-dimensional predictor 44 generates a prediction signal using the decoded signal of the current intraframe signal and the reference intraframe signal shifted using the motion vector, and the adder 45 adds the residual signal to the prediction signal. Is added to restore the target signal of the current frame. The two-dimensional predictor 42 generates a prediction signal using the decoded signal of the signal in the current frame, and the adding unit 43 adds the residual signal to the prediction signal, thereby restoring the target signal of the current frame.
[0050]
[Third Embodiment]
In this embodiment, the spatio-temporal adaptive predictive coding unit 11 of the first embodiment estimates the motion of the target object in each band by the block matching method. In the block matching method, the following SAD (Sumof Absolute Difference) value is calculated in order to obtain a motion vector.
[0051]
SAD (k, l) = Σi _{= 1} ^L Σj _{= 1} ^L | x (i, j) −y (i + k, j + l) | (13)
Here, SAD (k, l) is calculated in the range of (k, l) -w <k, 1 <w (w is the window size), and the vector (k, l) giving the minimum SAD value moves. Selected as a vector. In order to improve the prediction accuracy of the three-dimensional predictor, SAD is usually calculated for each band. The calculation of SAD takes a considerable amount of time. Considering this, the following three simple encoding methods (1), (2), and (3) are proposed to reduce the calculation time while minimizing the decrease in encoding efficiency.
[0052]
(1) The inter-frame correlation and intra-frame correlation of the band-divided signal are stronger as the frequency is lower and weaker as the frequency is higher. Since signals other than the lowest frequency band have weak inter-frame correlation and intra-frame correlation, the effect of space-time adaptive prediction coding does not appear so significantly. Using this property, space-time adaptive predictive coding is applied only to the lowest frequency band. The calculation amount of SAD is extremely reduced, and the two-dimensional and three-dimensional prediction processing times are also reduced. The motion vector in the lowest frequency band and the prediction residual signal are entropy coded, and the signal other than the lowest frequency band is directly entropy coded.
[0053]
FIG. 8 shows a basic configuration diagram for realizing this method. In FIG. 8, 50 is a band dividing unit, 51 is a space-time adaptive prediction encoding unit for the lowest frequency band, and 52 is an entropy encoding unit 52. First, the input image signal is divided into a plurality of spatial resolution bands by the band dividing unit 50 . Next, a residual signal is generated by the spatio-temporal adaptive prediction encoding unit 51 only for the lowest frequency band among the divided bands, and entropy encoding unit 52 performs entropy encoding. The entropy encoding unit 52 directly encodes signals in other bands.
[0054]
(2) A motion vector is obtained by performing motion estimation only in the lowest frequency band. In other bands, space-time adaptive prediction encoding is performed using motion vectors based on the motion vector in the lowest frequency band. Since the movement of the target object does not change for each band, the movement of the high-frequency object and the movement of the low-frequency object should be equal. That is, it is assumed that the small block motion vectors existing in the same direction from the low range to the high range are the same. For example, the movements of the small blocks indicated by the arrows in FIG. However, the number of pixels doubles in the vertical and horizontal directions each time the band increases in one high region, so the motion vector in one high region is
(2k, 2l)
It becomes. The motion vector of the N stage high region is
(N × k, N × l)
It becomes.
[0055]
The basic configuration diagram for realizing this method is the same as that in FIG. 1, but the motion vector used in the space-time adaptive prediction encoding unit 11 for each band is a motion vector based on the motion vector in the lowest frequency band. Use. The motion vector in the lowest frequency band and the prediction residual signal in the entire band are entropy encoded by the entropy encoding unit 12.
[0056]
(3) When calculating SAD, it is performed from low to high. In the example of FIG. 3, the order is LL3->HL3->LH3->HH3->HL2->LH2->HH2->HL1->LH1-> HH1. First, SAD is calculated for each small block in the lowest frequency band. SAD
SAD (k, l)> T (threshold value) (14)
For the signals in the small blocks, it is determined that the inter-frame correlation is weak, and the two-dimensional prediction is performed without performing the spatiotemporal adaptive prediction process. In addition, the entropy coding is directly performed on the corresponding high-frequency small block signals without performing the space-time adaptive prediction coding.
[0057]
For a signal in a block that does not satisfy Expression (14), space-time adaptive prediction coding is performed as usual. In the subsequent high-band block, SAD
SAD (k, l)> Tx (threshold in high band. Threshold varies depending on band) (15)
In this case, it is determined that the correlation between frames is weak, and direct entropy coding is performed without performing space-time adaptive prediction coding. In addition, when the SAD of the corresponding low-frequency block already satisfies the equation (14), it is determined that the direct entropy encoding is performed, so the calculation of the SAD and the determination of the equation (15) Not performed.
