JP4307763B2 - Image processing system and car navigation system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to image processing for displaying character information or the like using a bitmap font or dot matrix font on a background screen, and relates to a technique effective when applied to, for example, a car navigation system.
[0002]
[Prior art]
In a display using a bitmap font or dot matrix font on a low-resolution display, jaggedness (alias) may occur at the boundary between the background and the character depending on the size of the display pixel, and the character may be difficult to see. As a technique for solving this problem, Japanese Patent Application Laid-Open No. 5-40463 automatically multi-tones the boundary portion between the background color and the character color for each dot with respect to the character shape data corresponding to the character code. A technique has been proposed in which multi-gradation characters are generated at high speed by performing blend processing.
[0003]
[Problems to be solved by the invention]
However, in the above prior art, in order to obtain multi-gradation character information, it is necessary to read font data and perform an operation for multi-gradation of the boundary portion between the background color and the character color for each dot. The burden is heavy. Before the CPU issues a drawing command by the graphic processor, it is necessary to perform blend processing for such multi-gradation. In short, the CPU reads the font shape data from the memory, performs a multi-gradation operation on the data, and stores the operation result in the work area of the memory. Thereafter, the CPU issues a drawing command using the multi-gradation data to the graphic processor, and the graphic processor that responds to this reads the multi-gradation-processed font data from the work area and follows the instruction of the command to the frame buffer. To draw. In this way, it has been clarified that memory access must be performed many times to display characters on the background.
[0004]
An object of the present invention is to provide an image processing system capable of easily drawing a pattern on a background screen with little burden on a CPU.
[0005]
Another object of the present invention is to provide a car navigation system that can relatively easily reduce the jagged boundary between characters and the like displayed on the screen even when the background screen changes from moment to moment. It is to provide.
[0006]
The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.
[0007]
[Means for Solving the Problems]
[1] The outline of representative ones of the inventions disclosed in the present application will be briefly described as follows.
[0008]
That is, the CPU issues a specific drawing command (anti-alias font command) that uses the blend ratio between the background and the pattern of characters as data, and blends the colors of the background and the pattern of characters. A drawing control unit such as a drawing processor responds to this. When the anti-alias font command is activated, the drawing control unit reads the data (ratio data) of the mixing ratio information (a_value) indicating the degree of mixing (mixing ratio) from the specified location, In addition, the drawing data (background data) is read from the specified drawing data storage location, and the color of the specified pattern, for example, the character color and the drawing data that has been read are mixed using the mixing ratio information corresponding to each pixel. Then, the mixed data is written back to a drawing data storage location such as a frame buffer. The processing for the drawing data (background data) performed by the drawing processor is a read-modify-write process.
[0009]
The specific drawing command issued by the CPU includes, for example, a character size (for example, the height and width of a character pattern, or two or four vertices of a pattern rectangle), a drawing data storage location (start point, two vertices, Or the storage location of the ratio data (indicated by a memory address, coordinates, etc.), the character color, and a specific command code. When the CPU issues this specific drawing command (anti-alias font command), the drawing control unit can draw a pattern such as a smooth character in a designated drawing data storage location.
[0010]
[2] The present invention will be described in more detail. The image processing system includes a CPU (1), a drawing control unit (8), and a frame buffer (FBM). The drawing control unit generates a plurality of patterns in response to a specific drawing command issued from the CPU. Based on ratio data (10) that defines pixel units in gradation, first data (11) that defines the background of the pattern, and second data (12) that defines the unit color or unit pattern of the pattern The ratio data can be drawn in the frame buffer by mixing the second data with the first data at a gradation defined in pixel units. The ratio data is, for example, data that defines the edge and center of the pattern in units of pixels with a plurality of gradations.
