JP2857260B2 - Judgment method of rectangular area - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for determining an area in the field of image processing, and more particularly to a rectangular area effective for processing mixed images composed of a plurality of images having different properties for each property. And a method for determining an image area by using

[0002]

2. Description of the Related Art In recent years, in the field of image processing by a computer, with the development of image data input / output devices and storage devices, a large number of images including high-quality images have been developed by expanding the functions of DTP and in-house printing systems. Data handling has been required. Particularly, in the case of outputting a mixed image in which a plurality of images having different properties are mixed, the processing of image data tends to become more and more complicated. For example,
With the advent of high-density recording devices such as laser printers and plotters, it has become possible to output high-quality images containing both photographic images (dot images) and articles (linework information). Processing has become necessary. Such compression processing of mixed images requires parameters corresponding to each type of halftone dot and line drawing, and this has necessitated image area determination processing.

Conventionally, the following two methods have been used to determine each image area as described above. (1) Information called line control information is added to each line of the entire image, and the image type within one line is determined. (2) Various images are designated by a rectangular area, and a mixed image is expressed by a start point, an end point, and a type of the rectangular area. FIG. 5 shows line control information for explaining the method (1). In FIG. 5, reference numeral 100 denotes different types of images A,
4 shows a screen including B, C, D, and E. This screen 100 is represented by lines scanned at equal intervals in the horizontal direction.
In the figure, L1, L2, and L3 show examples of lines.

[0004] Line control information is added to each line. The line control information is information expressing what image (where from what dot to what dot) is an image in the target line. For example, the line control information of the line L2 is that the dots B0 to B3 are the image A, the dots B3 to B4 are the image C, the dots B4 to B5 are the image A, the dots B5 to B6 are the image E, and the dots B6 to BM are the image A. Indicates something. The method (1) can be most easily realized in hardware creation. Therefore, processing for each line can be performed at high speed. However, when the number of images in one line increases, the data amount increases, and when the total number of lines increases, the data amount increases. That is, as the image quality increases, the data amount increases.

FIG. 6 shows rectangular area information for explaining the method (2). 6, reference numeral 100 denotes the same screen as in FIG. The area of each image A, B, C, D, E is
It is described by the coordinate values of the upper left corner and lower right corner of each of the circumscribed rectangles 1, 2, 3, 4, and 5 of those images and the type of the image. For example, the image B is represented by the coordinates (X1, Y1) of the point 2-1 at the upper left corner of the circumscribed rectangle 2 and the coordinates (X2, Y4) of the point 2-2 at the lower right corner. In this method, the data amount of information depends only on the number of rectangular areas. Therefore, the data amount can be minimized. However, hardware for realizing the relationship between the control information of each line and the description of each rectangular area becomes complicated. Therefore, it takes time to determine the image area, and the overall processing speed cannot be increased.

[0006]

As described above, in order to compress and output a mixed image in which a plurality of types of images are mixed, logic for discriminating each image in each line and hardware for realizing the same are provided. is necessary. The method of determining an image by line control information for each line is simple in hardware and can perform high-speed processing, but has a large data amount. The method of representing each image by a rectangular area requires a small amount of data, but the hardware is complicated and not suitable for high-speed processing. As the handling of high-quality mixed images has increased, there has been a growing demand for a method for determining an image area that requires a smaller amount of data and that can be processed at high speed. SUMMARY An advantage of some aspects of the invention is to provide a rectangular area determination method which has a small data amount and can perform high-speed processing.

[0007]

Rectangular area determination method according to the invention According to an aspect of the image processing for representing a screen in which a plurality of types of images are mixed by a horizontal scanning line, a rectangle of each image
The initial rectangular area information that defines the area is stored in the upper left corner of the rectangular area.
By rearranging them in the order of the size of the Y coordinate of the starting point of
Create rectangular area information and follow the order of the new rectangular area information
Along the top and bottom sides of the rectangular area of each image on the screen.
The rectangular area of each image by the dividing line
Divided into multiple parts in the direction
Generate a differentiated rectangular area and start and end points of each subdivided rectangular area
By describing each coordinate and the type of image,
Complete subdivided rectangular area information that defines the segmented rectangular area
And a plurality of scan lines between the divided line adjacent is configured to be the line controlled by the same subdivision rectangular area information.