[0058]
A small block that satisfies the conditions of equations (14) and (15) transmits a unique code LIMIT instead of a motion vector as additional information, and does not transmit additional information in the corresponding high-frequency small block. The motion vector, the unique code LIMIT, and the prediction residual signal are entropy encoded.
[0059]
The basic configuration diagram for realizing this method is the same as that in FIG. 1, but each space-time adaptive predictive encoder 11 has a function of calculating SAD from low to high in block unit motion estimation. And a function for determining whether to perform space-time adaptive predictive coding, a function for transmitting a unique code LIMIT, and the like. The entropy encoder 12 entropy-encodes the motion vector, the unique code LIMIT, a signal not subjected to space-time adaptive prediction encoding, or a prediction residual signal from each space-time adaptive prediction encoder 11.
[0060]
[Fourth Embodiment]
A simple decoding method of a signal encoded by a simple encoding method according to a third embodiment will be described.
[0061]
(1) FIG. 9 shows a basic configuration diagram for decoding a signal encoded by the simple encoding (1). In FIG. 9, 60 is an entropy decoding unit, 61 is a space-time adaptive prediction decoding unit for the lowest frequency band, and 62 is a band synthesizing unit.
[0062]
In this method, using the motion vector entropy-decoded by the entropy decoding unit 60 and the prediction residual signal, the spatio-temporal prediction decoding unit 61 decodes the signal in the lowest frequency band. Other bands are directly decoded by the entropy decoding unit 60 by entropy decoding. The band synthesizer 62 synthesizes the output of each band and decodes the image.
[0063]
(2) The basic configuration diagram for realizing the decoding method for decoding the signal encoded by the simple encoding (2) is the same as that in FIG. 4, but the spatio-temporal adaptive predictive decoding unit for each band. The motion vector used in 21 is a motion vector based on the motion vector in the lowest frequency band. That is, based on the motion vector (k, l) of the lowest frequency band entropy decoded by the entropy decoding unit 20, the motion vector of the N-stage high band is
(N × k, N × l)
Calculate according to Based on the result, the spatio-temporal adaptive predictive decoding unit 21 performs decoding processing for each band, and the band synthesizing unit 22 synthesizes the output of each band to decode the image.
[0064]
(3) The basic configuration diagram for realizing the decoding method for decoding the signal encoded by the simple encoding (3) is the same as that in FIG. 4, but the space-time adaptive predictive decoding unit for each band. 21, using the motion vector (k, l) of the lowest frequency band entropy decoded by the entropy decoding unit 20 and the prediction residual signal, the lowest frequency band to the highest frequency band (in the example of FIG. 3). LL3->HL3->LH3->HH3->HL2->LH2->HH2->HL1->LH1-> HH1) in order, and output by performing spatio-temporal adaptive predictive decoding processing, or entropy-decoded by the eigencode LIMIT Direct output of frequency band signals. The band synthesizer 22 synthesizes the output of each band and decodes the image.
[0065]
【The invention's effect】
As is apparent from the above description, according to the present invention, lossless encoding with high efficiency of moving images can be performed, and storage with a small disk capacity is possible. Furthermore, since it has spatial resolution scalability, it is possible to decode an image with a spatial resolution according to the performance and application of the image display device. When decoding from a low band to an arbitrary band, an image having a lower spatial resolution than the original image can be reproduced, and when all data is decoded, an image having the same resolution as the original image is reproduced. If you want to reproduce an image with a resolution lower than the original image depending on the accuracy and application of the image display device, you only need to decode up to the required bandwidth. If you perform decoding, the image is directly decoded from the encoded data. The processing time is shorter than when the resolution conversion is performed after the image having the same resolution as the original image is reproduced. Also, when transmitting an encoded bit stream, only the necessary data is transmitted, so the transmission rate is also reduced.
[Brief description of the drawings]
FIG. 1 is a diagram showing a basic configuration for realizing a moving picture coding method according to a first embodiment of the present invention.
FIG. 2 is a diagram for explaining octave division;
FIG. 3 is a diagram illustrating band division of an image.
FIG. 4 is a diagram showing a basic configuration for realizing a moving picture decoding method according to a second embodiment of the present invention.
