JP2006251072A - Display controller, display device, display control method, display control program, and computer readable recording medium recorded with display control program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display controller capable of sufficiently reducing the amount of data to be outputted, and to provide a display device, a display control method, a display control program and a computer readable recording medium in which the display control program is recorded. <P>SOLUTION: When there is even one pixel of black display in a line currently displayed, a monitoring part 22 turns an A flag 31 on for the line, if data is written even to one pixel in the line, turns a B flag on and if data other than white display is written even to one pixel in the line, turns a C flag 33 on. An operation part 23 sets a D flag 34 indicating whether or not the line is for ouputting data to a display driver by a logical operation. A drawing signal generation circuit 4 outputs data for display based on the D flag 34. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display control device for controlling a display device, particularly a liquid crystal display device having a memory property for a display image, a display device, a display control method, a display control program, and a computer-readable recording medium on which the display control program is recorded. About.

  When displaying a moving image or the like in an image display apparatus, the amount of display data to be rewritten is made as small as possible to improve the efficiency of the display data rewriting process.

  For example, the continuous image display device described in Patent Document 1 stores display data before rewriting and display data after rewriting in a working memory, and compares the display data in a region that has changed. Data is stored in the image memory. In the display control methods and display devices described in Patent Documents 2 and 3, the means for rewriting the display data of the entire screen and the means for rewriting a part of the screen are switched depending on conditions.

  In the ferroelectric liquid crystal display device, the ferroelectric liquid crystal itself has bistability, and the display panel itself including the ferroelectric liquid crystal has a memory property. When the display data is rewritten, only the changed cylinder part of the screen is partially scanned, and the part that is not changed is displayed using the memory property. Therefore, it is not necessary to refresh the entire screen, and the screen does not flicker at all, so that power can be saved and display quality can be improved.

  The ferroelectric liquid crystal display devices described in Patent Documents 4 and 5 have a flag corresponding to the scanning line of the display, and when display data is written in the display memory, the ferroelectric liquid crystal display device corresponds to the scanning line on which writing has been performed. Set the flag. When the display data is transferred from the display memory to the display device, the flag is referred to, and the data of the scanning line corresponding to the set flag is transferred.

Japanese Unexamined Patent Publication No. 63-198095 Japanese Patent Laid-Open No. 2-235094 Japanese Patent Laid-Open No. 3-109524 Japanese Patent No. 2652220 Japanese Patent No. 2652221

  As described above, the conventional technology attempts to improve the efficiency of the rewriting process by reducing the transfer amount of display data to be rewritten, but it is not sufficient.

  An object of the present invention is to provide a display control device, a display device, a display control method, a display control program, and a computer-readable recording medium on which the display control program is recorded that can sufficiently reduce the amount of data to be output. is there.

The present invention is a display control device for writing input image data to a display memory and outputting display data based on the image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the image data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The image data includes pixel data indicating display and non-display for each pixel,
The flag is
A first flag indicating the state of the image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of the image data to be written to the display memory;
The monitoring unit
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether the display line includes a pixel in which pixel data indicating display is written in the display memory, and writing to the third flag;
The output unit is a display control device that creates and outputs the display data based on the first to third flags.

Further, the present invention is a display control device for writing input image data to a display memory and outputting display data based on the image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the image data in a flag;
An arithmetic unit for writing the state of the display data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The image data includes pixel data indicating display and non-display for each pixel,
The flag is
A first flag indicating the state of the image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of image data to be written to the display memory;
A fourth flag indicating the state of the display data,
The monitoring unit
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether the display line includes a pixel in which pixel data indicating display is written in the display memory, and writing to the third flag;
The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and writes the display line to the fourth flag.
The output unit is a display control device that creates and outputs the display data based on the fourth flag.

  In the logic operation of the arithmetic unit, the display line including the pixel written in the display memory is a display line including the display pixel, or the pixel data indicating the display is written in the display memory. It is characterized by determining whether the display line includes.

Further, in the present invention, the arithmetic unit performs a logical operation based on the first to third flags and writes a fifth flag indicating a display line including display pixels,
The monitoring unit may determine whether to include display pixels based on the fifth flag and rewrite the first flag.

