JP4969515B2 - Image forming apparatus, gradation graphic image drawing method, gradation graphic image drawing program, and recording medium - Google Patents

Description

  The present invention relates to the fields of an image forming apparatus, a gradation graphic image drawing method, a gradation graphic image drawing program, and a recording medium.

  FIG. 1 is a diagram illustrating the definition of an ellipse. An ellipse is represented by the radius of the ellipse (x_radius, y_radius) and the center point (Center Origin) of the ellipse. FIG. 2 is a diagram illustrating control points when an ellipse is converted into a Bezier curve. If an ellipse is converted into a Bezier curve, drawing can be performed by converting it into a Bezier curve having 12 coordinate points. Not only ellipses but also figures such as circles, rectangles, and triangles can be defined in the same way (for example, also referred to as vector format representation). When print data including graphics and the like is transmitted from the user terminal to the printer via the network, the print data can be transmitted by reducing the print data by using such a graphic representation method. For example, in PDL (Page Description Language), drawing can be instructed to the printer in a command format. The printer that has received the print data reproduces the figure from the definition, converts the figure into pixel data for printing, and then prints it on a print medium.

  Here, the case where the figure included in the print data is a gradation figure will be described. For example, if the printer analyzes the PDL syntax and a gradation figure is included, the printer draws (forms) the gradation figure. As a drawing method of a gradation figure, there is generally a method of drawing while gradually reducing the figure shape from the outside. For example, in the elliptical figure shown in FIG. 3, when the outer large ellipse is overwritten in order from the small ellipse, it is overwritten and drawn repeatedly in the same area. That is, the inner small ellipse region is drawn on the outer ellipse drawn so far. However, there is a problem that the memory access overhead becomes very large when the same area is drawn many times.

  Here, the portion to be overwritten is a portion that cannot be seen in the end, so it does not have to be actually drawn. Therefore, a method is also known in which ellipse figures are divided into a plurality of parts so that they do not overlap. FIG. 4 shows a state in which an ellipse-shaped area is created by being divided into a plurality of areas and drawn. An ellipse (elliptical shape region) 401 is obtained by cutting out the outermost region of the gradation ellipse into concentric circles (concentric similar figures). An ellipse 402 is obtained by cutting out concentric regions inside the ellipse 401 so as not to overlap. An ellipse 403 is obtained by cutting out concentric regions inside the ellipse 402 so as not to overlap each other, and drawing each region so that the regions do not overlap. By doing so, memory access can be suppressed.

  Note that gradation refers to a gradation change in gradation, and the gradation figure here is a figure drawn with a plurality of color tones where gradation changes in stages.

The inventions described in Patent Documents 1 and 2 are intended to speed up the drawing of gradation figures. According to these inventions, the drawing processing device and the printer device draw gradation figures faster than before. Is possible.
JP 2007-81886 A JP 2003-0721152 A

  By the way, in either of the drawing methods described above, in order to print with a printer, a process of converting a shape area into pixel data is required in the drawing process. This process is known as a scan line conversion process. In general, scan line conversion processing places a heavy load on a computer (CPU).

FIG. 5 is a diagram showing pixelation of a part of one concentric circle (elliptical area). In the elliptical region of FIG. 5, pixel data is obtained by obtaining two Bezier curves (outer curve and inner curve) and performing a scan run conversion process. Generally, in the scan line conversion process, the following process is performed.
(1) A Bezier curve is approximated to a straight line. A curve is expressed by making the curve into a collection of small straight lines.
(2) Find the coordinates through which the straight line passes. As this algorithm, there is a method of using an algorithm (Digital Differential Analyzer) which does not include real number calculation only by addition and subtraction.
(3) The coordinates obtained in (2) are sorted by Y coordinates (rearranged in order of decreasing Y coordinates).
(4) Inside / outside determination processing, determination processing inside and outside the region. There are Winding method and Even-odd method.
(5) Processing for clipping a scan line figure.

  Here, the prior art and the inventions described in Patent Documents 1 and 2 have a problem in that it is necessary to perform scanline conversion every time in order to obtain each concentric similarity shape constituting the gradation figure, and processing takes time. was there. For example, in order to draw a plurality of concentric figures such as ellipses 401, 402, and 403 as shown in FIG. 4, it is necessary to perform a scan line conversion process for each concentric figure to obtain pixel data.

  Accordingly, in the present invention, in view of the above problems, an image forming apparatus, a gradation figure image drawing method, a gradation, which efficiently draws constituent elements constituting a gradation figure, and accelerates the drawing process of the gradation figure image It is an object to provide a graphic image drawing program and a recording medium.

