JP2001078184A - Extraction area encoding method, decoding method, encoder, decoder, extraction area encoding program, and recording medium recording decoding program - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To increase the coding efficiency in coding an extraction area. SOLUTION: A uniform color area C adjacent to the uniform color area A is detected. The shape contours of the uniform color areas A and C are divided at both ends of the overlapping portion of the shape contours,
Labels A1, A2, C1, and C2 are respectively attached. A divided configuration table is generated in which the contour line of the uniform color area A is composed of A1 and A2 and the contour lines C1 and A2 of the uniform color area C, and is encoded and decoded together with each divided contour line. Send to the side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for separating an original image into a uniform color area, a line image and a texture area and extracting the shape of the extracted uniform color area as a contour of the extracted uniform color area. The present invention relates to an extraction region encoding method and a decoding method for encoding using a contour line around a color region, and an extraction region encoder and a decoder.

[0002]

2. Description of the Related Art A technique of dividing an image into objects and performing communication and encoding is used in MPEG-4 and the like.

One method of decomposing a line image into a uniform color region, a line image, and a texture region and coding the same is disclosed in Japanese Patent Application No. 11-110,086.
No. 47651 (Furukaku, Watanabe: "Image coding method, decoding method, coding apparatus, decoding apparatus, and storage medium storing those methods").

[0004]

In the conventional method described in the above-mentioned patent application, when encoding a shape contour, one shape contour is encoded for one uniform color area. When adjacent uniform color regions are in contact with each other as shown in FIG. 14A, the shape contour of each uniform color region is encoded as shown in FIG. FIG. 14B is a diagram in which the positions of the uniform color areas A and B are shifted to emphasize the shape contour.

In this conventional method, the outline of the thick line portion in FIG. 14 (3) is coded in both the uniform color areas A and B, and there is a problem that the coding efficiency is deteriorated.

An object of the present invention is to provide an extraction area encoding method and decoding method for efficiently encoding an extraction area, an extraction area encoder, a decoder, an extraction area encoding program, and a recording medium on which a decoding program is recorded. To provide.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to a case where a part of the contours of the uniform color areas adjacent to each other is located at the same position. Then, each shape contour is divided at both ends of a portion located at the same position, and one of the divided shape contours located at the same position is replaced with the other divided shape contour. At this time, the label of the replaced divided contour line is also written in the divided constitution table indicating which divided contour line is formed by the contour line of each uniform color area. This allows
The overlapping part of the shape contour line having the part overlapping with the adjacent uniform color area does not need to be encoded in each uniform color area, and the encoding efficiency is improved.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings.

Referring to FIG. 1, an extraction area encoder according to an embodiment of the present invention includes a uniform color area extraction section 2, a uniform color area labeling section 4, a color information extraction section 6, and a shape contour line generation section 8.
It comprises a shape contour dividing unit 10, a division configuration table creating unit 13, a color information encoding unit 15, a division shape outline encoding unit 16, a division configuration table encoding unit 17, and a combining unit 21.

[0010] From the input image 1, a uniform color region extraction unit 2 extracts a uniform color region 3. The uniform color region 3 is labeled by the uniform color region labeling section 4 to become a uniform color region 5 with region numbers. As a method of labeling the uniform color regions, numbers and alphabets are assigned in the order of extracting the uniform color regions, the area order of the uniform color regions, and the like. The uniform color area 5 with the area number labeled by the uniform color area labeling section 4 includes a color information extracting section 6 and a shape outline generating section 8.
Sent to The color information extraction unit 6 extracts a representative color of the uniform color area, and adds the representative color to the color information 7 together with the area number of the extracted area.
And sends it to the color information encoding unit 15. In addition, the shape outline generation unit 8 generates a shape outline 9 around the region numbered uniform color area 5 and divides the shape outline 9 into the shape outline division unit 1.
Send to 0. The shape contour dividing unit 10 divides the input shape contour and sends the divided shape contour 11 to the divided shape contour encoding unit 16. In addition, the shape contour dividing unit 10 sends information on how the shape contour is divided as the shape contour dividing data 12 to the divided constitution table generating unit 13. The division configuration table generation unit 13 creates a division configuration table 14 that describes which shape outline is composed of which division shape outline with reference to the configuration outline division configuration data 12, and generates a division configuration table code. To the conversion unit 17. The color information encoding unit 15, the division shape outline encoding unit 16, and the division configuration table encoding unit 17 encode the color information 7, the division shape outline 11, and the division configuration table 14, respectively. The synthesizing unit 21 includes the coded color information 18, the coded divided outline 19, and the coded divided configuration table output from the color information encoding unit 15, the divided shape outline encoding unit 16, and the divided configuration table encoding unit 17, respectively. 20 are synthesized and output as synthesized encoded data 22.

