KR102601705B1 - Method of piecewise linear scaling of geometry atlas and apparatus using the same - Google Patents

Abstract

A method for partially linear scaling a geometric atlas according to an embodiment of the present invention includes generating min-max normalized depth values; and generating geometry atlases by scaling the depth values corresponding to slopes of a plurality of linear sections.

Description

Partial linear scaling method of geometry atlas and device using the same {METHOD OF PIECEWISE LINEAR SCALING OF GEOMETRY ATLAS AND APPARATUS USING THE SAME}

The present invention relates to encoding and decoding of immersive video, and particularly to encoding and decoding of geometry atlases corresponding to depth information representing three-dimensional information in immersive video.

Recently, interest in realistic content has exploded and with the development of broadcasting equipment and video transmission technology, there is an increasing movement to actively utilize realistic content in various fields such as multimedia industries such as movies and TV.

Immersive video provides viewers with images from multiple viewpoints, allowing them to experience natural motion parallax, but has the disadvantage of having to store massive amounts of video data for multiple viewpoints.

In order to provide immersive video, a photographing device must capture images from multiple viewpoints and provide the captured images from multiple viewpoints. As the number of images from each shooting point increases, there is an advantage in being able to create high-quality 3D content, but problems with transmission bandwidth may arise because the corresponding number of images must be additionally sent during transmission. In addition, there is a disadvantage in that it requires a lot of storage space when there is a multi-view high-definition video.

Geometry information is depth information representing three-dimensional information in MPEG Immersive Video, and is generally expressed as a single-channel two-dimensional (2D) image.

Such geometry is expressed as a geometry atlas that removes redundancy between viewpoints in multi-view geometry.

Geometric images expressed as atlases are compressed through a 2D image codec.

The MPEG immersive video encoder encodes multi-view depth information by expressing it as atlases, and the MPEG immersive video decoder decodes geometry atlases and uses them to generate virtual viewpoint images through view synthesis.

In other words, geometry can be viewed as a two-dimensional image of depth or disparity information, and is simpler image information than a texture image. This geometry is used as 3D information when creating a virtual viewpoint image through rendering. In particular, geometry is of high importance at the boundary of an object, and geometry corresponding to the boundary of an object greatly affects rendering quality.

Ultimately, there is an urgent need for a new technology to efficiently encode/decode the geometry atlas while minimizing the increase in encoding data in MPEG immersive video.

The purpose of the present invention is to maximize the picture quality of immersive video while minimizing compression performance loss by expressing geometry based on importance.

Additionally, the purpose of the present invention is to maximize encoding/decoding efficiency of immersive video by expressing geometric information at different data representation accuracies (or different scales) according to importance in a plurality of areas.

Additionally, the purpose of the present invention is to express a geometry atlas with different data expression accuracies depending on importance in a plurality of areas, while minimizing syntax information that must be transmitted/received for this purpose.

A method of piecewise linear scaling of a geometric atlas according to the present invention for achieving the above object includes generating min-max normalized depth values; and generating geometry atlases by scaling the depth values corresponding to slopes of a plurality of linear sections.

At this time, the partially linear scaling method of the geometry atlas can be performed in an immersive video encoder.

At this time, the linear sections may be created by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the partial linear scaling method may further include generating an encoded immersive video signal using the geometry atlases.

At this time, the slopes may be determined based on sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set larger as the sample occurrence frequency increases.

At this time, the sample occurrence frequencies may be clipped to a preset range.

At this time, the linear sections include a first field (dq_interval_num) indicating the number of linear sections; and a second field (dq_norm_disp_pivot) indicating a scaled value corresponding to each of the linear sections.

At this time, the syntax fields may further include a third field (dq_scaled_disp_start) indicating a start depth value to which the partial linear scaling is applied.

In addition, the inverse scaling method of a geometric atlas according to an embodiment of the present invention includes the steps of restoring geometric atlases; and generating min-max normalized depth values by inversely scaling the geometry atlases corresponding to the slopes of a plurality of linear sections.