  Therefore, in order to solve the above-described problem, the image forming apparatus according to the present invention is a gradation figure composed of gradations that change stepwise from the outer edge of the figure toward the center point or from the center point of the figure toward the outer edge. In the image forming apparatus for forming the image, a gradation drawing width calculating means for calculating a gradation drawing width of the gradation figure, and the gradation drawing width calculated by the gradation drawing width calculating means, from an outer edge line of the gradation figure Inside, a shape line calculation means for calculating a similar shape line similar to the outer edge line, and only a region surrounded by the outer edge line and the similar shape line calculated by the shape line calculation means is converted into pixel data. Based on pixel data of the region converted by the pixel conversion means. And pixel generation means for generating inner pixel data from the outer edge line for each gradation drawing width, the pixel data converted by the pixel conversion means, and the pixel data generated by the pixel generation means. And a gradation color creating means for creating a color.

  In order to solve the above-mentioned problem, in the image forming apparatus, the shape line calculating unit scales the outer edge based on a scaling factor that is a value obtained by dividing the gradation drawing width by the distance value, and A similar shape line is calculated.

  In order to solve the above problem, in the image forming apparatus, the pixel data converted by the pixel conversion unit is expressed in a run-length format.

  In order to solve the above-mentioned problem, in the image forming apparatus, the generation unit reduces the run-length data and generates inner pixel data from the outer edge line for each gradation drawing width. To do.

  In order to solve the above problem, in the image forming apparatus, the y-coordinate data in the run-length format is rearranged in descending order.

  In addition, what applied the arbitrary combination of the component of this invention, expression, or a component to a method, an apparatus, a system, a computer program, a recording medium, etc. is also effective as an aspect of this invention.

  According to the present invention, an image forming apparatus, a gradation graphic image drawing method, a gradation graphic image drawing program, and a recording that efficiently draw components constituting the gradation graphic to speed up the drawing processing of the gradation graphic image A medium can be provided.

  The best mode for carrying out the present invention will be described below with reference to the drawings in each embodiment.

(Constitution)
First, before describing specific contents of the present invention, a network configuration for carrying out the present invention will be described. FIG. 6 is a network diagram in which an image forming apparatus 1 and a PC (Personal Computer) 2 according to the present invention are connected via a network 3. The image forming apparatus 1 is the image forming apparatus 1 according to the present invention. The image forming apparatus 1 according to the present invention receives print data including syntax described in PDL or the like transmitted from the PC 2 via the network 3, and performs image formation and printing based on (analyze) the syntax. To do. At this time, gradation data is included in the print data to be drawn and printed. Details of the image forming apparatus 1 will be described later. The PC 2 is a terminal on which a user performs printing or the like using the image forming apparatus 1 via the network 3 and is a general PC. The network 3 is a network including wired and wireless. FIG. 6 shows a configuration for explaining an embodiment of the present invention, and there may be any number of PCs.

  FIG. 7 is a hardware configuration diagram showing the main configuration of an embodiment of the image forming apparatus 1 according to the present invention. The image forming apparatus 1 mainly includes a CPU 702, a ROM (Read Only Memory) 703, a RAM (Random Access Memory) 704, and an NVRAM (Non-volatile Memory) 705 included in a controller 701 that controls the image forming apparatus 1. , An auxiliary storage device 706, an engine I / F (interface) 707, a panel I / F 708, a network I / F 709, a print engine 711, and a panel device 712.

  The CPU 702 includes a microprocessor and its peripheral circuits, and is a circuit that controls the entire project management server 1. The ROM 703 is a memory that stores a predetermined control program (software component) executed by the CPU 702. The RAM 704 executes various control operations by the CPU 702 executing a predetermined control program (software component) stored in the ROM 703. This is a memory used as a work area (work area) when performing. A VRAM 705 is a non-volatile memory that stores various setting information of printing conditions.

  The auxiliary storage device 705 is a device that stores a general-purpose OS (Operating System), various programs, and various types of information. For example, an HDD (Hard Disk Drive) that is a nonvolatile storage device is used. In addition to the auxiliary storage device 705, the various types of information may be stored in a storage medium such as a CD-ROM (Compact Disk-ROM) and a DVD (Digital Versatile Disk), and other media. Various kinds of information stored in can be read via a drive device such as a storage medium reader (not shown). Therefore, various information can be obtained by setting the recording medium in the storage medium reading device as necessary.

