JPH07200818A - Image processing device - Google Patents

Abstract

(57) [Abstract] [Purpose] An anti-aliasing process is performed by using an optimal sub-pixel filter for an output device without any burden on the operator, and the best image is always obtained. [Structure] The CPU 2 of the image processing apparatus 1 has an output device 2
Of the plurality of sub-pixel filters stored in the non-volatile RAM 6, the output device 20, which is switched and connected through the output switching unit 8 among 0, 20a ... A different filter is selected, vector information of the image input from the host machine 10 is anti-aliased using the filter, and density data is written in the frame memory 5 for each pixel of the image. The image data formed on the frame memory 5 is output to the output device 20.
Output to and displayed or printed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for performing anti-aliasing processing for removing jaggies at an edge portion of an image.

[0002]

2. Description of the Related Art When an image such as a graphic is displayed or printed by an output device such as a display device or a printer, a large number of pixels (hereinafter also referred to as "pixels") are arranged in a row in the horizontal direction (main scanning direction). It is well known to form a line and form a large number of lines in the vertical direction (sub-scanning direction) to form an image.

For example, as a display device, a monochrome or color CRT (CRT), LCM (liquid crystal matrix) is used.
There are printers such as electrophotographic type LBP (laser beam printer), LEDA (light emitting diode array), LCA (liquid crystal array), sublimation type or melting type thermal printer, wire dot printer and ink jet printer. There is a printer etc.

When an image is displayed or printed by using such an output device, it does not matter if the edges of the regions having different densities or colors are close to vertical or strictly horizontal, but diagonally particularly close to horizontal. The jaggies (also called aliases) in which the edge part looks like a stepped jagged part become more prominent, and the more the density difference or the hue difference between the regions on both sides of the edge part is, the more marked it becomes.

Particularly in the field of computer graphics, jaggies are relatively inconspicuous in high-resolution LBPs, etc., but CR in which the number of lines (the number of scanning lines) is limited.
When displaying with T and LCM (liquid crystal matrix), it is easy to stand out. In particular, since the upper and lower parts of a circle are extremely horizontal and jaggies appear in the LBP, the density or brightness of the pixel at the edge portion is changed by the anti-aliasing process so that the circle looks visually smooth.

The anti-aliasing process is a process for determining the density or brightness of a pixel that intersects with a vector indicating an edge portion, in accordance with the contribution rate (area ratio, etc.) of the portion that is bisected by the vector and remains. Yes, the uniform averaging method, the weighted averaging method, the convolution integration method, etc. are generally used.

The uniform averaging method is the simplest of these, but since the method of expressing the intermediate density differs depending on the output device, the density may differ between the left side and the right side of the density area. At that time, a weighted averaging method using an optimum subpixel filter according to the output device was used.

[0008]

However, a configuration in which only one type of output device is connected to the image processing device is rare, and at least a display device such as a CRT and a printer for recording the image displayed on the display device are used. A configuration in which various types of output devices are connected is common.

In such a case, if the same sub-pixel filter is used in the display device and the printer, an optimum image cannot be obtained for each, and either one should be emphasized.
You will have to put up with a sub-pixel filter that has an intermediate property between them. Otherwise, it is necessary to prepare two optimal subpixel filters for each and select and instruct according to the output device.

To this end, the operator must remember which sub-pixel filter is used for which output device, and if the number of sub-pixel matrices into which a pixel (pixel) is divided is different, each sub-pixel filter is different. Therefore, there is a problem in that if an incorrect instruction is given, the result will be worse than in the case where one sub-pixel filter is also used.

Further, it may be a system in which a plurality of terminals (each of which has a dedicated display device) each having an image processing device connected to each other via a LAN use an available printer among the plurality of printers. For example, the operator must check which printer to use each time and select the optimum sub-pixel filter with the same number of matrices, which increases the operator's burden and tends to cause a selection error. Occur.

The present invention has been made in view of the above points, and the image processing apparatus always uses the optimum subpixel filter according to the output apparatus without imposing any burden on the operator, so that the best image can always be obtained. Is intended to be obtained.

