JP4466085B2 - Image processing apparatus and decompression writing circuit - Google Patents

Description

  The present invention relates to an image processing device for displaying an image represented by data compressed in a predetermined compression format on a display device, and a decompression writing circuit that can be used as a part of the image processing device.

  2. Description of the Related Art Conventionally, in an image processing apparatus that displays an image indicated by data recorded in a memory on a display device, in order to effectively use the recording capacity of the memory, the compressed data amount is recorded in the memory. It is common to leave.

As this type of image display device, for example, an image display device having a viewer function for continuously displaying image data (image information), and a series of images that are compressed and recorded (stored) When displaying the data sequentially, the image data to be displayed next to the displayed image data is simultaneously decompressed and stored, and the stored image data is displayed based on the next display instruction. An image processing apparatus has been proposed (see Patent Document 1).
Japanese Patent Laid-Open No. 11-341491 (paragraph [0004], FIG. 1)

  However, this image processing apparatus is also configured such that a display processing unit including a single CPU performs a series of processes from reading data from a memory to displaying an image on the display apparatus. Therefore, when an image to be displayed on the display device is configured by each of image elements indicated by a plurality of data, the processing load for decompressing the compressed data increases as the number of image elements constituting the image increases. Will become bigger. Thus, when the display processing unit has to perform other processing simultaneously (in parallel) when the processing load on the display processing unit is large, the start timing of this processing is delayed, The processing time itself becomes longer.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a display processing unit in an image processing apparatus that displays an image indicated by data recorded in a compressed state in a memory on a display device. It is providing the technique for reducing the processing load with respect to.

In order to solve the above-described problem, an image processing apparatus according to claim 1 includes an element memory in which a plurality of element data indicating image elements that can form various images are recorded in a compressed state. The recording device has a recording area associated with the display area of the display device, and data written at a predetermined writing position in the recording area is displayed at a display position in the display area corresponding to the writing position. An image memory serving as data indicating an image to be displayed, and a display processing unit for displaying an image indicated by the element data on the display device by performing processing relating to decompression of element data recorded in the element memory and writing to the image memory And an image processing apparatus. Among these, the display processing unit, for each of one or more image elements constituting a predetermined image, a reading position in an element memory from which element data indicating the image element is to be read, and a display device to display the image element Command selection means for selecting command data capable of specifying a display position in a plurality of command data prepared in advance as corresponding to each of a plurality of types of image elements, and command data selected by the command selection means Is output to the decompression writing processor side.

  The image processing apparatus also includes an element reading unit, an element decompressing unit, and an element writing unit, and decompresses element data recorded in the element memory and writes it to the image memory in response to an instruction from the display processing unit. A decompression and writing processor is provided. Among these, the element reading means reads element data from the reading position specified by the command data input from the display processing unit side. The element decompressing means decompresses the element data read by the element reading means to obtain uncompressed data. Further, the element writing means sets the element data decompressed by the element decompressing means to the writing position in the recording area of the image memory corresponding to the display position based on the display position specified together with the reading position by the command data. Write. Then, for each reading position specified by the command data, reading by the element reading means, decompression by the element decompressing means, and writing by the element writing means are repeatedly performed.

  According to the image processing apparatus configured as described above, the display processing unit simply outputs the command data for instructing the display of the image on the display apparatus to the decompression writing processor. A series of processing until an image is displayed on the display device can be executed by a decompression writing processor provided separately from the display processing unit.

  Therefore, even when the number of image elements constituting an image to be displayed on the display device is large, the processing load on the display processing unit for decompressing the element data does not increase.

  As described above, when displaying an image on the display device, the processing load on the display processing unit can be greatly reduced. Therefore, the display processing unit can perform processing related to image display (command data output). Even if some processing must be performed simultaneously (in parallel), the delay of the start timing of the processing, the length of processing time, and the like can be significantly shortened compared to the conventional case.

  The element data recorded in the element memory is compressed in a predetermined compression format. This compression format is a format that can reduce the data amount of the element data. For example, the specific format is not particularly limited.

  The command output means of the display processing unit is a means for outputting the command data to the decompression write processor side, and outputs (records) the command data to a memory accessible from the decompression write processor side. It may be configured to instruct the decompression writing processor to read the command data later, or may be configured to output the command data directly to the decompression writing processor. The command data output by the command output means may be command data corresponding to an image among those prepared in advance (recorded in the memory), or may be command data generated for each image. Good.