FIG. 5 is a diagram illustrating a basic configuration of a spatiotemporal adaptive prediction encoding unit in the present invention.
FIG. 6 is a diagram illustrating a basic configuration of a spatiotemporal adaptive predictive decoding unit according to the present invention.
FIGS. 7A and 7B are diagrams illustrating signals used for prediction. FIGS.
FIG. 8 is a diagram showing a basic configuration for realizing simple encoding (1) according to a third embodiment of the present invention.
FIG. 9 is a diagram showing a basic configuration for realizing simple decoding (1) according to a fourth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Band division part 11 ... Spatio-temporal adaptive prediction encoding part 12 ... Entropy encoding part 20 ... Entropy decoding part 21 ... Spatio-temporal adaptive prediction decoding part 22 ... Band synthesis part 31 ... Block unit motion estimation means 32 ... Shift means 33 ... Two-dimensional predictor 34 ... Motion estimation three-dimensional predictor 35 ... Correlation coefficient R calculation means 36 ... First decision branching means 37 ... Addition / subtraction means 38 ... Addition / subtraction means 41 ... Shift means 42 ... Two-dimensional predictor 43 ... Addition unit 44 ... motion estimation three-dimensional predictor 45 ... addition unit 46 ... correlation coefficient R calculation unit 47 ... first decision branching unit 50 ... band division unit 51 ... spatio-temporal adaptive prediction encoding unit 52 ... entropy encoding unit 60 ... Entropy decoding unit 61 ... Spatio-temporal adaptive prediction decoding unit 62 ... Band synthesis unit

Claims (12)

In a lossless encoding method for a moving image, an original image is band-divided, and a prediction residual signal is obtained by performing space-time adaptive prediction by motion estimation for each of the divided bands to obtain a prediction residual signal for each band. And the motion vector used in the spatio-temporal adaptive prediction,
In the spatio-temporal adaptive prediction, a motion vector is obtained from the current frame and the reference frame by the block unit estimation means, and the target frame neighboring signal value of the current frame and the reference frame shifted by the shift means is used using the motion vector. When the correlation coefficient is calculated and the correlation coefficient is large, switching to the three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small , Switch to two-dimensional prediction in which prediction is performed using only the encoding target pixel neighborhood signal value of the current frame,
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. A moving image lossless encoding method. In the lossless decoding method which outputs a moving image, the prediction residual signal and the motion vector for each band encoded by the moving image lossless encoding method according to claim 1 are decoded, and the prediction residual signal for each band is decoded. When performing space-time adaptive prediction decoding for each band using the motion vector, and decoding a moving image by performing band synthesis on the space-time adaptive prediction decoded band,
The said time space adaptive prediction decoding, correlation coefficients and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal When the correlation coefficient is large, switch to 3D prediction, and when the correlation coefficient is small, switch to 2D prediction.
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Calculate prediction signals by switching multiple 3D predictors for each pixel,
A moving picture lossless decoding method comprising decoding the target signal by adding the prediction residual signal to the prediction signal. In a lossless encoding method for moving images, an original image is band-divided, and a prediction residual signal is obtained by performing space-time adaptive prediction by motion estimation in the lowest frequency band of the divided bands, and the prediction residual is obtained. When encoding a signal and a motion vector used in the space-time adaptive prediction and directly encoding a band other than the lowest frequency band,
In the spatio-temporal adaptive prediction, a motion vector is obtained from the current frame and the reference frame by the block unit estimation means, and the target frame neighboring signal value of the current frame and the reference frame shifted by the shift means is used using the motion vector. When the correlation coefficient is calculated and the correlation coefficient is large, switching to the three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small , Switch to two-dimensional prediction in which prediction is performed using only the encoding target pixel neighborhood signal value of the current frame,
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. A moving image lossless encoding method. 4. A lossless decoding method for outputting a moving image, wherein among the signals encoded by the moving image lossless encoding method according to claim 3, a prediction residual signal in the lowest frequency band and a motion vector are decoded and used in a spatio-temporal manner. Performs adaptive predictive decoding, directly decodes bands other than the lowest frequency band, and performs band synthesis of the lowest frequency band subjected to space-time adaptive predictive decoding and the band other than the directly decoded lowest frequency band. When decrypting
The said time space adaptive prediction decoding, correlation coefficients and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal When the correlation coefficient is large, switch to 3D prediction, and when the correlation coefficient is small, switch to 2D prediction.