The present invention also provides a display control device for writing input color image data to a display memory and outputting display data based on the color image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input color image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the color image data in a flag;
A gradation storage unit for storing background color information;
An output unit for outputting display data to the liquid crystal display panel;
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
The flag is
A first flag indicating the state of the color image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of color image data to be written to the display memory;
The monitoring unit
Determining whether the display line includes a pixel indicating display other than a background color, and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than a background color is written in the display memory, and writing to the third flag;
The output unit is a display control device that creates and outputs the display data based on the first to third flags.

The present invention also provides a display control device for writing input color image data to a display memory and outputting display data based on the color image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input color image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the color image data in a flag;
An arithmetic unit for writing the state of the display data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
The flag is
A first flag indicating the state of the color image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of the color image data written to the display memory;
A fourth flag indicating the state of the display data,
The monitoring unit
Determining whether the display line includes a pixel indicating display other than a background color, and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than a background color is written in the display memory, and writing to the third flag;
The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and writes the display line to a fourth flag.
The output unit is a display control device that creates and outputs the display data based on the fourth flag.

  Further, according to the present invention, in the logical operation of the arithmetic unit, the display line including the pixel written in the display memory includes a pixel other than the background color, or pixel data indicating display other than the background color is included in the display memory. It is characterized in that it is determined whether or not the display line includes a pixel written in.

Further, in the present invention, the arithmetic unit performs a logical operation based on the first to third flags and writes a fifth flag indicating a display line including pixels other than the background color,
The monitoring unit determines whether to include a pixel other than a background color based on the fifth flag, and rewrites the first flag.

The present invention also provides the display control device described above,
A display device comprising: a liquid crystal display panel for displaying display data output from the display control device.

Further, according to the present invention, the controller writes the input image data into the display memory, and the output unit outputs the display data based on the image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel. Display control method to output to
The image data includes pixel data indicating display and non-display for each pixel,
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data is written in the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display is written in the display memory and writing to the third flag;
In the display control method, the output unit generates and outputs the display data based on the first to third flags.

According to the present invention, the control unit writes the input color image data into the display memory, and the output unit displays the color image data written in the display memory and display data based on the flag corresponding to the display line of the liquid crystal display panel. A display control method for outputting to a display panel,
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
Determining whether the display line includes a pixel indicating display in addition to the background color and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data is written in the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than the background color is written in the display memory, and writing to the third flag;
In the display control method, the output unit generates and outputs the display data based on the first to third flags.

  The present invention also provides a display control program that causes a computer to execute the above display control method.

  Further, the present invention is a computer-readable recording medium recording a display control program that causes a computer to execute the above-described display control method.

  According to the present invention, the control unit writes the input image data into the display memory, and the output unit displays the display data based on the image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel. A display control device that outputs to a panel.

  The monitoring unit determines whether or not the display line includes a pixel indicating display, and if it includes, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display is written in the display memory. If it is included, the third flag is set to ON.

  Based on the first to third flags set in this way, the display data is created and output.

  Based on the first to third flags, for example, a display line including a pixel in which pixel data is written in the display memory, the display line including the display pixel, or pixel data indicating display in the display memory. It can be determined whether the display line includes written pixels, and the output data amount can be reduced by outputting only pixel data of such a display line.

  According to the invention, the control unit writes the input image data into the display memory, and the output unit displays the image data written in the display memory and the display data based on the flag corresponding to the display line of the liquid crystal display panel. A display control device that outputs to a display panel.

  The monitoring unit determines whether or not the display line includes a pixel indicating display, and if it includes, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display is written in the display memory. If it is included, the third flag is set to ON.

  The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and sets the fourth flag to be on for the display line to be output.

  Based on the fourth flag set in this way, the display data is created and output.

  Based on the fourth flag, for example, a display line including a pixel in which pixel data is written in the display memory, and a display line including a display pixel or pixel data indicating display is written in the display memory It can be determined whether the display line includes pixels, and the output data amount can be reduced by outputting only the pixel data of such a display line. Further, since the fourth flag is set by a logical operation, it is not necessary to store image data for determining data output.

Further, according to the present invention, the logical operation of the arithmetic unit is performed such that a display line including a pixel written in the display memory is a display line including a display pixel, or pixel data indicating display is written in the display memory. It is determined whether the display line includes the selected pixel.
Thereby, it is possible to easily determine a display line that requires output of display data.