A conventional same-color region extraction method for extracting a characteristic portion of an image in the uniform-color region extraction section 2 is described in “Image Analysis Handbook”, published by the University of Tokyo, edited by Mikio Takagi and Yoshihisa Shimoda. 689 Part II Chapter 2 There is a simple area expansion method in area division and the like. The processing flow of the simple area extension method is shown below.

(1) An image is raster-scanned to search for a pixel that does not belong to any area.

(2) The gray level of the pixel is compared with the gray level of a pixel that does not yet belong to any area in the vicinity (4-connected or 8-connected), and a threshold θ
If it is below, it is integrated as one area and a label is added.

(3) The above-mentioned operation (2) is performed while paying attention to the newly integrated pixels.

(4) The above operations (2) and (3) are repeated until the area can no longer be expanded.

(5) Returning to (1) above, search for a new pixel and repeat the process.

Referring to FIG. 2, an extraction area decoder according to an embodiment of the present invention includes a separation section 31, a color information decoding section 35, a divided shape outline decoding section 36, a divided configuration table decoding section 37, and a shape outline synthesis. It comprises a unit 41 and a uniform color area generation unit 43.

The separating section 31 separates the composite coded data 22 received from the extraction area coder into coding color information 32, a coding division contour 33, and a coding division configuration table 34.
The coded color information 32, the coded division outline 33, and the coded division configuration table 34 are respectively decoded by a color information decoding unit 35, a separated shape outline decoding unit 36, and a division configuration table decoding unit 37 to decode color information 38, decoding The divided shape contour 39 is decoded into the decoded divided configuration table 40. The shape contour synthesizing unit 41 refers to the decoding division configuration table 40 and synthesizes the composite shape outline 42 using the decoded division shape outline 39. The uniform color area generation unit 43
The composite shape contour 42 and the area surrounded by the composite shape contour are colored with the color indicated by the decoded color information 38 and output as an output image 44.

Next, the operation of this embodiment will be described with a specific example.
Shape contour line division and shape contour line division configuration data 12
Will be described with reference to the flowchart of FIG.

As shown in FIG. 4, the uniform color region 5 labeled A to E by the uniform color region labeling section 4 will be described.

In the present embodiment, raster scanning is performed from the upper left of FIG. 4, and the first uniform color area found is labeled A, and the next uniform color area found is labeled B to A to E in this order. . The shape outline 9 is generated by the shape outline generation unit 8 from the uniform color area in FIG. The shape contour line in FIG. 4 is a solid line around each uniform color area as shown in FIG. The shape contour line 9 in FIG. 5 is divided into divided shape contour lines 11 by the shape contour line dividing unit 10 as follows. Although the actual processing is performed only on the shape contour line 9, a uniform color area is also shown in the same figure for the sake of explanation.

First, in order to perform on the uniform color area A,
The area number N is initialized (step 101). Next, a uniform color area adjacent to the uniform color area A is detected (step 103). In the present embodiment, the uniform color area C is adjacent to the uniform color area A (FIG. 6). FIG. 7A shows only the uniform color regions A and C which are slightly shifted in position.
The thick line and the dotted line in FIG. A thick line portion where an adjacent shape contour is overlapped is detected (step 104). Next, as shown in FIG. 7B, the shape contour 9 is divided at both ends of the thick line, and A1 and A
Labels 2, 2, C1 and C2 (step 105).
The shape contour of the uniform color area A is composed of A1 and A2 (A: = A1 + A2), and the shape contour of the uniform color area C is
Information composed of C1 and C2 (C: C1 + C2) is created and stored as the shape / contour division data 12 (step 106). Here, since A2 and C2 are the divided contours at the same position, the divided contour of A2 is used instead of C2 (step 107). Then, as shown in FIG. 7 (3), the shape contour line division configuration data 12 is stored using A2 instead of C2 (C: = C1 +
A2) (Step 108), the divided contour line C2 is deleted.