[0011]
According to the above, the state of the boundary portion between the pattern and the background is determined according to the ratio data. By blending the unit color of the pattern and the background color in the boundary portion, the jaggedness in the boundary portion becomes inconspicuous, in other words, the boundary line becomes smooth and the pattern of characters and the like becomes easy to see. In order to realize such a blending process, the CPU does not have to burden the blending operation using the background data and the pattern data until the drawing processor can draw as it is. On the other hand, the drawing unit may not be able to bear all the calculations, and in the read / modify / write operation of the background data, the second data is mixed with the first data (background data) using the ratio data. The data obtained by mixing may be written back to the frame buffer.
[0012]
As a desirable mode, the ratio data may be data for a plurality of pixels corresponding to a font pattern corresponding one-to-one with a font code. The CPU does not need to generate ratio data at all, and the processing load on the CPU is drastically reduced.
[0013]
The specific drawing command includes, for example, a specific command code, a storage address of the ratio data, an area size of a pattern defined by the ratio data, a first address of the first data, and the second data. The CPU can instruct the drawing unit to perform a necessary drawing operation only by storing such a specific drawing command as a command list in the command buffer or command FIFO in the order of processing.
[0014]
For example, the first address of the first data is a memory address on the frame buffer. The storage address of the ratio data is a memory address on the work area (TXM). At this time, the frame buffer and work area are allocated to a memory (4) connected to the drawing control unit via a local bus (6) different from a common bus (5) shared by the CPU and the drawing control unit. May be. The frequency at which the memory access by the drawing control unit and the memory access by the CPU compete with each other can be reduced, which contributes to speeding up of data processing. The frame buffer and work area may be allocated to a memory (2) connected to a common bus shared by the CPU and the drawing control unit. In this case, it is necessary to employ a common bus having a large number of parallel bits so that the loss due to the contention can be substantially ignored. If this condition can be satisfied, the CPU can read the ratio data from, for example, a CD-ROM drive into the work memory of the CPU, and transfer the ratio data from the memory to the local memory. Further, a frame buffer may be allocated to the memory (4) connected to the local bus, and a work area may be allocated to the memory (2) connected to the common bus.
[0015]
The data processing system may include a display control unit (42) configured to control the drawing control unit to display data stored in the frame buffer on a display. Further, the data processing system may include a recording information reproducing unit (25) that reads and reproduces the ratio data from a recording medium such as a CD-ROM. At this time, the drawing control unit can use the ratio data reproduced by the recorded information reproducing unit. The CPU may perform a pattern modification process such as a proportional process for a European character font on the ratio data reproduced by the recorded information reproducing unit. The drawing control unit may receive the ratio data subjected to the pattern modification process from the CPU and process it.
[0016]
[3] As a data processing system, attention is focused on a car navigation system using a display with a relatively low resolution. The car navigation system includes a position detection unit (26) and a control unit capable of displaying map information corresponding to the position detected by the position detection unit on the display unit and displaying character information superimposed on the displayed map information. And having. The control unit includes a CPU (1), a drawing control unit (8), and a memory (2, 4). The drawing control unit responds to a specific drawing command issued from the CPU, ratio data defining a pattern in units of pixels with a plurality of gradations, first data defining a background of the pattern, and the pattern The second data is mixed with the first data at a gradation that the ratio data defines in units of pixels based on the second data that defines the unit color or unit pattern of the pattern data, and pattern data obtained by mixing the second data is obtained. Drawing is possible in the memory. The ratio data may be data that defines an edge portion and a center portion of a pattern in a plurality of gradations in units of pixels. The ratio data may be data for a plurality of pixels corresponding to a font pattern corresponding one-to-one with a font code. Even if a relatively low-resolution display such as a car navigation system is adopted, street names and addresses can be easily displayed on a map.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a first example of an image processing system according to the present invention centering on a drawing processing system. Although not particularly limited, the image processing system includes a CPU (central processing unit) 1, a main memory 2, a graphic processor 3, and a local memory 4 as representatively shown data processing units. The CPU 1, main memory 2 and graphic processor 3 share a system bus 5, and the local memory 4 is connected to the graphic processor 3 via a local bus 6. The CPU 1 has an instruction control unit that fetches and decodes an instruction to be executed, and an arithmetic unit that performs a data operation and an address operation in accordance with an instruction decoding result. The main memory 2 is composed of, for example, an SRAM (Static Random Access Memory), and serves as a data temporary storage area of the CPU 1 and a storage area for application programs. The OS (operating system) of the CPU 1 is held in a read only memory (ROM) (not shown). The application program is downloaded to the main memory 2 from a disk drive device (not shown) or the like.
