KR20230161389A - Method and apparatus for deciding boundary filtering strength of deblocking filtering - Google Patents

Abstract

The present invention relates to a method and apparatus for determining the boundary filtering strength of deblocking filtering. The method of determining the boundary filtering strength according to the present invention includes determining a partition boundary of a PU (Prediction Unit) and the boundary filtering strength of deblocking filtering. It includes determining (bS), and the boundary filtering strength of the deblocking filtering may be determined based on the partition boundary of the PU.

Description

Method and apparatus for determining boundary filtering strength of deblocking filtering {METHOD AND APPARATUS FOR DECIDING BOUNDARY FILTERING STRENGTH OF DEBLOCKING FILTERING}

The present invention relates to video compression technology, and more specifically to a deblocking filtering method and device.

Recently, broadcasting services with HD (High Definition) resolution (1280x1024 or 1920x1080) are expanding not only domestically but also globally.

Accordingly, many users are becoming accustomed to high-resolution, high-definition images, and in line with this, many organizations are accelerating the development of next-generation imaging devices.

In addition, as interest in UHD (Ultra High Definition), which has a resolution more than four times that of HDTV, has increased along with HDTV, video standardization organizations have recognized the need for compression technology for higher resolution, high-quality video.

There is an urgent need for a new standard that can achieve significant gains in terms of frequency band and storage while maintaining the same picture quality through higher compression efficiency than H.264/AVC currently used in HDTVs, mobile phones, and Blu-ray players.

Currently, MPEG (Moving Picture Experts Group) and VCEG (Video Coding Experts Group) are jointly developing HEVC (High Efficiency Video Coding), a next-generation video codec. The goal is to encode with twice the compression efficiency. This can provide high-definition video at a lower frequency than today, not only in HD and UHD video, but also in 3D broadcasting and mobile communication networks.

The purpose of the present invention is to provide a method and device that can eliminate or reduce blocking phenomenon in video encoding and decoding processes.

The purpose of the present invention is to provide a method and device for determining boundary filtering strengths differently depending on the characteristics of blocks in deblocking filtering performed during video encoding or decoding.

The purpose of the present invention is to provide a method and device for determining boundary filtering strength differently depending on whether or not it is a PU partition boundary in deblocking filtering.

The present invention provides a method and device that determines the strength of deblocking filtering according to the characteristics of the block (e.g., whether it is a PU partition boundary), thereby enabling adjustment of the filtering strength for PUs that have the same motion information by motion information compression. The purpose is to provide

One embodiment of the present invention is a method for determining boundary filtering of deblocking filtering, and the boundary filtering strength (bS) of deblocking filtering can be determined based on the partition type (PU type) of the CU.

At this time, if at least one of the absolute values of the difference between the motion vectors is 4 or more, or the reference frame in motion compensation is different, or is a PU partition boundary, the boundary filtering strength (bS) is determined to be 1, and on the other hand, the motion vector If the absolute values of the differences are both less than 4 and the reference frames in motion compensation are the same and are not PU partition boundaries, the boundary filtering strength (bS) can be determined to be 0.

The filtering strength (bS) may be determined in the parsing step. At this time, the determined filtering strength (bS) can be stored and used in the deblocking filtering process after the entire frame has been decoded.

Another embodiment of the present invention is a boundary filtering determination device for deblocking filtering, comprising: a boundary filtering strength determination unit for determining boundary filtering strengths for two adjacent blocks; and a filtering application unit configured to apply filtering to the pixel values of the two blocks according to the boundary filtering strength output from the boundary filtering strength determination unit.

The boundary filtering strength determination unit determines whether at least one block among two adjacent blocks is intra-encoded, and when it is determined that both blocks are not intra-encoded, at least one block among the two blocks is orthogonal. It is determined whether the two blocks have a transform coefficient, and if it is determined that neither of the two blocks has an orthogonal transform coefficient, at least one of the absolute values of the difference between the x-axis component and the y-axis component of the motion vector for the two blocks is 4 or more, or it is determined whether motion compensation is performed based on a different reference frame or a PU partition boundary, and the absolute values of the differences between the motion vectors are both less than 4, and the motion compensation is based on the same reference frame. The boundary filtering strength can be determined by considering whether the filtering is performed and whether it is a PU partition boundary.

At this time, if at least one of the absolute values of the difference between the motion vectors is 4 or more, or the reference frame in motion compensation is different, or is a PU partition boundary, the boundary filtering strength (bS) is determined to be 1, and on the other hand, the motion vector If the absolute values of the differences are both less than 4 and the reference frames in motion compensation are the same and are not PU partition boundaries, the boundary filtering strength (bS) can be determined to be 0.