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Calculate prediction signals by switching multiple 3D predictors for each pixel,
A moving picture lossless decoding method comprising decoding the target signal by adding the prediction residual signal to the prediction signal. In a lossless encoding method for moving images, the original image is divided into bands, and the first spatiotemporal adaptive prediction is performed in the divided lowest frequency band , and the second spatiotemporal adaptive prediction is performed in the other frequency bands. When obtaining a prediction residual signal for each band and encoding the prediction residual signal for each band and a reference motion vector that is a motion vector of the lowest frequency band ,
The In the first space-time adaptive prediction, give the reference motion vector by a block unit estimating means from the reference frame and the current frame, by using the reference motion vector, and the space-time adaptive prediction of the second, the reference motion Using the motion vector based on the vector, the correlation coefficient of the signal near the pixel to be encoded for the current frame and the reference frame shifted by the shift means is calculated. Switch to three-dimensional prediction that uses the signal to be encoded pixel neighboring signal value of the frame and reference frame, and if the correlation coefficient is small, predict using only the signal to be encoded pixel neighboring signal value of the current frame Switch to two-dimensional prediction
In the case of switching to the two-dimensional prediction, a prediction residual signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame,
When switching to the three-dimensional prediction, the prediction residual signal is calculated by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame. A moving image lossless encoding method. In the lossless decoding method for outputting a moving image, the prediction residual signal for each band encoded by the moving image lossless encoding method according to claim 5 and a reference motion vector which is a motion vector in the lowest frequency band are decoded . It performs space-time adaptive prediction decoding for each said zone, when decoding a moving image by band synthesizing the band that has been said time space adaptive prediction decoding,
In the spatio-temporal adaptive prediction decoding related to the lowest frequency band, the reference motion vector is used, and in the spatio-temporal adaptive prediction related to other frequency bands, the shifted reference frame is decoded using the motion vector based on the reference motion vector. a-target pixel proximity signal value, calculates the correlation coefficient between the decoding target pixel sensor signal values consisting decoded signal of the current frame signal, when the correlation coefficient is large switched to 3D prediction, correlation If the number is small, switch to 2D prediction,
In the case of switching to the two-dimensional prediction, a prediction signal is calculated by switching a plurality of two-dimensional predictors for each pixel from the decoding target pixel neighboring signal value including the decoded signal of the signal in the current frame,
When switched to the three-dimensional prediction, pixels from the decoded and decoded pixel neighboring signal value and a signal, decoded pixel near the signal value of the reference frame is shifted by using the motion vector of the current frame signal Each time a plurality of 3D predictors are switched to calculate a prediction signal,
A moving picture lossless decoding method comprising decoding the target signal by adding the prediction residual signal to the prediction signal. In a lossless encoding apparatus for moving images, means for dividing an original image into bands, means for performing space-time adaptive prediction by motion estimation for each divided band, obtaining a prediction residual signal, Means for encoding a prediction residual signal and a motion vector used in the space-time adaptive prediction;
The means for obtaining the prediction residual signal by performing the spatiotemporal adaptive prediction obtains a motion vector from the current frame and the reference frame by the block unit estimation means, and uses the motion vector to shift the current frame and the reference frame shifted by the shift means. When the correlation coefficient of the encoding target pixel neighboring signal value is calculated and the correlation coefficient is large, the prediction is performed using the encoding target pixel neighboring signal value of the current frame and the reference frame. Switching, when the correlation coefficient is small, means for switching to two-dimensional prediction for performing prediction using only the pixel target signal neighborhood signal value of the current frame;
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus comprising: A lossless decoding apparatus for outputting a moving image, wherein the prediction residual signal and motion vector for each band encoded by the lossless video encoding apparatus according to claim 7 are decoded, and the prediction residual for each band. Means for performing spatiotemporal adaptive prediction decoding for each band using a signal and the motion vector; and means for decoding a moving image by performing band synthesis on the spatiotemporal adaptive prediction decoded band;
Said time space adaptive prediction decoding to means, phase and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal Means for calculating the number of relationships, switching to three-dimensional prediction when the correlation coefficient is large, and switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Means for calculating a prediction signal by switching a plurality of three-dimensional predictors for each pixel;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal. In a lossless encoding apparatus for moving images, means for band-dividing an original image, means for obtaining a prediction residual signal by performing space-time adaptive prediction by motion estimation in the lowest frequency band of the divided bands, Means for encoding the prediction residual signal and the motion vector used in the spatiotemporal adaptive prediction and directly encoding a band other than the lowest frequency band;