Next, the area number N is incremented by 1 to add a uniform color area B
Then, the shape contour is divided (step 109).
Then, similarly to the uniform color area A, a uniform color area adjacent to the uniform color area B is detected. In the present embodiment, the uniform color area C and the uniform color area E are adjacent to the uniform color area B (FIG. 8). Similar to the uniform color area A, the uniform color areas B, C,
FIG. 9 shows a case where only E is taken out and the position is slightly shifted.
And the bold line and the dotted line in FIG. 9 are the shape contour lines. The bold line portions are where the adjacent shape contour lines overlap.

Next, as shown in FIG. 10A, the shape contour is divided at both ends of the thick line, and B1, B2, B3,
Label C1, C3, A2 (C2), E1, E2. Then, as shape contour line division configuration data 12,
B: = B1 + B2 + B3, C: = C1 + C3 + A2,
E: = E1 + E2 is created and stored. Here, since B2 and C3 and B3 and B2 are divided shape contours located at the same position, as shown in FIG. 10 (2), B2 and B3 are used instead of C3 and E2 to form shape contour line division configuration data. 12 (C: = C1 + B2 + A2, E: = E1 + B3),
The divided shape contour lines C3 and E2 are deleted.

The same processing is performed until N becomes equal to the number (Num) of the extracted uniform color areas (step 102).
In the present embodiment, FIG. 11 shows that the same processing is performed on the uniform color regions C, D, and E to divide the shape outline. At this time, the divided contour lines A1, A2, B1, B2,
B3, C1, D1, D2, and E1 are sent to the divided shape contour encoding unit 16. At this time, the shape / contour division configuration data 12 is A: = A1 + A2, B: = B1 + B2 +
B3, C: = C1 + B2 + A2, D: = D1 + D2 + C
1, E: = E1 + B3 + D2, which is sent to the division configuration table creating unit 13 and the division configuration table 14 is created.

The color information encoding unit 15, the division shape contour encoding unit 16, and the division configuration table encoding unit 17 encode the color information 7, the division shape outline 11, and the division configuration table 14, respectively.
The coded color information 18, the coded division outline 19, and the coded division configuration table 20 are output to the combining unit 21. Synthesis unit 21
Synthesizes the coded color information 18, the coded division outline 19, and the coded division configuration table 20, and outputs the synthesized coded data 22.

In the decoder, the input composite coded data 2
2 is separated by a separation unit 31 into coding color information 32, coding division outline 33, and coding division configuration table 34. Encoding color information 32, encoding division outline 33, encoding division configuration table 34
Are decoded into a decoded color information 38, a decoded divided shape outline 39, and a decoded divided configuration table 40 by a color information decoding unit 35, a separated shape outline decoding unit 36, and a divided configuration table decoding unit 37, respectively. The shape contour synthesizing unit 41 refers to the decoding division configuration table 40 and synthesizes the composite shape outline 42 using the decoded division shape outline 39. FIG. 12 shows a composite shape outline 42 created using the decoding division configuration table 40 and the decoding division shape outline 39. The uniform color area generation unit 43 outputs the decoded color information 3
8, the composite shape contour 42 and the contour 42
The area surrounded by is colored with the color indicated by the decoding color information 38 and output as an output image 44.

In the uniform color area generating section 43, only the composite shape outline 42 may be colored.

FIGS. 13A and 13B are block diagrams of an extraction area encoder and a decoder according to another embodiment of the present invention, respectively, which embody the present invention on a computer such as a personal computer.

The extraction area encoder includes an input device 51 for inputting an image 1 and a storage device 5 as a hard disk.
2, a transmission device 53 for transmitting the combined coded data 22 to the extraction area decoder, and each unit 2, 4, 6,
A floppy disk on which an extraction area code program including the processing of 8, 10, 13, 15 to 17, and 21 is recorded;
It comprises a recording medium 54 such as a CD-ROM or a magneto-optical disk, and a data processing device (CPU) 55 which reads an extraction area encoding program from the recording medium 54 and executes the program.

The extraction area decoder outputs the synthesized encoded data 22
, A storage device 62 that is a hard disk, an output device 63 such as a display or a printer that outputs the output image 44, and the respective units 31, 35 to 35 in FIG.
It comprises a recording medium 64 in which an extraction area decoding program composed of the components 37, 41 and 43 is recorded, and a data processing device (CPU) 65 which reads the extraction area decoding program from the recording medium 64 and executes the program.

[0032]

As described above, according to the present invention, it is possible to efficiently encode an extraction area without encoding a shape contour line twice between adjacent uniform color areas.

[Brief description of the drawings]

FIG. 1 is a block diagram of an extraction area encoder according to an embodiment of the present invention.