[0018]
The local memory 4 is composed of, for example, SDRAM (synchronous dynamic RAM), a frame buffer area FBM, a texture area TXM in which basic data of image processing such as ratio data described later is stored, and a display list in which a command string is stored. Such as a command list area CDM. The texture area TXM and the command list area CDM are examples of work areas.
[0019]
The graphic processor 3 has a drawing control unit 8. Although not particularly limited, the drawing control unit 8 sequentially executes commands written in the command list area CDM to draw image data in the frame buffer area FBM. The command list is written in the command list area CDM by the CPU 1 in advance.
[0020]
The drawing control unit 8 has a pixel color mixture (blend) calculation function. This function is realized by the drawing control unit 8 executing a specific drawing command, for example, an anti-alias font command.
[0021]
FIG. 2 illustrates the contents of pixel color mixture calculation processing. Schematically, ratio data 10 that defines a character pattern (here, alphabet A) in a plurality of gradations in pixel units, background data (first data) 11 that defines the background of the pattern, and unit colors of the pattern Based on the color data (second data) 12 that defines the pixel data, a pixel color mixture calculation is performed to form the data by mixing the color data 12 with the background data 11 at a gradation that the ratio data 10 defines in pixel units. . The image information 13 obtained by the pixel color mixture calculation is written back and drawn in the area where the background data 11 is read from the frame buffer area FBM.
[0022]
The ratio data 10 is, for example, data that defines the edge and center of a character pattern in units of pixels with a plurality of gradations. This can be grasped as data used in place of the font pattern for each character code. For example, the ratio data 10 corresponding to the font A may be defined as data corresponding to the character code of the alphabet A. In the example of FIG. 2, the ratio data is 4-bit / pixel data (value 0 to value 15). In hexadecimal notation, H′0 is background data 100%, H′F is color data 100%, and H′8. Means a mixture of 50% background data and 50% color data. The CPU does not need to perform calculation each time based on binary font data for each font to obtain ratio data. Instead of character font data, the ratio data may be provided on a removable disk or ROM and downloaded to the basic data area TXM of the local memory 4 in advance. The CPU 1 does not need to generate any ratio data, and the processing load on the CPU 1 is reduced.
[0023]
The background data 11 and the color data (character color) 12 are 16-bit / pixel true data relating to the three primary colors of red, green, and blue. The number of data bits may be 24 bits / pixel. Similarly, the number of bits of the ratio data 10 may be increased as appropriate, or a floating point number may be used.
[0024]
The background data 11 is, for example, background data of an area where characters on the frame buffer area FBM are to be displayed. Data in a required area may be read from the frame buffer area FBM of the local memory 4 and used.
[0025]
A specific example of the color mixture calculation method will be described. If the ratio data 10 for each font is an integer value (a_value) of 4 bits / pixel, the color data value of 16 bits / pixel is TCOLOR, and the pixel data of the background data is the drawing destination data Ds, the corresponding pixels of the background data The pixel data Dd to be redrawn with respect to the red, green, and blue components is, for example, the following approximate expression:
Dd (red) ≒ (TCOLOR (red) * a_value) / 15 + Ds (red) * (15-a_value)) / 15
Dd (green) ≈ (TCOLOR (green) * a_value) / 15 + Ds (green) * (15−a_value)) / 15
Dd (blue) ≒ (TCOLOR (blue) * a_value) / 15 + Ds (blue) * (15-a_value)) / 15
As good as The symbol * means multiplication.
