KR101106013B1 - edge list generation method in graphics accelerators and active edge list generation method - Google Patents

Abstract

The present invention relates to an edge list generation method of a graphic accelerator and an active edge list generation method using the same.
The edge list generation method and the active edge list generation method using the graphic accelerator of the present invention store the edge data for the edge list for each scan line sequentially in the edge list memory so that link information is not required, thereby reducing the memory usage. The next active edge list, which consists of active edge data that spans the next scan line for each scan line, is stored in the next active edge list memory separate from the memory where the edge list is stored, and then generated during the previous scan line processing. The active edge list is generated by reading the edge data stored in the active edge list memory and the edge data stored in the edge list memory for the current scan line processing, thereby reducing the number of memory accesses and reducing the power consumption of the graphics accelerator. Can and enhance the performance of the graphics accelerator Can hurt.

Description

Edge list generation method of graphics accelerator and active edge list generation method using the same {edge list generation method in graphics accelerators and active edge list generation method}

The present invention relates to an edge list generation method of a graphics accelerator and an active edge list generation method using the same. In particular, an edge list for outputting an image for each path data in a two-dimensional vector graphics accelerator And an edge list generation method of the graphics accelerator which can reduce the power consumption of the graphics accelerator and improve the performance of the graphics accelerator by reducing the number of memory accesses and the memory usage when generating the active edge list. It relates to an active edge list generation method using the same.

As the use of portable devices such as mobile phones, PDAs, and navigation devices increases, the development of user interfaces and hardware is being actively performed along with the development of contents for them.

In the case of these portable devices, processing operations such as rotation or enlargement / reduction of images are frequently performed to process image information, and a small amount of information is used to process such image information as compared to a bitmap method. Many vector graphics methods have been used, which have the advantage of reducing information loss and processing time.

The bitmap method stores the color values corresponding to each pixel in a certain format to represent an object. Therefore, when the object is enlarged or reduced, the color values for pixels that are not in the original image must be redefined by a predetermined interpolation method. As a result, image loss occurs.

On the other hand, in the case of the vector graphics method, a vertex, which is a basic unit, is used to represent a start point and an end point, and these vertices are gathered to generate an edge. In addition, since these edges gather to indicate the shape of the object, and after determining the shape, color is determined using separate color information, so when the object is enlarged or reduced, the object can be regenerated using the ratio of the enlargement or reduction. Therefore, the loss of the image can be prevented.

1 is a block diagram of a general two-dimensional vector graphics accelerator for outputting image data according to a vector graphics system.

As shown in FIG. 1, the two-dimensional vector graphics accelerator is composed of a tester 1, a rasterizer 3, an image generator 5, and a memory 7.

The tester 1 receives the vector data PD of the path data, and at each of the scanlines, the tester 1 receives a maximum value of the y-axis coordinates of the start point and the y-axis coordinates of the end point for each scanline. The edge data Ei located in the corresponding scan line to be stored is stored in the memory 7 to generate an edge list.

The rasterizer 3 sequentially reads each edge data Ei of the edge list stored in the memory 7, and consists of only active edge data that spans the corresponding scan line for each scan line. ) Is converted into a pixel pattern image PX corresponding to the vector graphics by the generated active edge list.

The image generator 5 receives the pixel pattern image PX and generates an image on the screen.

In general, in the case of the two-dimensional vector graphics accelerator, the edge list is large for processing the two-dimensional vector graphics, so the memory 7 composed of the edge list uses an external memory.

FIG. 2 is a diagram illustrating an image path for generating an image on a screen, FIG. 3 is a diagram showing a memory in which edge data for generating a conventional edge list for the image path of FIG. 2 is stored, and FIG. 3 is an edge list for FIG. 3, and FIGS. 5A to 5H are views illustrating a process for generating an active edge list using the edge list of FIG. 3, and FIG. 6 is an active edge list.

Each of the edge data Ei stored in the memory 7 to generate a conventional edge list and an active edge list is an address for referencing the next edge data for the edge list and the active edge list for each scan line. ) Has Link Information.

As shown in FIG. 2, when the scan line has six scan lines of SC1 to SC6 and the edge data has an image path having E1 to E12, a method of generating a conventional edge list is as follows.

As shown in FIG. 3, it can be seen that the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point of the first edge data E1 and the y-axis coordinate value of the end point is the end point, and the first edge data E1 is shown. Since the end point of the 1) is located in the first scan line SC1, the first edge data E1 belonging to the first scan line SC1 is stored in the M1 address of the memory. In the case of the second edge data E2, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the end point and belongs to the first scan line SC1, so the second edge data E2 is The link information of the first edge data E1 is set to L2. In the case of the third edge data E3, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the start point, and the start point of the third edge data E3 is the first scan line SC1. Since the third edge data E3 is stored in the address L3 of the memory, the link information of the second edge data E2 is set to L3, and the edge having the maximum value of the y-axis coordinate value belonging to the first scan line SC1. Since data does not exist, it is indicated by C to indicate that there is no link information related to the third edge data E3.

As such, it can be seen that the edge list for the first scan line SC1 is the first edge data E1, the second edge data E2, and the third edge data E3.

In the case of the fourth edge data E4, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the starting point, and the starting point of the fourth edge data E4 is the second scan line SC2. Since the fourth edge data E4 is stored at the M2 address of the memory, and the edge data having the maximum value of the y-axis coordinate value belonging to the second scan line SC2 does not exist, the link information related to the fourth edge data E4 is not included. Is denoted by C to indicate that it is not present.

In the case of the fifth edge data E5, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the start point, and the start point of the fifth edge data E5 is the fourth scan line SC4. ), The fifth edge data E5 is stored in the M4 address of the memory.

In case of the sixth edge data E6, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the starting point, and the starting point of the sixth edge data E6 is the sixth scan line ( SC6), the sixth edge data E6 is stored in the M6 address of the memory, and since the edge data having the maximum value of the y-axis coordinate value belonging to the sixth scan line SC6 does not exist, the sixth edge data ( C is indicated to indicate that there is no link information related to E6).

In the case of the seventh edge data E7, the y-axis coordinate value having the maximum value of the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the end point, and the end point of the seventh edge data E7 is the fifth scan line ( SC7), the seventh edge data E7 is stored in the M5 address of the memory, and since the edge data having the maximum value of the y-axis coordinate value belonging to the fifth scan line SC5 does not exist, the seventh edge data ( C is indicated to indicate that there is no link information related to E7).