  The engine I / F 707 is an interface that issues a print instruction with the print engine 711. The panel I / F 708 is an interface with the panel device 712 for the user to perform various input operations. Panel device 712 includes a mouse, a keyboard, a touch panel switch provided so as to be superimposed on the display screen of the display device, and the like. The network I / F 709 is a network interface that communicates with the PC 2 via the network 3 and supports communication according to various network forms including a wired network and a wireless network.

(function)
The image forming apparatus 1 according to the present invention receives print data including syntax described in PDL transmitted from the PC 2 via the network 3 (and network I / F 709), forms an image based on the syntax, and performs printing. To do. At this time, gradation data is included in the print data to be drawn and printed. The image forming apparatus 1 according to the present invention efficiently draws components (pixel data) constituting a gradation graphic by the image forming method according to the present invention, thereby speeding up the gradation graphic image drawing process. . Specifically, the image forming apparatus 1 according to the present invention executes a process (scan line conversion process) for obtaining a pixel (data) of a concentric similar figure constituting a gradation figure only once, and the pixel (data). The pixel shape (pixel data) of the entire gradation figure is obtained by enlarging / reducing (scaling) the information. In the present embodiment, the graphic will be described using the elliptical graphic used in the above-described example. Therefore, the image forming apparatus 1 according to the present embodiment performs a process of drawing (forming) a gradation ellipse. This will be described in detail below.

  FIG. 8 is a functional block diagram showing main functions of an embodiment of the image forming apparatus 1 according to the present invention. The image forming apparatus 1 includes a syntax analysis unit 801, a gradation shape creation unit 802, and a gradation color creation unit 803 as main functions according to the present invention.

  The syntax analysis unit 801 performs syntax analysis on print data for each type of syntax related to printing, such as PDL, and extracts information related to printing. For example, it analyzes and extracts text such as characters, drawing data such as images and vector graphics, and drawing setting information such as colors, gradation patterns, and transparency settings. PDL (page description language) is one of programming languages for instructing a printer to perform drawing.

The gradation shape creation unit 802 acquires drawing data and drawing setting information from the syntax analysis unit 801 and creates a gradation shape. The creation of the gradation shape includes pixel (data) processing by the scanline conversion processing described above. Therefore, the gradation shape creation unit 802 creates pixels (data) that form the gradation shape from the drawing data.
Details will be described later.

  The gradation color creation unit 803 creates the color of the pixel data constituting the gradation shape created by the gradation shape creation unit 802 based on the drawing setting information analyzed by the syntax analysis unit 801.

  FIG. 9 is a diagram for explaining the gradation shape creation unit 802 in detail. The gradation shape creation unit 802 includes a gradation drawing width calculation unit 901, a shape line calculation unit 902, a pixel conversion unit 903, and a pixel generation unit 904.

  The gradation drawing width calculation unit 901 calculates a gradation drawing width in which one color is continuous in a gradation graphic composed of a plurality of colors. That is, the gradation figure has a color stage in which the color is continuously changed from a certain color to a certain color, but the gradation drawing width calculation unit 801 uses the same color until the certain color changes to the next certain color. Calculate the number of pixels you have.

  The shape line calculation unit 902 determines the first graphic shape that is the outer edge line of the gradation graphic from the definition of the graphic shape, and resembles the outer edge line from the gradation drawing width calculated by the gradation drawing width calculation unit 901. A second figure shape which is a similar shape line is calculated. For example, when the first figure shape is an oval (outer edge) oval shape curve (a curve that draws an ellipse), the second oval shape is an oval shape curve inside the oval oval shape, and the color Is an elliptical curve that is also a boundary line that changes to the next color. The elliptical curve calculated here is expressed by a cubic Bezier curve, for example.

  The pixel conversion unit 903 converts a region formed by being surrounded by the first graphic shape and the second graphic shape into pixel data. That is, the pixel conversion unit 903 is a functional unit that performs the above-described scan line conversion process.

  The pixel generation unit 904 generates pixel data inside the graphic shape based on the pixel data converted by the pixel conversion unit 903. Based on the pixel data converted by the pixel conversion unit 903, the pixel generation unit 904 repeats scaling (reduction scaling) of the pixel data, so that pixel data constituting the gradation graphic image (entire) is created. Will be.

  Note that these functions are actually realized by a program (image forming program) executed by the CPU 702.