[0013]

In order to achieve the above object, the present invention processes vector data of an image input from a host machine to form image data, and outputs the image data to an output device connected thereto. In an image processing apparatus that outputs or displays or prints an image, in order to obtain an anti-aliasing processing unit that performs anti-aliasing processing based on vector data and a contribution ratio of edge pixels when the processing unit performs the anti-aliasing processing. Used for the anti-aliasing processing means by selecting one of the plurality of sub-pixel filters having different characteristics from each other and one of the plurality of sub-pixel filters according to the type of the connected output device. The selection means is provided.

In the above-mentioned image processing apparatus, the filter selection means detects the type of the output device connected and identifies it, and selects a sub-pixel filter according to the identified type of output device to perform anti-aliasing processing. It is recommended that the means be used by the means.

Alternatively, the filter selection means inputs the information of the type of the output device from the host machine or the connected output device, selects the sub-pixel filter according to the input information and uses it as the anti-aliasing processing means. It may be a means for causing it.

Alternatively, the filter selection means inputs the information of the type of subpixel filter suitable for the type of the output device from the host machine or the connected output device, and selects the subpixel filter according to the input information. Alternatively, the anti-aliasing processing means may be used as the means.

Alternatively, an image processing apparatus for processing vector data of an image input from a host machine to form image data and outputting the image data to a connected output device to display or print the image. , Anti-aliasing processing means for performing anti-aliasing processing based on vector data, and data of a sub-pixel filter used by the processing means for obtaining a contribution rate of edge portion pixels when performing the anti-aliasing processing to a host machine or connection Image processing apparatus provided with means for inputting from an output device that is used and causing the anti-aliasing processing means to use it.

[0018]

In the image processing apparatus configured as described above, among the plurality of sub-pixel filters having different characteristics, which are provided in advance and are used for obtaining the contribution rate of the edge pixel when performing the anti-aliasing processing. The filter selecting means selects any one of them according to the type of the output device connected, and causes the anti-aliasing processing means to use the selected one.

Further, in the above image processing apparatus, the type of the output device to which the filter selecting means is connected is detected and identified, and any one of the plurality of sub-pixel filters is selected according to the identified type of the output device. One of them is selected and used by the anti-aliasing processing means.

Alternatively, the filter selection means inputs information indicating the type of the output device from the host machine or the connected output device, and selects any one of the plurality of subpixel filters according to the information. Then, the anti-aliasing processing means is used.

Alternatively, the filter selecting means inputs the information of the type of sub-pixel filter suitable for the type of the output device from the host machine or the connected output device, and selects the sub-pixel filter of the type indicated in the information. Selected for use by anti-aliasing means.

In any case, the anti-aliasing processing means uses the sub-pixel filter selected by the filter selecting means to perform the anti-aliasing processing based on the vector data of the image input from the host machine. The image data formed by the processed result is output to a connected output device and displayed or printed.

Alternatively, the image processing apparatus provided with the means for inputting the data of the above sub-pixel filter obtains the contribution rate of the edge pixel when performing the anti-aliasing processing from the host machine or the connected output device. Input the data of the sub-pixel filter according to the connected output device used.

The anti-aliasing processing means uses the input sub-pixel filter data to perform anti-aliasing processing based on the vector data of the image input from the host machine. The image data formed by the processed result is output to a connected output device and displayed or printed.

Therefore, in any of the above-mentioned image processing devices, the anti-aliasing process is performed using the optimum sub-pixel filter for the connected output device without bothering the operator, so that the best image is always obtained. To be

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be specifically described below with reference to the drawings. Generally, in image processing, the entire screen is divided into areas surrounded by closed curves (edges) and having uniform hues and densities, and these areas are set as a group and predetermined processing is performed for each group.

When the edge is a curve, it is decomposed into a plurality of straight lines (vectors) according to its curvature. That is, the larger the curvature (smaller radius of curvature), the smaller the number of short vectors, and the smaller the curvature (larger radius of curvature), the smaller the number of long vectors.

These vector groups rotate clockwise or counterclockwise from a certain point as the starting point, and the end point of the last vector becomes the starting point of the first vector so that the end point of one vector becomes the starting point of the next vector. The vector data of one group are input / output as a set of coordinates of the start point and the end point of each vector.

FIG. 4 is a flow chart showing an example of an image processing routine commonly used by the respective embodiments described later. FIG. 5 is a diagram showing an example of a graphic processed by the routine shown in FIG. 4, and each vertex P0, P1, P of the graphic
The coordinates of 2 are (X0, Y0), (X1, Y1), (X2,
Y2).