In the case of the eighth edge data E8, the y-axis coordinate value having the maximum value of the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the end point of the eighth edge data E8, and this end point is the fourth scan line ( SC4), the fifth edge data E5 belongs to the fourth scan line SC4, and since the fifth edge data E5 is already stored at the M4 address of the memory, the eighth edge data E8 is stored in the memory. Store at the L8 address, and set the link information of the fifth edge data E5 to L8. In the case of the ninth edge data E9, the y-axis coordinate value having the maximum value is the end point of the ninth edge data E9, and since this end point belongs to the fourth scan line SC4, the ninth edge data E9 is stored in memory. At the L9 address, and set the link information of the eighth edge data E8 to L9. In the case of the tenth edge data E10, the y-axis coordinate value having the maximum value is the start point of the tenth edge data E10, and since this start point belongs to the fourth scan line SC4, the tenth edge data E10 is stored in memory. Is stored in the L10 address, and the link information of the ninth edge data E9 is set to L10. In the case of the eleventh edge data E11, the y-axis coordinate value having the maximum value is the end point of the eleventh edge data E11, and since this end point belongs to the fourth scan line SC4, the eleventh edge data E11 is the L11 address of the memory. And the link information of the tenth edge data E10 is set to L11, and since the edge data having the maximum value of the y-axis coordinate value belonging to the fourth scan line SC4 does not exist, the eleventh edge data E11 and Marked with C to indicate that there is no associated link information.

In the case of the twelfth edge data E12, the y-axis coordinate value having the maximum value among the y-axis coordinate value of the start point and the y-axis coordinate value of the end point is the end point, and the end point of the twelfth edge data E12 is the third scan line SC3. ), The twelfth edge data E12 is stored in the M3 address of the memory, and since the edge data having the maximum value of the y-axis coordinate value belonging to the third scan line SC3 does not exist, the twelfth edge data E12 Mark with C to indicate that there is no link information associated with.

As described above, the first edge data E1, E4, E12, E5, E7, and E6 belonging to the respective scan lines are sequentially provided to the memory specific address, that is, as shown in FIG. 3, M1, M2, M3, M4, M5, The data is stored at each M6 address, and the remaining edge data belonging to each scan line is stored at an arbitrary address corresponding to link information.

As shown in FIG. 4, the edge list corresponding to the first scan line SC1 is the first edge data E1, the second edge data E2, and the third edge data E3 by the above operation, and the second scan line. The edge list corresponding to (SC2) is the fourth edge data (E4), the edge list corresponding to the third scan line (SC3) is the twelfth edge data (E12), and the edge list corresponding to the fourth scan line (SC4) The fifth edge data E5, the eighth edge data E8, the ninth edge data E9, the tenth edge data E10, the eleventh edge data E11, and correspond to the fifth scan line SC5. It can be seen that the edge list is the seventh edge data E7 and the edge list corresponding to the sixth scan line SC6 is the sixth edge data E6.

Each edge of the edge list (Ei) of the edge list stored in the memory (7) for each scan line according to Figure 3 sequentially read active edge list consisting of only the edge data across the corresponding scan line for each scan line The process of generating is as follows.

As shown in FIG. 3, the first edge data E1 of the first scan line SC1 stored in the M1 address of the memory 7 is read and processed to generate the active edge list of the first scan line SC1, and the first edge is read. Since the data E1 has position coordinates for the start point and the end point, it is recognized that the data E1 is edge data belonging to the second scan line SC2. After processing the first edge data E1 by this operation, since the link information related to the first edge data E1 is L2, the second information stored in the memory 7 of the L2 address is accessed by accessing the L2 address of the memory 7. After the edge data E2 is read and processed, the third edge data E3 stored in the memory 7 of the L3 address is accessed by accessing the L3 address of the memory 7 by the link information L3 related to the second edge data E2. Since the link information related to the third edge data E3 is not present in C, it can be seen that the third edge data E3 is the last edge data belonging to the first scan line SC1. The process of generating an active edge list for SC1) ends.

Therefore, as shown in FIG. 6, the active edge data of the first scan line SC1 becomes E1, E2, and E3 sequentially.

The first edge data E1 and the third edge data E3 are edge data also belonging to the second scan line SC2, that is, active edge data of the second scan line SC2, and the second edge data E2 is the first scan line SC1. Since only the edge data belongs to the edge data, the link information associated with the first edge data E1 is updated from L2 to L3 for processing of the second scan line SC2 as shown in FIG. The link information is updated from L3 to C.

First edge data that is active edge data that spans the second scan line SC2 that is already recognized in the processing of the first scan line SC1, which is a previous scan line, to generate an active edge list for the second scan line SC2. It is necessary to read (E1) and the third edge data E3 and process the edge data that spans the second scan line SC2 which is the current scan line.

To this end, the M1 address of the memory 7 is first accessed to read and process the first edge data E1 stored in the M1 address, and the first edge data E1 is edge data belonging to the third scan line SC3, that is, the third scan line. It is recognized that it is the active edge data of (SC3). Since the link information related to the first edge data E1 is L3, the link information related to the first edge data E1 is approached to the L3 address of the memory 7 to read and process the third edge data E3 stored at the L3 address. Since the link information of the third edge data E3 is C, there is no address to link to, so the processing of the active edge data E1 and E3 of the second scan line SC2 recognized in the processing of the first scan line SC1 is finished. As shown, since the third edge data E3 is edge data belonging only to the second scan line SC2, the link information of the third edge data E3 is not updated.

For processing, the second scan line SC2, which is the current scan line, is accessed to the M2 address of the memory 7 to read and process the fourth edge data E4 stored at the M2 address. Since the link information for E4 is C, there is no more edge data for the second scan line SC2, so the process of generating the active edge list for the second scan line SC2 ends.

Since the first edge data E1 and the fourth edge data E4 are edge data that spans the third scan line SC3, that is, active edge data of the third scan line SC3, the first edge data E as shown in FIG. The link information of E1) is updated from L3 to M2.

Accordingly, as shown in FIG. 6, the active edge data of the second scan line SC2 are E1, E3, and E4 sequentially.

The process for generating an active edge list for the third scan line SC3 is as follows.