  The element decompression means of the decompression writing processor is means for decompressing (or expanding or decompressing) the element data and returning it to uncompressed data, and is a procedure (shown in a predetermined compression format). What is necessary is just to comprise so that it may decompress | decompress according to an algorithm. Further, if the compression format of the element data can be specified, the decompression may be performed according to the procedure shown in the specified format. In this case, data compressed in different compression formats can be used as element data.

The image processing apparatus according to claim 1 records a plurality of types of color palettes indicating the color distribution in the image element based on the correspondence between the gradation in each pixel of the image element and the attribute of the color to display each pixel. The element memory stores data indicating grayscale image elements as element data. In the display processing unit, the command output means is a pallet memory in which a color palette for determining the color distribution of the image elements is recorded for each of the one or more image elements as well as the reading position and the display position. Data that can specify the recording position is output as command data. In the decompression / writing processor, the element data decompressed by the element decompression means is processed based on the recording position specified together with the reading position by the command data, in the color indicated by the color palette recorded at the recording position. Palette conversion means for converting into data indicating an image element consisting of a distribution is provided, and the element writing means converts the element data converted by the palette conversion means based on the display position specified together with the reading position by the command data, Writing is performed at a writing position in the recording area of the image memory corresponding to the display position.

  According to the image processing apparatus configured as described above, the display processing unit sends data that can specify the recording position of the color palette to the decompression writing processor as command data for instructing display of the image on the display apparatus. The decompression writing processor can execute a series of processes from reading out element data to displaying a color image on the display device.

  In particular, with this configuration, the gray scale image indicated by the element data recorded in the element memory is displayed as a color image expressed by different color distributions depending on the color palette recorded in the palette memory. Can be displayed. Therefore, it is possible to represent the same type of image element with different color distributions without preparing multiple pieces of the same type of element data that differ only in color distribution, and there are many patterns and types of image elements indicating the color distribution. The recording area of the element memory can be saved as much as possible.

  The “color palette” recorded in the palette memory described above is data for determining the color distribution of the image element. For example, the gradation in each pixel of the image element and the display of this pixel are displayed. This is data indicating a correspondence relationship with attributes (hue, saturation, brightness) of colors to be generated.

Further, in the image processing apparatus according to claim 2 , the command output means in the display processing unit displays not only the reading position, the display position, and the recording position but also the color attribute in the image element for each of the one or more image elements. Data capable of specifying the degree of adjustment to be adjusted in accordance with the color attribute of other image elements having the same position is output as command data. In the decompression and writing processor, the attribute of the color in the image element indicated by the element data is adjusted based on the adjustment degree specified by the command data together with the reading position of the element data converted by the palette conversion means. An element conversion means for converting to data is provided, and the element writing means is an image corresponding to the display position based on the display position specified by the command data together with the reading position of the element data converted by the element conversion means. Write to the write position in the recording area of the memory.

  According to the image processing device configured as described above, the display processing unit outputs data that can specify the degree of adjustment to the decompression writing processor side as command data for instructing display of an image on the display device. Thus, the decompression and writing processor can execute a series of processes from reading the element data to displaying a color image in which the color attribute of the image element is changed.

  The “adjustment degree” specified by the command data described above refers to the color attribute (one or more of hue, saturation, and brightness) in the image element, and the color attribute in another image element at the same display position. Is a parameter for adjusting (changing) to match the color of the image element. For example, the mixing ratio for changing the color of the image element to the color of the other image element arranged at the same display position. The parameters shown can be considered. In this case, the color attribute of a specific image element may be adjusted by mixing the color attribute of another image element having the same display position with the ratio indicated by “adjustment degree”.

  Further, as the “adjustment degree”, a parameter indicating a transmission ratio for displaying a specific image element in a state in which the other image element arranged at the same display position is transmitted can be considered. In this case, the color attribute of the specific image element may be adjusted so that the color of the other image element is transmitted through the transmission ratio indicated by the “adjustment degree”.

  By the way, in order to display an image element in the display area of the display device, element data indicating the image element is written in a recording area corresponding to each pixel of the image element. Depending on the position and the configuration of the image memory, the image element may be displayed in an unintended state.

  For example, the image memory is a memory composed of a recording area including a recording area associated with each pixel constituting the display area, and a continuous address is assigned to each recording area, and a constant address width interval. If each of the recording areas divided by is associated with one horizontal line of pixels constituting the display area, the recording areas corresponding to the nth (n is an arbitrary number) lines of the display area are continuous. Thereafter, the recording area for the (n + 1) th line starts immediately from the next address. In this configuration, when an image element is positioned on the end side (or start end side) of the nth line and a part of the image element is projected from the end of the display area, the protruding part is used for address continuity. As a result, data is written in the recording area corresponding to the start end side of the (n + 1) th line (or the end side of the (n-1) th line). For this reason, the image element is displayed in such a manner that the portion that protrudes from the end of the display area wraps around the start end (or end) that should not be displayed.