(Gradation shape creation process)
Next, details of processing in which the image forming apparatus 1 according to the present invention creates pixel data constituting a gradation graphic image (entire) will be described. FIG. 10 is a flowchart showing processing by the gradation shape creation unit 802. This will be described with reference to this. In the present embodiment, the graphic will be described using the elliptical graphic used in the above-described example. Therefore, the image forming apparatus 1 according to the present embodiment performs a process of drawing (forming) a gradation ellipse.

  First, using FIG. 1 again, the definition of an elliptical figure will be briefly described. The center coordinate of the elliptical figure Center Origin is a coordinate at which the elliptical pattern starts. The radius of the ellipse figure is defined by two radii. Radius (x_radius, y_radius). End Origin is a coordinate at which the elliptic pattern ends. Note that the color gradation of the ellipse changes linearly from the color at the start coordinate Center Origin to the color at the end coordinate End Origin. This will be described below based on this.

  Steps S1001 to 1003 are steps performed by the gradation drawing width calculation unit 901. In step S1001, the distance between two points is obtained from the coordinates of Center Origin and End Origin. This distance is defined as Grad_width. If the distance is not unique depending on the shape of the figure, the maximum distance is used.

In step S1002, a difference is obtained for each of the color component in Center Origin and the color component in End Origin, and the maximum value is set as a color change width Color_width. For example, if the color of Center Origin is RGB color (R, G, B) = (255, 100, 80) and the color of End Origin is RGB color (R, G, B) = (128, 50, 10) The difference between each component in RGB is as follows.
ΔR = 255-128 = 127
ΔG = 100-50 = 50
ΔB = 80-10 = 70
Since the maximum value of each difference is the R component difference 127, in this case, 127 is Color_width. Thus, in step S1002, the value of Color_width is obtained.

In step S1003, a gradation drawing width is obtained. The gradation drawing width can be obtained as follows.
Gradation drawing width = Grad_width / Color_width
The gradation drawing width can be said to be a pixel to be drawn when the color changes. The reciprocal of this value is the amount of color that changes every time one pixel is drawn.

  Steps S1011 to 1012 are steps performed by the shape line calculation unit 902, and calculate an inner oval shape curve (second figure shape which is a similar shape line similar to the outer edge line) from the gradation drawing width. . The inner elliptic curve is also a boundary line that changes from the outer elliptic curve. FIG. 11 is a diagram showing a region 113 surrounded by two elliptical curves. The outer elliptic curve (curve 111) is the outer edge line of the ellipse obtained from the definition of the ellipse figure (ellipse radius and center point coordinates). The inner elliptic curve (curve 112) is obtained as follows.

In step S1011, Scale_rate is obtained. Scale_rate is the rate of shape change,
Scale_rate = Gradation width / Grad_width
Sought by.

In step S1012, the radius of the inner elliptic curve (curve 112) is obtained. The radius of the curve 112 is obtained by multiplying the radius of the curve 111 by Scale_rate.
Radius X = x_radius * Scale_rate of inner elliptic curve (curve 112)
Radius of inner elliptic curve (curve 112) Y = y_radius * Scale_rate
As described above, the inner elliptical curve (curve 112) can be obtained. Since the curve 112 is similar to the curve 111, the center point coordinates are the same as the center point coordinates of the curve 111.

  Step S1021 is a step performed by the pixel conversion unit 903. A region formed by being surrounded by the first graphic shape and the second graphic shape is converted into pixel data. That is, the pixel data of the region 113 surrounded by the curve 111 and the curve 112 is obtained. The conversion processing to pixel data may be performed by scanline conversion processing (a known technique). For example, when conversion to pixel data is performed, the data is converted to run-length data as shown in FIG. In FIG. 12, “y” is the Y coordinate value of each pixel, “sx” is the start x coordinate of the obtained shape pixel, “ex” is the end coordinate of the obtained shape pixel (note that the drawing pixel includes the end coordinate) ). y = 0 indicates that there are drawing pixels between 10 and 19 of the x coordinate. y = 1 indicates that there are drawn pixels between 9 and 20 in the x coordinate. y = 2 indicates that there are drawing pixels from 8 to 9 in the x coordinate, and there are drawing pixels from 20 to 21 in the x coordinate. FIG. 13 is a diagram representing the run-length data in FIG. 12 as pixel data. Data obtained by performing the scan line conversion on the area 113 (for example, data in the run length format in FIG. 12) is retained for use in the subsequent creation of gradation shapes.