With reference to the flow chart shown in FIG. 4, the image processing routine including the anti-aliasing processing shown in steps 9 to 12 will be described with reference to the figure shown in FIG. 5 which is one of the groups of images as an example. Each will be described.

(Step 1): Graphic information, which is image data, is input from the host machine in group units. The graphic information may be input for all the groups at once, or for each group when the memory has no space. Next, the input graphic information forming a closed curve for one group is expanded into vector information (decomposed into many straight line vectors). When vector information is input from the host machine, step 1 is omitted.

(Step 2): Vector information for one group is registered in the first edge table ET (1).
That is, as shown in Table 1, the figure shown in FIG. 5A has the vector names A, B, and C as well as the coordinate values (X
s, Ys) (Xe, Ye) is written to the table. As is clear from Table 1, at this point, the end point of the vector A and the start point of the vector B, the end point of the vector B and the start point of the vector C, the end point of the vector C and the start point of the vector A are P1 and P, respectively.
2 and P0 match each other.

(Step 3): Among the vectors of ET (1), for the vector whose Ye at the end point is larger than Ys at the start point, the direction of the vector is reversed by replacing X and Y at the start point and the end point. Is re-registered in the second edge table ET (2). That is, as shown in FIG. 5B and Table 2, the vector B is left as it is and the directions of the vectors A and C are reversed and re-registered.

(Step 4): The maximum value Ys max and the minimum point Ye min of the group are determined by searching the maximum value of Ys at the start point and the minimum value of Ye at the end point of each vector of ET (2). By doing so, the processing range in the height direction (Y direction) of this group, that is, the Y region is set. That is, the highest point is P1 (X1, Y1) and the lowest point is P2 (X1
2, Y2), and the Y region is Y1 to Y2.

(Step 5): Set Y area (Y1
For Y2), first lower the horizontal Y line by one line from the one with the largest Y value and, in order to determine the intersection with the vector, first discard the coordinates Ys max of the highest point in decimal units below the decimal point in line pitch units. This value is the first value of the coordinate value Yh of the Y line.

(Step 6): Only the information of the vector intersecting the Y line is selected from ET (2) and registered in the active edge table AET. That is, the starting point is Ys> Y
When the value becomes h, the information of the vector is registered in the AET, and when the end point becomes Ye ≧ Yh, the information of the vector is deleted from the AET. For example, in the case of the Y line as shown in FIG. 5C, the information on the vectors A and B is registered in the AET as shown in Table 3.

(Step 7): The coordinate X of the intersection is calculated from the coordinate value Yh of the Y line and the vector information registered in the AET, and the value of X is registered in the work table WT. That is, as shown in Table 4, the coordinates XA and XB of the intersections of the Y line and the vectors A and B shown in FIG.
Registered in WT.

(Step 8): The values of X in WT are sorted in ascending order and registered in the sorted work table SWT.
That is, since XA <XB in the example shown in FIG. 5C, the contents of WT shown in Table 4 remain unchanged and Table 5
Is registered in the SWT shown in FIG.

As described above, the preparation for the anti-aliasing processing is completed in the routine up to step 8, and the following steps 9 to 12 are the anti-aliasing processing.

(Step 9): One line (scan line)
Is divided into N sublines, and one pixel is divided into N sublines.
A sub-pixel divided into × N sub-pixels is formed on a working memory (working area in the memory), and the same routine as steps 7 and 8 is performed for each sub-line.
1 if it is on or inside the edge for each subpixel
The filling process of (filling) and 0 (leaving white as it is) outside the edge is repeated N times.

(Step 10): According to one filled sub-pixel of one pixel, the contribution rate of the pixel is calculated. At this time, the number of 1 sub-pixels is (N ×
The uniform averaging method divides by N) to obtain the contribution rate, and the weighted averaging method calculates the contribution rate using a sub-pixel filter described later.

(Step 11): Based on the obtained contribution ratio K, the product of D1 and (1−K) and D2 from the density D1 of the pixel before processing and the density D2 of the group under processing.
The sum of the product of K and K is determined as the density after pixel processing.

(Step 12): The density thus determined is repeatedly written into the frame memory for one page preset for each pixel, and the anti-aliasing processing for one line is completed. .