[0026]
In the pixel calculation, division must be performed by 15. To divide this by 16, that is, a 4-bit shift operation,
(1) When a_value = 15
Dd (red) = TCOLOR (red), Dd (green) = TCOLOR (green), Dd (blue) = TCOLOR (blue)
(2) When 0 ≦ a_value <15,
Dd (red) ≒ (TCOLOR (red) * a_value) / 16 + Ds (red) * (16-a_value)) / 16
Dd (green) ≈ (TCOLOR (green) * a_value) / 16 + Ds (green) * (16−a_value)) / 16
Dd (blue) ≒ (TCOLOR (blue) * a_value) / 16 + Ds (blue) * (16-a_value)) / 16
The approximate expression may be adopted.
[0027]
FIG. 3 illustrates the anti-alias font command. This command includes a command code (anti-alias font command), ratio data (for example, a_value data) storage address (AADR), character width (TDW), character height (TDH), destination X coordinate (DX), destination Y coordinate (DY) and color data (TCCOLOR) for designating a character color are included. The character width (TDW) and the character height (TDH) are the size of the character that the pattern specified by the ratio data 10 appears, and the relative coordinates of the two or four vertices of the pattern rectangle instead of the height and width. You may specify. The destination X coordinate (DX) and the destination Y coordinate (DY) are storage locations of background data, that is, storage locations of drawing data, and may be specified by memory addresses of two or four vertices of the area. .
[0028]
FIG. 4 illustrates a character drawing command (polygon 4B) as a comparative example. The difference from the anti-alias font command is that binary character data (character font data) is used instead of ratio data (for example, a_value data).
[0029]
FIG. 5 illustrates a character pattern obtained by executing a character drawing command (polygon 4B). Jaggedness is conspicuous at the boundary between the background and the characters.
[0030]
FIG. 6 illustrates a pattern obtained in the frame buffer area FBM by executing the anti-alias font command of FIG. In this anti-alias font command, the state of the boundary between the pattern and the background is determined according to a_value data (ratio data). By blending the unit color (TCOLOR) of the pattern and the background color at the border, the jaggedness at the border becomes inconspicuous, in other words, the border is smooth and the pattern of characters and the like is easy to see. .
[0031]
In order to realize such a blending process, the CPU 1 does not have to burden the blending operation using the background data and the pattern data as far as the drawing processor 3 can draw. On the other hand, the drawing control unit 8 does not have to bear all the calculations. In the read / modify / write operation of the background data, the color data 12 is added to the background data 11 using the ratio data 10 already generated. What is necessary is just to form image data by mixing and writing it back into the frame buffer area FBM.
[0032]
Here, an overall operation for executing the anti-alias font command in the image processing system of FIG. 1 will be described. The CPU 1 writes the command string of the anti-alias font command in the command list area CDM of the local memory 4. It is also possible to write in the main memory 2. Thereafter, the CPU 1 gives an address storing the command string to the drawing control unit 8 to instruct command execution. The drawing control unit 8 loads a command string from the instructed address. When the command code specified in the command string is anti-alias font command, the a_value data is read from the basic data area TXM of the local memory 4 in which the a_value data specified in the command string is stored. Drawing data (background color) is read from the designated frame buffer area FBM on the local memory 4. Then, pixel color mixture calculation is performed using a_value data corresponding to the read drawing data (background data) and the character color (TCOLOR) specified in the command sequence. The data subjected to the color mixture calculation is written back to the drawing data storage location from which the drawing data (background data) has been read.
[0033]
As shown in FIG. 1, a configuration is adopted in which memory 4 allocated to the frame buffer and basic data area is provided separately from the main memory 2 and connected to the graphic processor 3 via a local bus 6 different from the system bus 5. Thus, the frequency at which the memory access by the drawing control unit 8 and the memory access by the CPU 1 compete with each other can be reduced, which contributes to speeding up of data processing. Even in a system including the local memory 4, the command string and ratio data may be used while being held in the main memory 2. In short, the frame buffer may be allocated to the local memory 4 and the work area may be allocated to the main memory 2. In this case, the process of transferring the command sequence and ratio data to the local memory 4 can be omitted.