At this time, the inverse scaling method of the geometry atlas can be performed in an immersive video decoder.

At this time, the linear sections may be generated by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the inverse scaling method of the geometric atlas may further include generating a virtual viewpoint image using the min-max normalized depth values.

At this time, the slopes may be determined based on sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set so that more bits are allocated as the sample occurrence frequency increases.

At this time, the linear sections include a first field (dq_interval_num) indicating the number of linear sections; and a second field (dq_norm_disp_pivot) indicating a scaled value corresponding to each of the linear sections.

At this time, the syntax fields may further include a third field (dq_scaled_disp_start) indicating a start depth value to which the partial linear scaling is applied.

Additionally, an apparatus for partially linear scaling a geometry atlas according to an embodiment of the present invention includes a memory in which at least one program is recorded; and a processor executing the program. At this time, the program generates min-max normalized depth values; and instructions for performing a step of generating geometry atlases by scaling the depth values corresponding to slopes of a plurality of linear sections.

At this time, the linear sections may be created by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the slopes may be determined based on sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set larger as the sample occurrence frequency increases.

At this time, the linear sections include a first field (dq_interval_num) indicating the number of linear sections; and a second field (dq_norm_disp_pivot) indicating a scaled value corresponding to each of the linear sections.

According to the present invention, the image quality of immersive video can be maximized while minimizing compression performance loss by expressing geometry based on importance.

Additionally, the present invention can maximize encoding/decoding efficiency of immersive video by expressing geometric information at different data expression accuracies (or different scales) according to importance in a plurality of areas.

Additionally, the present invention can express a geometry atlas with different data expression accuracies depending on importance in a plurality of areas, while minimizing syntax information that must be transmitted/received for this purpose.

1 is a graph showing partial linear scaling of a geometric atlas according to an embodiment of the present invention.
Figure 2 is a block diagram showing an immersive video system according to an embodiment of the present invention.
FIG. 3 is a block diagram showing an example of the immersive video encoder shown in FIG. 2.
FIG. 4 is a block diagram showing an example of the immersive video decoder shown in FIG. 2.
Figure 5 is an operation flowchart showing a partially linear scaling method of a geometric atlas according to an embodiment of the present invention.
Figure 6 is an operation flowchart showing a method for inverse scaling of a geometric atlas according to an embodiment of the present invention.
Figure 7 is a block diagram showing the configuration of a computer system according to an embodiment of the present invention.

The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. The present embodiments only serve to ensure that the disclosure of the present invention is complete and that common knowledge in the technical field to which the present invention pertains is not limited. It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Although terms such as “first” or “second” are used to describe various components, these components are not limited by the above terms. The above terms may be used only to distinguish one component from another component. Accordingly, the first component mentioned below may also be the second component within the technical spirit of the present invention.

The terms used in this specification are for describing embodiments and are not intended to limit the invention. As used herein, singular forms also include plural forms, unless specifically stated otherwise in the context. As used in the specification, “comprises” or “comprising” implies that the mentioned component or step does not exclude the presence or addition of one or more other components or steps.

Unless otherwise defined, all terms used in this specification can be interpreted as meanings commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the drawings, identical or corresponding components will be assigned the same reference numerals and redundant description thereof will be omitted. .

Hereinafter, depth may be a concept including disparity. That is, in the following, all expressions expressed as depth or depth values can be replaced with disparity or disparity values.

1 is a graph showing partial linear scaling of a geometric atlas according to an embodiment of the present invention.

Referring to FIG. 1, it can be seen that min-max normalized depth values are scaled using a plurality of piecewise linear intervals.

Depending on the embodiment, the geometry atlas may generally have a 16-bit depth and may be generated in a downscaled format for 10-bit video coding.

At this time, min-max normalized depth values can be scaled to a range from {0,64} to {511, 1023}. That is, the min-max normalized depth values can be scaled to range from 0 to 511, or from 0 to 1023, or from 64 to 511, or from 64 to 1023.