[0008]

First, rectangular areas of various images on one screen are defined by their circumscribed rectangles. Initial rectangular area information including the X and Y coordinates of the start point of the upper left corner and the end point of the lower right corner of each rectangular area and the type of image is stored in the memory. Next, the initial rectangular area information is set to the starting point Y of the rectangular area.
New rectangular area information rearranged in the order of the coordinates is created and stored in the memory. Next, in accordance with the order of the new rectangular area information, each rectangular area is divided by a horizontal dividing line passing through the start point and the end point of another rectangular area, and a subdivided rectangular area is generated. The coordinates of the start point and end point of each subdivided rectangular area can be easily obtained from the initial rectangular area information. In this way, the subdivided rectangular area information including the start point, the end point, and the type of image is completed and stored in the memory. When outputting an image, a plurality of lines between adjacent division lines are controlled by the same subdivided rectangular area information.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 illustrates the principle of the present invention. FIG.
In the figure, reference numeral 100 denotes a mixed image similar to that of FIG. 6, numbers in parentheses indicate types of images, and alphabetic characters in parentheses indicate a set of a plurality of lines (referred to as a line group) that can be described by the same information. Each of the images B, C, and C shown in FIG.
Each of the rectangular areas 2, 3, 4, and 5 of D and E is separated by a dividing line that passes along the upper side and the lower side of the other rectangular area, respectively, and some new subdivided rectangular areas are generated. Is done. Like the original rectangular area, the newly generated rectangular area is described by the (X, Y) coordinates of the start point (upper left corner) and the end point (lower right corner), and the type of image. As is apparent from FIG. 1, a plurality of lines (that is, a group of lines) between adjacent division lines have common line control information. In other words, the present invention is a description method having an intermediate property between the method of adding line control information for each line in the related art and the method of expressing each image by a rectangular area. Therefore, they have both advantages.

FIG. 2 shows the configuration of the present invention. The rectangular area information of the subdivided rectangular area is created in the following procedure. (1) The rectangular area information sorting unit 11 rearranges the initial rectangular area information stored in the initial rectangular area information storage unit 10 in order from the top of the Y coordinate of the start point (upper left corner) of each rectangular area. (2) The new rectangular area information obtained by the rearrangement in (1) is stored in the new rectangular area information storage unit 12. (3) Based on the new rectangular area information stored in the new rectangular area information storage section 12, the rectangular area subdividing section 13 subdivides the initial rectangular areas in the order in which the starting points have occurred. (4) For each subdivided rectangular area newly generated by subdivision, rectangular area information including a start point, an end point, and an image type is created and stored in the subdivided rectangular area information storage unit 14. (5) The above (1) to (4) are repeated until the processing is completed for all the initial rectangular areas.

FIG. 3 is a block diagram of each part 10, 11, 12, 1 of FIG.
Details of 3 and 14 are shown. Initial rectangular area information storage unit 1
0 stores start point information 10a including X and Y coordinates of the start point of each rectangular area, end point information 10b, and image information 10c indicating the type of each image. Rectangular area information sorter 11
Has a start-point Y coordinate sorting circuit 11a for rearranging the Y-coordinates of the start points in a higher-order order according to the start-point information 10a, and storage control circuits 11b and 11c. The starting point Y coordinate sorting circuit 11a rearranges the initial rectangle starting point information 10a in the descending order of the Y coordinate, and becomes the new rectangular area starting point information 12a of the new rectangular area information storage unit 12.