  According to the invention, the arithmetic unit performs a logical operation based on the first to third flags, and writes it in a fifth flag indicating a display line including display pixels. The monitoring unit determines whether the display line includes display pixels based on the fifth flag, and rewrites the first flag.

  Thereby, since the first flag is rewritten based on the logical operation, it is not necessary to store the image data currently displayed on the liquid crystal display panel.

  According to the invention, the control unit writes the input color image data into the display memory, and the display unit based on the color image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel is output to the output unit. Is a display control device that outputs to a liquid crystal display panel.

  The monitoring unit determines whether or not the display line includes a pixel indicating display in addition to the background color, and if it includes, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display other than the background color is written in the display memory. If it is included, the third flag is set to ON.

  Based on the first to third flags set in this way, the display data is created and output.

  Based on the first to third flags, for example, a display line including pixels in which pixel data is written in the display memory, pixel data other than a background color or pixel data indicating a display other than a background color is A display line including pixels written in the display memory can be determined, and the amount of data to be output can be reduced by outputting only pixel data of such a display line.

  According to the invention, the control unit writes the input color image data into the display memory, and the display unit based on the color image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel is output to the output unit. Is a display control device that outputs to a liquid crystal display panel.

  The monitoring unit determines whether or not the display line includes a pixel indicating display in addition to the background color, and if it includes, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display other than the background color is written in the display memory. If it is included, the third flag is set to ON.

  The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and sets the fourth flag to be on for the display line to be output.

  Based on the fourth flag set in this way, the display data is created and output.

  Based on the fourth flag, for example, a display line including pixels in which pixel data is written in the display memory, pixel data including pixels other than the background color or indicating a display other than the background color is displayed on the display The display line including the pixel written in the memory can be determined, and the amount of data to be output can be reduced by outputting only the pixel data of such a display line. Further, since the fourth flag is set by a logical operation, it is not necessary to store image data for determining data output.

According to the invention, the logical operation of the arithmetic unit is a pixel data indicating that the display line including the pixel written in the display memory is a display line including a pixel other than the background color or a display other than the background color. Is a display line including pixels written in the display memory.
Thereby, it is possible to easily determine a display line that requires output of display data.

  According to the invention, the arithmetic unit performs a logical operation based on the first to third flags, and writes the fifth arithmetic flag indicating a display line including pixels other than the background color. The monitoring unit determines whether a pixel other than the background color is included based on the fifth flag, and rewrites the first flag.

  Thereby, since the first flag is rewritten based on the logical operation, it is not necessary to store the image data currently displayed on the liquid crystal display panel.

  According to the invention, there is provided a display device comprising the display control device and a liquid crystal display panel for displaying display data output from the display control device.

  Thereby, since the amount of display data is reduced, the processing time for displaying the image data can be shortened.

According to the invention, the control unit writes the input image data into the display memory, and the output unit outputs the display data based on the image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel. This is a display control method for outputting to a display panel.
The image data includes pixel data indicating display or non-display for each pixel.

  It is determined whether or not the display line includes a pixel indicating display. If it is included, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display is written in the display memory. If it is included, the third flag is set to ON.

  Based on the first to third flags set in this way, the display data is created and output.

  Based on the first to third flags, for example, a display line including a pixel in which pixel data is written in the display memory, the display line including the display pixel, or pixel data indicating display in the display memory. It can be determined whether the display line includes written pixels, and the output data amount can be reduced by outputting only pixel data of such a display line.

  According to the invention, the control unit writes the input color image data to the display memory, and the output unit outputs the color image data written to the display memory and the display data based on the flag corresponding to the display line of the liquid crystal display panel. Is a display control method for outputting to a liquid crystal display panel.

  The color image data includes pixel data indicating at least a color or a gradation value for each pixel.

  It is determined whether or not the display line includes a pixel indicating display in addition to the background color. If it is included, the first flag is set to ON. In addition, it is determined whether or not the display line includes a pixel in which pixel data is written in the display memory. If it is included, the second flag is set to ON. Further, it is determined whether or not the display line includes a pixel in which pixel data indicating display other than the background color is written in the display memory. If it is included, the third flag is set to ON.

  Based on the first to third flags set in this way, the display data is created and output.