(Step 13): Yh = Yh-1, that is, the Y line is lowered by one line pitch. (Step 14): It is judged whether or not Yh> Ye min, that is, whether or not the Y line is above the lowest point. If it is above, the process returns to step 6, and if not, the process proceeds to the next.

(Step 15): It is judged whether or not the processing is completed for all the groups, and if not, the process returns to Step 1 (in the case of graphic information input) or Step 2 (in the case of vector information input), If the processing of the group of is completed, it becomes the end.

FIG. 6 shows the figure shown in FIG.
FIG. 9 is a diagram showing an example of a state of sub-pixels formed in the working memory when the step 9 is completed by dividing the pixel into 3 × 3 sub-pixels and performing the anti-aliasing process, which is filled with each sub-pixel. Is indicated by a circle, and the uniform averaging method for each pixel, that is, the contribution rate calculated by dividing the number of subpixels of 1 by the number 9 of subpixels of the pixel is added to the lower side.

FIG. 7 is an enlarged view showing an example of how the expression of 7 gradations from density 0 (white) to density 6 (black solid) differs depending on the modulation method. (B) is L
An example of PWM (pulse width modulation) in BP, an example of PM (power modulation) in LBP and a CRT in FIG. 7C, and an example of PM in a thermal printer in FIG.

FIG. 7A shows an example of normal PWM in which phase control is not performed, and the dot width increases from the left end of the pixel to the right as the density increases. In (B) of the figure, the phase control is performed so that the width of the dot expands from the center to both sides.
It is an example of WM. (C) of the figure is an example of PM, LB
What is scanned at high speed, such as P and CRT, tends to have a horizontally long ellipse instead of a circle.

FIG. 7D shows an example in which PM is carried out by a sublimation-type or fusion-type thermal printer having a one-line head. If the power waveform of PM is bad, it becomes as shown in FIG. 7C. If the waveform is good, it becomes round. However, since the paper is fed vertically, it becomes a vertically long ellipse as shown. Further, although not shown, LCM (liquid crystal matrix)
In some display devices, the dot size does not change even with PM, and the brightness changes almost uniformly.

FIG. 8 shows a normal PWM as shown in FIG. 5A by LBP for a graphic having pixels with uniform density due to symmetrical edges on both sides (edges) where black solid pixels are lined up. It is an enlarged view showing an example in the case of performing.

In such a case, since the contribution ratios obtained by the simple uniform averaging method are the same, as shown in the figure, the left edge pixel is separated from the dot, and the right edge pixel is connected. Although the density is the same, the left side seems to have smaller density. In this example, the problem can be solved by controlling the phase as shown in FIG. 7B, but it cannot always be said that the PWM in which the phase is controlled does not eliminate the problem.

FIG. 9 is a diagram showing an example of a subpixel filter suitable for an output device using each of the modulation methods shown in FIG. 7, and shows a filter when one pixel is divided into 6 × 6 subpixels. Shows. The subpixel filters shown in FIGS. 9A to 9D are respectively shown in FIGS.
This is for correcting the dot characteristics by the modulation method shown in (D).

The anti-aliasing process used for these subpixel filters is a kind of weighted averaging method, and is a product of products obtained by multiplying the subpixel value 1 or 0 at the corresponding position by the subpixel filter value. The contribution ratio is obtained by dividing the total sum by the total sum of the values of the sub-pixel filters. When there is no unevenness as in a display device using LCM, calculation using a subpixel filter with all 1s, that is, a uniform averaging method may be used.

For example, if the sub-pixel filter shown in FIG. 9A is combined with the normal PWM LBP without phase control shown in FIG. 7A, the left edge shown in FIG. The sub-pixels of the partial pixels are concentrated on the right side in FIG. 9A, and the sub-pixels of the edge pixels on the right side are concentrated on the left side. Will increase. Therefore, the width of the dot on the left side shown in FIG. 8 becomes wider than that on the right side, and the feeling of low density is corrected.

As described above, when the anti-aliasing processing is performed by using the sub-pixel filter suitable for the characteristics, that is, the type of the output device, a high quality image is obtained. However, conversely selecting and using an unsuitable sub-pixel filter gives worse results than using the simple uniform averaging method. Therefore, it is extremely important that the sub-pixel filter is selected correctly.