Therefore, in order to prevent the display in such an unintended state, the following configuration may be employed. For example, when the element writing means in the decompression writing processor writes the element data into the image memory as in the image processing apparatus according to claim 3 , a part of the image element indicated by the element data is a display area. In the case where the data is displayed so as to protrude from the end, the data area of the element data corresponding to the “protruding part” is not written to the image memory.

  With this configuration, even when the image element includes a portion that protrudes from the end of the display area, the data area corresponding to such a portion is not written to the image memory. Can be prevented from being displayed around the start side (or end side) of the line.

In this configuration, there is no particular limitation on how to specify the data area of the element data corresponding to the part protruding from the element writing means. For example, when the command output means in the display processing unit is configured to output not only the reading position and the display position but also command data that can specify the data area corresponding to the “protruding portion” of the element data Then, as described in claim 4 , when the element writing means writes the element data into the image memory, the element writing means protrudes from the data area of the element data specified by the command data together with the reading position and the display position. What is necessary is just to comprise so that the data area corresponding to a part may not be written in an image memory.

According to this configuration, it is possible to identify the “protruding portion” based on the command data output from the display processing unit and prevent writing to the image memory.
According to a fifth aspect of the present invention, there is provided a decompression writing circuit in which a circuit necessary for functioning as the decompression writing processor according to any one of the first to fourth aspects is formed.

According to the decompression / write circuit configured as described above, a part of the decompression / write processor according to any one of claims 1 to 4 can be configured.

An example in which the present invention is applied to a navigation system will be described.
The navigation system 1 includes a CPU 11, a ROM 12, a RAM 13, a VRAM 14, a display unit 15, a liquid crystal display (hereinafter referred to as “LCD”) 16, a hard disk 17, an operation panel 18, a position detection unit 20, a decompression writing processor. 30 and so on.

  The CPU 11 controls the overall operation of the navigation system 1 by sending commands to each component of the navigation system 1 via the bus 19 while recording the processing result in the RAM 13 according to the processing procedure recorded in the ROM 12.

  In the ROM 12, in addition to the processing procedure by the CPU 11, a plurality of compressed element data indicating image elements each capable of constituting an image to be displayed in the display area of the LCD 16, and display of the predetermined image on the LCD 16 are decompressed and written processor 30. Command data to be executed, and a plurality of color palettes indicating different color distributions are recorded. The compressed element data recorded in the ROM 12 indicates gray scale image elements, and is data in which the data amount is compressed in a predetermined compression format. The color palette is data for determining the color distribution of the image element, and the gradation of each pixel of the image element and the attributes (hue, saturation, brightness) of the color on which the pixel is to be displayed. It is the data which shows the corresponding relationship.

  As shown in FIG. 2, the VRAM 14 is composed of recording areas including recording areas associated with w × h pixels (for example, 640 × 480) that constitute the display area of the LCD 16. Assigned addresses (i to j of 0 to n are addresses associated with display areas; i, j ≦ n), and are delimited by a fixed address width (640) Each storage area is associated with pixels for one horizontal line constituting the display area of the LCD 16. Then, the data written at a predetermined writing position in the recording area is displayed (drawn) by the display unit 15 at the display position of the LCD 16 corresponding to the writing position.

The hard disk 17 stores various data necessary for realizing a navigation system function such as map data.
The operation panel 18 includes various input keys for accepting user operations.

  The position detection unit 20 includes a geomagnetic sensor, a gyroscope, a distance sensor, a GPS (global positioning system) receiver, and the like, and is configured to be able to detect the current position of the navigation system 1 (the mounted object). .

The decompression / writing processor 30 operates based on the above-described command data (see “Operation of the decompression / writing processor 30 (FIG. 5)” described later), thereby realizing a function of displaying a predetermined image on the LCD 16. Circuit.
-Command output process by CPU11 Below, the process sequence of the command output process performed by CPU11 is demonstrated based on FIG. This command output processing is performed when an operation that triggers the display of a predetermined image on the LCD 16 by the operation panel 18 or when the predetermined image is displayed on the LCD 16 from the outside (for example, the position detection unit 20 or the like). It is started when the command is received.

First, an image to be displayed on the LCD 16 is specified based on an operation performed on the operation panel 18 or an external command (s110).
Next, command data for causing the decompression / writing processor 30 to display the image specified in the process of s110 on the LCD 16 is read from the plurality of command data recorded in the ROM 12 (s120). In the present embodiment, command data corresponding to each image that may be specified in the process of s110 is recorded in the ROM 12 in advance, and this process of s120 corresponds to the image specified in the process of s110. Read command data from ROM 12.

