JPH10215410A - Composite drawing data generation method, and composite drawing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fast give an edge of the prescribed width to a drawn image and also to fast generate the α data on the edge by generating previously the αdata on the drawn image main body data and then generating an edge and the α data on the edge part. SOLUTION: A CPU 101 draws a color image as a black/white image with a RAM 103 used as its work area, calculates an area ratio of a substantial drawing area for each pixel dot, i.e., a minimum drawing unit area, and generates the α data on the drawn image main body. Then, the edge part dots of the drawn image main body are searched and a frame is drawn around every detected edge part dot and separately from the dot by the designated edge width. The inside of the frame is painted out with α=1. The color data on a drawn image having an edge where the drawn image main body is composed with the edge are written in a VRAM 13 and a VRAM 14 by composing an α plane of the drawn image main body with two α planes of the edge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the generation of synthetic drawing data used for generating drawing images of characters, figures, symbols, etc., which are displayed by being synthesized with a display image based on a video signal such as a television signal. The present invention relates to a drawing method and apparatus, and a combined drawing apparatus.

[0002]

2. Description of the Related Art For example, when a drawn image such as a character or a figure is combined with a moving image such as a title displayed on a display screen of a television program or a subtitle of a movie, a so-called video terrorist or titler is used. A device for generating combined drawing data is used.

In such an apparatus for generating composite drawing data, for example, FIG.
As shown in FIG. 4, a drawing image (FIG. 14A) such as a character or a figure to be synthesized with a base moving image (FIG. 14B) formed by a video signal is generated. The drawn image is generated using, for example, a font included in the synthetic drawing data generating device.

[0004] The drawing image generated by this font is
Even if it has a high resolution, when it is displayed by being synthesized with a video signal, a drawn image is formed by a finite number of dots (pixels) constituting a screen. The edge portion may be “jagged,” and the drawn image may have a strange feeling.

[0005] Therefore, a so-called anti-aliasing technique is used to generate a drawn image in order to smooth the edges of the drawn image to be synthesized and to generate a high-quality drawn image. This method is to increase the apparent resolution by using an intermediate value for the ratio of synthesizing a video signal composed of certain finite dots. With this anti-aliasing method, it is possible to suppress the occurrence of “jaggies” at the edges of the characters.

[0006] In the case of a commercial (broadcasting) synthetic drawing data generating apparatus, most synthesized characters are synthesized with smooth characters by the anti-aliasing technique. In recent years, this anti-aliasing method has been used even for consumer equipment in order to draw higher quality images.

When the anti-aliasing method is used, in addition to the drawn image data of drawn characters, figures, symbols, and the like (called objects), α data which is information mainly indicating the composition ratio of the object and the background image is used. Generate contour data called.

In order to generate the contour data (hereinafter referred to as α data), a color drawing image of an object is divided into N pieces (N is 2 or more) for each drawing minimum unit area (corresponding to a pixel dot area). It is determined whether each of the divided areas is an area that is included in the object and actually performs drawing (this is called a substantial drawing area in this specification). Then, with respect to the contour portion of the object, the area ratio of the substantial drawing area to the minimum drawing unit area is calculated based on the number of the minimum drawing unit areas in the divided area where the drawing is performed, and is set as α data.

In practice, since the minimum drawing unit area corresponds to an image dot, the system executes processing in image dot units. Therefore, the color drawing image is drawn in an area enlarged to be N times the minimum drawing unit area so that the divided area has the size of the minimum drawing unit area. For each N-times unit area, the area ratio of the substantial drawing area for each of the minimum drawing unit areas is obtained, and the α data is obtained.

When the base video image and the drawing image such as characters and figures are synthesized, the outline portion of the drawing image is converted to the base image at a synthesis ratio determined by the α data obtained as described above. , The jaggedness at the edges of the drawn image can be suppressed, the apparent resolution can be increased, and the drawn image such as characters and figures can be generated as a smooth, high-quality image.

By the way, a device for generating composite drawing data such as a titler has a function of applying various modifications to characters and figures generated by drawing. As one of the modification functions, there is a function of giving an edge of a predetermined width around the generated drawn image. For example, as shown in FIG. 15, an edge EG having a constant width is provided around a portion of the drawn image body LT such as a character body.

When a character drawing image is superimposed on a background image by superimposition, an edge is required in most scenes. This is because the color and brightness of the underlying image are changing in real time, so it is necessary to provide a contrast between the character body and the edge so that the title character can be clearly recognized in any image. It is.

The drawing image data to which the edge EG has been added and the α data of the edge have conventionally been generated as follows.

First, the drawn image body LT is drawn in the enlarged area as shown in FIG. 16 in the same manner as when the α data is generated. Then, the drawn image main body LT, which is the inner part shown in FIG. 16, is moved up, down, left, and right by an edge width to be provided, and an edge is created based on the movement locus. That is, all of the dots constituting the drawn image body LT are copied up, down, left, and right by the width of the edge to be provided. Then, the copied image is combined with respect to all pixels, and as a part other than the drawn image main body LT, FIG.
6, an edge EG is obtained. At this time, the color of the generated edge EG is set to the color specified by the operator.

Next, as described above, the area ratio of each of the enlarged unit regions is determined to obtain α data for the drawn image data to which the edge has been added.

[0016]

As described above, in a conventional synthetic drawing data generating apparatus, when an edge is generated, a color drawing image is drawn in the above-described enlarged area on a memory, and the color drawing image is drawn. Edges are generated by shifting up, down, left, and right for each minimum unit area (dot) of the color drawing image on the enlarged area. Then, α data is generated for the generated edge.

For example, red (R) for forming a color image,
When each of the color information of green (G) and blue (B) is represented by 8 bits, each dot of the enlarged area where the drawn image is formed is composed of 24 bits of color information.