[0034]
FIG. 7 shows a second example of the image processing system according to the present invention. The difference from FIG. 1 is that a graphic processor 3 having a FIFO buffer 20 is employed. In the configuration of FIG. 7, the FIFO buffer 20 is used for temporary storage of ratio data such as a command string and a_value data. In FIG. 7, the CPU 1 transfers the command string of the anti-alias font command to the FIFO buffer 20, and transfers the a_value data to the FIFO buffer 20 when the storage location of the a_value data is designated in the FIFO buffer 20. The drawing control unit 8 reads a command string from the FIFO buffer 20. When the command code specified in the command string is an anti-alias font command command code (anti-alias font command), the a_value from the area (FIFI buffer 20) in which the a_value data specified in the command string is stored. The data is read, and the drawing data (background data) is read from the drawing data storage location (the frame buffer area FBM of the local memory 4) specified by the command string. Then, pixel color mixture calculation is performed using the a_value data corresponding to the drawing data (background data) and the character color (TCOLOR) specified in the command sequence. The calculation result is written back to the frame buffer area FBM which is the drawing data storage location from which the drawing data (background data) has been read.
[0035]
The FIFO buffer 20 may be a dedicated buffer for the command string. At this time, ratio data represented by a_value data may be stored in the texture area TXM of the local memory 4 or the system memory 2.
[0036]
FIG. 8 shows a third example of the image processing system according to the present invention. The difference from FIG. 1 is that the local memory 4 cannot be used. The frame buffer area FBM, texture area TXM, and command list area CDM are allocated to the main memory 2. In this case, it is necessary to employ a system bus 5 having a large number of parallel bits such that a loss due to contention between the CPU 1 access to the main memory 2 and the graphic processor 3 access can be substantially ignored. If the local memory 4 is not used, the CPU 1 reads the ratio data from, for example, the CD-ROM drive into the main memory 2 of the CPU 1 and transfers the ratio data to the local memory 4 from there, thereby reducing the number of data transfers between the memories. Is possible.
[0037]
FIG. 9 shows a fourth example of the image processing system according to the present invention. In the image processing system having the FIFO buffer 20 described with reference to FIG. 7, the local memory 4 can be eliminated. In this case, the frame buffer area FBM is allocated to the main memory 2, and the command string and ratio data are held in the FIFO buffer 20.
[0038]
FIG. 10 shows a further detailed fifth example of the image processing system according to the present invention. The configuration shown in the figure can be regarded as a more detailed configuration of FIG. A system bus 5 including signal lines for address, data, and control signals includes a CPU (a central processing unit, which may be a microprocessor or a microcomputer) 1, a memory 2, and a graphic, which are representatively shown. A processor 3 is coupled. The memory 2 constitutes a so-called main memory (also referred to as a system memory) used as a work area or a data temporary storage area of the CPU 1. Each of the CPU 1 and the graphic processor 3 is formed on a single semiconductor substrate such as single crystal silicon and separately formed into a semiconductor integrated circuit.
[0039]
When the illustrated data processing system is applied to, for example, a navigation system, the system bus 5 is coupled with an ATAPI (ATA Attachment Packet Interface) interface circuit 23 and a serial interface circuit 24, although not particularly limited thereto. A disk drive unit 25 for accessing map data and the like is connected to the ATAPI interface circuit 23. A position detection circuit 26 such as a GPS (Global Positioning System) receiver is connected to the serial interface circuit 24. A GPS antenna or the like (not shown) is connected to the position detection circuit 26. As is clear from the description of FIG. 1, even if a relatively low-resolution display such as a car navigation system is adopted, the street name and address can be displayed on the map in an easy-to-see manner.
[0040]
When the illustrated data processing system is applied to an Internet television, a modem or a terminal adapter (not shown) is connected to the system bus 5.