  Steps S1031-1036 are steps performed by the pixel generation unit 904. Based on the region 113 surrounded by the two elliptical curves (curve 111 and curve 112) created in step S1021, pixels (data) of the next inner region are obtained. If it demonstrates using FIG. 14, the pixel (data) of the area | region 113-2 will be calculated | required. In addition, as described with reference to FIG. 4, pixel data of an area corresponding to an ellipse (shape area) 401 is obtained by the pixel conversion unit 903 in step S1021. In this step, the pixel data of the area corresponding to the ellipse 402 is obtained based on the pixel data of the area corresponding to the ellipse 401. If the pixel data of the area corresponding to the ellipse 402 is obtained, the same process is repeated to obtain the pixel data of the area corresponding to the ellipse 403. Hereinafter, processing for obtaining pixels (data) of the next inner region 113_2 will be described with reference to FIGS.

  Proceeding to step S1031, the start row of area 113_2 is obtained. In FIG. 12 (data indicating the pixel position of the region 113), the row where the drawing of the shape of the region 113_2 is started is the row having the smallest y coordinate among the y rows having two pixel run data in the same row. . Specifically, in the example of FIG. 12, y = 2 is a drawing start line (start y line).

  Proceeding to step S1032, pixels are generated from the start line obtained in step S1031 so that there is no gap with respect to the gradation drawing width line and subsequently to the outer pixel (area 113). The method for generating the pixels is as follows. There are two pixel run data in the same y-coordinate row. In the example of FIG. 12, pixel run data with y = 2 is data with “y = 2, sx = 8, ex = 9” and “y = 2, sx = 20, ex = 21”. When called the left pixel run data and the right pixel run data, respectively, the value obtained by adding 1 to the end point ex of the left pixel run data is set as the starting point sx_2 (= ex + 1) to prevent the gap from occurring. )become. Similarly, the end point is a value obtained by subtracting 1 from the start point sx of the right pixel run data to obtain the end point ex_2 (= sx-1). As a result, pixel run data “y = 2, sx_2 = 10, ex_2 = 19” is obtained. This is repeated for the gradation drawing width line. In the present embodiment, pixel run data “y = 3, sx_2 = 9, ex_2 = 20” is further obtained. FIG. 15 is a diagram showing the pixels thus obtained.

  Proceeding to step S1033, the end row of area 113_2 is obtained. In FIG. 12 (data indicating the pixel position of the area 113), the line where the drawing of the shape of the area 113_2 is finished is the line with the largest y coordinate among the y lines having two pixel run data in the same line. . Specifically, in the example of FIG. 12, y = 9 is the drawing end line (end y line).

  Proceeding to step S1034, pixels are generated from the end line obtained in step S1033 so that there is no gap with respect to the gradation drawing width line and subsequently to the outer pixel (area 113). The method for generating the pixels is as follows. There are two pixel run data in the same y-coordinate row. In the example of FIG. 12, the pixel run data of y = 9 is data of “y = 9, sx = 8, ex = 9” and “y = 9, sx = 20, ex = 21”. If we call them left pixel run data and right pixel run data, respectively, the value obtained by adding 1 to the end point ex of the left pixel run data is the starting point sx_2 (= ex + 1) to be obtained. become. Similarly, the end point is a value obtained by subtracting 1 from the start point sx of the right pixel run data to obtain the end point ex_2 (= sx-1). As a result, pixel run data “y = 9, sx_2 = 10, ex_2 = 19” is obtained. This is repeated for the gradation drawing width line. In the present embodiment, pixel run data “y = 8, sx_2 = 9, ex_2 = 20” is further obtained. FIG. 16 is a diagram showing the pixels thus obtained.

  Proceeding to step S1035, pixels in a row not yet obtained are created as data having two pixel run data in one row. For the start point sx_2 of the left pixel run data having the shape of the region 113_2, a value obtained by adding 1 to the end point ex of the left pixel run data of the same row in the region 113 is the start point sx_2 (= ex + 1) to be obtained. In the example of FIG. 12, since ex = 7 in the row of y = 4, the start point sx_2 = ex + 1 = 8 is obtained.

  The end point ex_2 of the left pixel run data having the shape of the region 113_2 is a value obtained by adding the start point sx_2 to the width (ex-sx) of the left pixel run data of the same row in the region 113. In the example of FIG. 12, since the left pixel run data is “y = 4, sx = 6, ex = 7” in the row of y = 4, the end point to be obtained ex_2 = (ex-sx) + sx_2 = (7-6 ) + 8 = 9.