FIG. 1 is a circuit diagram showing the configuration of an image processing apparatus according to the first embodiment of the present invention. The image processing apparatus 1 shown in FIG. 1 stores a CPU 2 which is an anti-aliasing processing means and a filter selection means, a ROM 3 which stores programs used by the CPU 2 and various data and tables, and is also used as a working memory. RAM
4, a frame memory 5 that is a RAM for storing image data to be output to an output device, a non-volatile RAM 6 that stores a plurality of subpixel filters, and a host I
/ F7 and the output switching unit 8.

The image processing apparatus 1 is connected to a host machine 10 via a host I / F (interface) 7, and a plurality of output devices 20, 20a,
20b ... Are selectively connected.

The output device 20 comprises an output main body 21 and an I / F 22 for connecting to the image processing device 1. Since the output device 20a and the subsequent components have the same structure as the output device 20, the internal structure is not shown. is doing.

The output switching section 8 includes output devices 20, 2 respectively.
0a ... Has a plurality of output terminals (not shown) connected by a cable, and by switching the output terminals according to a command from the CPU 2, the connected output device can be switched. When the host machine 10 specifies the output device, C
The command is transmitted to the output switching unit 8 via PU2.

When the CPU 2 is initialized after the power is turned on,
The output devices 20, 20a ... Are connected in order via the output switching unit 8 and the result of detecting and identifying the type is stored in the RAM 4. Therefore, whichever output device is connected, the optimum subpixel filter for the output device can be immediately selected from the many subpixel filters stored in the nonvolatile RAM 6 and stored in the RAM 4.

Whenever the CPU 2 switches and connects the output devices, the CPU 2 outputs from the host machine 10 if the switching is a command from the host machine 10, or from the connected output device if the switching is based on the command of the CPU 2 itself. It is also possible to input information about the type of output device connected to each and select the optimum sub-pixel filter according to the input information.

Alternatively, in a case similar to the above, CP
U2 is from the host machine 10 or the connected output device,
Instead of the information on the type of the output device, information on the type of the sub-pixel filter most suitable for the output device may be input, and the sub-pixel filter may be selected according to the input information.

In any case, the vector information of the image is input from the host machine 10 via the host I / F 7 at a time or in groups, and the anti-aliasing process is performed using the sub-pixel filter transferred to the RAM 4. Since the image data (density) data formed in the frame memory 5 is executed and output to the output main body via the I / F (interface) of the output device connected to the output switching unit 8, and is displayed or printed. , Always get the best image.

FIG. 2 is a circuit diagram showing the structure of an image processing apparatus according to the second embodiment of the present invention. The image processing apparatus 1a shown in FIG. 2 is different from the image processing apparatus 1 of the first embodiment shown in FIG. 1 in that the non-volatile memory 6 storing a plurality of subpixel filters is eliminated. Others are exactly the same, so the same parts are denoted by the same reference numerals and description thereof is omitted.

In this embodiment, the image processing apparatus 1a alone does not have a sub-pixel filter, so there is no room for selection. However, a sub-pixel filter that is most suitable for the type depending on the type of output device to which the host machine 10 is connected. From among a plurality of sub-pixel filters stored in the disk device 11 attached to the host machine 10, C
The PU 2 inputs the data itself of the subpixel filter selected by the host machine 10 and stores it in the RAM 4.

After that, the CPU 2 performs the anti-aliasing process by the sub-Vixel filter stored in the RAM 4, so that the same effect as that of the first embodiment can be obtained. Further, since it is not necessary to store a large number of subpixel filters, the non-volatile RAM 6 is unnecessary, and if only one subpixel filter is used, it can be easily stored in the RAM 4.

FIG. 3 is a circuit diagram showing the structure of an image processing apparatus according to the third embodiment of the present invention. The configuration of the image processing apparatus 1b shown in FIG. 3 is exactly the same as that of the image processing apparatus 1a of the second embodiment shown in FIG. 2, except that the CPU 2 replaces the subpixel filter data with the host machine 10. The difference is that input is made from the connected output device itself.

Therefore, the output devices 23, 23a, 23b
In the configuration of ..., In addition to the output devices 20, 20a, 20b connected to the first and second embodiments, the data of the sub-pixel filter optimal for the characteristics or type of each output device is stored in a nonvolatile manner. A memory 24, which is a memory RAM or the like, is provided.