First, in order to process active edge data that spans the third scan line SC3, which is already recognized in the processing of the second scan line SC2, which is the previous scan line, the M1 address of the memory 7 is accessed to access the M1 address. It reads and processes the stored first edge data E1, and knows that the first edge data E1 does not span the fourth scan line SC4. After reading the first edge data E1, the link information related to the first edge data E1 is M2. Therefore, the link information associated with the first edge data E1 is M2, and the fourth edge data E4 stored at the M2 address is read and processed. Since the link information of the fourth edge data E4 is C, there is no address to link, so the processing of the active edge data E1 and E4 of the third scan line SC3 recognized in the process of the second scan line SC2 ends. Since the first edge data E1 is not edge data that does not span more scan lines, the link information of the first edge data E1 is updated from M2 to C as shown in FIG. 5C, and the fourth edge data ( Recognize that E4) is edge data that spans the fourth scan line SC4.

In order to process the third scan line SC3, which is the current scan line, the M3 address of the memory 7 is accessed to read and process the twelfth edge data E12 stored at the M3 address. In this case, the twelfth edge data E12 is read. Since the link information for C is no further edge data for the third scan line (SC3), the process of generating the active edge list for the third scan line (SC3) ends, and the fourth edge data (E4) and the twelfth edge data ( Since E12) is edge data that spans the fourth scan line SC4, which is the next scan line, that is, active edge data of the fourth scan line SC4, link information of the fourth edge data E4 is selected as C shown in FIG. 5D. Update to M3.

Therefore, as shown in FIG. 6, the active edge data of the third scan line SC3 are E1, E4, and E12 sequentially.

The process for generating an active edge list for the fourth scan line SC4 is as follows.

First, since the active edge data that spans the fourth scan line SC4 in the process of the third scan line SC3 which is the previous scan line is known as the fourth edge data E4 stored at the M2 address of the memory 7, The fourth edge data E4 is read and processed by accessing the M2 address of the memory 7, and it is recognized that the fourth edge data E4 does not span the fifth scan line SC5.

After reading the fourth edge data E4, the link information related to the fourth edge data E4 is M3. Therefore, the link information related to the fourth edge data E4 is M3, and the twelfth edge data E12 stored at the M3 address is read and processed. In this case, since the link information of the twelfth edge data E12 is C, there is no address to link, so the process of E4 and E12 which are active edge data of the third scan line SC3 recognized in the process of the third scan line SC3 is performed. When the fourth edge data E4 is not edge data that does not span any more scan lines, the link information of the fourth edge data E4 is updated from M3 to C as shown in FIG. 5E.

To process the fourth scan line SC4, which is the current scan line, the M4 address of the memory 7 is accessed to read and process the fifth edge data E5 stored at the M4 address. Since the related link information is L8, the 8th edge data (E8) is read and processed by accessing the L8 address of the memory, and the link information related to the 8th edge data (E8) is L9. The data E9 is read and processed, and the above process is repeated, and thus the link address associated with the eleventh edge data E11 is C, so that the tenth edge data E10 and the eleventh edge data E11 are sequentially read and processed. The active edge list generation process for the fourth scan line SC4 ends.

Since the ninth edge data E9 to eleventh edge data E11 are not all edge data that spans further scan lines, the eighth edge having link information for these edge data as shown in FIG. 5F. Update the link information associated with the data E8 from L9 to C, update the link information associated with the ninth edge data E9 from L10 to C, and update the link information associated with the tenth edge data E10 from L11 to C. Update to.

In addition, since the fifth edge data E5 and the eighth edge data E8 are the edge data that spans the fifth scan line SC5 which is the next scan line, that is, the active edge data of the fifth scan line SC5, The link information of the first edge data E5 is not updated.

Therefore, as shown in FIG. 6, the active edge data of the fourth scan line SC4 are sequentially E4, E12, E5, E8, E9, E10, and E11.

In order to generate the active edge list for the fifth scan line SC5, first, the active edge data that spans the fifth scan line SC5 in the processing of the fourth scan line SC4, which is the previous scan line, is stored in memory ( Since it is the fifth edge data (E5) stored at the M4 address of 7), it accesses the M4 address of the memory (7) to read and process the fifth edge data (E5), and the fifth edge data (E5) has six It is recognized that it is edge data that spans the first scan line SC6.

After reading the fifth edge data E5, the link information related to the fifth edge data E5 is L8. Therefore, the link information associated with the fifth edge data E5 is L8, and the eighth edge data E8 stored at the L8 address is read and processed. At this time, since the link information of the eighth edge data E8 is C, there is no address to link to, so the process of E5 and E8 which are active edge data of the fifth scan line SC5 recognized in the process of the fourth scan line SC4. To exit.

To process the fifth scan line (SC5), which is the current scan line, access the M5 address of the memory (7) to read and process the seventh edge data (E7) stored in the M5 address to the fifth scan line (SC5) Terminate the process of creating an active edge list.

Since the fifth edge data E5 and the seventh edge data E7 are edge data that spans the sixth scan line E6, which is the last scan line, link information of the fifth edge data E5 as shown in FIG. 5G. Is updated at L8 to the address M5 where the seventh edge data E7 is stored.

Accordingly, as shown in FIG. 6, the active edge data of the fifth scan line SC5 are E5, E8, and E7 sequentially.

In order to generate the active edge list for the last scan line, the sixth scan line SC6, first, the active spread over the sixth scan line SC6 in the processing of the previous scan line, the fifth scan line SC5, is performed. Since the edge data is known as the fifth edge data E5 stored at the M4 address of the memory 7, the fifth edge data E5 is read and processed by accessing the M4 address of the memory 7, and then the fifth edge. The link information M5 related to the data E5 is accessed to read and process the seventh edge data E7.

In this case, since the link information of the seventh edge data E7 is C, there is no address to link, so the processing of the active edge data E5 and E7 of the sixth scan line SC6 recognized in the process of the fifth scan line SC5 is performed. The process ends and the link information associated with the fifth edge data E5 is updated from M5 to C as shown in FIG. 5H.

To process the sixth scan line (SC6), which is the current scan line, access the M6 address of the memory (7) to read and process the sixth edge data (E6) stored at the M6 address to the sixth scan line (SC6). Terminate the process of creating an active edge list.

Accordingly, as shown in FIG. 6, the active edge data of the sixth scan line SC6 are sequentially E5, E7, and E6.

As described above, in order to generate an edge list and an active edge list, since all edge data are required link information for accessing the edge data, a memory having a large storage space for storing link information associated with each edge data is required. And the memory needs to be continuously accessed according to the link information, thereby increasing the number of memory accesses. Accordingly, the power consumption is large and the performance of the graphics device is degraded.