Therefore, even when the color dots are not shifted up, down, left and right, a plurality of bits must be handled. As described above, when a drawn image is treated as a color image, the amount of information increases, so that the number of dots that can be processed at one time is small, the number of loops in software processing increases, and an edge is generated. Cannot be performed at high speed.

Also, in the processing for obtaining the area ratio when generating the α data, since color data is used, it is necessary to similarly handle a plurality of bits per dot, so that the processing speed cannot be increased.

Further, in the case of the above-described conventional example, in order to generate α data of the added edge, in the enlarged area,
After forming an edge by moving and copying all the color data up, down, left, and right, α data must be generated. As described above, moving the color data up, down, left, and right in the enlarged area increases the memory size to be accessed,
The number of times of access also increases. For this reason, the processing speed also becomes a significant problem in this respect.

Instead of using color drawing image data to generate edges, it is also conceivable to convert this into black and white data, draw the drawing image in an enlarged area, and use the bitmap of the black and white drawing image as the drawing result. Can be According to this, one pixel is one bit, and the number of dots to be processed at once increases.
High-speed processing can be performed as compared with the case where color data is handled as described above.

However, when an edge is created, even if it is black and white bitmap data, in addition to memory copying,
The bit shift operation must be performed by the width of the edge to be created, which is still a problem in terms of processing speed.

For example, when an image is drawn in an enlarged area of 16.times.16 times to generate .alpha. Data, an edge having a size of the original size and a width of 2 dots is provided. In the enlarged area, 16 × 2 =
It is necessary to perform a process of superimposing dots while shifting the dots within a range of 32 dots, and the processing speed becomes a problem.

As described above, in the conventional edge generation method and its α data generation method, since the drawn image body drawn in the enlarged area is drawn many times, an extremely wide memory area is accessed. And there was a major problem in terms of processing speed.

In view of the above, the present invention provides a high-speed processing for providing an edge having a predetermined width to a drawn image such as a character, figure, or symbol to be synthesized on a display screen and generating α data of the edge. It is an object of the present invention to provide a method and an apparatus for generating composite drawing data that can be used.

[0026]

In order to solve the above-mentioned problems, a method of generating composite drawing data according to the present invention generates α data for drawn image main data in advance and uses the α data of the drawn image main body. , And generation of α data of the edge portion. That is, in the method for generating composite drawing data according to the first aspect of the present invention, the color drawing image data and the color drawing image are combined with each other to display a color drawing image such as a character or a figure on a display image. A method for generating composite drawing data including outline data used for synthesizing a display image, wherein an edge of the color drawing image is detected from the outline data, and α of the edge drawing image data is detected. By copying data around the data, α data for an edge having a predetermined width generated around the color drawing image is generated.

According to a second aspect of the present invention, there is provided a method of generating synthetic drawing data according to the first aspect, wherein the drawing image data of another edge around the drawing image data of the edge is referred to and the other drawing image data around the edge is referred to. The peripheral position of copying the α data of the drawn image data of the own edge is changed according to the position of the drawn image data of the edge with respect to the drawn image data of the own edge.

In the method for generating composite drawing data according to the first aspect of the present invention, the data of the end of the original drawn image is detected by using the α data of the drawn image body which has already been created, and the end of the data is detected. The α data of the generated edge is generated by copying only the α data of the copy to the periphery. That is, a drawn image is drawn in an enlarged area as in the related art, the entire drawn image is moved up, down, left, and right in the enlarged area to generate an edge, and α data of an edge portion is generated from the generated drawn image of the enlarged area. Since it is not generated, the size of the memory to be accessed is reduced, and high speed can be realized.

Particularly, in the case of the invention described in claim 2,
By referring to the drawn image data of the other edges around the drawn image data of the edge, it is possible to determine the memory area in which the α data for the drawn image data of the own edge must be copied, and accordingly, Within a limited range, α data for a data portion constituting an edge can be copied, and higher-speed processing can be realized.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a method for generating combined drawing data and a combined drawing apparatus according to the present invention will be described with reference to the drawings.

In the embodiment described below, the composite drawing apparatus can perform two types of anti-aliasing. One is so-called video anti-aliasing, which displays a smooth drawn image by using the combination ratio of a plane of a drawn image such as a character or a figure and a plane of a background such as a moving image to be synthesized as α data. Is what you do.

The other anti-aliasing is so-called CG anti-aliasing which is performed in a character plane. For example, a drawing image of a character or the like and an edge (edge) attached thereto, a drawing image of a character or the like are provided. The boundary of the overlapped part is determined not by the combination ratio but by the color of the part according to the α data. That is, the portion between the character drawing image and the edge (edge) is represented by an intermediate color corresponding to the α data between the color of the character body and the color of the edge portion.
In addition, the boundary between drawn images such as overlapping characters is drawn in an intermediate color between the two according to the α data, so that a smooth drawn image is displayed.

Therefore, in the composite drawing apparatus according to the embodiment described below, α data is used for two types of anti-aliasing, that is, video anti-aliasing and CG anti-aliasing.

FIG. 1 shows a composite drawing apparatus 1 according to this embodiment.
It is a block diagram for explaining. The composite drawing device 1 includes a part of a composite drawing data generation device.

The synthetic drawing apparatus 1 in the example of FIG. 1 transfers a drawing data composed of a synthetic drawing data generating section 100 composed of a computer, a graphic accelerator 12, and video RAMs (hereinafter, referred to as VRAMs) 13, 14, and 15. A buffer section 11, a digital video mixer 21 for synthesizing the generated color drawing image data and input video image data described later, and a key signal controller 2
2, an input terminal 31 for an external video signal, an A / D converter 32, D / A converters 33 and 34, and output terminals 41 and 4
2 and 43.