FIG. 2 is a block diagram of an extraction area decoder according to one embodiment of the present invention.

FIG. 3 is a flowchart of a shape contour line division and a shape contour line division configuration data creation algorithm.

FIG. 4 is a diagram showing uniform color regions labeled AE.

FIG. 5 is a diagram showing shape contour lines of uniform color areas A to E in FIG. 4;

FIG. 6 is a diagram showing that a uniform color area A is adjacent to a uniform color area C;

FIG. 7 shifts a portion where the shape contours of the uniform color areas A and C overlap (FIG. 7 (1)), divides the shape contour at both ends of the overlapping portion, and labels each of them (FIG. 7).
(2)), instead of the label C2 of the overlapping part, A
FIG. 7 is a diagram showing that No. 2 is used (FIG. 7 (3)).

FIG. 8 is a diagram showing that uniform color regions C and E are adjacent to uniform color region B;

9 is a diagram showing only uniform color regions B, C, and E extracted from FIG. 8 and shifted in position.

FIG. 10 is a diagram in which the shape contours of the uniform color regions B, C, and E are divided at both ends of an overlapping portion, and labels are attached to the divided shape contours (FIG. 10 (1)); FIG. 9 is a diagram showing that divided shape outlines B2 and B3 of the uniform color region B are used instead of labels C3 and E2 of the divided shape outlines of the uniform color regions C and E, respectively.

FIG. 11 shows uniform color areas A, B, C, D, and E shown in FIG.
FIG. 4 is a diagram showing divided shape contour lines and labels attached thereto.

FIG. 12 is a diagram illustrating a composite shape contour created using a division configuration table and a divided shape contour in a decoder.

FIG. 13 is a block diagram illustrating an extraction region encoder and a decoder according to another embodiment of the present invention.

FIG. 14 is a diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input image 2 Uniform color area extraction part 3 Extraction uniform color area 4 Uniform color area labeling part 5 Uniform color area with area number 6 Color information extraction part 7 Color information 8 Shape outline generation part 9 Shape outline 10 Shape outline Division unit 11 Divided shape contour line 12 Shape contour line division configuration data 13 Division configuration table creation unit 14 Division configuration table 15 Color information encoding unit 16 Division shape contour encoding unit 17 Division configuration table encoding unit 18 Encoded color information DESCRIPTION OF SYMBOLS 19 Encoding division | segmentation line 20 Encoding division | segmentation structure table 21 Synthesizing part 22 Synthetic encoding data 31 Separation part 32 Encoding color information 33 Encoding division | segmentation line 34 Encoding division | segmentation structure table 35 Color information decoding part 36 Division shape outline Decoding unit 37 Division configuration table decoding unit 38 Decoding color information 39 Decoding division outline 40 Decoding division configuration table 41 Shape outline synthesis unit 42 Synthetic shape outline 43 Uniform color area Generator 44 output image 101-109 Step 51 input device 52, 62 memory 53 transmission device 54, 64 recording medium 55, 65 the data processor 61 receiving apparatus 63 output device

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) 9A001 F term (Reference) 5B057 CA01 CA16 CB01 CB18 CG07 DA08 DC16 DC25 5C057 AA03 AA06 EA01 ED10 EL01 EM07 GH03 GH05 5C059 MA00 MB19 MB03 MB03 MB PP14 PP22 PP28 RC14 SS06 SS20 UA02 UA05 5C078 AA09 BA21 BA66 5L096 AA02 EA24 FA06 FA15 GA34 9A001 EE04 HH23 HH25 HH27

Claims (7)