  Next, the right pixel run data (second pixel run data in the same row) having the shape of the region 113_2 can be similarly obtained from the right pixel run data in the same row of the region 113.

  For the end point ex_2 of the right pixel run data having the shape of the region 113_2, a value obtained by subtracting 1 from the start point sx of the right pixel run data of the same row in the region 113 is the end point ex_2 (= ex-1) to be obtained. In the example of FIG. 12, since sx = 22 in the line y = 4, the obtained end point ex_2 = sx-1 = 21.

  The start point sx_2 of the right pixel run data having the shape of the region 113-2 is a value obtained by subtracting the width (ex-sx) of the right pixel run data of the same row in the region 113 from the end point ex_2. In the example of FIG. 12, since the right pixel run data is “y = 4, sx = 22, ex = 23” in the row of y = 4, the start point sx_2 = ex_2- (ex-sx) = 21- ( 23-22) = 20. FIG. 17 is a diagram showing the pixels thus obtained. The remaining rows are processed in the same manner to obtain the pixels shown in FIG. The condition for ending step S1035 is when there are no two pixel run data in one row. As described above, all the pixel data of the region 113_2 have been obtained so far. As described above, the process is actually performed with the run-length data. FIG. 18 shows run-length format data indicating the area 113_2 generated by the above processing. Compared with FIG. 12 and FIG. 18, the number of y rows decreases and the width (ex-sx) of the pixel run data decreases (shrinks) as the figure is inside the large figure. It turns out that it is shrinking as a whole.

  Proceeding to step S1036, if there is an inner region where no pixel is generated, the process proceeds again to step S1031, and the above-described processing is repeated. Finally, all pixel data inside the ellipse shape is generated, and the inside of the ellipse shape is filled with pixels. FIG. 19 shows an example of the oval figure finally formed. Pixel data as shown in FIG. 19 is generated, and the elliptical figure is represented by the pixel data. In addition, although it often demonstrated with the figure using a pixel and a coordinate, as above-mentioned, the process is actually performed with the data of run length format. This is because pixel coordinate information can be easily extracted by handling pixel data in a run-length format. In order to make the data easier to handle, in the run-length data, the rows are rearranged in ascending order of the y coordinate.

  As described above, the gradation shape creation unit 802 generates pixel data of the entire elliptical figure. Next, the gradation color creation unit 803 creates (appends) a color corresponding to each pixel data.

(Gradation color creation process)
Next, details of a process in which the image forming apparatus 1 according to the present invention creates gradation colors will be described. The gradation color creation unit 803 creates the color of the pixel data constituting the gradation shape created by the gradation shape creation unit 802 based on the drawing setting information analyzed by the syntax analysis unit 801. The pixel data of the entire ellipse figure has been generated by the above-described gradation shape creation unit 802. Here, the process of creating (attaching) a corresponding color for each pixel data by the gradation color creation unit 803 will be described. Do.

  Here, the color values used in the description of the gradation drawing width calculation unit 902 (steps S1001 to 1003) are used again. That is, the color of Center Origin is RGB color (R, G, B) = (255, 100, 80), and the color of End Origin is RGB color (R, G, B) = (128, 50, 10). . As described above, the gradation drawing width is obtained by Grad_width / Color_width, which is equal to the number of pixels to be drawn during the same period of the R component having the largest change width.

Here, the drawing width in which the color changes for each color component is obtained as follows. Grad_width is the distance between two points in the coordinates of Center Origin and End Origin.
R component drawing width = Grad_width / R component change (ΔR)
G component drawing width = Grad_width / G component variation (ΔG)
B component drawing width = Grad_width / B component variation (ΔB)
To explain this with specific numerical values, if Grad_width is 1000,
R component drawing width = 1000 / (255-128) = 7.874
G component drawing width = 1000 / (100-50) = 20
B component drawing width = 1000 / (80 -10) = 14.28
It becomes.

Since the gradation drawing width is the R component drawing width, the R component changes by 1 each time each gradation region is drawn. The color amount (color change amount) that changes for each gradation shape is obtained as follows.
R color change amount = gradation drawing width / R component drawing width = 7.874 / 7.874 = 1.0
G color change amount = gradation drawing width / G component drawing width = 7.874 / 20 = 0.3937
B color change amount = gradation drawing width / B component drawing width = 7.874 / 14.28 = 0.551
this is,
The R value changes by 1 for each region.
The G value changes by 0.3937 for each region.
The B value changes by 0.551 for each region.
Means that. For example, referring to FIG. 19, this area corresponds to the area 113, the areas 113_2, and 113_3. Here, the amount of change in the R, G, and B values for each region is set as R_delta, G_delta, and B_delta, respectively.