  This command data is composed of a plurality of commands, and for each of p (1 ≦ p) image elements necessary for constituting a predetermined image, a color palette indicating the color distribution in the image elements is recorded. A recording area in the ROM 12, a recording area (reading position) in the ROM 12 in which compressed element data indicating an image element is recorded, and a recording area (writing position) in the VRAM 14 corresponding to the display position of the LCD 16 on which the image element is to be displayed. This is data that can specify whether or not to mix colors with other image elements displayed at the same display position when displaying image elements, and the mixing ratio of colors when mixing colors with other image elements.

  More specifically, as shown in FIG. 4, a “command number” command indicating the number N of all commands constituting the command data, and a “pallet read” command indicating the recording position (address a) in the ROM 12 of the color palette. The “element display” command related to the display of image elements is arranged in order. This “element display” command is an address b of the recording position of the element data in the ROM 12, an address c of the recording area for each pixel in the VRAM 14; c 1 to ck, and a blend indicating whether or not colors are mixed with other image elements Enable (0: mix, 1: do not mix), blend value (0 to 100%) indicating the mixing ratio when mixing color with other image elements, left side of image element when image element is displayed in display area Is a command indicating a left flag indicating whether or not to protrude from the left end of the display area (0: does not protrude, 1: protrudes). In this embodiment, after the “number of commands” command and the “read palette” command, an “element display” command is arranged until an image element whose color distribution in the image element is to be changed, and “read palette” is displayed. After the command is inserted, the “element display” command is repeated until the image element whose color distribution is to be changed again is repeated until the number N of commands indicated by the “command number” command is reached. Yes.

  Next, the command data read in the process of s120 is recorded in the RAM 13 (s130). In this way, as shown in FIG. 5, the command data in the ROM 12 is recorded in the RAM 13 (see arrow a in FIG. 5).

  Next, the decompression / writing processor 30 is caused to start an operation relating to the display of the image specified in the process of s110 (s140). In this process, start command data for starting an operation relating to image display is output to the decompression / write processor 30 (see arrow b in FIG. 5). The decompression / writing processor 30 that has input the start command data operates in accordance with an operation procedure described later (FIG. 5), and then notifies that the image is displayed on the LCD 16 (see arrow s in FIG. 5). Therefore, the CPU 11 can recognize that the image specified in the process of s110 is displayed on the LCD 16 by this notification (see an arrow t in FIG. 5).

Next, it waits until it receives notification from the decompression writing processor 30 that an image has been displayed (s150: NO).
When the notification is received in the process of s150 (s150: YES), the command data recorded in the RAM 13 is deleted in the process of s130 (s160), and this command output process is terminated.
-Operation procedure of decompression writing processor 30 Hereinafter, the operation procedure of the decompression writing processor 30 will be described with reference to FIG.

  The decompression writing processor 30 includes an interface unit (hereinafter referred to as “I / F”) 31, a setting register 32, a command processing unit 33, an acquisition unit 34, a decompression unit 35, a conversion unit 36, a mixing unit 37, and a writing unit. 38, and operates while inputting / outputting data to / from the outside via the I / F 31.

The decompression / writing processor 30 starts its operation in response to a command from the CPU 11. This command is the start command data output by the CPU 11 in the process of s140 in FIG. 3, and the CPU 11 writes the start command data into the setting register 32 (arrow b) to start the operation related to the image display. Command.
(1) Acquisition of command data (see arrows cf in FIG. 5)
The command processing unit 33 monitors the contents of the setting register 32 (arrow c), and instructs the acquisition unit 34 to read command data from the RAM 13 when the start command data is written by the CPU 11 (arrow d). ). Here, the command data to be read from the RAM 13 is recorded by the CPU 11 in the process of s130 in FIG. 3 (see arrow a).

  Receiving this command, the acquisition unit 34 reads command data from the RAM 13 (arrow e), and passes this command data to the command processing unit 33 (arrow f). The command processing unit 33 stores the command data in a built-in register for each command, and thereafter performs operations in order according to the respective commands.

When performing the operations in order according to each command, if the command is “number of commands”, this command is only a command for causing the command processing unit 33 to recognize the number of all commands constituting the command data. No action is taken for this command.
(2) Operation for color palette (see arrows d and g in FIG. 5)
When performing the operation in order according to each command, if the command is “pallet reading”, the command processing unit 33 instructs the acquisition unit 34 to read the color palette from the ROM 12 (arrow d). Here, the color palette to be read from the ROM 12 is recorded at the recording position indicated by the “read palette” command.