  Based on the first to third flags, for example, a display line including a pixel in which pixel data is written in the display memory, a display line including a pixel other than the background color, or a display other than the background color is indicated. It is possible to determine whether the pixel data is a display line including pixels written in the display memory. By outputting only pixel data of such a display line, the amount of data to be output can be reduced.

  Further, according to the present invention, it is possible to provide a display control program for causing a computer to function as the display control device and a computer-readable recording medium on which the display control program is recorded.

FIG. 1 is a block diagram showing a configuration of a display control apparatus 1 according to an embodiment of the present invention.
The display control apparatus 1 receives monochrome binary image data created by application software or the like from a CPU (Central Processing Unit) and writes it in a VRAM (Video Random Access Memory) 5. Display data is created based on the image data written in the VRAM 5, and the display data is output to a display driver of a liquid crystal display having a display image memory property such as ferroelectricity.
The display control device 1 includes a sequencer 2, a flag 3, and a drawing signal generation circuit 4.

  The sequencer 2 includes a work memory 21, a monitoring unit 22, and a calculation unit 23. When image data (address data and pixel data) and a write signal are received from the CPU, the sequencer 2 temporarily stores the image data in the work memory, and the VRAM 5 Is a control unit that outputs a write signal and writes image data.

  The flag 3 includes an A flag 31, a B flag 32, a C flag 33, and a D flag 34. Each flag is set to ON or OFF for each line of display data.

  The A flag 31 is a first flag and is a flag indicating the current display state of the liquid crystal display. If even one pixel in the line is black, the flag is turned on for that line. If everything in the line is white or there is no data, the flag is turned off.

  The B flag 32 is a second flag and is a flag indicating a line in which data is written in the VRAM 5 based on image data input from the CPU. If data is written even in one pixel in the line, the flag is turned on, and if data is not written in all the pixels in the line, the flag is turned off.

  The C flag 33 is a third flag, and is a flag indicating whether the data written in the VRAM 5 is data other than white display. The flag is turned on if data other than white display is written even in one pixel in the line, and the flag is turned off if white display data is written in all the pixels in the line.

  The D flag 34 is a fourth flag and indicates whether or not the line is a line for outputting data to the display driver. When the B flag is on and either the A flag or the C flag is on, display data for the line is output. In other words, if the line has a write to the VRAM 5 and the current data includes black display data or the written data includes black display data, the flag is turned on. If there is a line where writing is present and all the current data is displayed in white and all the written data is also displayed in white, the data will not change in white display despite the writing. Since it is substantially unnecessary to output display data for the line to the display driver, the flag is turned off.

  The monitoring unit 22 of the sequencer 2 monitors the image data received from the CPU, and sets the B flag 32 and the C flag 33 according to the above flag setting conditions.

  FIG. 2 is a diagram showing the relationship between the storage area of the VRAM 5 and the flag 3. Here, it is assumed that the liquid crystal display panel 6 has a configuration of 640 × 480 pixels.

  The VRAM 5 stores binary pixel data at each address based on image data input from the CPU. For example, when data is written between addresses “0000H” and “004FH”, data is written in the first line, so the monitoring unit 22 corresponds to the first line of the B flag 32. Set the flag on. If the written data is black display data, the flag corresponding to the first line of the C flag 33 is set to ON.

  Based on the set state of the A flag 31, the B flag 32, and the C flag 33, the calculation unit 23 determines whether the D flag 34 is turned on or off by logical operation.

  Assuming that A to D for identifying each flag represent true or false (1, 0) of each flag, D can be calculated by an arithmetic expression D = B AND (A OR C).

  According to this calculation formula, the calculation unit 23 is a display line including a pixel in which pixel data is written in the VRAM 5, and is a display line including a black display pixel or a pixel in which pixel data indicating black display is written in the VRAM 5. Is written to the D flag 34.

  In addition, when the display data reflecting the D flag 34 is output to the display driver, the calculation unit 23 calculates a value A ′ indicating the display state after rewriting by a logical operation and calculates an A ′ flag (not shown) 5 flag) is temporarily written, and the A flag 31 is rewritten with the calculation result as a new A. A ′ can be calculated by the arithmetic expression A ′ = (NOTB AND A) OR (B AND C).