In addition, since the active edge data is processed for each scan line while updating the link information when the active edge list is generated by using the edge list stored in the memory, the process is complicated, which causes a problem of degrading the performance of the graphics device.

An object of the present invention is to store the edge data for the edge list for each scan line in the edge list memory sequentially so that link information is not required, thereby reducing the memory usage, and the current scan line currently being processed for each scan line. The next active edge list, which consists only of the active edge data that spans the next scan line of the next scan line, is stored in the next active edge list memory that is different from the edge list memory where the edge list is stored, The active edge list is generated by reading the edge data stored in the active edge list memory and the edge data stored in the edge list memory for the current scan line processing, thereby reducing the number of memory accesses and reducing the power consumption of the graphics accelerator. Can and improve the performance of the graphics accelerator Generating an edge list of the graphics accelerator way and to provide an active edge list generation method using the same.

In order to achieve the above object, the edge list generation method of the graphic accelerator of the present invention receives edge data, which is vector data having direction coordinates of the start point and the end point and generates the edge list for each scan line, to generate an image on the screen. An edge list generation method of a graphics accelerator for generating a data, comprising: an edge data receiving step of sequentially receiving edge data; Comparing the y-axis coordinate values of the start point and the end point of the edge data received in the edge data receiving step to detect a scan line belonging to the position of the point having a large value, and stores a plurality of edge data belonging to the corresponding scan line A scan line slot position selection step of selecting a position of a scan line slot having an edge data storage area and a link information storage area in which link information is stored; An edge data storage area determination step of determining whether there is an edge data storage area of an empty space for storing the received edge data in the scan line slot selected in the scan line slot position selection step; A link information updating step of updating link information of the link information storage area if the edge data storage area has no empty space for storing the received edge data in the edge data storage area determination step; A link slot storing step of storing the received edge data in a link slot storage area according to the link information updated in the link information updating step; In the edge data storage area determination step, if there is a storage area of an empty space for storing the received edge data, the edge data storage area is received in the edge data storage area of the scan line slot selected in the scan line slot position selection step. An edge data storage step of storing edge data; In the edge data storing step, if the edge data stored in the edge data storage area is the last edge data of the selected scan line, and the last edge data is detected, the link information storage area of the link information storage area is completed to complete generation of an edge list related to the corresponding scan line. A first scan line completion recording step of recording the scan line completion in the link information; And determining whether the currently received edge data is the last edge data for edge list generation. If the last edge data is the last edge data, the edge list generation is terminated. If not, the edge data receiving step sequentially receives the next edge data. And a final edge data determination step.

In order to achieve the above object, the method of generating an active edge list of the graphic accelerator according to the present invention sequentially reads edge data stored in an edge data storage area of a scan line slot corresponding to each scan line for each scan line and sequentially scans the corresponding edge data. A method for generating an active edge list of a graphic accelerator that generates an active edge list consisting of only edge data that spans a line, wherein each scan line includes only edge data that spans the next scan line, which is the next scan line of the current scan line currently being processed. A previous scanline edge data detection step of detecting a presence of edge data stored in the next active edge list memory during a previous scanline process by including a next active edge list memory in which a next active edge list is stored; If there is edge data stored in the next active edge list memory in the previous scan line edge data detection step, a first active edge list is generated by sequentially reading edge data stored in the next active edge list memory to generate a first active edge list. step; In the first active edge list generation step, first next scan line edge data detection for determining whether there is edge data that spans a next scan line among respective edge data stored in the next active edge list memory and sequentially read. step; A first next activity for storing edge data over a next scan line in the next active edge list memory if any of the edge data read in the first next scan line edge data detection step spans the next scan line An edge list storing step; Edge data stored in the next active edge list memory in the previous scan line edge data detection step, or each edge data stored in the next active edge list memory in the first next scan line edge data detection step and sequentially read. None of the edge data that spans the next scan line, or the edge data storage area of the scan line slot corresponding to the current scan line after storing the edge data in the next active edge list memory in the first next active edge list storage step A current scan line edge data reading step of sequentially reading edge data stored in the second data to generate a second active edge list; In the step of reading the current scan line edge data, it is determined whether there is edge data that spans the next scan line among the respective edge data stored in the edge data storage area of the scan line slot corresponding to the current scan line and sequentially read. A second next scan line edge data detection step; A second data for storing edge data over a next scan line in the next active edge list memory when there is edge data over a next scan line among edge data read in the second next scan line active edge data detection step; Storing the next active edge list; And determining whether the current scan line is the last scan line for generating the active edge list, and if the last scan line is terminated, ends the generation of the active edge list, and if not, the last scan line performs the previous scan line edge data detection step. Characterized in that the line determination step.

The edge list generation method and the active edge list generation method using the graphic accelerator of the present invention store the edge data for the edge list for each scan line sequentially in the edge list memory so that link information is not required, thereby reducing the memory usage. For each scan line, the next active edge list, which consists only of active edge data spanning the next scan line, the next scan line of the current scan line currently being processed, is the next active edge list separate from the memory where the edge list is stored. The number of memory accesses can be generated by reading the edge data stored in the next active edge list memory created by the previous scan line processing and the edge data stored in the edge list memory for the current scan line processing. Can reduce the overall speed of the graphics accelerator It is possible to reduce the consumption, it is possible to improve the performance of a graphics accelerator.

1 is a configuration diagram of a general two-dimensional vector graphics accelerator for outputting image data according to a vector graphics scheme;
2 is a view showing an image path for generating an image on a screen;
FIG. 3 is a diagram illustrating a memory in which edge data for generating a conventional edge list for the image path of FIG. 2 is stored;
4 illustrates a conventional edge list of FIG. 3;
5A to 5H illustrate a process for generating a conventional active edge list using the edge list of FIG. 3;
6 is a view showing a conventional active edge list,
7 is a flowchart of an edge list generation method of the present invention;
8 is a schematic structural diagram of an edge list memory storing an edge list according to the present invention;
9 is a flowchart of a method for generating an active edge list according to the present invention;
10A to 10G illustrate a process of storing edge data in a next active edge list memory of the present invention;
11A and 11B are diagrams for a tiger image and a subway image, respectively.

