KR19980035451A - Generation Circuit and Method of On-Screen Display in Imaging System - Google Patents

Abstract

end. The technical field to which the invention described in the claims belongs

Imaging system

I. The technical problem that the invention is trying to solve

Prints a specific pattern or image as the background of the on-screen display.

All. Summary of the Solution of the Invention

Background memory for storing the data for the background and a background control unit for reading and outputting the background data from the background memory when a predetermined synchronization signal is applied, the characters on the on-screen display is displayed The wallpaper data is output to the wallpaper that does not exist.

la. Important uses of the invention

You can print various patterns or images as wallpaper on the on-screen display.

Description

Generation Circuit and Method of On-Screen Display in Imaging System

The present invention relates to a circuit and method for generating an on-screen display in an imaging system, and more particularly to a circuit and a method for generating a background of an on-screen display.

In general, an on-screen display (hereinafter referred to as an OSD) in an image system displays a state of an image system such as a channel number or intensity of a screen on a monitor screen. The OSD, which is displayed on the monitor screen while the keys are operated, allows the user to check the functions such as time adjustment and schedule recording while watching the monitor screen when using the remote control.

1 is a block diagram of an on-screen display generating circuit in a conventional video system, and includes a font memory 100 and an OSD control unit 110.

Referring to FIG. 1, the font memory 100 stores fonts of letters to be displayed on a screen. The OSD controller 110 reads bitmap data of characters to be displayed on the screen from the font memory 100 and outputs them to the screen in response to an applied synchronization signal.

In the conventional video system, the OSD is output as a monochromatic (mainly blue) background screen, so the output screen of the OSD is very monotonous. Therefore, it is easy for the user to get tired of the monochrome background screen representing the conventional OSD.

It is therefore an object of the present invention to provide a circuit and method for generating an OSD in an imaging system.

Another object of the present invention is to provide a circuit and method for generating a background screen for displaying OSD text in an image system.

Still another object of the present invention is to provide a circuit and a method for providing various patterns or image screens as a background screen of an OSD in an image system.

According to an aspect of the present invention, there is provided a background memory for storing data on a background screen, and a background screen controller for reading and outputting data on the background screen from a background memory when a predetermined synchronization signal is applied. It is characterized in that for outputting the background screen data to the background screen is not displayed characters of the on-screen display.

1 is a block diagram of an on-screen display generating circuit in a conventional video system.

2 is a block diagram of a background screen generation circuit of an on-screen display according to an embodiment of the present invention.

3 is a block diagram illustrating a background screen generation circuit of an on-screen display according to a specific embodiment of the present invention.

4 is a view showing characters and background screen of the on-screen display according to an embodiment of the present invention.

5 illustrates a screen of an on screen display according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings according to a specific embodiment of the present invention will be described in detail.

FIG. 2 is a block diagram of a background screen generation circuit of an on-screen display according to an embodiment of the present invention, and includes a font memory 100, an OSD controller 110, a background memory 200, a background screen controller 210, and a multiplexer 220. do.

1 and 2, the fond memory 100 and the OSD controller 110 have the same circuit configuration and operation as those shown in FIG. 1. The background memory 200 stores various background data according to an exemplary embodiment of the present invention. The capacity of the background memory 200 is determined according to the amount of data of the background image to be stored. That is, the capacity of the background memory 200 depends on the size of the background screen, and also the number of colors for outputting the color screen. In addition, the background memory 200 may be a ROM, and one of various background images may be selected by downloading from the outside using a RAM to use various background images. The OSD controller 110 reads data on the characters of the OSD from the font memory 100 in response to an applied synchronization signal and outputs the data of the OSD to the multiplexer 220. Meanwhile, the background controller 210 controls the background memory 200 to read data about the background screen in response to an applied synchronization signal. The background controller 210 converts the background data into a background OSD signal and outputs the background OSD signal to the multiplexer 220. In other words, the background screen controller 210 reads data of the background screen from the background memory 200 in response to an applied synchronization signal, converts the background data into the background OSD signal, and outputs the converted background OSD signal to the multiplexer 220. The multiplexer 220 receives the data on the OSD text output from the OSD control unit 110 and the data on the background screen output from the background control unit 210 and multiplexes the data. In the present invention, the multiplexer 220 receives the data for the background screen and the data for the OSD text, and if the data for the text of the OSD overlaps with the data for the wallpaper, only the data for the text of the OSD is duplicated. Output That is, data of letters of the OSD has a higher priority than data of the background screen. Therefore, the data of the text of the OSD is not affected by the data of the background screen.