In the generation of a geometry atlas, loss of depth information is incurred by this downscaling in the generation of geometry atlas. Furthermore, depth information loss may subsequently occur due to lossy coding of depth atlases. The partially linear scaling method of a geometry atlas according to an embodiment of the present invention can redistribute bits in the geometry codeword using partial linear scaling to reduce loss of depth information.

The specific process by which the depth atlas is created with min-max normalized values is described in “Test Model 7 for Immersive Video,” ISO/ It is described in detail in IEC JTC1/SC29/WG4, N0005.

The entire range of min-max normalized depth value is divided into a predetermined number of equal intervals. At this time, each interval is selectively scaled according to the frequency of the depth samples in the atlas. Specifically, depending on the frequency of occurrence of depth samples included in a specific section, the scaled depth range corresponding to the specific section may be adaptively determined.

In Figure 1, the original depth value of each interval is mapped to the corresponding scaled depth range. Then, geometric atlases are created as 10-bit depth representation.

Piecewise linear scaling can be defined as:

d' = (b2 _i - b1 _i ) / (a2 _i - a1 _i ) * (d - a1 _i ) + b1 _i

At this time, d is the depth value to be scaled, i is the interval index of the d value, and a1 _i and a2 _i are each on the original depth range. ) are the minimum and maximum depth of the ith section. At this time, b1 _i and b2 _i are the minimum and maximum depths of the ith section on the scaled depth range, respectively.

Inverse scaling may be required to perform rendering on the decoder side, and this may be performed in the reverse way of (forward) scaling.

To apply the proposed piecewise linear scaling, the number of linear intervals and the depth values of all scaled intervals can be signaled. As will be described later, this information can be signaled by setting the syntax element dq_quantization_law to 1.

In the example shown in FIG. 1, a case where there are 7 linear intervals is used as an example, but the technical idea of the present invention is not limited to this. For example, there may be 16 linear sections.

A piecewise linear scaling model can be derived on the encoder side. At this time, scaling of each section may be applied according to the importance in terms of the rendered view quality of the depth values in the section. For example, the piecewise linear scaling method according to one embodiment of the present invention further assigns codewords to depth intervals that have more frequent occurrence of depth. values). Furthermore, since depth information in areas surrounding an object tends to be important from the perspective of rendering view quality, the partial linear scaling method according to an embodiment of the present invention further allocates codewords to depth sections containing samples around the object. can do. At this time, the partial linear scaling method according to an embodiment of the present invention can be applied to both the basic view and additional views.

For example, the derivation of a piecewise linear model can be performed as follows.

Step 1) The original depth area is divided into N equal sections (intervals). (N is a natural number such as 7 or 16)

Step 2) Calculate the percentage of sample occurrence in each depth interval, and set the occurrence frequency to [1/32, Clipping is performed to a preset range such as [1/8].

Step 3) Adjust the interval range based on the statistics resulting from step 2.

Table 1 below is a table showing an example of fields signaled in relation to partial linear scaling of a geometry atlas according to an embodiment of the present invention.

depth_quantization(　viewID　) { Descriptor dq_quantization_law [ viewID ] u(8) if(　dq_quantization_law[　viewID　]　==　0　) { dq_norm_disp_low [ viewID ] fl(32) dq_norm_disp_high [ viewID ] fl(32) } else if(dq_quantization_law[ viewID ] == 1 ) { dq_norm_disp_low [ viewID ] fl(32) dq_norm_disp_high [ viewID ] fl(32) dq_num_piece_minus1 [viewID] u(8) dq_scaled_disp_start [viewID] for( i = 0; i <= dq_num_piece [ viewID]; i++ ) dq_scaled_disp_range [ viewID ] [ i ] fl(32) } if(　vme_embedded_occupancy_enabled_flag　) dq_depth_occ_threshold_default [ viewID ] ue(v) }

Referring to Table 1, in the syntax for signaling depth quantization, if the value of the syntax element of dq_quantization_law is set to 1, it can be seen that information for partial linear scaling is signaled. In this case, dq_quantization_law [ viewID ] indicates the type of depth quantization method of the view with the same view ID as viewID. At this time, if dq_quantization_law is 0, uniform quantization can be applied to depth values. At this time, if dq_quantization_law is 1, partial linear scaling of the geometry atlas according to an embodiment of the present invention can be applied.