This third embodiment is superior to the first and second embodiments in that the image processing apparatus 1 or the host machine 1 is
When 0 has a sub-pixel filter, many types must be prepared, but when each output device has 0, one type or several types according to the number of sub-pixels are sufficient.

Further, the shape of the dots according to the modulation method shown in FIG. 5 is not fixed, but varies depending on the output device, and tends to change with temperature or with time. Therefore, if each output device 23, 23a, 23b ... Has a sub-pixel filter, even if the dot shape changes, the sub-pixel filter can be immediately corrected according to the change. Machine 1
It is practically impossible to correct the contents of the disk device 11 of 0 because of the relationship with other output devices.

Therefore, not only is maintenance easy, but by updating the built-in sub-pixel filter according to the change in the characteristics of the output device, the highest quality display or printing can always be obtained as the output device. Further, even a new type output device in which the image processing device or the host machine does not have a subpixel filter suitable for it can be easily exchanged and connected.

[0072]

[Table 1]

[0073]

[Table 2]

[0074]

[Table 3]

[0075]

[Table 4]

[0076]

[Table 5]

[0077]

As described above, the image processing apparatus according to the present invention always uses the optimum sub-pixel filter according to the connected output device without imposing any burden on the operator. An image is obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a configuration of a first embodiment of an image processing apparatus according to the present invention.

FIG. 2 is a circuit diagram showing a configuration of a second embodiment of the image processing apparatus.

FIG. 3 is a circuit diagram showing a configuration of a third embodiment of the image processing apparatus.

FIG. 4 is a flowchart showing an example of an image processing routine.

5 is a diagram showing an example of a graphic processed by the routine shown in FIG.

FIG. 6 is a diagram showing an example of a state of sub-pixels formed by anti-aliasing the figure shown in FIG.

FIG. 7 is an enlarged view showing an example of a difference in gradation expression depending on a modulation method.

FIG. 8 is an enlarged view showing an example of a difference in expression between left and right edge pixels of a figure.

FIG. 9 is a diagram showing an example of a sub-pixel filter used for anti-aliasing processing.

[Explanation of symbols]

1, 1a, 1b: Image processing device 2: CPU (anti-aliasing processing means, filter selection means, means for inputting data of sub-pixel filter) 5: Frame memory 6: Non-volatile RAM 8: Output switching unit 10: Host machine 20, 20a ..., 23, 23a ...: Output device

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G09G 5/20 9471-5G 9365-5L G06F 15/72 355 K

Claims (5)

[Claims] 1. An image processing apparatus for processing vector data of an image input from a host machine to form image data, outputting the image data to a connected output device to display or print the image, An anti-aliasing processing means for performing anti-aliasing processing based on vector data, and a plurality of sub-pixel filters having mutually different characteristics used for obtaining the contribution rate of the edge pixel when the processing means performs the anti-aliasing processing, A filter selecting means for selecting one of the plurality of sub-pixel filters to be used by the anti-aliasing processing means according to the type of the output device connected. Image processing device. 2. The image processing apparatus according to claim 1, wherein the filter selection unit detects and identifies the type of the output device connected thereto, and the sub-pixels according to the identified type of the output device. An image processing apparatus, comprising means for selecting a filter to be used by the anti-aliasing processing means. 3. The image processing apparatus according to claim 1, wherein the filter selection unit inputs information on the type of the output device from the host machine or a connected output device, and according to the input information. An image processing apparatus, comprising means for selecting the sub-pixel filter for use by the anti-aliasing processing means. 4. The image processing apparatus according to claim 1, wherein the filter selection unit inputs information on a type of sub-pixel filter suitable for the type of the output device from the host machine or a connected output device. An image processing apparatus, which is means for selecting the sub-pixel filter according to the input information and causing the anti-aliasing processing means to use the sub-pixel filter. 5. An image processing device for processing vector data of an image input from a host machine to form image data, outputting the image data to a connected output device to display or print the image, The anti-aliasing processing means for performing anti-aliasing processing based on vector data, and the sub-pixel filter data used by the processing means for obtaining the contribution rate of the edge portion pixel when performing the anti-aliasing processing are stored in the host machine or An image processing apparatus, comprising means for inputting from a connected output device to be used by the anti-aliasing processing means.