Hereinafter, an edge list generation method and an active edge list generation method using the graphic accelerator of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, FIG. 7 and FIG. 8, the edge list generation method of the graphic accelerator of the present invention includes an edge data receiving step S1 for receiving edge data sequentially and an edge data receiving step S1. Comparing the y-axis coordinate values of the start and end points of the edge data to detect the scan line belonging to the position of the point having a large value, and a plurality of edge data storage area (EM) for storing the edge data belonging to the corresponding scan line and Scan line slot position selection step S2 for selecting positions of scan line slots SS1 to SS6 having link information storage area LKM in which link information is stored, and scan selected in scan line slot position selection step S2. Edge data storage area determination step (S3) of judging whether there is an edge data storage area EM of empty space for storing the received edge data in the line slots SS1 to SS6, and edge data storage area determination. If there is no storage area of the empty space for storing the received edge data in the edge data storage area EM in the system S3, the link information updating step (S4) of updating the link information of the link information storage area LKM. And a link slot storage step S5 for storing the edge data received in the link slot storage area LSM according to the link information updated in the link information update step S4, and an edge data storage area determination step S3. If there is a storage area of the empty space for storing the received edge data in the edge data storage area EM, the edge data storage area of the scan line slots SS1 to SS6 selected in the scan line slot position selection step S2. Edge data storage step (S6) for storing the edge data received in (EM), and whether the edge data stored in the edge data storage area in the edge data storage step (S6) is the last edge data of the selected scan line detected First scan line completion recording step (S7) of recording the scan line completion (C) in the link information of the link information storage area (LKM) to complete the edge list generation associated with the corresponding scan line, if the last edge data; It is determined whether the currently received edge data is the last edge data E12 for edge list generation. If it is the last edge data E12, the edge list generation is terminated. If not, the edge data reception step S1 is performed. ) Consists of the last edge data determination step (S9) of sequentially receiving the next edge data.

In addition, the edge list generation method of the graphic accelerator detects whether the edge data stored in the link slot storage area LSM in the link slot storage step S5 is the last edge data E11 of the selected scan line. E11), a second scan line complete recording step S8 of recording the scan line completion C in the link slot storage area LS to complete generation of the edge list associated with the corresponding scan line may be further included.

As shown in FIGS. 9 to 10G, the method for generating an active edge list of the graphic accelerator stores a next active edge list including only edge data that spans the next scan line, which is the next scan line of the current scan line currently being processed. And a previous scan line edge data detection step (S10) for detecting whether there is edge data stored in the next active edge list memory (NAEL) during a previous scan line process by providing a next active edge list memory (NAEL). If there is edge data stored in the next active edge list memory NAEL in the line edge data detection step S10, edge data stored in the next active edge list memory NAEL is sequentially read to generate a first active edge list. First active edge list generation step (S20), and the first active edge list generation step (S20) the next active edge list A first next scan line edge data detection step S30 of determining whether there is edge data that spans a next scan line among respective edge data stored in the memory NAEL and sequentially read; and a first next scan line If there is edge data that spans the next scan line among the edge data read in the edge data detection step S30, the first next step of storing the edge data that spans the next scan line in the next active edge list memory NAEL. In the active edge list storage step S40 and the previous scan line edge data detection step S10, there is no edge data stored in the next active edge list memory NAEL or the first next scan line edge data detection step S30. In the next active edge list memory (NAEL), there is no edge data that spans the next scan line among the respective edge data sequentially read. B, the edge data storage area of the scan line slots SS1 to SS6 corresponding to the current scan line after storing the edge data in the next active edge list memory NAEL in the first next active edge list storing step S40; Current scan line edge data reading step (S50) of sequentially reading edge data stored in EM) to generate a second active edge list, and scanning corresponding to the current scan line in the current scan line edge data reading step (S50). Second next scan line edge data detection for determining whether there is edge data that spans the next scan line among the respective edge data stored in the edge data storage area EM of the line slots SS1 to SS6 and sequentially read out. If there is edge data that spans the next scan line among the edge data read in step S60 and the second next scan line active edge data detection step S60, the next scan line A second next active edge list storing step (S70) of storing the edge data spanning in the next active edge list memory (NAEL), and whether the current scan line is the last scan line (SC6) for generating the active edge list. If it is determined that the last scan line (SC6), the active edge list generation is terminated, and if not the last scan line (SC6) consists of the last scan line determination step (S80) for performing the previous scan line edge data detection step (S10). .

In addition, the next active edge list memory NAEL includes a read pointer rp and a recording pointer wp, which are stored at the position of the read pointer rp when reading edge data stored in the next active edge list memory NAEL. When the edge data is read out and the edge data is stored in the next active edge list memory NAEL, the edge data is stored in the position of the recording pointer wp.

Operation of the edge list generation method and the active edge list generation method using the graphic accelerator of the present invention according to the above configuration is as follows.

As shown in FIG. 2, an operation of an edge list generation method for an image path including six scan lines SC1 to SC6 and consisting of edge data of E1 to E12 is as follows.

As shown in FIG. 7, the edge data receiving step S1 sequentially receives edge data of E1 to E12.

Scan line slot position selection step (S2) detects the scan line belonging to the position of the point having a large value by comparing the y-axis coordinate values of the start and end points of the edge data received in the edge data receiving step (S1), and The positions of scan line slots SS1 to SS6 having a plurality of edge data storage areas EM for storing edge data belonging to the scan line and a link information storage area LKM for storing link information are selected. That is, as shown in FIG. 8, which is a schematic configuration diagram of the edge list memory 10 in which the edge list is stored, the edge list memory 10 corresponds to the six scan lines SC1 to SC6 of FIG. 2, respectively. Each of the scan line slots SS1 to SS6 includes a plurality of edge data storage areas EM for storing edge data and a link information storage area for storing link information. LKM). In addition, as shown in FIG. 8, when the storage space of the edge data storage area EM is insufficient in the fourth scan line slot SS4, the remaining edge data is stored in the link slot storage area LSM.

For example, assuming that the storage space of the edge data storage area EM for storing the edge data is four and the storage space of the link information storage area LKM is one, the first edge in the edge data receiving step S1. When the data E1 is received, as in the prior art, in the scan line slot position selection step S2, the first scan, which is the position of a point having a large value, is compared by comparing the y-axis coordinate values of the start point and the end point of the first edge data E1. The first scan line slot SS1 corresponding to the line SC1 is selected. In this manner, the corresponding scan line slot is selected for the last twelfth edge data E12 from the second edge data E2.