[0041]
If a CD-ROM storing the ratio data is attached to the disk drive unit 25, the ratio data can be read into the main memory 2 under the control of the CPU 1. The read ratio data may be transferred to the texture area TXM of the local memory 4 as a unified memory. At this time, the CPU 1 may perform pattern modification processing such as proportional processing on European character fonts on the ratio data reproduced and read by the disk drive unit 25. The texture area TXM of the local memory 4 may store ratio data subjected to pattern modification processing.
[0042]
The CPU 1 writes a display list as a command string in the command list area CDM of the local memory 4. The graphic processor 3 reads and decodes commands in order from the display list of the local memory 4 and performs control for rendering image data and font data in the frame buffer area FBM of the local memory 4 according to the command decoding result. In addition, display control is performed such that pixel data drawn in the frame buffer area FBM of the local memory 4 is read in the scanning direction in synchronization with the display scanning timing.
[0043]
The image data output from the graphic processor 3 in synchronization with the display timing is digital RGB data 30 of 18 bits per pixel, although not particularly limited. The digital RGB data 30 is converted into an analog RGB signal 32 by a D / A converter 31. The digital RGB data 30 can be combined with an external video signal 33 by a mixer (MIX) 34, and the output signal of the mixer 34 is converted into an analog NTSC signal 36 as a television signal compliant with the NTSC standard by a digital video encoder 35. Converted. When the display 37 shown in FIG. 10 is an analog monitor such as VGA (Video Graphics Array) or SVGA (Supper VGA), the analog RGB signal 32 is supplied to the monitor. If the display 37 is a television set monitor, an analog NTSC signal 36 is supplied to the monitor. When the display 37 is a digital monitor of a navigation system, digital RGB signals are directly supplied to the monitor. If the D / A converter 31 is built in the graphic processor 3, it is effective to reduce the number of external terminals (pins) of the graphic processor 3 formed as a semiconductor integrated circuit.
[0044]
FIG. 11 shows an example of the graphic processor 3. The graphic processor 3 includes a rendering unit 40 and a rendering buffer 41 that constitute a drawing control unit, and a display unit 42 and a display buffer unit 43 that constitute a display control unit. The digital RGB data 30 is output to the outside from the display unit 42 via the I / O buffer 44. The interface control with the CPU 1 is performed by the CPU interface unit 45, and the external interface control for the local memory 4 is performed by the memory interface unit 46. The CPU 1 is connected to the I / O buffer 47 via the system bus 5, and the local memory 4 is connected to the I / O buffer 48. CLK0 is an operation reference clock signal of the graphic processor 3, and CLK1 is a display timing signal generically including a vertical synchronization signal, a horizontal synchronization signal, a dot clock signal, and the like. The clock pulse generator (CPG0) 55 divides the clock signal and forms various internal synchronization signals. The clock pulse generator (CPG1) 56 forms an internal timing signal for synchronizing a display control system such as the display unit 42 with the display based on the display timing signal.
[0045]
The rendering buffer unit 41 is a buffer between the external local memory 4 and the rendering unit 40, and read / write data for the frame buffer of the local memory 4, commands read from the local memory 4, and The read ratio data is temporarily stored. The display buffer unit 43 is a buffer between the local memory 4 and the display unit 42, temporarily stores image information read from the frame buffer area of the local memory 4, and passes it to the display unit 42. Further, the display buffer unit 43 has a color palette 43A, and converts image data of 8 bits per pixel into image data of 16 bits per pixel. The CPU interface unit 45 includes a DMA (direct memory access) control circuit 45A and a data format conversion circuit 45B. The data format conversion circuit 45B is a circuit for converting the digital video format YUV (Y is luminance, U / V is color difference component) or the digital video format ΔYUV for navigation system into RGB (red, green, blue) format data.
[0046]
The CPU interface unit 45, the rendering unit 40, the display buffer unit 43, and the I / O buffer 47 share the CPU data bus 50, and an address signal supplied from the CPU 1 to the I / O buffer 47 is transmitted via the CPU address bus 51. The data is supplied to the CPU interface unit 45, the rendering unit 40, and the display buffer unit 43. Thus, the CPU 1 can perform initial setting of control information for the DMA control circuit 45A of the CPU interface unit 45, the rendering unit 40, the color palette 43A of the display buffer unit 43, and the like.