  The drawing signal generation circuit 4 is an output unit that creates display data from the image data written in the VRAM 5 with reference to the D flag 34 and outputs the display data to the display driver.

3 and 4 are diagrams showing examples of flag sets.
First, it is assumed that the display screen 10 on which nothing is displayed is rewritten to the display screen 11 on which characters are generated. In addition, the dotted line in drawing represents the positional relationship of a display line, and shall not be displayed actually.

  Since nothing is displayed on the display screen, all the A flags 31 are set to OFF. In order to display a hiragana such as the display screen 11, when image data is input from the CPU, the sequencer 2 writes the image data into the VRAM 5. At this time, the monitoring unit 22 detects a line in which data is written based on the address data, and sets the B flag 32. Here, the hiragana from “Aiueo” to “Tatetsuto” and the data including the line spacing are written.

  Further, the monitoring unit 22 detects a line including pixels whose written data is black display data, and sets the C flag 33. As described above, data is also written between the lines, but since the data between the lines is white display data, the C flag 33 does not set the flag for the line corresponding to the line.

  When the flag setting for the C flag 33 is completed, the arithmetic unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and sets the operation result in the D flag 34.

  When the D flag 34 is set, the drawing signal generation circuit 4 creates display data from the image data written in the VRAM 5 with reference to the D flag 34 and outputs the display data to the display driver.

  The computing unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and changes the A flag 31 with the operation result A 'as a new A.

  Following FIG. 3, it is assumed that the display screen 11 on which hiragana is displayed is rewritten to the display screen 12 on which alphabets are displayed.

  A ′ calculated in FIG. 3 is set in the A flag 31. When image data is input from the CPU to display the alphabet as in the display screen 12, the sequencer 2 writes the image data into the VRAM 5. At this time, the monitoring unit 22 detects a line in which data is written based on the address data, and sets the B flag 32. Here, the alphabet from “ABCDE” to “PQRST” and the data including the space between the lines are written.

  Further, the monitoring unit 22 detects a line including pixels whose written data is black display data, and sets the C flag 33. As described above, data is also written between the lines, but since the data between the lines is white display data, the C flag 33 does not set the flag for the line corresponding to the line.

  When the flag setting for the C flag 33 is completed, the arithmetic unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and sets the operation result in the D flag 34.

  When the D flag 34 is set, the drawing signal generation circuit 4 creates display data from the image data written in the VRAM 5 with reference to the D flag 34 and outputs the display data to the display driver.

  The computing unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and changes the A flag 31 with the operation result A 'as a new A.

  FIG. 5 is a diagram illustrating another example of the flag set. In addition, the dotted line in drawing represents the positional relationship of a display line, and shall not be displayed actually.

  In this example, dictionary application software (hereinafter abbreviated as “dictionary application”) creates image data. The display screens 13 and 14 show a part of the screen that is actually displayed. The dictionary application is an English-Japanese dictionary application, and displays a word starting with “paper” and idiom candidates as shown in the display screen 13 by a search process. When “paper” is selected by the user from the candidates, the English-Japanese dictionary application tries to display the meaning of the selected “paper” as shown in the display screen 14. At this time, the display of “paper” is not changed, and other candidates below “paper case” are displayed while being shifted to the lower side of the screen.

  In addition, English characters are displayed with 12 dots and Chinese characters are displayed with 16 dots. The line spacing is 2 dots, and when the meaning is displayed, the line spacing at the bottom of the screen is increased.

  The A flag 31 is set to ON for all lines other than the line spacing based on the candidate display screen 13. When the image data is input from the CPU, the sequencer 2 writes the image data into the VRAM 5 in order to display the meaning of “paper” like the display screen 14. At this time, the monitoring unit 22 detects a line in which data is written based on the address data, and sets the B flag 32. Here, since the “paper” display does not change, a flag is set on the line below the “paper” display portion.

  Further, the monitoring unit 22 detects a line including pixels whose written data is black display data, and sets the C flag 33. Like the display screen 14, a line including pixels that are black display data is a line that displays the meaning of “paper” and a line that displays other candidates shifted downward.

  When the flag setting for the C flag 33 is completed, the arithmetic unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and sets the operation result in the D flag 34.

  When the D flag 34 is set, the drawing signal generation circuit 4 creates display data from the image data written in the VRAM 5 with reference to the D flag 34 and outputs the display data to the display driver.