When the first edge data E1 is received in the edge data reception step S1, in the scan line slot position selection step S2, the first edge data E1 is transferred to the edge data storage area of the edge list memory 10 of FIG. Select the first scan line slot (SS1) to store in EM). In the edge data storage area determination step S3, the edge data storage area EM of the selected first scan line slot SS1 is completely empty. In the edge data storage step S6, the first edge data E1 is selected as the first scan line slot. The data is stored in the first storage area of the edge data storage area EM of (SS1).

By the same method as above, both the second edge data E2 and the third edge data E3 are edge data belonging to the first scan line slot SS1, and the edge data storage area EM of the first scan line slot SS1. Store sequentially in the second and third storage areas of. Since no further edge data need to be stored in the edge data storage area EM of the first scan line slot SS1, that is, the third edge data E3 is the last edge data related to the first scan line SC1, the first scan. In the line completion recording step S7, the scan line completion C is stored in the link information of the link information storage area LKM to indicate the completion of the edge list generation associated with the first scan line.

As described above, when the fourth edge data E4 is received in the edge data receiving step S1, in the scan line slot position selection step S2, the fourth edge data E4 is scanned in the second scan line S2. Since the edge data storage area EM of the second scan line slot SS2 is completely empty in the edge data storage area determination step S3, the line slot SS2 is selected, and thus the fourth edge data in the edge data storage step S6. The first scan line E4 is stored in the first storage area of the edge data storage area EM of the second scan line slot SS2, and the fourth edge data E4 is the last edge data related to the second scan line SC1. In the completion recording step S7, the scan line completion C is stored in the link information of the link information storage area LKM to indicate the completion of the edge list generation associated with the second scan line SC1.

When the fifth edge data E5 is received in the edge data receiving step S1, in the scan line slot position selecting step S2, the fourth scan line slot corresponding to the fifth edge data E5 in the fourth scan line S4 is received. (SS4) is selected, and in the edge data storage area determination step S3, the edge data storage area EM of the fourth scan line slot SS4 is completely empty, so the fifth edge data (S6) is selected in the edge data storage step S6. E5) is stored in the first storage area of the edge data storage area EM of the fourth scan line slot SS4.

When the sixth edge data E6 and the seventh edge data E7 are received in the edge data receiving step S1, the sixth edge data E6 is divided into the sixth scan line slot SS6 by the same method as described above. The seventh edge data E7 is stored in the first storage area of the edge data storage area EM of the fifth scan line slot SS5.

In the first scan line complete recording step S7 since the last edge data of the sixth edge data E6 and the seventh edge data E7 is the last edge data associated with the sixth scan line SC6 and the fifth scan line SC5, respectively. The scan line completion C is stored in the link information of the link information storage area LKM to indicate the completion of the list generation.

When the eighth edge data E8, the ninth edge data E9, and the tenth edge data E10 are received in the edge data receiving step S1, all of these edge data are stored in the fourth scan line slot SS4. As belonging edge data, the edge data is sequentially stored in the second, third, and fourth storage areas of the edge data storage area EM of the fourth scan line slot SS4.

When the eleventh edge data E11 is received in the edge data receiving step S1, the eleventh edge data E11 is edge data belonging to the fourth scan line slot SS4 or the fourth scan in the edge data storage area determination step S3. Since the edge data storage area EM of the line slot SS4 is completely filled and the eleventh edge data E11 cannot be stored in the edge data storage area EM, the fourth scan line slot SS4 in the link information update step S4. Update the link information of the link information storage area LKM to LK, and store the eleventh edge data E11 in the link slot storage area LSM in the link slot storage step S5. .

Since the eleventh edge data E11 stored in the link slot storage area LSM is the last edge data of the fourth scan line SC4, in the second scan line complete recording step S8, the edge list generation associated with the fourth scan line SC4 is generated. Scan line completion C is recorded in the link slot storage area LS for completion.

When the twelfth edge data E12 is received in the edge data receiving step S1, the twelfth edge data E12 is the first of the edge data storage area EM of the second scan line slot SS2 by the same method as described above. Since the twelfth edge data E12 is the last edge data associated with the second scan line SC2, in the first scan line completion recording step S7, the link information storage area is displayed to indicate the completion of the edge list generation. The scan line completion C is stored in the link information of the LKM.

In the last edge data determination step S9, since the twelfth edge data E12 is the last edge data for edge list generation, the edge list generation is completed.

As described above, the edge list generation method of the present invention does not have link information for referring to the next edge data for edge list generation in each of the edge data, and corresponds to each of the scan lines SC1 to SC6. Edge data is sequentially stored in the edge data storage area EM for each scan line slot SS1 through SS6, and link information is stored in one link information storage area LKM for each scan line slot SS1 through SS6. Since it is stored, it is possible to reduce the amount of memory used compared to the conventional.

The operation of the method of generating an active edge list of the graphic accelerator of the present invention using the edge list stored in the edge list memory 10 shown in FIG. 8 is as follows.

As shown in FIGS. 10A to 10G, the next active edge list memory (NAEL) is another memory separate from the edge list memory 10, and is the next one after the current scan line currently being processed for each scan line SC1 to SC6. The next active edge list, which consists only of the edge data spanning the next scan line, which is the scan line, is stored. The next active edge list memory NAEL includes a read pointer rp and a recording pointer wp so that the edge stored at the position of the read pointer rp when reading the edge data stored in the next active edge list memory NAEL. When reading data and storing edge data in the next active edge list memory NAEL, it is assumed that a circular queue memory that stores edge data at the position of the recording pointer wp is used.

As shown in FIG. 9, since the first scan line SC1 is the first scan line for generating an active edge list, the next active edge list memory NAEL is completely empty as shown in FIG. 10A, and thus the previous scan line edge data detection step is performed. In S10, since there is no edge data stored in the next active edge list memory NAEL, the current scan line edge data reading step S50 is performed.

In the current scan line edge data reading step S50, first edge data E1 and second stored in the edge data storage area EM of the first scan line slot SS1 corresponding to the first scan line SC1 which is the current scan line. The edge data E2 and the third edge data E3 are sequentially read. At this time, the second active edge list which is the active edge list of the first scan line SC1 is E1, E2, and E3.