At this time, dq_norm_disp_low [ viewID ] and dq_norm_disp_high [ viewID ] represent the minimum normalized depth value (min in Figure 1) and maximum normalized depth value (max in Figure 1) of the view having the same view ID as viewID, respectively. .

At this time, dq_num_piece_minus1[ viewID ] represents the number of linear intervals for partial linear scaling of a view with the same view ID as viewID minus 1. Alternatively, instead of dq_num_piece_minus1, the derived syntax may be encoded/decoded by subtracting a natural number of 2 or more from the number of linear sections. At this time, information for specifying the number of linear sections, such as the dq_num_piece_minun1 field, may correspond to the first field of the claim. Depending on the embodiment, the first field may be dq_num_piece, and in this case, dq_num_piece may directly represent the number of linear sections. Depending on the embodiment, the first field may be signaled based on information obtained by adding or subtracting various natural numbers from the number of linear sections for partial linear scaling, depending on the case.

At this time, dq_scaled_disp_start[ viewID ] represents the start depth value for partial linear scaling of the view with the same view ID as viewID. Depending on the embodiment, dq_scaled_disp_start [viewID] may not be signaled. If signaling of the dq_scaled_disp_start value is omitted, the start depth value for partial linear scaling can be inferred to be the same value as dq_norm_disp_low. By signaling dq_scaled_disp_start[ viewID ] separately from dq_norm_disp_low[ viewID ], the section to which partial linear scaling is applied can be set more freely. At this time, information indicating the start depth value for partial linear scaling, such as the dq_scaled_disp_start field, may correspond to the third field of the claim.

At this time, dq_scaled_disp_range[viewID][i] may indicate the range of the i-th linear section for partial linear scaling of the view having the same view ID as viewID. As an example, dq_scaled_disp_range[viewID][i] may represent the maximum value, minimum value, or difference between the maximum and minimum values of the scaled depth value within the i-th section. At this time, dq_scaled_disp_range[ viewID ][i] is defined in a for loop that is repeated as many times as the number of linear sections, and by signaling the upper limit of the scaled depth value for each linear section, sections of the scaled depth range can be displayed with minimal information. there is. As another example, for the first section (e.g., i is 0) or the last section (e.g., i is dq_num_piece_minus1+1), signaling of the above information dq_scaled_disp_range may be omitted. At this time, information indicating the range of the ith linear section, such as the dq_scaled_disp_range field, may correspond to the second field of the claim.

At this time, dq_num_piece, which is a variable used to set the conditions of the for loop in Table 1, may correspond to dq_num_piece_minus1+1.

Table 2 below is a table showing other examples of fields signaled in relation to partial linear scaling of a geometry atlas according to an embodiment of the present invention. Compared to the embodiment in Table 1, encoding/decoding of information indicating the starting depth value for partial linear scaling was excluded. In this case, the minimum value of the normalized depth value (i.e., dq_norm_disp_low) may be set to the depth minimum value at which partial linear scaling is performed.

else if　( dq_quantization_law[ viewID ] == 1 ) { dq_norm_disp_low [viewID] dq_norm_disp_high [viewID] dq_interval_num [viewID] for(i=0;i<= dq_interval_num [ viewID ];i++) dq_norm_disp_pivot [viewID][ i ] }

At this time, dq_quantization_law[ viewID ] indicates the type of depth quantization method of the view with the same view ID as viewID. At this time, if dq_quantization_law is 0, uniform quantization can be applied to depth values. At this time, if dq_quantization_law is 1, partial linear scaling of the geometry atlas according to an embodiment of the present invention can be applied. At this time, dq_norm_disp_low [ viewID ] and dq_norm_disp_high [ viewID ] are the minimum of the view having the same view ID as viewID, respectively. The normalized depth value (min in Figure 1) and the maximum normalized depth value (max in Figure 1) are shown.