[0047]
The CPU interface unit 45, the rendering buffer unit 41, the display buffer unit 43, and the I / O buffer 48 share a memory data bus 52, and an address signal output from the CPU interface unit 45 or the rendering buffer unit 41 is a memory address bus. The memory interface unit 46 is supplied to the memory interface unit 46 via 53, and based on this, the memory interface unit 46 performs interface control for the local memory 4.
[0048]
The rendering unit 40 reads / writes data from / to the local memory 4 via the rendering buffer unit 41, the memory data bus 52, the memory address bus 53, and the memory interface unit 46. The transfer of image data from the frame buffer area of the local memory 4 to the display buffer unit 43 is not particularly limited, but is performed by the DMA control circuit 45A.
[0049]
In this example, the command list and ratio data can be written to the local memory 4 by the DMA control circuit 45A via the memory address bus 53 and the memory data bus 52 in accordance with the initial setting by the CPU 1.
[0050]
FIG. 12 shows a list of drawing commands executed by the rendering unit 40. The anti-alias font command for performing the blend operation processing is AAFC, which is a kind of 4-vertex plane drawing. The drawing command has a command code and drawing attribute information as illustrated in FIG. The drawing attribute information is information such as the character width (TWD) described with reference to FIG.
[0051]
Although the invention made by the present inventor has been specifically described based on the embodiments, it is needless to say that the present invention is not limited thereto and can be variously modified without departing from the gist thereof.
[0052]
For example, although the unified memory 4 is used in the image processing system, different memories may be allocated as the frame buffer and the texture area. Further, the mixing ratio based on the ratio data is not limited to the three types in the case of FIG. 2, and can be changed as appropriate. Further, the blend calculation method using the ratio data is not limited to the method described based on FIG. 2, and an appropriate method may be adopted from various calculation methods according to the recent error. The ratio data is not limited to a character pattern, but may be a pattern such as a symbol, a figure, or a pattern.
[0053]
In the above description, the case where the invention made mainly by the present inventor is applied to the Internet TV and the navigation system, which are the fields of use behind the invention, has been described. However, the present invention is not limited thereto, and the game machine, The present invention can be widely applied to devices that require image processing, such as mobile phones, particularly electronic devices that include a low-resolution display.
[0054]
【The invention's effect】
The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.
[0055]
That is, the blend ratio between the background and the pattern such as characters is used as data. The CPU issues a specific drawing command for drawing by blending the background color and the pattern colors such as characters. The drawing control unit responding to this command reads the ratio data indicating the degree of color mixture (mixing ratio) from the specified location and reads the background data from the specified drawing data storage location to specify the specified pattern. The color data and the read drawing data are mixed using the information of the mixing ratio corresponding to each pixel, and the mixed data is written back to the drawing data storage location such as the frame buffer. According to the ratio data, the state of the boundary between the pattern and the background is determined, so that the unit color of the pattern and the background color are blended at the boundary, so that the jaggedness in the boundary becomes inconspicuous, and the boundary line Becomes smoother and makes it easier to see patterns such as characters. In order to realize such a blending process, the CPU does not have to burden the blending operation using the background data and the pattern data until the drawing processor can draw as it is. In short, in order to realize the blending process, the CPU only needs to give commands and ratio data, and the burden is small. On the other hand, the drawing unit may not be able to bear all the calculations, and in the read / modify / write operation of the background data, the second data is mixed with the first data (background data) using the ratio data. Then, pattern data is formed and written back to the frame buffer. Therefore, the pattern can be drawn on the background screen in an easy-to-see manner with almost no burden on the CPU.
[0056]
From the above, even if a relatively low-resolution display such as a car navigation system is adopted, the street name and address can be displayed on the map in an easy-to-see manner.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first example of an image processing system according to the present invention centering on a drawing processing system;
FIG. 2 is an explanatory diagram illustrating the contents of pixel color mixture calculation processing;
FIG. 3 is an explanatory diagram illustrating an anti-alias font command.