The second next scan line active edge data detection step S60 is performed in the edge data storage area EM of the first scan line slot SS1 corresponding to the first scan line SC1 in the current scan line edge data reading step S50. An edge that spans the next scan line, that is, the second scan line SC2, for the first edge data E1, the second edge data E2, and the third edge data E3 which are stored and sequentially read respective edge data. It is determined whether there are active edge data that are data. Accordingly, it can be seen that the first edge data E1 and the third edge data E3 are active edge data which are edge data that spans the second scan line SC2.

In the second next active edge list storing step S70, the first edge data E1 and the third edge data E3, which are edge data that spans the second scan line SC2, are stored in the next active edge list memory NAEL. At this time, since the read pointer rp and the write pointer wp are initially located in the first storage area of the next active edge list memory NAEL as shown in FIG. 10A, the next active edge list memory ( The first edge data E1 in the NAEL is stored (written) in the first storage area of the next active edge list memory NAEL, and the recording pointer wp is located in the second storage area of the next active edge list memory NAEL. The third edge data E3 is stored in the second storage area of the next active edge list memory NAEL, and the recording pointer wp is located in the second storage area of the next active edge list memory NAEL. In this manner, each time the edge data is stored in the next active edge list memory NAEL, the recording pointer wp is increased by one, and the circular queue memory is circulated to the first position as shown in FIG. 10D. Similarly, when reading edge data stored in the next active edge list memory NAEL, the read pointers rp are incremented by one and then circulated to the first position.

The annular queue memory circulated using the read pointer rp and the write pointer wp is a general operation, and an operation thereof will be omitted.

When the processing for the first scan line SC1 is completed, the processing of the second scan line SC2 which is the next scan line is started because it is not the last scan line SC6.

Since the first edge data E1 and the third edge data E3 are stored in the next active edge list memory NAEL in the first scan line SC1 which is the previous scan line in the previous scan line edge data detection step S10, In the first active edge list generation step S20, the first edge data E1 and the third edge data E3 are generated as the active edge lists of the second scan line, and the first active edge lists E1 and E3 are generated.

In the first next scan line edge data detection step S30, the next scan line is stored for each of the first edge data E1 and the third edge data E3 stored in the next active edge list memory NAEL and sequentially read. In this case, it is determined whether there is edge data that spans the third scan line SC3. In this case, since the first edge data E1 is edge data that spans the third scan line SC2, the first next active edge is shown in FIG. 10C. In the list storage step S40, the first edge data E1 is stored in the third storage area of the next active edge list memory NAEL.

After storing the first edge data E1 spanning the third scan line SC3 in the next active edge list memory NAEL in the first next active edge list storage step S40, the current scan line edge is stored in the same manner as described above. The data reading step S50, the second next scan line active edge data detection step S60, and the second next active edge list storing step S70 are performed.

That is, in the current scan line edge data reading step S50, the fourth edge data E4 stored in the edge data storage area EM of the second scan line slot SS2 corresponding to the second scan line SC2 is read. At this time, the second active edge list of the second scan line SC2 is E4.

Accordingly, in the active edge list of the second scan line SC2, the first active edge list E1 and E3 and the second active edge list E4 generated in the first active edge list generation step S20 are generated.

In the second next scan line active edge data detection step S60, the fourth edge data E4 stored in the edge data storage area EM of the second scan line slot SS2 for processing the second scan line SC2 which is the current scan line. ) Is determined as the active edge data that is the next scan line, that is, the edge data that spans the third scan line SC3, and the fourth edge data E4 is the active edge that is the edge data that spans the third scan line SC3. In the second next active edge list storing step (S70), as shown in FIG. 10C, the fourth edge data E4 is used as edge data that spans the third scan line SC3, and the fourth active edge list memory NAEL is the second data. Save to storage area.

The third scan line SC3, the fourth scan line SC4 and the fifth scan line SC5 are processed in the same manner as the processing of the second scan line SC2, and the first active process is performed when the third scan line SC3 is processed. The edge list is E1 and E4 stored in the next active edge list memory NAEL during the processing of the second scan line SC2, and the second active edge list is a column stored in the edge data storage area EM of the third scan line slot SS3. Since the second edge data E12 is E12, the active edge list for the third scan line SC3 is generated by E1, E4, and E12, and is processed in the next active edge list memory NAEL by the processing of the third scan line SC3. As shown in FIG. 10D, the fourth edge data E4 and the twelfth edge data E12 that are connected to the fourth scan line SC4 are stored.

When processing the fourth scan line (SC4), the first active edge list is E4, E12 stored in the next active edge list memory (NAEL) when processing the third scan line (SC3), and the second active edge list is the fourth scan line slot (SS4). 5th edge data (E5), 8th edge data (E8), 9th edge data (E9), 10th edge data (E10), and 4th scan line slot (SS4) stored in the edge data storage area EM of The eleventh edge data (E11) stored in the link slot storage area (LSM) according to the link information LK address of E5, E8, E9, E10, E11. Therefore, the active edge list for the fourth scan line (SC4) is E4, E12, E5, E8, E9, E10, and E11 are generated, and by processing of the fourth scan line SC4, the next active edge list memory NAEL is connected to the fifth scan line SC5 as shown in FIG. 10E. The first edge data E5 and the eighth edge data E8 are stored.

When processing the fifth scan line (SC5), the first active edge list is E5, E8 stored in the next active edge list memory (NAEL) when processing the fourth scan line (SC4), and the second active edge list is the fifth scan line slot. Since the seventh edge data E7 stored in the edge data storage area EM of SS5, the active edge list for the fifth scan line SC5 is generated by E5, E8, E7, and the fifth scan line SC5. In the next active edge list memory NAEL, the fifth edge data E5 and the seventh edge data E7, which are bound to the sixth scan line SC6, are stored in the next active edge list memory NAEL.

When processing the last scan line, the sixth scan line (SC6), the first active edge list is E5, E7 stored in the next active edge list memory (NAEL) when the fifth scan line (SC5) is processed, and the second active edge list is Since the sixth edge data E6 stored in the edge data storage area EM of the sixth scan line slot SS6, the active edge list for the sixth scan line SC6 is generated by E5, E7, and E6. By the processing of the first scan line SC5, no edge data is stored in the next active edge list memory NAEL as shown in Fig. 10G.

As described above, the method for generating an active edge list of the graphic accelerator according to the present invention includes an edge list including a next active edge list including only active edge data that spans the next scan line that is the next scan line of the current scan line currently being processed. It saves in the next active edge list memory that is different from the stored memory and reads the edge data stored in the next active edge list memory and the edge data stored in the edge list memory for the current scan line processing. By generating the edge list, the number of memory accesses can be reduced, thereby reducing the power consumption of the graphics accelerator and improving the performance of the graphics accelerator.