As shown in FIG. 1, the composite drawing data generation unit 100 includes a CPU 101, a ROM 102, a RAM 10
3, VRAM 104, display controller 105
, And are connected via a system bus 109. The display 2 is connected to the display controller 105. The keyboard 3 and the mouse 4 that receive drawing input information from the user are connected to the system bus 1 via the I / O port 111.
09.

The ROM 102 stores various information used in the composite drawing apparatus 1 of this embodiment, such as font data such as characters, figures, and symbols, and programs. The RAM 103 is used as a work area for various processes, and the VRAM 104 is a display memory used for displaying the generated drawn image.

Then, the composite drawing data generation unit 100
In accordance with drawing input information from a user input via the keyboard 3 or the mouse 4, a color drawing image such as a character or a figure to be synthesized with a color video signal input through the input terminal 31 is prepared in advance in, for example, the ROM 102. Is drawn using the existing font rasterizer and graphic drawing routine.

In this case, the color drawing image corresponding to the drawing input from the user is drawn in the VRAM 104. VRA
The color drawing image drawn on the M104 is read by the display controller 105 in accordance with an instruction from the CPU 101, and displayed on the display 2.

When the drawing image displayed on the display 2 is the drawing image intended by the user, the user performs a confirmation input via the keyboard 3 or the mouse 4. This confirmation input is, for example, pressing a preview button key on a keyboard or selecting a preview icon displayed on the screen of the display 2 with a mouse.

At this time, if the color drawing image displayed on the display 2 is not the one intended by the user, the user inputs a new drawing instruction, and the color corresponding to the new drawing instruction is input. A drawn image can be drawn and displayed on the display 2.

When the user performs a confirmation input, the CP
U101 detects this, uses the RAM 103 as a work area, and draws a color drawing image as a black-and-white drawing image in this example, as will be described in detail later, and draws a minimum unit area of the black-and-white drawing image. Then, the area ratio of the substantial drawing area is obtained for each pixel dot, and α data is generated.
This is to increase the processing speed of generating α data for the drawn image body.

At this time, in this embodiment, when there is an instruction input for giving an edge including an instruction of a display color and a width to a character body as a drawn image at the time of drawing input, as described later. , Α generated for the character body
An edge is generated using the data, and α data thereof is generated.

Then, the CPU 101 sets the VRAM 104
Is supplied to the graphic accelerator 12 based on three color signals of red (R), green (G), and blue (B) on the basis of the color drawing image drawn on the 12

In this embodiment, each of the R, G and B primary color signals is represented by, for example, 8 bits. The α data has a bit number according to the precision of the anti-aliasing.

The graphic accelerator 12 has R,
A luminance signal (Y) and a color difference signal (U / V) are generated based on the G and B color signals. In this case, the luminance signal (Y) and the color difference signal (U / V) are each represented by, for example, 8 bits.

Then, the graphic accelerator 12
Represents the generated luminance signal (Y) and color difference signal (U / V) as V
Write to RAM13, VRAM14. Further, the graphic accelerator 12 converts the transferred α data into V
Write to RAM15.

VRAM13, VRAM14, VRAM1
The luminance signal, the color difference signal, and the α data which form the color drawing image for one screen written in 5 are read out and supplied to the digital video mixer 21.

The digital video mixer 21 has an input terminal 3
A video signal input through the A / D converter 1 and converted to a digital signal by the A / D converter 32 is converted into a color drawing image formed by a luminance signal (Y) and a color difference signal (U / V) read from the VRAMs 13 and 14. Are synthesized by performing the above-described video anti-aliasing based on the α data read from the VRAM 15. The video signal synthesized by the anti-aliasing and the color drawing image is converted into an analog signal by a D / A converter 21a incorporated in the digital video mixer 21, and is output via an output terminal 43, and is output to a monitor receiver. And other equipment.

Further, the composite drawing apparatus 1 of this embodiment
In consideration of the fact that a video signal and a color drawing image are synthesized by performing a video unchained operation according to the α data obtained by the synthesizing and drawing device 1 using a switcher or the like provided outside, a luminance signal (Y ), The drawn image data formed by the color difference signal (U / V) is supplied to the D / A converter 34, converted into an analog signal, and output to the outside via the output terminal 42. Has been.

In this case, α written in the VRAM 15
The data is read from the VRAM 15 and supplied to the key signal controller 16, where the data is converted into a key signal used for synthesizing the color drawing image with the video signal, and output to the outside via the output terminal 41. You.

Thus, as shown in FIG. 2, the switcher 5 has a function of synthesizing a color drawing image with a video signal in accordance with a key signal. The output key signal is supplied through the input terminal 51 of the switcher 5. The drawing data output through the output terminal 42 of the combined drawing device 1 is supplied through the input terminal 52 of the switcher 5.

Then, the video signal input from the video signal input terminal 53 of the switcher 5, the drawn image data, and the key signal are supplied to the synthesizing circuit 54 of the switcher 5. The synthesizing circuit 54 controls the synthesizing ratio of the color drawing image formed by the drawing data according to the key signal from the input terminal 51, and converts the video signal supplied from the input terminal 53 into the drawing signal from the input terminal 52. A color drawing image formed by the data is synthesized by video anti-aliasing.

The color video signal synthesized from the color drawing image from the synthesizing circuit 54 is supplied to the output terminal 5 of the switcher 5.
5 and supplied to a monitor receiver or the like.

Next, a description will be given of a process of obtaining α data used for edge addition and anti-aliasing of an edge portion, which is performed in the composite drawing apparatus 1 according to this embodiment. The composite drawing apparatus 1 of this embodiment can quickly obtain α data used for anti-aliasing.

In this example, when a confirmation instruction such as operating a preview button is given to a drawn image for which an edge is given, alpha data is generated for the drawn image body. The created one is not the one of the enlarged area, but the α data of each dot of the original drawn image.