The filtering strength (bS) may be determined in the parsing unit. In this case, the parsing unit can determine and store the filtering strength (bS), and the stored filtering strength (bS) can be used in the deblocking filtering process after the entire frame is decoded.

Another embodiment of the present invention is a deblocking filtering method, which includes the steps of parsing from a bitstream, determining a filtering strength (bS) through the parsed information, and decoding a frame. A step of deblocking and filtering the currently decoded frame using the filtering strength (bS) obtained by the parsing unit.

According to the present invention, blocking phenomenon can be eliminated or reduced in the video encoding and decoding process.

According to the present invention, coding efficiency can be increased by determining the boundary filtering strength differently depending on the characteristics of the block in deblocking filtering performed during the video encoding or decoding process.

According to the present invention, in deblocking filtering, the boundary filtering strength can be determined differently depending on whether it is a PU partition boundary.

According to the present invention, the strength of deblocking filtering is determined according to the characteristics of the block (e.g., whether it is a PU partition boundary), thereby making it possible to adjust the filtering strength for PUs that have the same motion information by motion information compression. .

1 is a block diagram showing the configuration of a video encoding device according to an embodiment of the present invention.
Figure 2 is a block diagram showing the configuration of a video decoding device according to another embodiment of the present invention.
Figure 3 is a diagram schematically explaining compression of spatial motion information and bS set accordingly.
Figure 4 is a flowchart schematically explaining an example of a method for determining bS based on the partition type of the CU.
Figure 5 is a diagram schematically explaining the relationship between block p and block q.
Figure 6 is a diagram schematically explaining an example of a method for determining bS of deblocking filtering in the parsing unit.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In describing the embodiments of the present specification, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present specification, the detailed description will be omitted.

When a component is said to be “connected” or “connected” to another component, it is understood that it may be directly connected or connected to the other component, but that other components may exist in between. It should be. In addition, the description of “including” a specific configuration in the present invention does not exclude configurations other than the configuration, and means that additional configurations may be included in the practice of the present invention or the scope of the technical idea of the present invention.

Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component, and similarly, the second component may also be named a first component without departing from the scope of the present invention.

Additionally, the components appearing in the embodiments of the present invention are shown independently to show different characteristic functions, and this does not mean that each component is comprised of separate hardware or a single software component. That is, each component is listed and included as a separate component for convenience of explanation, and at least two of each component can be combined to form one component, or one component can be divided into a plurality of components to perform a function, and each of these components can perform a function. Integrated embodiments and separate embodiments of the constituent parts are also included in the scope of the present invention as long as they do not deviate from the essence of the present invention.

Additionally, some components may not be essential components that perform essential functions in the present invention, but may simply be optional components to improve performance. The present invention can be implemented by including only essential components for implementing the essence of the present invention excluding components used only to improve performance, and a structure including only essential components excluding optional components used only to improve performance. is also included in the scope of rights of the present invention.

1 is a block diagram showing the configuration of a video encoding device according to an embodiment of the present invention.

Referring to FIG. 1, the image encoding device 100 includes a motion prediction unit 111, a motion compensation unit 112, an intra prediction unit 120, a switch 115, a subtractor 125, and a conversion unit 130. , a quantization unit 140, an entropy encoding unit 150, an inverse quantization unit 160, an inverse transform unit 170, an adder 175, a filter unit 180, and a reference picture buffer 190.

The image encoding device 100 may encode an input image in intra mode or inter mode and output a bitstream. In the case of intra mode, the switch 115 may be switched to intra, and in the case of inter mode, the switch 115 may be switched to inter. The image encoding apparatus 100 may calculate a prediction block for an input block of an input image and then encode the residual between the input block and the prediction block.

The intra mode is defined as an intra-screen prediction mode, the inter mode is an inter-screen prediction mode, the intra prediction unit 120 is an intra-screen prediction unit, and the motion prediction unit 111 and motion compensation unit 112 are defined as an inter-screen prediction unit. can be used.

In the case of intra mode, the intra prediction unit 120 may perform spatial prediction using pixel values of already encoded blocks surrounding the current block to calculate a prediction block.

In the case of inter mode, the motion prediction unit 111 can obtain a motion vector by finding an area that best matches the input block in the reference image stored in the reference picture buffer 190 during the motion prediction process. The motion compensation unit 112 may calculate a prediction block by performing motion compensation using a motion vector.