Specifically, a case where the gradation color of the gradation ellipse is drawn (created) from the outside to the inside will be described as an example. First, the gradation color (R, G, B) of the outermost region (for example, corresponding to the region 113) is (128, 50, 10).
No1 = (128, 50, 10)
It expresses.
Here, if the reference RGB values are CR, CG and CB, respectively,
CR = 128
CG = 50
CB = 10
It is.

The gradation color (R, G, B) of the next inner area (for example, corresponding to the area 113_2) is obtained.
R = CR + R_Delta = 128 + 1 = 129.0
G = CB + G_Delta = 50 + 0.3937
B = CG + B_Delta = 10 + 0.551
If you round off the decimal point, use the Round function:
R = Round (CR + R_Delta) = Round (128 + 1) = Round (129.0) = 129
G = Round (CB + G_Delta) = Round (50 + 0.3937) = Round (50.3937) = 50
B = Round (CG + B_Delta) = Round (10 + 0.551) = Round (10.551) = 10
Therefore, the gradation color (R, G, B) of the next inner area is
No2 = (129, 50, 10)
It becomes.
Then, the reference RGB values CR, CG, CB are updated.
CR = 129.0
CG = 50.3937
CB = 10.551
For the reference RGB values CR, CG, and CB, values before round function processing are used. This is because the color expression accuracy is higher than the value after the round function processing.

Further, the gradation color (R, G, B) of the next inner area (for example, corresponding to the area 113_3) is obtained in the same manner.
R = Round (CR + R_Delta) = Round (129 + 1) = Round (130.0) = 130
G = Round (CG + G_Delta) = Round (50.3937 + 0.3937) = Round (50.7874) = 50
B = Round (CB + B_Delta) = Round (10.551 + 0.551) = Round (11.102) = 11
Therefore, the gradation color (R, G, B) of the next inner area is
No3 = (130, 50, 11)
It becomes.
Then, the reference RGB values CR, CG, CB are updated.
CR = 130.0
CG = 50.7874
CB = 11.102
In this way, the gradation color (R, G, B) for each region can be obtained.

  As described above, the gradation color creation unit 803 creates a corresponding color for each pixel data of the entire elliptical figure. This completes a gradation figure (in this embodiment, a gradation ellipse). The gradation graphic is developed and printed in a frame (print frame) after a predetermined image correction process or the like.

  As described above, the image forming apparatus 1 according to the present embodiment executes the process for obtaining the pixel information of the concentric similar figure constituting the gradation ellipse only once, and uses the pixel information to perform a plurality of scan lines. A gradation figure shape can be created without performing conversion. That is, in order to obtain a concentric similar figure as in the prior art, the gradation figure shape creation process can be performed at a higher speed than in the case where the scanline conversion process must be performed every time.

  According to the present invention, there are provided an image forming apparatus, an image forming method, an image forming program, and a recording medium that efficiently draw components constituting a gradation graphic to speed up the drawing process of the gradation graphic image. It becomes possible.

  Note that the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. In the embodiment, the gradation ellipse has been described, but this can be applied to, for example, a gradation circle. This is because if two radii (x_radius, y_radius), which are parameters representing an elliptical shape, are equal, a circle is formed. According to the same technical idea, it can be applied to a gradation rectangle (rectangle), a gradation triangle, and the like. The technical idea of the present invention is that the gradation drawing width corresponding to one color constituting the gradation figure is converted into pixel data, all the remaining pixel data is created based on the pixel data, and the gradation figure drawing process is performed. Therefore, any gradation graphic shape that can be applied within the scope of the technical idea of the present invention may be used.

It is a figure which shows the definition of an ellipse. It is the figure which showed each control point at the time of converting an ellipse into a Bezier curve. It is an example of the figure which shows drawing of a gradation figure. It is an example of the figure which shows drawing of a gradation figure. It is a figure which shows pixelation of the part of one concentric circle. 1 is a network diagram according to an embodiment of the present invention. 1 is a hardware configuration diagram showing a main configuration of an embodiment of an image forming apparatus 1 according to the present invention. 1 is a functional block diagram showing main functions of an embodiment of an image forming apparatus 1 according to the present invention. It is a figure explaining a gradation shape creation part. It is a flowchart which shows the process by a gradation shape creation part. It is a figure which shows the area | region enclosed by two elliptical curves. It is a figure which shows the data of a run length format. It is the figure which expressed the data of run length format with pixel data. It is a figure explaining an inner area | region. It is a figure explaining pixel generation. It is a figure explaining pixel generation. It is a figure explaining pixel generation. It is a figure which shows the data of a run length format. It is a figure explaining pixel generation.