At this time, dq_interval_num[viewID] represents the number of linear intervals for partial linear scaling of a view with the same view ID as viewID. At this time, the dq_interval_num field may correspond to the first field of the claim.

At this time, dq_norm_disp_pivot[ viewID ][i] represents the normalized depth or disparity value of the ith pivot or linear section in the partially linear scaled domain of the view having the same view ID as viewID. At this time, dq_norm_disp_pivot[viewID][i] may represent the scaled depth value (upper limit) of the ith linear section for partial linear scaling with the same view ID as viewID. At this time, dq_norm_disp_pivot [ viewID ][i] is defined in a for loop that is repeated as many times as the number of linear sections, and by signaling the upper limit of the scaled depth value for each linear section, sections of the scaled depth range can be displayed with minimal information. there is. At this time, the dq_norm_disp_pivot field may correspond to the second field of the claim. At this time, 1 minus the total number of dq_norm_disp_pivot[ viewID ][i] may be equal to dq_interval_num[ viewID ].

Figure 2 is a block diagram showing an immersive video system according to an embodiment of the present invention.

Referring to FIG. 2, an immersive video system according to an embodiment of the present invention includes an immersive video encoder 210 and an immersive video decoder 220.

At this time, the immersive video encoder 210 may be an MPEG immersive video encoder, and the immersive video decoder 220 may be an MPEG immersive video decoder.

The immersive video encoder 210 performs partial linear scaling of the geometric atlas. At this time, the immersive video encoder 210 generates min-max normalized depth values; and generating geometry atlases by scaling the depth values corresponding to the slopes of a plurality of linear sections.

The immersive video encoder 210 can perform various functions for encoding immersive video in addition to partially linear scaling of the geometry atlas.

The immersive video decoder 220 restores the immersive video by receiving the encoded immersive video and decoding it.

The immersive video decoder 220 can perform inverse scaling of the geometric atlas. At this time, the immersive video decoder 220 performs the following steps: restoring geometry atlases; and generating min-max normalized depth values by inversely scaling the geometry atlases according to the slopes of a plurality of linear sections.

In addition to inverse scaling of the geometric atlas, the immersive video decoder 220 can perform various functions for decoding immersive video and generating a virtual viewpoint image.

FIG. 3 is a block diagram showing an example of the immersive video encoder shown in FIG. 2.

Referring to FIG. 3, the immersive video encoder shown in FIG. 2 may include a partial linear scaling device 310 and an encoded immersive video generator 320.

The partial linear scaling device 310 generates min-max normalized depth values and scales the depth values corresponding to the slopes of a plurality of linear sections to create geometry atlases. can be created.

The encoded immersive video generator 320 performs various functions for encoding immersive video.

FIG. 4 is a block diagram showing an example of the immersive video decoder shown in FIG. 2.

Referring to FIG. 4, the immersive video decoder shown in FIG. 2 may include an inverse scaling device 410 and a viewpoint synthesizer 420.

The inverse scaling device 410 restores geometry atlases and inversely scales the geometry atlases according to the slopes of a plurality of linear sections to generate min-max normalized depth values.

The viewpoint synthesizer 420 generates a virtual view image through view synthesis.

Figure 5 is an operation flowchart showing a partially linear scaling method of a geometric atlas according to an embodiment of the present invention.

Referring to FIG. 5, the partially linear scaling method of the geometric atlas according to an embodiment of the present invention generates min-max normalized depth values (S510).