The subtractor 125 may calculate a residual block by the difference between the input block and the calculated prediction block. The transform unit 130 may perform transform on the residual block and output a transform coefficient. Here, the transformation coefficient may mean a coefficient value calculated by performing transformation on the residual block and/or the residual signal. Hereinafter, in this specification, a quantized transform coefficient level calculated by applying quantization to the transform coefficient may also be referred to as a transform coefficient.

The quantization unit 140 may quantize the input transform coefficient according to the quantization parameter and output a quantized transform coefficient level.

The entropy encoding unit 150 may perform entropy encoding based on values calculated by the quantization unit 140 or encoding parameter values calculated during the encoding process, and output a bit stream.

When entropy coding is applied, a small number of bits are allocated to symbols with a high probability of occurrence and a large number of bits are allocated to symbols with a low probability of occurrence to represent symbols, so that the bits for the symbols to be encoded are expressed. The size of the column may be reduced. Therefore, the compression performance of video encoding can be improved through entropy coding. The entropy encoding unit 150 may use encoding methods such as exponential gollomb, context-adaptive variable length coding (CAVLC), and context-adaptive binary arithmetic coding (CABAC) for entropy encoding.

Since the video encoding device according to the embodiment of FIG. 1 performs inter predictive coding, that is, inter-screen predictive coding, the currently encoded video needs to be decoded and stored to be used as a reference video. Therefore, the quantized coefficient is inversely quantized in the inverse quantization unit 160 and inversely transformed in the inverse transformation unit 170. The inverse-quantized and inverse-transformed coefficients are added to the prediction block through the adder 175, and a reconstructed block is calculated.

The restored block passes through the filter unit 180, and the filter unit 180 applies at least one of a deblocking filter, Sample Adaptive Offset (SAO), and Adaptive Loop Filter (ALF) to the restored block or restored picture. can do. The restored block that has passed through the filter unit 180 may be stored in the reference picture buffer 190.

Figure 2 is a block diagram showing the configuration of a video decoding device according to another embodiment of the present invention.

Referring to FIG. 2, the image decoding device 200 includes an entropy decoding unit 210, an inverse quantization unit 220, an inverse transform unit 230, an intra prediction unit 240, a motion compensation unit 250, and an adder ( 255), a filter unit 260, and a reference picture buffer 270.

The image decoding device 200 may receive a bitstream output from an encoder, perform decoding in intra mode or inter mode, and output a reconstructed image, that is, a reconstructed image. In the case of intra mode, the switch may be converted to intra, and in the case of inter mode, the switch may be converted to inter. The image decoding device 200 obtains a reconstructed residual block from the input bitstream, calculates a prediction block, and then adds the reconstructed residual block and the prediction block to produce a reconstructed block, that is, a restored block. .

The entropy decoding unit 210 may entropy decode the input bitstream according to a probability distribution and calculate symbols including symbols in the form of quantized coefficients. The entropy decoding method is similar to the entropy encoding method described above.

When the entropy decoding method is applied, a small number of bits are allocated to symbols with a high probability of occurrence and a large number of bits are allocated to symbols with a low probability of occurrence to represent the symbols, thereby reducing the size of the bit string for each symbol. can be reduced. Therefore, the compression performance of video decoding can be improved through the entropy decoding method.

The quantized coefficients are inversely quantized in the inverse quantization unit 220 and inversely transformed in the inverse transformation unit 230. As a result of the inverse quantization/inverse transformation of the quantized coefficients, a restored residual block can be calculated.

In the case of intra mode, the intra prediction unit 240 may perform spatial prediction using pixel values of already decoded blocks surrounding the current block to calculate a prediction block. In the inter mode, the motion compensation unit 250 can calculate a prediction block by performing motion compensation using a motion vector and a reference image stored in the reference picture buffer 270.

The restored residual block and the prediction block are added through an adder 255, and the added block may pass through a filter unit 260. The filter unit 260 may apply at least one of a deblocking filter, SAO, and ALF to a restored block or a restored picture. The filter unit 260 may output a reconstructed image, that is, a restored image. The reconstructed image can be stored in the reference picture buffer 270 and used for inter prediction.

Methods for improving the prediction performance of an encoding/decoding device include a method of increasing the accuracy of interpolation images and a method of predicting difference signals. Here, the difference signal is a signal that represents the difference between the original image and the predicted image. In the present invention, “difference signal” can be used instead of “difference signal”, “residual block” or “difference block” depending on the context, and those skilled in the art will not be able to influence the idea and essence of the invention. You will be able to distinguish this within the range that is not given.