The spatio-temporal adaptive prediction means obtains a motion vector from the current frame and the reference frame by a block unit estimation means, and uses the motion vector to detect the vicinity of the encoding target pixel of the current frame and the reference frame shifted by the shift means. When the correlation coefficient of the signal value is calculated, and the correlation coefficient is large, switching to three-dimensional prediction in which prediction is performed using the signal value near the encoding target pixel in the current frame and the reference frame, and the correlation coefficient is small In this case, a means for switching to two-dimensional prediction for performing prediction using only the encoding target pixel neighborhood signal value of the current frame;
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus comprising: 10. A lossless decoding apparatus that outputs a moving picture, wherein the prediction residual signal and the motion vector of the lowest frequency band are decoded from the signals encoded by the moving picture lossless encoding apparatus according to claim 9 , and the lowest frequency band is decoded. Means for directly decoding a band other than the above, means for performing space-time adaptive prediction decoding using the prediction residual signal of the lowest frequency band and the motion vector, and the lowest frequency band subjected to space-time adaptive prediction decoding and the direct Means for decoding a moving image by performing band synthesis with a band other than the decoded lowest frequency band,
Said time space adaptive prediction decoding to means, phase and decoded pixel near the signal value of the reference frame is shifted by using the motion vector, a decoded pixel near the signal value consisting decoded signal of the current frame signal Means for calculating the number of relationships, switching to three-dimensional prediction when the correlation coefficient is large, and switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, a decoded pixel near the signal value consisting decoded signal of the current frame signal, from the decoded pixel near the signal value of the reference frame is shifted by using the motion vector, Means for calculating a prediction signal by switching a plurality of three-dimensional predictors for each pixel;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal. In a lossless encoding apparatus for moving images, means for band-dividing an original image and first space-time adaptive prediction in the divided lowest frequency band , and second space-time adaptive prediction in other frequency bands was carried out, comprising means for obtaining a prediction residual signal for each band, and means for encoding a reference motion vector is a motion vector of the prediction residual signal and the outermost low-frequency band of each band-,
The first means for performing a space-time adaptive prediction, give the reference motion vector by a block unit estimating means from the reference frame and the current frame, by using the reference motion vector, and the space-time adaptive prediction of the second, When using the motion vector based on the reference motion vector to calculate the correlation coefficient of the signal to be encoded pixel neighboring signal values of the current frame and the reference frame shifted by the shift means , respectively , when the correlation coefficient is large Is switched to three-dimensional prediction in which prediction is performed using the encoding target pixel neighboring signal values of the current frame and the reference frame, and when the correlation coefficient is small, only the encoding target pixel neighboring signal value of the current frame is used. Means for switching to two-dimensional prediction using prediction,
In the case of switching to the two-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of two-dimensional predictors for each pixel from the encoding target pixel vicinity signal value of the current frame;
In the case of switching to the three-dimensional prediction, a means for calculating a prediction residual signal by switching a plurality of three-dimensional predictors for each pixel from the encoding target pixel neighboring signal values of the current frame and the reference frame , A moving image lossless encoding apparatus comprising: 12. A lossless decoding apparatus for outputting a moving picture, wherein the means for decoding a prediction residual signal for each band and a reference motion vector , which is a motion vector in the lowest frequency band, encoded by the moving picture lossless encoding apparatus according to claim 11. When, and means for decoding and means for performing a space-time adaptive prediction decoding for each said zone, a moving image and band synthesizing the band that has been said time space adaptive prediction decoding,
The spatio-temporal adaptive predictive decoding means uses the reference motion vector for decoding related to the lowest frequency band, and uses a motion vector based on the reference motion vector for decoding related to the other frequency bands . Calculate the correlation coefficient between the decoding target pixel neighborhood signal value of the frame and the decoding target pixel neighborhood signal value consisting of the decoded signal of the signal in the current frame, and switch to three-dimensional prediction when the correlation coefficient is large Means for switching to two-dimensional prediction when the correlation coefficient is small;
Means for calculating a prediction signal by switching a plurality of two-dimensional predictors for each pixel from a decoding target pixel neighborhood signal value made up of a decoded signal of a signal in the current frame when switched to the two-dimensional prediction; ,
When switched to the three-dimensional prediction, pixels from the decoded and decoded pixel neighboring signal value and a signal, decoded pixel near the signal value of the reference frame is shifted by using the motion vector of the current frame signal Means for calculating a prediction signal by switching a plurality of three-dimensional predictors every time;
And a means for decoding the target signal by adding the prediction residual signal to the prediction signal.

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