Explanation of symbols

1 Image forming apparatus 2 PC
3 Network 701 Controller 702 CPU
203 ROM
704 RAM
705 NVRAM
706 Auxiliary storage device 707 Engine I / F
708 Panel I / F
709 Network I / F
711 Print engine 712 Panel device 801 Parsing unit 802 Gradation shape creation unit 803 Gradation color creation unit 901 Gradation drawing width calculation unit 902 Shape line calculation unit 903 Pixel conversion unit 904 Pixel generation unit

Claims (14)

In an image forming apparatus for forming an image of a gradation figure composed of gradations that change stepwise from the outer edge of a figure toward the center point or from the center point of the figure toward the outer edge,
A gradation drawing width calculating means for calculating a gradation drawing width of the gradation figure;
Shape line calculation means for calculating a similar shape line similar to the outer edge line, inside the outer edge line of the gradation figure, by the gradation drawing width calculated by the gradation drawing width calculation means;
Pixel conversion means for converting only the region surrounded by the outer edge line and the similar shape line calculated by the shape line calculation means into pixel data;
Pixel generation means for generating inner pixel data from the outer edge line for each gradation drawing width based on the pixel data of the region converted by the pixel conversion means;
A gradation color creating means for creating a color corresponding to the pixel data converted by the pixel converting means and the pixel data generated by the pixel generating means;
An image forming apparatus comprising: The gradation drawing width calculation means divides the distance value from the center point to the outer edge line by the maximum difference value among the difference values between the color component values at the center point and the color component values at the outer edge line. And calculating the gradation drawing width,
The image forming apparatus according to claim 1. The shape line calculating means reduces the outer edge based on a scaling factor that is a value obtained by dividing the gradation drawing width by the distance value, and calculates the similar shape line.
The image forming apparatus according to claim 1, wherein: The pixel data converted by the pixel converting means is expressed in a run-length format;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The generation means reduces the data in the run length format to generate inner pixel data from the outer edge line for each gradation drawing width;
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The run-length y-coordinate data is sorted in descending order;
The image forming apparatus according to claim 4, wherein: In a gradation graphic image drawing method in an image forming apparatus that forms an image of a gradation graphic composed of gradations that change stepwise from the outer edge of a graphic toward the center point or from the central point of the graphic toward the outer edge,
A gradation drawing width calculating procedure for calculating a gradation drawing width of the gradation figure;
A shape line calculation procedure for calculating a similar shape line similar to the outer edge line inside the outer edge line of the gradation figure by the gradation drawing width calculated by the gradation drawing width calculation procedure;
A pixel conversion procedure for converting only a region surrounded by the outer edge line and the similar shape line calculated by the shape line calculation procedure into pixel data;
A pixel generation procedure for generating inner pixel data from the outer edge line for each gradation rendering width based on the pixel data of the region converted by the pixel conversion procedure;
A gradation color creating procedure for creating a color corresponding to the pixel data converted into the pixel converting procedure and the pixel data generated by the pixel generating means;
A graphic image drawing method characterized by comprising: The gradation drawing width calculation procedure divides the distance value from the center point to the outer edge line by the maximum difference value among the difference values between the color component values at the center point and the color component values at the outer edge line. And calculating the gradation drawing width,
The gradation graphic image drawing method according to claim 7. The shape line calculation procedure is based on a scaling factor that is a value obtained by dividing the gradation drawing width by the distance value, and scales the outer edge to calculate the similar shape line.
The gradation graphic image drawing method according to claim 7 or 8. The pixel data converted by the pixel conversion procedure is expressed in a run-length format;
The gradation graphic image drawing method according to claim 7, wherein: The generation procedure includes reducing the run-length format data to generate inner pixel data from the outer edge line for each gradation drawing width.
The gradation graphic image drawing method according to claim 7, wherein: The run-length y-coordinate data is sorted in descending order;
The gradation graphic image drawing method according to claim 10 or 11, characterized in that:   A gradation graphic image drawing program for causing a computer to execute the gradation graphic image drawing method according to any one of claims 7 to 12.   A computer-readable recording medium on which the gradation graphic image drawing program according to claim 13 is recorded.