In embodiments of the present invention, the terms coding unit (CU), prediction unit (PU), and transformation unit (TU) may be used as units for processing images.

The encoding unit is an image processing unit that performs encoding/decoding and may include information used to encode or decode the samples of the encoding block and the encoding block, which is a block unit set of luminance samples or chrominance samples on which encoding/decoding is performed.

A prediction unit is an image processing unit that performs prediction and may include a prediction block, which is a block-unit set of luminance samples or chrominance samples on which prediction is performed, and information used to predict samples of the prediction block. A coding block may be divided into a plurality of prediction blocks.

A transformation unit is an image processing unit that performs transformation and may include a transformation block, which is a block unit set of luminance samples or chrominance samples on which transformation is performed, and information used to transform samples of the transformation block. A coding block may be divided into a plurality of transform blocks.

Hereinafter, in the embodiments of the present invention, unless specifically indicated, block and unit may be interpreted as having the same meaning.

Additionally, the current block may refer to a block on which specific image processing is performed, such as a prediction block on which prediction is currently performed or a coding block on which encoding is currently performed. For example, when one coding block is split into two prediction blocks, the block on which prediction is performed among the split prediction blocks can be referred to as a current block.

In an embodiment of the present invention, the video encoding method and video decoding method, which will be described later, can be performed in each component included in the video encoder and video decoder described above in FIGS. 1 and 2. The meaning of the component part may include not only a hardware meaning but also a software processing unit that can be performed through an algorithm.

Meanwhile, the importance of memory is increasing in encoding/decoding, and as a result, a method of compressing and storing temporal motion information and/or a method of compressing and storing spatial motion information can be used.

Compression of spatial motion information is a method of having only 2 or 1 motion information depending on the depth when the current CU (Coding Unit) is divided into 4 PU blocks.

In this case, the setting of the boundary filtering strength (bS) of deblocking filtering (hereinafter referred to as ‘bS’ for convenience of explanation) may be affected.

Figure 3 is a diagram schematically explaining compression of spatial motion information and bS set accordingly.

FIG. 3 illustrates the case where the CU 300 is currently divided into two PUs 310 and 320 as an example.

Referring to FIG. 3, when the current CU (300) is divided into PU0 (310) indicated by the partition index PartIdx = 0 and PU1 (320) indicated by the partition index PartIdx = 1, the space Due to optimal motion information compression, PU0 (310) and PU1 (320) may have the same motion information.

Therefore, when determining the bS of deblocking filtering, since the motion information for two PUs, that is, PU0 (310) and PU1 (320), is the same, the bS of deblocking filtering can be determined to be ‘0’.

Originally, since the two PUs have different motion information, the bS of deblocking filtering should be set to ‘1’, but the bS of deblocking filtering is set to ‘0’, which may affect subjective image quality.

The present invention proposes a method for determining bS of deblocking filtering.

The present invention determines bS differently depending on whether it is a PU partition boundary or not when applying deblocking filtering when encoding or decoding a video. Therefore, according to the present invention, it is possible to adjust the bS value for PUs that have the same motion information through motion information compression.

For example, when determining bS, (1) at least one of the absolute values of the difference between motion vectors is 4 or more, or (2) the reference frames in motion compensation are different, or (3) the PU partition boundary is determined to determine bS. In the case of an edge, bS can be determined to be 1.

On the other hand, if (i) the absolute values of the differences in motion vectors are both less than 4 and (ii) the reference frames in motion compensation are the same and (iii) they are not PU partition boundaries, that is, (i), (ii), ( If iii) are all satisfied, bS can be determined to be 0.

According to the present invention, bS of deblocking filtering may be determined based on the partition type (PU type) of the CU, and the boundary filtering strength (bS) of deblocking filtering may be determined and stored in the parsing unit.

Hereinafter, each method will be described in detail with reference to the drawings.

Method based on CU partition type (PU type)

According to an embodiment of the present invention, bS of deblocking filtering can be determined based on the partition type of the CU, for example, the type of PU.

Figure 4 is a flowchart schematically explaining an example of a method for determining bS based on the partition type of the CU.

Referring to FIG. 4, in order to determine the boundary filtering strength (bS), it is first determined whether at least one block among adjacent blocks p and q has been intra-encoded (S410). Here, that block p or q is intra-coded or inter-coded may mean that block p or q is an intra-coded macroblock, CU, PU, or TU, or a block belonging to any one of these.