Receiving this instruction, the acquisition unit 34 reads the color palette from the ROM 12 (arrow g), and passes this color palette to the conversion unit 36 (arrow h). The conversion unit 36 has a register capable of storing (setting) a color palette. By storing the color palette input from the acquisition unit 34 in the register, the conversion unit 36 indicates the data input from the decompression unit 35 hereinafter. Can be converted into a color distribution according to a stored color palette.
(3) Operation 1 for compressed element data (see arrows d and i to o in FIG. 5)
When performing the operation in order according to each command, when the command is “element display” and the command is a command indicating that the color is not mixed with other image elements, the command processing unit 33 displays the mixing ratio “ The ratio data indicating “0%” (that is, the colors are not mixed) is passed to the mixing unit 37 (arrow i), and the left flag indicated by the “element display” command and the writing position data indicating the writing position are written to the writing unit. 38 (arrow j), the acquisition unit 34 is instructed to read the compressed element data from the ROM 12 (arrow d). Here, the compressed element data to be read from the ROM 12 is recorded in the recording area (reading position) indicated by the “element display” command.

Receiving this command, the acquisition unit 34 reads the compressed element data from the ROM 12 (arrow k), and passes this compressed element data to the decompressing unit 35 (arrow l).
The decompressing unit 35 that has input the compressed element data converts the compressed element data into decompressed element data obtained by decompressing (or expanding or expanding), and then passes the decompressed element data to the converting unit 36 (arrow m). The decompressing unit 35 is a configuration for obtaining decompressed data obtained by decompressing compressed data compressed in a predetermined compression format.

  As described above, the conversion unit 36 to which the decompression element data is input has the decompression element data indicating the image element obtained by converting the decompression element data input from the decompression unit 35 into a color distribution according to the stored color palette; Then, the decompressed element data is transferred to the mixing unit 37 (arrow n).

  The mixing unit 37 that has input the decompressed element data passes the decompressed element data as it is to the writing unit 38 (arrow o). The mixing unit 37 has a register capable of storing the ratio data. Only when the mixing ratio indicated by the ratio data stored in this register is “0%”, the converted decompressed element data is written as it is. The data is passed to the insertion unit 38. In this operation, since the ratio data indicating the mixing ratio “0%” at the arrow i is input (and stored in the register), the converted decompressed element data is directly passed to the writing unit 38.

  Then, the writing unit 38 to which the decompression element data is input writes the decompression element data input from the mixing unit 37 into the VRAM 14 as described above (arrow p). The writing unit 38 has a register capable of storing write position data. By storing the write position data in this register, data input from the mixing unit 37 is stored in the VRAM 14 thereafter. It is possible to write in the write position indicated by the write position data in the recording area. Here, since the write position data is input (and stored in the register) from the command processing unit 33 at the arrow j, the write position (address) of each of the pixels constituting the image element indicated by the write position data. In any one of c1 to ck), the corresponding portion of the decompressed element data is sequentially written for each line.

  However, the writing unit 38 does not write the decompression element data for the writing position determined as the address of the writing position indicated by the writing position data being the specific writing position. In the writing position determined as the “specific writing position”, for example, the address of the writing position indicated by the writing position data is an address other than the display area of the LCD 16 (that is, the address is i There is a writing position that is smaller and larger than j. Such a writing position is not displayed because there is no display area corresponding to the LCD 16 even if decompression element data is written (see the wavy line portion 100a of the image element 100 in FIG. 6). The decompression element data is not written.

  In addition, the writing position determined as “specific writing position” includes the address width (640) of the display area at the start address (i) of the display area in the recording area for each line in which the decompression element data is to be written. There is a writing position that is an address deviating from the head address and the last address for each line obtained by integrating. Specifically, if “1” is set in the left flag, the writing position is an address smaller than the head address for each line, and “0” is set in the left flag. If it is, the write position is an address larger than the final address for each line. If the decompression element data is written as it is in the recording area including such a writing position, a part of the image element indicated by the decompression element data is protruded from the end side of the display area. Due to the continuity of the addresses assigned to the recording area in the VRAM 14, it is displayed at the opposite end in the display area (see the wavy lines 200a and 300a of the image elements 200 and 300 in FIG. 6). For this reason, the decompression element data is not written so that a part of the image element may not be displayed.