In addition, the partially linear scaling method of a geometric atlas according to an embodiment of the present invention generates geometry atlases by scaling the depth values corresponding to the slopes of a plurality of linear sections (S520).

At this time, the linear sections may be created by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the slopes may be determined based on the sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set larger as the sample occurrence frequency increases.

At this time, the sample occurrence frequencies may be clipped to a preset range.

At this time, the linear sections use syntax fields including a first field (dq_interval_num) indicating the number of linear sections and a second field (dq_norm_disp_pivot) indicating a scaled value corresponding to each of the linear sections. This can be signaled.

At this time, the syntax fields may further include a third field (dq_scaled_disp_start) indicating a start depth value to which the partial linear scaling is applied.

Each step shown in FIG. 5 can be performed in the immersive video encoder shown in FIG. 1.

Although not explicitly shown in FIG. 5, the method of partially linear scaling a geometric atlas according to an embodiment of the present invention may further include generating an encoded immersive video signal using the geometric atlases. .

Figure 6 is an operation flowchart showing a method for inverse scaling of a geometric atlas according to an embodiment of the present invention.

Referring to FIG. 6, the inverse scaling method of a geometric atlas according to an embodiment of the present invention restores the geometric atlases (S610).

In addition, the inverse scaling method of a geometric atlas according to an embodiment of the present invention generates min-max normalized depth values by inversely scaling the geometric atlases according to the slopes of a plurality of linear sections. (S620).

At this time, the linear sections may be generated by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the slopes may be determined based on sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set so that more bits are allocated as the sample occurrence frequency increases.

At this time, the linear sections use syntax fields including a first field (dq_interval_num) indicating the number of linear sections and a second field (dq_norm_disp_pivot) indicating a scaled value corresponding to each of the linear sections. This can be signaled.

At this time, the syntax fields may further include a third field (dq_scaled_disp_start) indicating a start depth value to which the partial linear scaling is applied.

Each step shown in FIG. 6 can be performed in the immersive video decoder shown in FIG. 1.

Although not explicitly shown in FIG. 6, the inverse scaling method of the geometric atlas according to an embodiment of the present invention generates a virtual viewpoint image using the min-max normalized depth values. Additional steps may be included.

Figure 7 is a block diagram showing the configuration of a computer system according to an embodiment of the present invention.

The partially linear scaling device of the geometric atlas, the inverse scaling device of the geometric atlas, the encoded immersive video generator, the viewpoint synthesizer, the immersive video encoder, and the immersive video decoder according to the embodiment are computer-readable recording media. It may be implemented in system 700.

Computer system 700 may include one or more processors 710, memory 730, user interface input device 740, user interface output device 750, and storage 760 that communicate with each other via bus 720. You can. Additionally, the computer system 700 may further include a network interface 770 connected to the network 780. The processor 710 may be a central processing unit or a semiconductor device that executes programs or processing instructions stored in the memory 730 or storage 760. The memory 730 and storage 760 may be storage media including at least one of volatile media, non-volatile media, removable media, non-removable media, communication media, and information transfer media. For example, memory 730 may include ROM 731 or RAM 732.

At this time, at least one program may be recorded in the memory 730.

At this time, the processor 710 can execute the program. At this time, the program generates min-max normalized depth values; and instructions for generating geometry atlases by scaling the depth values corresponding to slopes of a plurality of linear sections.

At this time, the linear sections may be generated by dividing the entire area (entire range) corresponding to the minimum-maximum normalized depth values into equal intervals.

At this time, the slopes may be determined based on sample occurrence frequencies of the linear sections.

At this time, each of the slopes can be set larger as the sample occurrence frequency increases.

At this time, the linear sections include a first field indicating the number of linear sections; and a second field indicating a scaled value corresponding to each of the linear sections.

According to another embodiment of the present invention, the partial linear scaling method of a geometric atlas, the loss of depth information is minimized, thereby ensuring the efficiency of view synthesis. The partially linear scaling method of a geometric atlas according to an embodiment of the present invention can generate a partially linear scaling model based on the occurrence frequency of depth values in an additional view.