  The computing unit 23 performs a logical operation based on the A flag 31, the B flag 32, and the C flag 33, and changes the A flag 31 with the operation result A 'as a new A.

FIG. 6 is a flowchart showing display control processing by the display control apparatus 1.
In step S1, initialization is performed, and all the flags of the A flag 31 to the D flag 34 are set to OFF (0).

  In step S <b> 2, the sequencer 2 receives image data created by application software or the like from the CPU and writes it into the VRAM 5.

  In step S <b> 3, the monitoring unit 22 detects a line on which writing has been performed based on the address data, and sets a flag corresponding to the line detected by the B flag 32 to ON.

  In step S4, the monitoring unit 22 detects a line including a pixel of black display data among the written lines based on the address data and the pixel data, and a flag corresponding to the line detected by the C flag 33 Set to ON.

  In step S5, it is determined whether a display update command is input from the CPU. If it is input, the process proceeds to step S6. If not input, the process returns to step S2.

  In step S <b> 6, the arithmetic unit 23 performs a logical operation with an arithmetic expression D = B AND (A OR C) based on the A flag 31, the B flag 32, and the C flag 33.

  In step S 7, the calculation result is set in the D flag 34.

  In step S <b> 8, the drawing signal generation circuit 4 refers to the D flag 34 and creates display data from the image data written in the VRAM 5.

  In step S9, the drawing signal generation circuit 4 outputs the created display data to the display driver.

  In step S10, the arithmetic unit 23 performs a logical operation with an arithmetic expression A ′ = (NOTB AND A) OR (B AND C) based on the A flag 31, the B flag 32, and the C flag 33, and the operation result A ′. And the A flag 31 is changed.

  In step S11, all the B flag 32, C flag 33, and D flag 34 are set to OFF (0).

  In step S12, it is determined whether there is a next page to be displayed. If there is a next page, the process returns to step S2, and if not, the process ends.

  As described above, it is not necessary to output pixel data whose display content remains white before and after rewriting, and only the pixel data whose display content changes is output, thereby reducing the amount of data to be output. be able to.

  FIG. 7 is a block diagram showing a configuration of a display control device 41 according to another embodiment of the present invention. The display control device 1 shown in FIG. 1 controls the display of monochrome binary image data, while the display control device 41 controls the display of color multivalued image data. Since the configuration of the display control device 41 is similar to the configuration of the display control device 1 shown in FIG. 1, only different portions will be described, and portions that perform similar operations will be described with the same reference numerals. Is omitted.

  The sequencer 42 includes a gradation storage unit 43 in addition to the work memory 21, the monitoring unit 22, and the calculation unit 23. The gradation storage unit 43 stores background color color information, gradation values, and the like.

  The flag 44 has an E flag 35 instead of the C flag 33. The E flag 35 is a flag indicating whether the data written in the VRAM 5 is data other than the background color display. The flag is turned on if data other than the background color display is written even in one pixel in the line, and the flag is turned off if background color display data is written in all the pixels in the line.

  The monitoring unit 22 of the sequencer 42 monitors the image data received from the CPU, and sets the E flag 35 according to the above flag setting condition with reference to the background color information stored in the gradation storage unit 43. .

FIG. 8 is a flowchart showing display control processing by the display control device 41.
In step S21, initialization is performed, and all the A flag 31, B flag 32, D flag 34, and E flag 35 are set to off (0).

  In step S <b> 22, the sequencer 42 receives image data created by application software or the like from the CPU and writes it into the VRAM 5.

  In step S23, the monitoring unit 22 detects a line on which writing has been performed based on the address data, and sets a flag corresponding to the line detected by the B flag 32 to ON.

  In step S24, the monitoring unit 22 detects a line including pixels of data other than the background color display among the written lines based on the address data and the pixel data, and sets the line detected by the E flag 35 as the detected line. Set the corresponding flag on.

  In step S25, it is determined whether a display update command is input from the CPU. If entered, the process proceeds to step S26, and if not entered, the process returns to step S22.

In step S <b> 26, the calculation unit 23 performs a logical operation with an arithmetic expression D = B AND (A OR E) based on the A flag 31, the B flag 32, and the E flag 35.
In step S27, the calculation result is set in the D flag 34.