[0012] Initial rectangle end point information 10b and image information 1
0c are rearranged by the storage control circuits 11b and 11c controlled by the start point Y coordinate sorting circuit 11a so as to correspond to the order of the new rectangular area start point information 12a. The new rectangular area image information 12c is obtained. Rectangular area subdivision section 13
A determination circuit 13a for determining the new rectangular area start point information 12a and determining whether the rectangular information is valid or invalid; an end point information 12b and an image information 12c under the control of the determination circuit 13a.
Storage control circuits 13b and 13c for performing storage control of
A rectangle information storage buffer 13d for temporarily storing the rectangle information of the subdivided rectangles in each subdivision process.

The subdivided rectangular area information storage section 14 stores start point information 14a and end point information 14b of subdivided rectangular areas sequentially sent from the rectangular information storage buffer 13d, and an image of each subdivided rectangular area. Is stored. FIG. 4 shows FIG.
FIG. 2 is a diagram specifically illustrating the mixed image 100 of FIG. 1. As can be seen from FIG. 4, all the lines in the line group (a) are rectangular information (X0, Y0), (XM, Y1),
A, and all the lines in the line group (b) are rectangular information [(X0, Y1), (X1, Y2),
A]; [(X1, Y1), (X2, Y2), B];
[(X2, Y1), (XM, Y2), A], and so on. As described above, although the description information is slightly increased by dividing the rectangular area, the data amount is overwhelmingly smaller than when the line control information is added for each line. Further, since the search for the rectangular area need only be performed once for the line group, the processing can be speeded up.

[0014]

According to the present invention, line control information for processing an image is described not in units of lines but in groups of lines, so that the data amount is significantly reduced as compared with the case of lines. Make it small. In addition, since the search for the image area only needs to be performed once for each line group, the processing speed is higher than the method using only the initial rectangular area.

[Brief description of the drawings]

FIG. 1 is a diagram showing the principle of the present invention.

FIG. 2 is a diagram showing a configuration of the present invention.

FIG. 3 is a diagram showing details of each unit in FIG. 2;

FIG. 4 is a diagram showing an operation example of the present invention.

FIG. 5 is a diagram for explaining line control information.

FIG. 6 is a diagram for explaining rectangular area information.

[Explanation of symbols]

 1, 2, 3, 4, 5 Rectangular area 2-1 Start point of rectangular area 2 2-2 End point of rectangular area 2 10 Initial rectangular area information storage unit 10a Rectangular area start point information 10b Rectangular area end point information 10c Rectangular area image information 11 Rectangular area information sort section 11a Start point Y coordinate sort circuit 11b, 11c Storage control circuit 12 New rectangular area information storage section 12a New rectangular area start point information 12b New rectangular area end point information 12c New rectangular area image information 13 Rectangular area subdivision section 13a Judgment Circuits 13b, 13c Storage control circuit 13d buffer 14 Subdivision rectangular area information storage unit 14a Subdivision rectangular starting point information 14b Subdivision rectangular end point information 14c Subdivision rectangular image information 100 Mixed image (1) to (4) Image type (a) ) To (i) Line groups L1, L2, L3 Lines A, B, C, D, E Image types (X, Y) Marks B0, B1 ... BM dot position

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) G06T 1/00-1/60 G06T 7/00-7/60 H04N 1/38-1/419 G03F 1 / 00-1/16

Claims (1)

(57) [Claims] In image processing for expressing a screen on which a plurality of types of images are mixed by a horizontal scanning line, initial rectangular area information defining a rectangular area of each image is represented by a rectangle.
Reorder the size of the Y coordinate of the start point of the upper left corner of the area
In this way, new rectangular area information is created, and the rectangular area of each image is created according to the order of the new rectangular area information.
The dividing line that passes along the upper and lower sides of the screen
To divide the rectangular area of each image into multiple
Generates a plurality of subdivided rectangular areas, and calculates the coordinates of the start point and end point of each subdivided rectangular area and the type of image.
Type to define a subdivided rectangular area
The method for determining a rectangular area, comprising: completing subdivided rectangular area information, and controlling a plurality of scanning lines between adjacent division lines by the same subdivided rectangular area information.