FIG. 4 is an explanatory diagram illustrating a character drawing command (polygon 4B) as a comparative example.
FIG. 5 is an explanatory diagram illustrating image information obtained by executing a character drawing command (polygon4B).
6 is an explanatory diagram illustrating image information obtained in the frame buffer by executing the anti-alias font command of FIG. 3; FIG.
FIG. 7 is a block diagram showing a second example of the image processing system according to the present invention.
FIG. 8 is a block diagram showing a third example of the image processing system according to the present invention.
FIG. 9 is a block diagram showing a fourth example of the image processing system according to the present invention.
FIG. 10 is a block diagram showing a further detailed fifth example of the image processing system according to the present invention.
FIG. 11 is a block diagram illustrating an example of a graphic processor.
FIG. 12 is an explanatory diagram illustrating a list of drawing commands executed by the rendering unit.
FIG. 13 is an explanatory diagram illustrating an example of a command code of a drawing command.
[Explanation of symbols]
1 CPU
2 Main memory
3 Graphics processor
4 Local memory
FBM frame buffer area
TXM texture area
CDM display list (command string)
5 System bus
6 Local bus
8 Drawing controller
10 Ratio data
11 Background data
12 Color data
13 Image information obtained by pixel color mixture calculation
20 FIFO buffer
25 disk drive unit
26 Position detection circuit
37 display

Claims (13)

A CPU, a drawing control unit, and a memory;
The CPU can generate a plurality of drawing commands to be executed by the drawing control unit,
The drawing control unit can execute the plurality of drawing commands,
The plurality of drawing commands indicate first information indicating a storage destination of character data ratio data, second information indicating the size of the character information, and a storage destination of first drawing information mixed with the character information. A first command including third information,
The drawing control unit, when executing the first command, using the first information and the second information, read the ratio data from the first region of the memory, before Symbol second information and the first The second drawing information generated by reading the first drawing information from the second area of the memory using the three information and performing a predetermined process using the ratio data and the first drawing information. Is stored in the second area in which the read first drawing information is stored.   2. The image processing system according to claim 1, wherein the ratio data is data that defines an edge portion and a center portion of the character information in a plurality of gradations in units of pixels.   3. The image processing system according to claim 1, wherein the ratio data is data for a plurality of pixels corresponding to a font pattern corresponding to a font code on a one-to-one basis. The first drawing information mixed with the character information is background information displayed superimposed on the character information,
The image processing system according to claim 1, wherein the third information is coordinate information indicating the second area in which the first drawing information is stored.   5. The image processing system according to claim 1, wherein the first command further includes color data for designating a color of the character information.   6. The image processing system according to claim 1, further comprising a display control unit that performs control to display on a display connected to the outside of the image processing system using the second drawing information. The image processing system according to claim 1. The image processing system further includes a graphic processor including the drawing control unit, the display control unit, and a memory,
The image processing system according to claim 6, wherein at least the graphic processor is formed on a single semiconductor substrate. Wherein the memory image according to any one of claims 1 to 5, characterized in that the ratio data which is stored in the external memory connected to the outside of the image processing system, for temporarily storing Processing system.   9. The image processing system according to claim 8, wherein the first information is address information indicating a first area of the memory.   4. The image processing system according to claim 3, further comprising: a display control unit that controls the display of the second drawing information stored in the memory by the drawing control unit.   A recording information reproducing unit that reads and reproduces the ratio data from a recording medium on which the ratio data is recorded, and the drawing control unit can use the ratio data reproduced by the recording information reproducing unit. The image processing system according to claim 10.   12. The image processing system according to claim 11, wherein the CPU is capable of performing pattern modification processing on the ratio data reproduced by the recorded information reproduction unit.   6. The image according to claim 5, wherein the predetermined process is a blend process using the ratio data of the character information, the color data of the character information, and the first drawing information. Processing system.

Images