Next, the dot position of the edge to be created is determined from the α data of each dot of the original drawn image. As will be described in detail later, by calculating the dot position of the edge, the α data of the edge is directly generated. The color of the generated edge dot is set to the color set at the time of drawing input, and the dot at the portion between the edge portion and the drawn image body is, as described later in detail, Using the data, a display color is determined by performing CG anti-aliasing to make the color intermediate between the two colors. The drawing image data to which the edge is added in this way is
VRAM 13 through graphic accelerator 12,
14 is written.

The generated α data of the edge and the α data of the drawn image body are written in the VRAM 15. If the transmittance of the drawing image body and the generated edge is set with respect to the background at the time of drawing input, the final α data is generated in consideration of the value, and the graphic accelerator 12 is generated. Through VR
It is written to AM15.

First, a description will be given of the process of generating α data for the drawn image body. In the combined drawing apparatus 1 of this embodiment, the combined drawing data generation unit 100 can quickly generate α data used for anti-aliasing.

As described above, when the CPU 101 detects, for example, that the preview button key on the keyboard has been pressed or that the preview icon displayed on the screen of the display 2 has been selected by the mouse, the CPU 101 reads the ROM.
A color drawing image is drawn as a black-and-white image by using an existing drawing routine for a black-and-white bitmap prepared in advance in 102. In this case, all the dots in the drawn image that are colored are represented in black, and the portions of the drawn image where there are no dots are white.

In this case, the CPU 101 uses the drawing data for forming the color drawing image as black and white data, and draws a drawing image, for example, which is twice as long and wide in the RAM 103 in this embodiment. The magnification of the drawn image is determined according to the accuracy of the anti-aliasing.

As described above, the CPU 101
3, an enlarged area is formed as a black and white bitmap for drawing an enlarged black and white image, and a black and white drawing image is drawn using this enlarged area as a so-called canvas.

The black-and-white bit map indicates whether one pixel dot (hereinafter, simply referred to as a dot) is white or black (whether or not it is colored), and each dot corresponds to one bit. It is. Therefore, in the black and white bitmap, one dot can be represented by one bit, and
Since one dot is one byte, the efficiency of use of the memory is good, and the processing efficiency of the CPU 101 is also good.

For example, when the drawing input information from the user indicates that the character “A” is to be drawn, for example, the CPU 101 stores in the RAM 103 a monochrome double-sized image as shown in FIG. Draw a drawing image.

In this case, since the drawn black-and-white image is enlarged both vertically and horizontally, as shown in FIG. 3B which is a partially enlarged view of FIG. 3A, one dot of the original original drawn image is , Are drawn in a unit area composed of four dots, two dots each in the vertical and horizontal directions.

The black-and-white drawing image is drawn in an enlarged manner as described above, and the area ratio of the substantial drawing area to each unit area constituting the expanded area in which the drawn image is drawn is obtained, thereby obtaining the original size drawing. The α data can be generated by calculating the area ratio for each dot as the minimum drawing area of the image.

For example, if the number of dots (substantial drawing area) actually used to form a black-and-white drawn image in a unit area of 4 dots of 2 dots vertically and horizontally is 1 dot, The area ratio, which is the ratio of the drawn image to the unit region formed by 4 dots, is 25% (α
= 0.25).

Similarly, when the number of dots used to form a drawn image is 2 in the unit area formed by the four dots, the area ratio is 50% (α =
0.5), when the number of used dots is 3, the area ratio is 75% (α = 0.75), and when the number of used dots is 4, the area ratio is 100% (α). = 1)
Can be determined.

As described above, the area ratio of the substantial drawing area to the unit area composed of 4 dots each of 2 dots vertically and horizontally is determined by the area ratio of 1 dot as the minimum drawing unit area of the original drawn image. Become. Then, an area ratio is obtained for each of the unit areas of the enlarged area on which the enlarged image is drawn, and α data can be generated based on the obtained area ratios.

In this case, the enlarged image drawn in the enlarged area formed in the RAM 103 is, as described above,
Since it is rendered using black and white data, it has no information about colors. Therefore, the CPU 101 enlarges and draws the drawn image in the enlarged area formed in the RAM 103, and according to the number of dots used to form the drawn image for each unit area formed of 4 dots, The α ratio can be generated by determining the area ratio.

Therefore, as shown in FIG. 3B, the α data for each dot (minimum drawing unit area) forming the original drawn image using the drawn image enlarged twice in length and width is obtained as shown in FIG. 4A.
Can be obtained as shown in FIG. In this case, a dot having a large α data has a large portion of a drawn image, and a dot having a small α data has a small drawing portion.

Generally, as described above, in the case of video anti-aliasing, as shown in FIG. 4B, when the value of α data is large, a large portion of the drawn image is displayed, and when the value of α data is small, the background of the background is displayed. It takes the form that many parts are displayed.

In this embodiment, only the drawn image is displayed on the dot having the α data of 100% (α = 1), and the dot having the α data of 0% (α = 0) remains as the background. Becomes For other dots, the composition ratio of the drawn image is adjusted in accordance with the α data, and as shown in FIG. 4C, the anti-aliased high-quality drawn image from which the jaggedness at the edges of the drawn image has been removed. Can be generated.

Next, with reference to the flowchart shown in FIG. 5, the generation processing of α data in the composite drawing data generation unit 100 will be described.

As described above, a color drawing image corresponding to the drawing input information is formed in the VRAM 104 by the user, and after this is displayed on the display 2, confirmation input such as pressing of a preview button key is performed. Then, the CPU 101 executes the α data generation processing shown in FIG.

First, the CPU 101 draws a target drawn image (object) in black and white at a magnification corresponding to the anti-aliasing precision (step 201). This first
In the embodiment, the drawn image enlarged twice in length and width by the processing in step 201 is stored in the RAM 103.
A black and white image is drawn in an enlarged area formed as a black and white bitmap.