In this manner, the decompressed element data written in the VRAM 14 is drawn on the display area of the LCD 16 as a color image element by the display unit 15.
(4) Operation 2 for compressed element data (see arrows d and i to r in FIG. 5)
When performing the operation in order according to each command, when the command is “element display” and the command is a command for mixing colors with other image elements, first, the command processing unit 33 executes the VRAM 14. Is commanded to the acquisition unit 34 (arrow d). The decompressed element data to be read at this time is recorded at the writing position indicated by the “element display” command.

  Receiving this command, the acquisition unit 34 reads the decompression element data from the VRAM 14 (arrow q), and passes this decompression element data to the mixing unit 37 (arrow r). The mixing unit 37 has a register that can store the decompression element data in addition to the register that can store the ratio data, and stores the decompression element data input from the acquisition unit 34 in the register, so that The decompression element data input from the conversion unit 36 is converted into data indicating an image element in a state where the color of the image element indicated by this data is mixed with the color of the image element indicated by the stored decompression element data. Can do. At this time, the color of the image element indicated by the decompressed element data input from the conversion unit 36 is mixed with the color of the image element indicated by the stored decompressed element data at the mixing ratio indicated by the stored ratio data.

  Further, the command processing unit 33 instructs the acquisition unit 34 to read the decompression element data, and then passes the ratio data indicating the mixing ratio indicated by the “element display” command to the mixing unit 37 (arrow i). After the writing position data indicating the writing position indicated by the “display” command is transferred to the writing unit 38 (arrow j), the acquisition unit 34 is instructed to read the compressed element data from the ROM 12 (arrow d).

Receiving this command, the acquisition unit 34 reads the compressed element data from the ROM 12 (arrow k), and passes this compressed element data to the decompressing unit 35 (arrow l).
The decompressing unit 35 that has input the compressed element data uses decompressed compressed element data to obtain decompressed element data, and then passes the decompressed element data to the converting unit 36 (arrow m).

  As described above, the conversion unit 36 to which the decompression element data is input has the decompression element data indicating the image element obtained by converting the decompression element data input from the decompression unit 35 into a color distribution according to the stored color palette; After that, the converted decompressed element data is passed to the mixing unit 37 (arrow n).

  As described above, the mixing unit 37 to which the decompression element data is input converts the decompression element data input from the southern part 36 of the image element indicated by the decompression element data in which the color of the image element indicated by this data is stored. After being converted into decompression element data indicating image elements mixed at the mixing ratio indicated by the color and the stored ratio data, the decompression element data is passed to the mixing unit 37 (arrow o).

Then, the writing unit 38 to which the decompression element data is input writes the decompression element data input from the mixing unit 37 into the VRAM 14 as described above (arrow p).
(5) End of operation (arrows s, t)
In this way, the command processing unit 33 repeats the operations (2) to (4) to perform operations for all commands, thereby displaying an image composed of one or more image elements on the LCD 16, and then ends the operation. Information data for informing the effect is written to the setting register (arrow s). Here, the CPU 11 monitors the contents of the setting register 32, and detects that the notification data has been written to the setting register 32 (arrow t), whereby the operation related to the image display by the decompression writing processor 30 is performed. It can be recognized that the image has been displayed on the LCD 16 after finishing (FIG. 3; s150).

[effect]
According to the navigation system 1 configured as described above, the CPU 11 records command data for instructing display of an image on the LCD 16 in the RAM 13 and then outputs start command data to the decompression writing processor 30 ( A decompression writing processor provided separately from the CPU 11 for a series of processes from reading compressed element data to displaying an image (an image made up of one or more image elements) on the LCD 16 only by writing to the setting register 32 30 can be executed.

  Therefore, even when the number of image elements constituting an image to be displayed on the LCD 16 is large, the processing load on the CPU 11 for decompressing the compressed element data does not increase.

  As described above, when displaying an image on the LCD 16, the processing load on the CPU 11 can be greatly reduced. Therefore, the CPU 11 performs some processing in addition to processing related to image display (recording of command data in the RAM 13). Even if it becomes a situation that must be performed simultaneously (in parallel), the delay of the start timing of this processing, the length of the processing time, etc. can be significantly shortened compared to the conventional case.

  Further, the gray scale image element indicated by the compressed element data recorded in the ROM 12 can be displayed on the LCD 16 as a color image element expressed by a color distribution based on the color palette recorded in the ROM 12. For this reason, the same type of image element can be expressed with different color distributions without preparing multiple pieces of the same type of compressed element data that differ only in color distribution, and the pattern indicating the color distribution and the type of image element are different. As the number increases, the recording area of the ROM 12 can be saved.