As described above, the partial linear scaling method of a geometric atlas, the inverse scaling method, and the apparatus therefor according to the present invention are not limited to the configuration and method of the embodiments described above, and the embodiments can be applied in various ways. All or part of each embodiment may be selectively combined so that modifications can be made.

210: Immersive video encoder
220: Immersive video decoder

Claims (20)

In the piecewise linear scaling method of a geometric atlas performed in an immersive video encoder,
generating min-max normalized depth values; and
Generating geometry atlases by scaling the depth values corresponding to slopes of a plurality of linear sections,
The depth values correspond to the depth values of immersive video,
The linear sections correspond to changes in the geometric atlases according to changes in the depth values,
The slopes are
A method of fractional linear scaling, determined based on sample occurrence frequencies of the linear sections. In claim 1,
The linear sections are
A partial linear scaling method, wherein the entire area (entire range) corresponding to the min-max normalized depth values is divided into equal intervals. In claim 1,
The partial linear scaling method is
A method for fractional linear scaling, further comprising generating an encoded immersive video signal using the geometry atlases. delete In claim 1,
Each of the above slopes is
A piecewise linear scaling method that is set larger as the frequency of sample occurrence increases. In claim 1,
A partial linear scaling method in which the sample occurrence frequencies are clipped to a preset range. In claim 1,
The linear sections are
a first field indicating the number of linear sections; and
A partial linear scaling method signaled using syntax fields including a second field indicating a scaled value corresponding to each of the linear intervals. In claim 7,
The syntax fields are
Partially linear scaling method further comprising a third field indicating a starting depth value to which the scaling is applied. In the inverse scaling method of a geometric atlas performed in an immersive video decoder,
Restoring geometry atlases; and
Inversely scaling the geometry atlases corresponding to the slopes of a plurality of linear sections to generate min-max normalized depth values,
The depth values correspond to the depth values of immersive video,
The linear sections correspond to changes in the geometric atlases according to changes in the depth values,
The slopes are
A method for inverse scaling of a geometric atlas, determined based on sample occurrence frequencies of the linear sections. In claim 9,
The linear sections are
A method for inverse scaling of a geometric atlas, wherein the entire area (entire range) corresponding to the min-max normalized depth values is divided into equal intervals. In claim 9,
The inverse scaling method of the geometry atlas is
Inverse scaling method of a geometry atlas, further comprising generating a virtual viewpoint image using the min-max normalized depth values. delete In claim 9,
Each of the above slopes is
A method of inverse scaling of geometric atlases, where the more frequently a sample occurs, the more bits are assigned. In claim 9,
The linear sections are
a first field indicating the number of linear sections; and
A method for inverse scaling of a geometry atlas, signaled using syntax fields including a second field indicating a scaled value corresponding to each of the linear sections. In claim 14,
The syntax fields are
A method for inverse scaling of a geometric atlas, further comprising a third field indicating a starting depth value to which the scaling is applied. a memory in which at least one program is recorded; and
Includes a processor that executes the program,
The above program is,
generating min-max normalized depth values; and
Includes instructions for performing a step of generating geometry atlases by scaling the depth values corresponding to the slopes of a plurality of linear sections,
The depth values correspond to the depth values of immersive video,
The linear sections correspond to changes in the geometric atlases according to changes in the depth values,
The slopes are
Fractionally linear scaling device, determined based on sample occurrence frequencies of the linear sections. In claim 16,
The linear sections are
Partially linear scaling device, wherein the entire area corresponding to the min-max normalized depth values is divided into equal intervals. delete In claim 16,
Each of the above slopes is
A piecewise linear scaling device that is set larger the more frequently the sample occurs. In claim 16,
The linear sections are
a first field indicating the number of linear sections; and
Partially linear scaling device, signaled using syntax fields including a second field indicating a scaled value corresponding to each of the linear intervals.

Images