Next, the CPU 101 reads data of the unit area in the enlarged area formed as a black and white bitmap (step 202), and counts the number of black dots in the unit area (step 203).

Then, based on the number of black dots in the unit area obtained by the processing in step 203, the area ratio indicating the ratio of the drawn image to the unit area is obtained, and α data is generated (step 204).

Next, it is determined whether or not the area ratio has been calculated for all the unit regions constituting the enlarged and drawn image (step 205). This determination process is a process of determining whether α data has been obtained for all the dots in the drawing area where the drawn image is formed, when the drawn image of the original size is drawn.

If it is determined in step 205 that α data has not been obtained for all the unit areas, the data reading position is positioned in the next unit area, and the processing from step 202 is repeated.

In the determination processing of step 205, α is set for all the unit areas constituting the enlarged area.
When it is determined that data has been obtained, the process of generating α data for all the dots constituting the drawn image is terminated.

As described above, in the combined drawing apparatus 1 of this embodiment, the drawn image is drawn in an enlarged area as a monochrome bitmap in which one dot can correspond to one bit, and the drawn image is drawn. By calculating the area ratio for each unit region constituting the region, α data is generated for each dot in the drawing region where the original drawn image is formed.

As described above, by using a black and white bitmap in which one dot can correspond to one bit, a drawn image is drawn as a conventional color image, and each of the drawing areas forming the drawn image is drawn. Compared to the case where α data is generated in a state where the amount of information accompanied by color information for each dot is large,
The amount of information to be processed is very small. This gives α
Data can be generated at high speed, anti-aliasing can be performed quickly, and a high-quality drawn image can be combined with a video signal.

When generating the α data, as described above, paying attention to drawing an enlarged drawn image on a black-and-white bitmap, a case where a drawn image is formed on an enlarged area (black-and-white bitmap) By preparing in advance a conversion table between the black and white drawing pattern and the α data, α data can be generated even faster.

Next, the generation of an edge at the designated width and display color and the generation of the α data on the basis of the α data of the original drawn image body generated as described above will be described. Generation of this edge and its α
The data is not generated in the enlarged area when calculating the α data, but is generated based on the α data of the original drawn image data.

When an edge is added to a drawn image body such as a character, the edge portion to be added is obtained by thickening the end portion of the drawn image body by a specified width. Therefore, in this embodiment, an edge is generated by detecting an "edge dot" of the drawn image body and generating an edge only for the edge dot.

In this embodiment, the dot at the end of the drawn image body is searched from the α data. In other words, the α data of the drawn image body is “
α = 1, and in a dot other than the drawn image, α = 0
It is. Then, the α data of the dot at the end in the drawn image body is always 0 <α <1. ". From this, when one of the following two conditions is satisfied, the dot is detected as a dot at the end of the drawn image body.

(1) When the value of the α data of the drawn image body is 0 <
When α <1. (2) Even when α of the dots in the drawn image body is α = 1, when at least one dot of α = 1 exists among the surrounding eight dots.

The detection of the dot at the end is performed by, for example, scanning rightward from the upper left dot of the drawn image main body, moving to the right end, moving to the left end of the next line, and performing scanning in the same manner. Then, while scanning as described above, the following processing is performed on each of the detected dots at the end of the drawn image main body to generate an edge and generate α data of the edge.

First, a frame is basically written in a portion around the dot at the end of the drawn image main body and separated by a designated edge width around the dot, excluding the dots belonging to the frame. The values of α data inside the frame are all set to α = 1.

It is assumed that the α data of the dot in the frame portion is equal to the α data of the dot at the end of the main body at the center. However, if a frame has been written by another dot before that and an edge has already been generated, the α data of the edge of the existing frame portion is compared with the α data of the current frame portion, and The larger α data is set as the α data of the dot of the edge constituting the current frame. If the value of the α data of the dot at the end of the drawn image body is α = 1, the α data of the frame is unconditionally converted to α without comparing with the value of the α data of the existing edge. = 1.

For example, when an edge having a width of 3 dots is provided, as shown in FIG. 6A, a 7 × 7 zone is formed around an edge dot D0 which is qualified to form an edge. Area. Then, as shown in FIG. 6B, a frame WE, which is the outermost periphery of the area and is separated from the center dot D0 by an edge width, is specified, and the value of the α data of the frame WE is set to an existing edge (frame). The value of the α data which is larger than the value of the α data of (part) is set. Then, the values of the α data of the 5 × 5 dot portion at the center shown in white in FIG. 6B are all set to α = 1.

By performing the above-described processing only for all the detected dots at the end, dots at the edge and their α data can be generated. For example, the created depiction image is a rectangular point, and its α data is shown in FIG.
A is given as an example, and a case where an edge having a width of 1 is added to this is described. In FIG. 7A, the density of the fill is shown as corresponding to the value of the α data. In this case, it is shown that the value of the α data is smaller as the color is darker.

Therefore, the white portion is α = 1, and the α data of the surrounding solid dots which are dots at the end of the drawn image main body is 0 <α <1.

As described above, by sequentially scanning the α data of each dot from the upper left dot to the right in the right direction, the dot portion of the solid portion in FIG. It is possible to detect the dot position of the part and to detect the α data of the dot at the end.

For all of the detected dots at the end, based on the α data, the dot of the edge and the α data are generated as described with reference to FIG. 6 to obtain the α of the edge shown in FIG. 7B. Data can be obtained.

By combining the α plane of the drawn image body and the α plane of the edge obtained in this way, the drawn image body and the edge are combined. That is, as described above, the color data (drawing dot data) of the generated edge portion is the data of the color specified by the drawing input, but the dot data between the generated edge portion and the drawing image body is used. (This is the dot detected as an edge)
By the CG anti-aliasing described above, α
Using the data (see FIG. 7A), a color intermediate between the color of the designated edge and the color of the drawn image body is used.