[Claims] 1. An original image is decomposed into a uniform color area, a line image, and a texture area, and the shape of the extracted uniform color area is referred to as a contour of the extracted uniform color area. In an extraction area encoding method for encoding using a line, a representative color of the extracted uniform color area is extracted as color information, encoded, the shape outline is divided into a plurality of shapes, and a label is assigned to each of the divided shape outlines. To generate a divided configuration table indicating which of the divided contour lines the contour lines of each extracted uniform color region are composed of, and individually generate the divided constitution table and each of the divided contour lines. A method for encoding an extraction area, comprising encoding and transmitting the encoded division shape contour and the encoding division configuration table together with encoding color information. 2. Each of the contours of an extracted uniform color region which are adjacent to each other and in which a part of the contours overlaps is divided at both ends of the overlapping contours, and an encoding and division configuration table is obtained. When creating, use one of the divided shape contours for overlapping divided shape contours,
The extraction area encoding method according to claim 1. 3. The decoding method according to claim 1, further comprising receiving and decoding the coded color information, the coded divided shape contour and the coded divided configuration table, and decoding the divided configuration table. , An extracted region decoding method for reconstructing a divided shape contour line, coloring with reference to the color information, and outputting. 4. A uniform color area extracting means for inputting an original image and extracting a uniform color area; a uniform color area labeling means for labeling the extracted uniform color area; and a representative of each labeled uniform color area. Color information extracting means for extracting a color and outputting it as color information; shape contour extracting means for generating a shape contour line around each labeled uniform color area; and inputting each of the shape contour lines to obtain the uniform color. Shape contour line dividing means for detecting uniform color regions adjacent to the region, detecting overlapping portions in the shape contour lines of these uniform color regions, and dividing each shape contour line at both ends of the overlapping portion; A label is attached to each of the divided shape contour lines, and the shape contour line of each uniform color region that the shape contour line of each uniform color region is composed of divided shape contour lines and the divided shape contour lines that constitute it Label relationships Means for creating the described divided composition table, wherein the labels of the overlapping parts use the label of one of the parts, and color information for encoding the color information and outputting it as encoded color information Encoding means, encoding the divided shape contours, and encoding one of the divided shape contours overlapping with each other in the uniform color region adjacent to each other, as a coded divided shape contour; Division shape contour encoding means for outputting, the division configuration table encoding means for encoding the division configuration table and outputting it as an encoded division configuration table, the encoding color information, the encoding division shape contour, An extraction area encoder having a combining unit that combines an encoding division configuration table and outputs the resultant as combined encoded data. 5. An extraction area decoder corresponding to the extraction area encoder according to claim 4, wherein the synthesized coded data output from the synthesizing means is encoded color information, an encoded divided shape contour line. Separating means for separating into a coding division configuration table; color information decoding means for decoding the coding color information and outputting decoded color information; decoding the coding division shape contour; And a division configuration table decoding unit that decodes the encoded division configuration table and outputs a decoded division configuration table. The decoding configuration contour line is referred to by referring to the decoding division configuration table. And a shape contour synthesizing means for synthesizing the divided shape outlines and outputting a synthesized shape outline, and a uniform color area for coloring the synthesized shape outline with a color indicated by the decoded color information and outputting as an output image. Extraction area restoration with generation means No. 6. A uniform color region extracting process for inputting an original image and extracting a uniform color region; a uniform color region labeling process for labeling the extracted uniform color region; and a representative of each labeled uniform color region. A color information extraction process for extracting a color and outputting it as color information; a shape outline extraction process for generating a shape outline around each labeled uniform color region; A shape contour line dividing process for detecting uniform color regions adjacent to the region, detecting overlapping portions in the shape contour lines of these uniform color regions, and dividing each shape contour line at both ends of the overlapping portion; A label is attached to each of the divided shape contour lines, and the shape contour line of each uniform color region that the shape contour line of each uniform color region is composed of divided shape contour lines and the divided shape contour lines that constitute it Label relationships Creating a described divided composition table, in which a label of an overlapping part uses a label of either one of the divided composition table creation processing, and color information for encoding the color information and outputting it as encoded color information Encoding processing, encoding the divided shape contour lines, and overlapping one another of the uniform color regions adjacent to each other, for the divided shape contour lines, encodes only one shape contour line, as an encoded divided shape contour line A division shape contour encoding process to be output; a division configuration table encoding process that encodes the division configuration table and outputs it as an encoded division configuration table; the encoding color information, the encoding division shape outline, A recording medium on which an extraction area encoding program for causing a computer to execute a synthesizing process of synthesizing an encoding division configuration table and outputting as synthesized encoded data is recorded. 7. An extraction area decoding program corresponding to the extraction area encoding program according to claim 6, wherein the synthesized coded data output from the synthesis processing is coded color information, an encoded divided shape contour line. Separation processing for dividing into an encoding division configuration table; color information decoding processing for decoding the encoding color information and outputting decoded color information; decoding the encoding division shape contour; , A divided configuration contour decoding process for outputting the decoded divided configuration table, and a decoded configuration table decoding process for decoding the encoded divided configuration table and outputting a decoded divided configuration table. A contour shape synthesizing process for synthesizing a divided shape contour line using the above, and outputting a synthesized shape contour line; and a uniform color area for coloring the synthesized shape contour line with a color indicated by the decoded color information and outputting as an output image. Generation process A recording medium that stores an extraction area decoding program to be executed by a computer.