Table 1 below shows experimental results of applying a graphic accelerator using the prior art and the present invention to the tiger image of FIG. 11A and the subway images of FIG. 11B. Each edge data is 64 bits, and the edge list memory is an external memory. Next, the next active edge list memory uses the internal memory in the central processing unit consisting of the annular queue.

As shown in Table 1, when the edge list generation method of the graphic accelerator of the present invention and the active edge list generation method of the present invention using the edge list according to the present invention are applied, the memory usage space is reduced in comparison with the prior art, and It can be seen that the number of memory accesses can be significantly reduced.

Prior art Invention
XGA

External memory space
Tiger footage 3,276,228 2,827,044 Subway footage 2,224,200 1,862,136 External memory access count
Tiger footage 7,542,276 4,682,420 Subway footage 5,121,516 3,172,505
VGA

External memory space Tiger footage 3,276,132 2,703,780 Subway footage 2,271,072 1,837,044 External memory access count Tiger footage 7,187,892 4,668,596 Subway footage 4,809,468 3,232,212

Claims (5)

In the method of generating an edge list of a graphics accelerator for generating an edge list for each scan line (SC1 to SC6) by receiving edge data, which are directional vector data having position coordinates of a start point and an end point, to generate an image on a screen. ,
An edge data receiving step S1 for sequentially receiving edge data;
Comparing the y-axis coordinate values of the start point and the end point of the edge data received in the edge data receiving step (S1) to detect the scan line belonging to the position of the point having a large value, and to store the edge data belonging to the corresponding scan line A scan line slot position selection step (S2) of selecting positions of scan line slots SS1 to SS6 having a plurality of edge data storage regions EM and a link information storage region LKM for storing link information;
Edge data storage area determination step of determining whether there is an edge data storage area (EM) in the empty space for storing the edge data received in the scan line slots (SS1 to SS6) selected in the scan line slot position selection step (S2) (S3);
In the edge data storage area determination step (S3), if there is no storage area in the edge data storage area EM for storing the received edge data, the link information of the link information storage area LKM is updated. Link information updating step (S4);
A link slot storage step (S5) of storing the edge data received in the link slot storage area LS according to the link information updated in the link information updating step (S4);
In the edge data storage area determination step (S3), if there is a storage area of an empty space for storing the received edge data in the edge data storage area (EM), the scan line selected in the scan line slot position selection step (S2) An edge data storage step S6 for storing the received edge data in the edge data storage area EM in the slots SS1 to SS6;
In the edge data storage step S6, it is detected whether the edge data stored in the edge data storage area EM is the last edge data of the selected scan line. If the edge data is the last edge data, the edge list related to the corresponding scan line is completed. A first scan line completion recording step (S7) of recording the scan line completion C in the link information of the link information storage area LKM;
It is determined whether the currently received edge data is the last edge data E12 for edge list generation. If it is the last edge data E12, the edge list generation is terminated. If not, the edge data reception step S1 is performed. ) Is a final edge data determination step (S9) of sequentially receiving the next edge data.
The method of claim 1, wherein the edge list generation method of the graphic accelerator detects whether edge data stored in the link slot storage area LSM is the last edge data E11 of the selected scan line in the link slot storage step S5. In the case of the last edge data E11, a second scan line completion recording step S8 is further provided to record the scan line completion C in the link slot storage area LS to complete generation of the edge list associated with the corresponding scan line. Edge list generation method of the graphics accelerator, characterized in that.
Active edge list consisting of only the edge data that spans the corresponding scan line by sequentially reading the edge data stored in the edge data storage area EM of the scan line slots SS1 to SS6 corresponding to each scan line sequentially. In the method of generating an active edge list of the graphics accelerator for generating a,
For each scan line, the next active edge list memory (NAEL), which stores only the next active edge list consisting of edge data that spans the next scan line, which is the next scan line of the current scan line, is processed. A previous scan line edge data detection step (S10) of detecting whether there is edge data stored in the next active edge list memory (NAEL);
If there is edge data stored in the next active edge list memory NAEL in the previous scan line edge data detection step S10, the edge data stored in the next active edge list memory NAEL is sequentially read and the first active edge list is read. Generating a first active edge list (S20);
A first active edge list generation step (S20) in the next active edge list memory (NAEL) stored in the next sequentially read each edge data of the edge data that spans the next scan line to determine whether there is A next scan line edge data detection step (S30);
If there is edge data that spans the next scan line among the edge data read out in the first next scan line edge data detection step S30, the edge data that spans the next scan line is stored in the next active edge list memory NAEL. Storing the first next active edge list (S40);
There is no edge data stored in the next active edge list memory NAEL in the previous scan line edge data detection step S10, or the next active edge list memory NAEL in the first next scan line edge data detection step S30. None of the edge data that is stored in the sequential edge data and is sequentially read from the next scan line, or the edge data is stored in the next active edge list memory NAEL in the first next active edge list storage step S40. After scanning the current scan line edge data step of sequentially reading the edge data stored in the edge data storage area EM of the scan line slots SS1 to SS6 corresponding to the current scan line to generate a second active edge list. (S50);
The next scan of each edge data stored in the edge data storage area EM of the scan line slots SS1 to SS6 corresponding to the current scan line and sequentially read in the current scan line edge data reading step S50. A second next scan line edge data detection step S60 of determining whether there is edge data that spans the line;
If there is edge data that spans the next scan line among the edge data read in the second next scanline active edge data detection step (S60), the edge data that spans the next scan line is stored in the next active edge list memory (NAEL). Storing the second next active edge list (S70); And
It is determined whether the current scan line is the last scan line (SC6) for generating the active edge list. If the last scan line (SC6) is terminated, the generation of the active edge list is terminated. If not, the previous scan line edge is detected. And a final scan line determination step (S80) of performing a data detection step (S10).
4. The read next pointer according to claim 3, wherein the next active edge list memory (NAEL) includes a read pointer (rp) and a write pointer (wp) so as to read edge data stored in the next active edge list memory (NAEL). The edge data stored at the position of rp is read, and the edge data is stored at the position of the recording pointer wp when the edge data is stored in the next active edge list memory NAEL. How to create.
The method according to claim 4, wherein the next active edge list memory (NAEL) is an annular queue memory.

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