As described above, the color data of the drawn image with the edge obtained by combining the drawn image body and the edge is written to the VRAMs 13 and 14 through the graphic accelerator 12.

Further, the generated edge α data (FIG. 7)
B), through the graphic accelerator 12, VR
It is written to AM15. If the transmittance of the background image is specified by the operator at the time of drawing input, the α data of the generated edge is changed to one corresponding to the transmittance, and then the graphic accelerator 1 is changed.
2 is written to the VRAM 15.

The α data of the VRAM 15 is
It is used for video anti-aliasing processing at the time of synthesizing the edged drawn images of the VRAMs 13 and 14 and the external video signal from the A / D converter 32.

The composite drawing data generation unit 100 described above
8 is shown in the flowchart of FIG.

That is, first, in step 301, α data of a drawn image body is generated. Then, the process proceeds to step 302, where scanning for edge generation is started. In this scan, as described above, the drawn image main body is scanned from the upper left to the right, and after scanning to the right end, the scan position is sequentially moved downward.

In the next step 303, it is determined whether or not the dot is an end dot as described above. If it is not a dot at the end, the process proceeds to step 304, moves to the next dot position, and returns to step 303. If it is determined in step 303 that the dot is an end dot, the process proceeds to step 305, and as described above with reference to FIG.
A frame WE is drawn at a position separated by a specified edge width from the center of the detected dot at the end.

In step 306, the values of the α data of the existing edges are compared, and the larger value of α is used as the α data of the dots in the frame portion. Is set to α = 1.

Then, the flow advances to step 307 to determine whether or not the target dot is the last dot in the drawn image main body. If not, the flow advances to step 304 to repeat the above processing.
If it is the last dot, the process proceeds to step 308,
The α plane of the drawn image body and the α plane of the edge,
As described above, combining using CG anti-aliasing,
The drawing image body and the edge are combined. Next, step 309
Then, the synthesized image data with the edge and the α plane of the edge are transferred to the VRAMs 13, 14, and 15 through the graphic accelerator 12.

[Further Example] In the above example, all the dots at the ends of the drawn image body generate a closed frame WE around the periphery thereof at a position separated by the edge width. In order to realize higher-speed processing, in the example described below, the generation of an edge and the generation of its α data are performed in consideration of the situation around the dot at each end.

That is, in general, when a certain dot is at the end of the drawn image main body, there is a very high possibility that the adjacent dot is also a dot at the end of the drawn image main body. Also, as described above, α of the dot at the end of the drawn image body
If the data is α = 1, for example, all the dots in the target area for the edge generation shown in FIG. There is no need to make a comparison. That is, α = 1
This is the maximum value, and there is no more dense α.

Therefore, in this example, the situation around the dot at the end where the generation of the edge and its α data is to be performed is referred to, and unnecessary access is not performed according to the reference result. It is.

For example, as described above, taking the case of scanning in the right direction sequentially from the upper left dot and sequentially scanning in the downward direction, for example, in this case, the dot of the target dot is A flag is prepared for what the dots on one line were and what the dots to the left were. Then, by referring to the flag, useless processing and access are prevented from being performed.

As shown in FIG. 9A, a flag buffer for the same number of dots as the width of the drawn image main body is used to refer to what the dots on one line of the target end dots are like. Prepare BA. This buffer BA stores a flag indicating whether or not there is an end of the drawn image body that is continuous in the vertical direction. When the flag is on, it means that the dot above the target dot was the dot at the end of the drawn image body. Therefore, in this case, since the upper dot is the end of the drawn image body, the process related to edge generation may be performed only on the lower portion of the rectangular area, excluding the portion already completed as edge generation. .

The buffer BA also stores information as to whether or not the value of α data of the dot at the end is α = 1. When α = 1, the processing range of edge generation for the target dot can be further narrowed.

Then, a buffer BB for a one-dot flag may be prepared as shown in FIG. 9B for a flag indicating what the left dot is like.

This buffer BB stores a flag indicating the presence or absence of an end of the drawn image body that is continuous in the left-right direction. When the flag is ON, it means that the dot to the left of the target dot is a dot at the end of the drawn image body. Therefore, in this case, since the left dot is the end of the main part of the drawn image, the processing related to edge generation may be performed only on the right part of the rectangular area excluding the part that has already been completed as the edge generation. .

The buffer BB also stores information as to whether or not the value of the α data of the dot at the end is α = 1. When α = 1, the processing range of edge generation for the target dot can be further narrowed.

FIGS. 10 and 11 show specific examples of what range is to be processed as an edge generation range using the flags of the buffers BA and BB. This figure 1
0 and FIG. 11 show a case where an edge having a width of 3 is added to the drawn image body as shown in FIG.

FIG. 10A shows the target end dot D0.
Above and to the left, there is no end dot for drawing an edge. In this case, in the same manner as shown in FIG. 6B, α dots are set for all the dots included in the surrounding frame WE. Generate data. In other words, the value of the α data of the dots in the surrounding frame WE is compared with the value of the α data of the target end dot D0 and the value of the α data of the existing edge to obtain the larger α value. , 5 in the center
All of the × 5 portions are filled with α = 1.

FIG. 10B shows a case where it is determined by referring to the buffer BA that the dot above the target end dot D0 draws an edge and the value of the α data is α ≠ 1. . In this case, as shown in FIG. 10B, the three sides of the frame WE except the upper side are drawn, and the value of the α data of the dot included in the frame WE is changed to the α of the target end dot D0. The value of the data is compared with the value of the α data of the existing edge to obtain the larger value of α. Then, as shown in FIG. 10B as a white dot frame portion, only the portion on one line from the bottom is filled with α = 1.