  Further, since the command data instructs to convert the gray scale image element into the color image element in the color palette read by the “palette read” command, the decompression writing processor 30 thereby A series of processing from reading the compressed element data to displaying a color image on the LCD 16 can be executed.

  In addition, among the commands constituting the command data, the “element display” command can be used to instruct that the color of the image element is mixed with other image elements that display the color of the image element at the same display position. The decompression and writing processor 30 executes a series of processes from reading the compressed element data to displaying the color image on the LCD 16 in a state where the colors of the plurality of image elements displayed at the same display position are mixed. can do.

  The writing unit 38 does not write the corresponding part (data area) of the decompressed element data corresponding to such a part when the image element includes a part that protrudes from the end of the display area. It is possible to prevent the element from being displayed around the start side (or end side) of the line. At this time, whether or not the image element has a portion that protrudes from the end of the display area can be determined (specified) based on the addresses c1 to ck and the left flag specified by the element display command.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to said specific embodiment, It can implement with a various form besides this.

  For example, in the above-described embodiment, the navigation system 1 to which the image processing apparatus of the present invention is applied has been exemplified. However, the image processing apparatus of the present invention displays an image indicated by data recorded in a memory on a display device. Any device other than the navigation system can be applied.

  The compressed element data recorded in the ROM 12 is compressed in a predetermined compression format. If this compression format is a format that can be reduced by compressing the data amount, the specific data The specific format is not particularly limited, and a known compression format may be employed, or a unique compression format may be employed.

  In the above embodiment, the CPU 11 instructs the decompression / write processor 30 to read command data from the RAM 13 (writes the start command data to the setting register 32), whereby the command data is sent to the decompression / write processor 30 itself. The thing comprised so that it might acquire was illustrated. However, the CPU 11 writes the command data read in the process of s120 to the setting register 32 of the decompression / write processor 30 instead of the processes of s130 and s140 in FIG. The write processor 30 is configured so that when command data is written to the setting register 32, the command data is stored in the built-in register for each command, and thereafter, the operation is performed in accordance with each command. Also good.

  In the above embodiment, a plurality of types of command data are recorded in advance in the ROM 12, and the configuration is such that the corresponding command data is read out in the processing of s120 in FIG. However, the command data may be generated every time the processing of s120 in FIG. 3 is performed without recording the command data in the ROM 12. Specifically, based on the image specified in the processing of s110, one or more image elements necessary for composing the image, the color distribution in these image elements, and the image elements are displayed on the display area of the LCD 16 In this configuration, it is determined how to arrange the command data, and command data including a plurality of commands is generated based on the determined items.

  Moreover, in the said embodiment, what decompress | decompressed part 35 of the decompression write processor 30 illustrated what was comprised so that only the compression element data compressed by the predetermined compression format might be decompress | decompressed. However, the decompressing unit 35 may be configured to identify the compression format of the compressed element data input from the acquisition unit 34 and decompress the compressed element data according to the procedure (algorithm) indicated in the identified format. In this case, data compressed in different compression formats can be used as the compressed element data.

  In the above embodiment, among the commands constituting the command data, the “element display” command is a command indicating a mixing ratio when mixing colors with other image elements, and the mixing unit 37 of the decompression writing processor 30. However, according to this “element display” command, the image element is configured to perform processing for mixing the color of an image element with the color of another image element. However, the “element display” command may indicate a transmission ratio for transmitting other image elements in a region where the display position overlaps with other image elements. In this case, the command processing unit 33 passes the ratio data indicating the transmission ratio at the arrow j in FIG. 5 to the mixing unit 37, so that the mixing unit 37 assigns the color attribute of the specific image element to another image element. The color may be adjusted so as to be in a state of being transmitted by the transmission ratio indicated by the ratio data.

[Correspondence with the present invention]
In the present embodiment, the navigation system 1 is an image processing apparatus according to the present invention. The CPU 11 is a display processing unit in the present invention, the ROM 12 is an element memory and a palette memory in the present invention, the RAM 13 is an element memory in the present invention, the VRAM 14 is an image memory in the present invention, and the LCD 16 is in the present invention. In the display device.

  In the decompression writing processor 30, the acquisition unit 34 and the command processing unit 33 are element reading means in the present invention, the decompression unit 35 is an element decompressing means in the present invention, and the writing unit 38 and the command processing unit 33 are The element writing unit in the present invention, the conversion unit 36 and the command processing unit 33 are palette conversion units in the present invention, and the mixing unit 37 and the command processing unit 33 are element conversion units in the present invention.

  Further, the processing of s130 in FIG. 3 is command output means in the present invention.