Figure 5 is a diagram schematically explaining the relationship between block p and block q.

Referring to FIG. 5(a), when the boundary 500 is a horizontal edge, block p (510) represents a block located to the left of the block boundary 500, and block q (520) represents the block boundary ( 500) indicates the block located on the right.

Referring to FIG. 5(b), when the boundary 530 is a vertical edge, block p (540) represents a block located above the block boundary 530, and block q (550) represents the block boundary ( 530) indicates the block located below.

As a result of the determination in step S410, if there is one or more intra-coded blocks among blocks p and q, the process proceeds to the 'INTRA MODE' step. Conversely, if both blocks p and q are inter-coded, the process proceeds to the 'inter mode' step. Proceed to the ‘(INTER MODE)’ stage.

Here, inter coding is predictive coding that uses the image of a restored (reconstructed) frame (picture) whose time is different from the current frame (picture) as a reference frame (picture), and intra coding is the image of a neighboring block within the current frame (picture). It is predictive coding using .

In the intra mode stage, that is, when it is determined that there is at least one intra-encoded block among blocks p and q, it is determined whether the boundary of blocks p and q matches the boundary of the CU (S440).

If the boundaries of blocks p and q coincide with the boundaries of the CU, bS is determined to be 4. On the other hand, if the boundary of blocks p and q is not the boundary of the CU, bS is determined to be 3.

If bS is 4, the strongest filtering is applied in the subsequent filtering application procedure, and the smaller the bS value, the weaker the strength of filtering.

In the inter mode stage, that is, when both blocks p and q are determined to be inter-encoded blocks, the boundary of blocks p and q is the boundary of the TU (Transform Unit), and at least one of blocks p and q has an orthogonal transform coefficient. determine whether or not (S420).

Orthogonal transform coefficients are also called coded coefficients or non-zero transform coefficients.

As a result of the determination, if the boundary of blocks p and q is the boundary of the TU and there is one or more blocks with orthogonal transformation coefficients, bS is determined to be 2. On the other hand, unless the boundary of blocks p and q is the boundary of the TU and there is one or more blocks with orthogonal transformation coefficients, the process proceeds to the next step.

In the next step, for blocks p and q, whether the absolute value of the difference between one component of the motion vector, that is, the x-axis component or the y-axis component, is equal to or greater than 4, and/or the reference frame in motion compensation is different, and/or PU Determine whether it is a partition boundary (S430).

Here, 'different reference frames' includes both that the reference frames themselves are different and that the number of reference frames is different.

If at least one of the absolute values of the difference between the motion vectors is 4 or more, or the reference frames in motion compensation are different, or is a PU partition boundary, bS is determined to be 1.

On the other hand, if the absolute values of the differences between the motion vectors are all less than 4 and the reference frames in motion compensation are the same and are not PU partition boundaries, bS is determined to be 0. bS of 0 indicates that no filtering is performed in the filtering application procedure.

Meanwhile, the method for determining bS can be determined based on various conditions as well as PU partition boundaries. For example, bS can be determined by applying at least one of conditions 1 to 3 below.

1. If the target boundary is a PU partition boundary, bS can be determined as 1.

2. If the current CU has the maximum depth and the target boundary is the PU partition boundary of that CU, bS can be determined to be 1. Here, execution may be performed if the depth of the current CU is not only the maximum depth but also a randomly determined depth.

3. If the boundaries of blocks p and q, which are target boundaries, are the boundaries of TU (Transform Unit), bS is determined to be 1.

4. If the current CU is at the maximum depth, bS for the boundary (or internal boundary) is determined to be 0.

In addition, several methods for determining bS can be applied.

How to determine bS in the parsing section

According to the present invention, the parsing unit of the decoding device can determine bS of deblocking filtering and store the determined bS.

Figure 6 is a diagram schematically explaining an example of a method for determining bS of deblocking filtering in the parsing unit.

Referring to FIG. 6, the decoder 600 includes a parsing and bS determination unit 610, a decoding unit 640, and a deblocking filtering unit 650.

The parsing and bS determination unit 610 may include a parsing unit 620 and a bS determination unit 630.

When the bitstream transmitted from the encoder is input to the decoder 600, the parsing unit 620 parses it to obtain necessary information.