FIG. 10C shows a case where it is determined by referring to the buffer BB that the dot to the left of the target end dot D0 draws an edge and the value of the α data is α ≠ 1. . In this case, as shown in FIG. 10C, three sides of the frame WE except the left side are drawn, and the value of the α data of the dot included therein is changed to the α of the target end dot D0. The value of the data is compared with the value of the α data of the existing edge to obtain the larger value of α. Then, as shown as a white dot frame portion in FIG. 10C, only the portion one line left from the right end is filled with α = 1.

FIG. 10D shows that the dot above the target end dot D0 and the left dot draw an edge, and that the value of α data is α ≠ 1 with reference to buffers BA and BB. This is the case when the determination is made. In this case,
As shown in FIG. 10D, two sides of the frame WE except for the upper side and the left side are drawn, and the value of the α data of the dot included in the part is replaced with the target end dot D0.
Is compared with the value of the α data of the existing edge to obtain the larger α value. And inside is Fig. 1.
As shown as a white dot frame portion in 0D, only a portion of one dot diagonally upper left from the dot in the lower right corner is filled with α = 1.

FIG. 11 shows a case where the dot above the target end dot D0 or the left dot is an end dot for drawing an edge, and the value of the α data is α = 1. .

That is, FIG. 11A shows the target end dot D
The dot above 0 draws an edge, and its α
This is a case where it is determined that the data value is α = 1 with reference to the buffer BA. In this case, as shown in FIG. 11A, a part of the lower side of the frame WE is drawn, and the value of the α data of the dot included in the frame WE is replaced with the α data of the target end dot D0. Is compared with the value of the α data of the existing edge to obtain the larger value of α. In this case, in FIG. 11A, the other white portion in the frame is already painted with the upper end dot (α = 1), so there is no need to compare the value with the α data value of the target dot. .

FIG. 11B shows a case where it is determined by referring to the buffer BA that the left dot of the target end dot D0 draws an edge and the value of the α data is α = 1. It is. In this case, as shown in FIG. 11B, a portion of the right side of the frame WE is drawn and the value of the α data of the dot included in the frame WE is replaced with the α data of the target end dot D0. Value and α of existing edge
The value of the data is compared with the larger value of α. In this case, in FIG. 11B, other white portions in the frame are:
Since it is already painted with the left end dot (α = 1),
It is not necessary to compare with the value of the α data of the target dot.

FIG. 11C shows that the left and upper dots of the target edge dot D0 draw an edge, and that α
It is confirmed that the value of data is α = 1 in buffers BA and B.
B is determined with reference to FIG. In this case, FIG.
As shown by being filled with 1C, a portion of one dot at the lower right corner of the portion of the frame WE is drawn, and the value of the α data of the dot is set to the value of the α data of the target end dot D0.
In this case, the lower right corner portion is a portion that is not generated as an edge portion by the dot at the end along the scan up to that point. Therefore, since there is no existing edge, the α of the end dot D0 is compared without comparison. Value. In FIG. 11C, the other white portions in the frame have already been painted with left and upper end dots (α = 1).

FIG. 12 is a flowchart showing an example of a processing routine of the combined drawing data generation unit 10 in this case.

That is, first, in step 401, α data of the drawn image body is generated. Then, the process proceeds to step 402 to start scanning for edge generation. In this scan, as described above, the scan position is sequentially moved downward while scanning the drawn image body from the upper left to the right.

In the next step 403, it is determined whether or not the dot is an end dot as described above.
Judge using the data. If it is not a dot at the end, the process proceeds to step 404 to move to the next dot position,
Return to step 403. If it is determined in step 403 that the dot is an edge dot, the process proceeds to the case classification processing step 500 shown in FIG.

That is, as shown in FIG. 13, with reference to the buffers BA and BB described above, for the end dot detected in step 403, it is determined that neither the upper nor the left dot is an end dot. If it has been done (step 501), the process proceeds to step 511,
The processing shown in A is performed.

If it is determined that the dot above the end dot detected in step 403 is an end dot and α ≠ 1 (step 502), the process proceeds to step 5
Proceeding to 12, the processing shown in FIG. 10B is performed.

If the left dot of the edge dot detected in step 403 is an edge dot and it is determined that α ≠ 1 (step 503), the process proceeds to step 5
Proceeding to 13, the process shown in FIG. 10C is performed.

The upper and left dots of the end dot detected in step 403 are end dots, and α ド ッ ト
If it is determined to be 1 (step 504), the process proceeds to step 514 to perform the processing shown in FIG. 10D.

If it is determined that the dot above the edge dot detected in step 403 is an edge dot and α = 1 (step 505), the process proceeds to step 5
Proceeding to 15, the processing shown in FIG. 11A is performed.

If the left dot of the end dot detected in step 403 is an end dot and it is determined that α = 1 (step 506), the process proceeds to step 5
Proceeding to 16, the processing shown in FIG. 11B is performed.

When it is determined that the upper and left dots of the end dot detected in step 403 are end dots and α = 1 (step 507).
Then, the process proceeds to step 517 to perform the processing shown in FIG. 11C.

When the above-described case division processing is completed,
Proceeding to step 405, it is determined whether the target dot is the last dot of the drawn image body.
To repeat the above processing. If it is the last dot, the process proceeds to step 406, where the α plane of the drawn image body and the α plane of the edge are combined using CG anti-aliasing as described above, and the drawn image body and the edge are combined. Combine. Next, the process proceeds to step 407, where the synthesized image data with the edge and the α plane (the α plane of the edge) are transferred to the VRAMs 13, 14, and 15 via the graphic accelerator 12.