  In step S <b> 28, the drawing signal generation circuit 4 refers to the D flag 34 and creates display data from the image data written in the VRAM 5.

  In step S29, the drawing signal generation circuit 4 outputs the created display data to the display driver.

  In step S30, the arithmetic unit 23 performs a logical operation with an arithmetic expression A ′ = (NOTB AND A) OR (B AND E) based on the A flag 31, the B flag 32, and the E flag 35, and the operation result A ′. And the A flag 31 is changed.

  In step S31, all the B flag 32, C flag 33, and E flag 35 are set to OFF (0).

  In step S32, it is determined whether there is a next page to be displayed. If there is a next page, the process returns to step S22, and if not, the process ends.

  In the above description, the monitoring unit, the calculation unit, the flag, and the like have been described as being included in the sequencer. However, the configuration is not limited to this, and may be independent from each other as long as they are included in the display control device.

  Another embodiment of the present invention is a display control program for causing a computer to function as a display control device, and a computer-readable recording medium on which the display control program is recorded. Accordingly, the display control program and the recording medium on which the display control program is recorded can be provided in a portable manner.

  A display control program is executed by reading the recording medium by a program reading device provided in a printer or a computer system.

  The computer system includes these input means, a computer that executes display control by loading a predetermined program, a display device such as a CRT display / liquid crystal display that displays the processing results of the computer, and the processing results of the computer It is composed of a printer that outputs the data to paper. Furthermore, a LAN (Local Area Network) interface as communication means for connecting to a server or the like via a network is provided.

  The recording medium is not limited to be read by the program reading device, and may be a microcomputer memory, for example, a ROM. The recorded program may be accessed and executed by the microprocessor, or the program read from the recording medium may be downloaded to the program storage area of the microcomputer and executed. This download function is assumed to be provided in the microcomputer in advance.

Specific examples of recording media include tape systems such as magnetic tapes and cassette tapes, magnetic disks such as flexible disks and hard disks, and CD-ROMs (Compact Disc-
Optical discs such as Read Only Memory (MO) (Magneto Optical) disc / MD (Mini Disc) / DVD (Digital Versatile Disc), IC (Integrated Circuit) cards (including memory cards) / cards such as optical cards Or mask ROM, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically
Erasable Programmable Read Only Memory) and a medium that carries a fixed program including a semiconductor memory such as a flash ROM.

  In the present embodiment, the computer may have a system configuration that can be connected to a communication network including the Internet, and the image processing program may be downloaded via the communication network. In the case of downloading a program from the communication network in this way, the download function may be provided in advance in the computer or installed from another recording medium. The download program may be executed through a user interface, or may be a program that periodically downloads a program from a predetermined URL (Uniform Resource Locater).

  Although the present invention has been described above as a display control device, the present invention is not limited to this, and a display device including a VRAM and a liquid crystal display panel may be used.

It is a block diagram which shows the structure of the display control apparatus 1 which is one Embodiment of this invention. 4 is a diagram illustrating a relationship between a storage area of a VRAM 5 and a flag 3. FIG. It is a figure which shows the example of a flag set. It is a figure which shows the example of a flag set. It is a figure which shows the other example of a flag set. 4 is a flowchart showing display control processing by the display control device 1. It is a block diagram which shows the structure of the display control apparatus 41 which is other embodiment of this invention. 5 is a flowchart showing display control processing by the display control device 41.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,41 Display control device 2,42 Sequencer 3,44 Flag 4 Drawing signal generation circuit 5 VRAM
21 Work Memory 22 Monitoring Unit 23 Calculation Unit 31 A Flag 32 B Flag 33 C Flag 34 D Flag 35 E Flag

Claims (13)