The block diagram which shows the structure of the navigation system in this embodiment. The figure which shows the relationship between the recording area of VRAM, and the display area of LCD Flow chart showing processing procedure of command output processing Diagram showing command data structure and command types Functional block diagram showing operation of decompression writing processor The figure which shows the state which wrote the image element in the recording area of VRAM

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Navigation system, 11 ... CPU, 12 ... ROM, 13 ... RAM, 14 ... VRAM, 15 ... Display part, 16 ... Liquid crystal display, 17 ... Hard disk , 18 ... Operation panel, 19 ... Bus, 20 ... Position detection unit, 30 ... Decompression writing processor, 31 ... Interface unit, 32 ... Setting register, 33 ... Command Processing part 34 ... Acquisition part 35 ... Decompression part 36 ... Conversion part 37 ... Mixing part 38 ... Writing part.

Claims (5)

An element memory in which a plurality of element data indicating image elements that can form various images are recorded in a compressed state in a predetermined compression format;
There is a recording area associated with the display area of the display device, and data written at a predetermined writing position in the recording area is displayed at a display position in the display area corresponding to the writing position. An image memory serving as data indicating an image
A display processing unit for displaying an image indicated by the element data on a display device by performing processing relating to decompression of element data recorded in the element memory and writing to the image memory. There,
In response to a command from the display processing unit, a decompression writing processor is provided for decompressing the element data recorded in the element memory and writing to the image memory,
The display processing unit
For each of one or more image elements constituting a predetermined image, a command capable of specifying a reading position in the element memory from which element data indicating the image element is to be read and a display position in a display device on which the image element is to be displayed Command selection means for selecting data from a plurality of command data prepared in advance as corresponding to each of a plurality of types of images;
Command output means for outputting the command data selected by the command selection means to the decompression writing processor is provided,
The decompression write processor
Element reading means for reading the element data from the reading position specified by the command data input from the display processing unit side;
Element decompression means for decompressing the element data read by the element readout means into uncompressed data;
An element document for writing the element data decompressed by the element decompression means to the writing position in the recording area of the image memory corresponding to the display position based on the display position specified together with the reading position by the command data And is provided with,
Each of the reading positions specified by the command data is configured to repeat reading by the element reading means, thawing by the element thawing means, and writing by the element writing means ,
further,
A palette memory in which a plurality of color palettes indicating the color distribution in the image element are recorded according to the correspondence between the gradation in each pixel of the image element and the attribute of the color to be displayed on each pixel;
In the element memory, data indicating a gray scale image element is recorded as the element data,
In the display processing unit,
The command output means records in the palette memory in which not only the readout position and the display position but also a color palette for determining the color distribution of the image element is recorded for each of the one or more image elements. Output data that can specify the position as command data,
In the decompression writing processor,
Based on the recording position specified together with the reading position by the command data, the element data decompressed by the element decompressing means is an image having a color distribution indicated by the color palette recorded at the recording position. Pallet conversion means for converting into data indicating elements is provided,
In the recording area of the image memory corresponding to the display position, the element writing means converts the element data converted by the pallet conversion means based on the display position specified together with the reading position by the command data. An image processing apparatus for writing to the writing position . In the display processing unit,
The command output means includes, for each of the one or more image elements, not only the reading position, the display position, and the recording position, but also the other image elements having the same display position with respect to color attributes in the image element. Output data that can specify the degree of adjustment to be adjusted according to the color attribute in the command data,
In the decompression writing processor,
The element data converted by the palette converting means is converted into data in which the color attribute of the image element indicated by the element data is adjusted based on the adjustment degree specified together with the reading position by the command data. Element conversion means are provided,
In the recording area of the image memory corresponding to the display position, the element writing means converts the element data converted by the element conversion means based on the display position specified together with the reading position by the command data. The image processing apparatus according to claim 1 , wherein writing is performed at a writing position. In the decompression writing processor,
The element writing means corresponds to a protruding portion when a part of an image element indicated by the element data is displayed protruding from an end of the display area when writing the element data to the image memory. the data area of the element data to the image processing apparatus according to claim 1 or claim 2, characterized in that not write to the image memory. In the display processing unit,
The command output means outputs not only the reading position and the display position, but also command data that can specify a data area corresponding to the protruding portion of the element data,
In the decompression writing processor,
When the element writing means writes the element data into the image memory, the data area corresponding to the protruding portion specified together with the reading position and the display position by the command data in the data area of the element data The image processing apparatus according to claim 3 , wherein writing to the image memory is not performed. Thawing write circuit composed is formed circuitry required to function as a decompression write processor according to any one of claims 1 to 4.

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