According to this example described above, the number of unnecessary memory accesses is reduced, and the edge and its α data can be generated at high speed. In the method of this example, the higher the quality of the drawn image body such as characters, the higher the quality of the edge can be obtained, and the processing time is the same regardless of the quality. Excellent in that there is.

Since high-speed processing is possible as described above, for example, character data can be superimposed on an image in real time. For example, in the case of a foreign language program, a music program, a flash report, etc. Can create subtitles.

In the above description, the case where the apparatus of the present invention is realized by a software algorithm has been described. However, as shown in FIGS. Since the α data generation processing is possible, it is of course possible to configure with hardware.

[0138]

As described above, according to the present invention, an edge is quickly added to a color drawing image such as a character or a figure to be displayed by being synthesized with a display image, and the outline data (α) is added. Data).

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining an embodiment of a composite drawing apparatus according to the present invention.

FIG. 2 is a block diagram illustrating another configuration of a device that combines a video signal and drawn image data.

FIG. 3 is a diagram used to explain a process for generating α data of a drawn image body.

FIG. 4 is a diagram used to explain a process for generating α data of a drawn image body.

FIG. 5 is a flowchart of an example of a processing routine for generating α data of a drawn image body.

FIG. 6 is a diagram used to describe an example of an edge generation and α data generation process according to the present invention;

FIG. 7 is a diagram used to describe an example of generation processing of an edge and α data thereof according to the present invention.

FIG. 8 is a flowchart of an example of an edge generation and α data generation processing routine according to the present invention;

FIG. 9 is a diagram for explaining a flag buffer used in another example of the edge generation and the α data generation process according to the present invention.

FIG. 10 is a diagram used for explaining another example of the generation processing of the edge and the generation processing of the α data according to the present invention.

FIG. 11 is a diagram used to explain another example of processing for generating an edge and generating α data according to the present invention.

FIG. 12 is a flowchart of another example of an edge generation and α data generation processing routine according to the present invention;

FIG. 13 is a diagram showing a part of the flowchart of FIG. 12;

FIG. 14 is a diagram for explaining composite drawing.

FIG. 15 is a diagram for explaining edges generated in a drawn image.

FIG. 16 is a diagram for explaining a conventional edge generation method and a method for generating α data thereof.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Synthetic drawing apparatus, 2 ... Display, 3 ... Keyboard, 4 ... Mouse, 11 ... Drawing data transfer buffer part, 1
2 ... Graphic accelerator, 13 ... VRAM, 14
... VRAM, 15 ... VRAM, 21 ... digital video mixer, 21a ... D / A conversion circuit, 22 ... key signal controller, 100 ... composite drawing data generator, 101 ... CP
U, 102 ROM, 103 RAM, 104 VRA
M, 105: display controller, 109: system bus, 111: I / O port, 31: input terminal, 3
2 ... A / D conversion circuit, 33 ... D / A conversion circuit, 34 ... D
/ A conversion circuit, 41, 42, 43: output terminal, LT: drawn image body, EG: edge portion

Claims (7)

[Claims] 1. A color drawing image data for combining a display image with a color drawing image such as a character or a figure, and contour data used for combining the color drawing image with the display image. A method of generating composite drawing data, comprising: detecting, from the outline data, an end of the color drawing image; and copying outline data of the drawing image data of the end around the periphery, thereby obtaining the color. A method for generating composite drawing data, comprising generating contour data for an edge having a predetermined width generated around a drawn image. 2. The drawing image data of another edge around the drawing image data of the edge is referred to, and the position of the drawing image data of the other edge around the drawing image data of the own edge is determined based on the position of the drawing image data of the own edge. 2. The method according to claim 1, wherein a peripheral position of copying the outline data of the drawn image data of the edge is changed. 3. A color drawing image data for combining a display image with a color drawing image such as a character or a graphic, and contour data used for combining the color drawing image with the display image. An edge detecting means for detecting an edge of the color depiction image from the edge data; and And an edge contour data generating means for generating contour data for an edge having a predetermined width generated around the color drawing image by copying the image data to the composite drawing data. 4. The edge contour data generating means refers to the drawn image data of another edge around the drawn image data of the edge, and draws its own edge of the drawn image data of another edge around the edge. 4. A peripheral position for copying the outline data of the drawn image data of the own edge according to the position with respect to the image data.
2. A device for generating combined drawing data according to claim 1. 5. A drawing input means for inputting drawing information of a drawing image such as a character or a figure, and drawing image data generating means for generating color drawing image data in accordance with information from the drawing input unit. A drawing image display unit that displays the color drawing image generated by the drawing image data generation unit on a display screen; a contour data calculation unit that obtains outline data for the color drawing image; From the contour data
Edge detection means for detecting the end of the color drawing image, and the contour data of the drawing image data of the end detected by the end detection means, by copying around the periphery, the color drawing image of the Edge contour data generating means for generating contour data for an edge having a predetermined width generated around the edge; and an edge-added drawing image for generating data of a color drawing image to which an edge is added based on the contour data for the edge. Generating means; an input terminal of a video signal of a display image for synthesizing the drawn image; and a video signal from the input terminal, the edged drawn image data, and the contour data calculated by the edge contour data calculating means. A combining drawing apparatus, comprising: combining means for combining using the output means; and an output terminal for outputting the image data combined by the combining means. 6. The edge contour data generating means refers to the drawn image data of another edge around the drawn image data of the edge, and draws its own edge in the drawn image data of the other edge around the edge. 6. A peripheral position for copying the outline data of the drawn image data of the own edge according to the position with respect to the image data.
3. The composite drawing apparatus according to 1. 7. A method for generating data of a color drawing image to be displayed by combining characters or a character with a display image, the method comprising detecting an end of the color drawing image, and centering the end on the end. A method of generating synthetic drawing data, characterized by adding an edge of the predetermined width to the color drawing image by filling an area of a predetermined width with information.