A display control device for writing input image data to a display memory and outputting display data based on the image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the image data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The image data includes pixel data indicating display and non-display for each pixel,
The flag is
A first flag indicating the state of the image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of the image data to be written to the display memory;
The monitoring unit
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether the display line includes a pixel in which pixel data indicating display is written in the display memory, and writing to the third flag;
The display control device, wherein the output unit creates and outputs the display data based on the first to third flags. A display control device for writing input image data to a display memory and outputting display data based on the image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the image data in a flag;
An arithmetic unit for writing the state of the display data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The image data includes pixel data indicating display and non-display for each pixel,
The flag is
A first flag indicating the state of the image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of image data to be written to the display memory;
A fourth flag indicating the state of the display data,
The monitoring unit
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether the display line includes a pixel in which pixel data indicating display is written in the display memory, and writing to the third flag;
The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and writes the display line to a fourth flag.
The display control device, wherein the output unit creates and outputs the display data based on the fourth flag.   The logical operation of the arithmetic unit is whether a display line including pixels written in the display memory is a display line including display pixels or a display line including pixels in which pixel data indicating display is written in the display memory. The display control apparatus according to claim 2, wherein: The arithmetic unit performs a logical operation based on the first to third flags and writes a fifth flag indicating a display line including display pixels,
The display control apparatus according to claim 2, wherein the monitoring unit determines whether to include display pixels based on the fifth flag, and rewrites the first flag. A display control device for writing input color image data to a display memory and outputting display data based on the color image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input color image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the color image data in a flag;
A gradation storage unit for storing background color information;
An output unit for outputting display data to the liquid crystal display panel;
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
The flag is
A first flag indicating the state of the color image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of color image data to be written to the display memory;
The monitoring unit
Determining whether the display line includes a pixel indicating display other than a background color, and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than a background color is written in the display memory, and writing to the third flag;
The display control device, wherein the output unit creates and outputs the display data based on the first to third flags. A display control device for writing input color image data to a display memory and outputting display data based on the color image data written to the display memory to a liquid crystal display panel,
A control unit for writing the input color image data into a display memory;
A flag corresponding to a display line of the liquid crystal display panel;
A monitoring unit for writing the state of the color image data in a flag;
An arithmetic unit for writing the state of the display data in a flag;
An output unit for outputting display data to the liquid crystal display panel;
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
The flag is
A first flag indicating the state of the color image data currently displayed on the liquid crystal display panel;
Second and third flags indicating the state of the color image data written to the display memory;
A fourth flag indicating the state of the display data,
The monitoring unit
Determining whether the display line includes a pixel indicating display other than a background color, and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data has been written to the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than a background color is written in the display memory, and writing to the third flag;
The arithmetic unit performs a logical operation based on the first to third flags, determines a display line to which pixel data is to be output, and writes the display line to a fourth flag.
The display control device, wherein the output unit creates and outputs the display data based on the fourth flag.   The logical operation of the arithmetic unit is a pixel in which a display line including a pixel written in the display memory includes a pixel other than a background color or pixel data indicating a display other than a background color is written in the display memory. The display control apparatus according to claim 6, wherein the display line includes a display line. The arithmetic unit performs a logical operation based on the first to third flags, writes in a fifth flag indicating a display line including pixels other than the background color,
The display control apparatus according to claim 6, wherein the monitoring unit determines whether or not a pixel other than a background color is included based on the fifth flag, and rewrites the first flag. A display control device according to any one of claims 1, 2, 5, 6;
A display device comprising: a liquid crystal display panel for displaying display data output from the display control device. Display control in which the control unit writes the input image data to the display memory, and the output unit outputs the display data based on the image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel to the liquid crystal display panel A method,
The image data includes pixel data indicating display and non-display for each pixel,
Determining whether the display line includes a pixel indicating display and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data is written in the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display is written in the display memory and writing to the third flag;
The display control method, wherein the output unit creates and outputs the display data based on the first to third flags. The control unit writes the input color image data to the display memory, and the output unit outputs the display data based on the color image data written in the display memory and the flag corresponding to the display line of the liquid crystal display panel to the liquid crystal display panel. A display control method,
The color image data includes pixel data indicating at least a color or a gradation value for each pixel,
Determining whether the display line includes a pixel indicating display in addition to the background color and writing to the first flag;
Determining whether the display line includes a pixel in which pixel data is written in the display memory and writing to the second flag;
Determining whether or not the display line includes a pixel in which pixel data indicating display other than the background color is written in the display memory, and writing to the third flag;
The display control method, wherein the output unit creates and outputs the display data based on the first to third flags.   A display control program for causing a computer to execute the display control method according to claim 10 or 11.   A computer-readable recording medium having a display control program recorded thereon, which causes a computer to execute the display control method according to claim 10 or 11.

Images