The bS determination unit 630 may determine bS based on information obtained through parsing. At this time, the bS determination unit 630 may determine bS in the same manner as described in FIG. 4. Therefore, the information obtained by parsing in the parsing unit 620 determines whether p is intra-coded, whether q is intra-coded, whether the edge between p and q is a TU edge, whether p contains an encoded coefficient, and whether q is encoded. information about whether the difference between the components of the motion vector for blocks p and q is equal to or greater than 4, whether p and q have different reference frames, and whether the edge between p and q is a PU partition boundary. Includes.

The bS determined in the bS determination unit 630 is transmitted to the deblocking filtering unit 650.

The decryption unit 640 performs decryption based on the parsed information and outputs a restored block. A specific method of generating a restoration block is as described in FIG. 2.

The deblocking filtering unit 650 performs deblocking filtering using bS determined by the bS determination unit 630.

The deblocking filter unit 650 can determine the area to which the deblocking filter will be applied. Specifically, when the minimum unit to which the deblocking filter is applied is an 8x8 block, the boundary of the block can be derived by considering horizontal edges and vertical edges. The deblocking filtering unit 650 can determine whether to filter or what filtering to apply based on bS for the boundary of the block. The deblocking filtering unit 650 selects a filter to be applied to the edge of the block. Filters can be divided into strong filters and weak filters. The filter may be selected according to the bS value, quantization parameter, deblocking filtering parameter, etc.

Meanwhile, here, ‘applying a deblocking filter to the block edge’ means that the deblocking filter is applied to certain samples on the left and right (e.g., certain samples in p and q) bordering the block edge.

In the example of FIG. 6, each functional unit is configured to clarify the understanding of the present invention, but the present invention is not limited thereto. For example, the parsing and filtering strength determination unit 610 may correspond to the entropy decoding unit of FIG. 2 or may be configured as a separate parsing unit. Additionally, the deblocking filtering unit 650 may correspond to the filter unit of FIG. 2. Additionally, the decoding unit 640 may correspond to the remaining functional units excluding the entropy decoding unit and the filter unit in FIG. 2.

In addition, in FIG. 6, bS is determined in the bS determination unit 640, but when bS is not determined in the parsing unit but is determined in the filtering unit, the filtering unit derives the boundary to which deblocking filtering will be applied and then determines the boundary for each boundary. After setting bS. Depending on bS and/or other filtering parameters, it is possible to determine whether to apply deblocking filtering and which deblocking filtering (weak filtering, strong filtering) to apply.

In this specification, the present invention has been described using terms such as frame and reference frame, but this is for convenience of explanation. A (reference) frame may be used in the same sense as a (reference) picture, and in the present invention, a frame is referred to as a picture. Note that the technical idea of the present invention can be applied the same even when replaced with .

In the above-described exemplary system, the methods are described on a flowchart basis as a series of steps or blocks; however, the invention is not limited to the order of the steps, and some steps may occur simultaneously or in a different order than other steps as described above. You can. Additionally, the above-described embodiments include examples of various aspects. Accordingly, the present invention is intended to include all other substitutions, modifications and changes falling within the scope of the following claims.

In the description of the present invention so far, when it is mentioned that one component is “connected” or “connected” to another component, the other component is directly connected or connected to the other component. However, it should be understood that other components may exist between the above two components. On the other hand, when it is mentioned that one component is “directly connected” or “directly connected” to another component, it should be understood that no other components exist between the two components.

Claims (2)

determining a block boundary to which a deblocking filter will be applied;
determining a boundary filtering strength for the block boundary; and
Applying the deblocking filter to the block boundary based on the boundary filtering strength,
The step of determining the boundary filtering strength is,
Determine the value of the boundary filtering strength using whether the block boundary is a partition boundary of a prediction block and whether the block boundary is a partition boundary of a transform block,
If the depth of the coding block is the maximum depth, the inner boundary of the coding block is not filtered,
The prediction block and the transform block are each divided from the coding block,
An image decoding method, characterized in that the prediction block is decoded in one of intra mode and inter mode.
determining a block boundary to which a deblocking filter will be applied;
determining a boundary filtering strength for the block boundary; and
Applying the deblocking filter to the block boundary based on the boundary filtering strength,
The step of determining the boundary filtering strength is,
Determine the value of the boundary filtering strength using whether the block boundary is a partition boundary of a prediction block and whether the block boundary is a partition boundary of a transform block,
If the depth of the coding block is the maximum depth, the inner boundary of the coding block is not filtered,
The prediction block and the transform block are each divided from the coding block,
An image encoding method, characterized in that the prediction block is encoded in one of intra mode and inter mode.