3 is a block diagram of an on-screen display generating circuit according to a specific embodiment of the present invention, in which a font memory 100, an OSD controller 110, a background memory 200, a multiplexer 220, an M counter 302, an N counter 304 and an address are shown. Generator 306.

4 is a diagram illustrating characters and a background screen of an on-screen display according to an embodiment of the present invention, wherein the number of pixels constituting one background screen and one character is 8x8, and each block is as follows.

Referring to Figure 4, (a) block is a block representing a background screen according to an embodiment of the present invention. (b) A block is a block representing a bitmap of on-screen display letters according to an embodiment of the present invention. Block (c) is a block in which the on-screen display letters are displayed on a background screen according to an embodiment of the present invention, in which (a) block and (b) block are combined. When the data on the text and the data on the background are combined, the data on the text of the OSD has a higher priority than the data on the background. Therefore, as shown in the block (c), when data on the text of the OSD overlaps with data on the background screen, only data on the text of the OSD is output.

5 is a diagram illustrating a screen for outputting an on-screen display according to an embodiment of the present invention.

Referring to FIG. 5, the size of the background screen for the on-screen display in the embodiment of the present invention is 8 × 8, and one background screen is composed of eight dots vertically and eight dots horizontally. If the vertical or horizontal size of the monitor screen outputting the background screen is larger than the background screen, the background screen is repeatedly displayed on the monitor screen as shown in FIG. 5. Further, when the vertical or horizontal size of the monitor screen outputting the background screen is smaller than the background screen, only a part of the background screen appears on the monitor screen.

3 to 5, the operation of the background screen generating circuit of the on-screen display according to the embodiment of the present invention will be described. It is assumed that the size of the background screen according to the embodiment of the present invention is M × N. If M or N is smaller than the vertical or horizontal size of the monitor screen outputting the background screen, the background screen is repeatedly displayed on the monitor screen. Further, when M or N is larger than the vertical or horizontal size of the monitor screen for outputting the background screen, only a part of the background screen appears on the monitor screen. The M counter 302 is cleared when the vertical synchronization signal is applied, and outputs a signal counted from 0 to M-1 to the address generator 306. That is, the M counter 302 counts from 0 to M-1 so as to display M dots vertically, and is cleared by the vertical synchronization signal to repeat the count operation. On the other hand, the N counter 304 is cleared when the horizontal synchronization signal is applied, and outputs a signal counted from 0 to N-1 to the address generator 306. That is, the N counter 304 counts from 0 to N-1 so as to display N dots horizontally, and is cleared by the horizontal synchronous signal to repeat the count operation. The address generator 306 receives a signal output from the M counter 302 and a signal output from the N counter 304, converts the signal into an address, and outputs the converted address to the background memory 200. That is, the address generator 306 generates an address using the signals output from the counters 302 and 304 and controls the background memory 200 to output the data of the background screen. In other words, the address generator 306 receives m output from the M counter 302 and n output from the N counter 304 and generates an address using an equation of m × N + n. Here, M and N may be set to a multiplier of 2 so that m values may be mapped to upper addresses and n values may be mapped to lower addresses without using a multiplier or an adder. For example, as shown in FIG. 4, when a block having a size of 8x8 is used as a wallpaper, M values and N values are 8, respectively, and 3 bits are output. 6 bits and 64 addresses can be generated by mapping a 3 bit n value to a lower address. The background memory 200 receives an address signal output from the address generator 306 and outputs data corresponding to the address to the multiplexer 220. The multiplexer 220 receives OSD data on the background screen output from the background memory 200 and OSD data on the text output from the OSD controller 110 and outputs OSD data selected by the background selection signal. That is, the multiplexer 220 receives the OSD data for the background screen and the OSD data for the text and outputs the text OSD data preferentially in accordance with the applied background selection signal. Therefore, since the data of the text of the OSD is not affected by the data of the background screen, the text of the OSD is correctly output to the background screen.

As described above, the present invention can use various patterns, logos or image screens as the background screen of the OSD in the video system.

Claims (4)

In the generation circuit of the on-screen display in the imaging system, Wallpaper memory that stores data about the wallpaper, A background screen controller which performs a control operation of reading data on the background screen from the background memory in response to a predetermined synchronization signal and outputting a background OSD signal; A memory for fonts that stores data about characters on the on-screen display, An OSD controller for performing a control operation of reading data on characters of the on-screen display from the font memory in response to the synchronization signal and outputting a character OSD signal; And a multiplexer configured to receive the background OSD signal and the text OSD signal and multiplex the outputted OSD signal in response to a background selection signal applied thereto. The method of claim 1, The background screen controller may include: a first counter that counts the number of vertical dots of the background screen in response to a vertical synchronization signal, and outputs a signal corresponding thereto; A second counter that counts the number of horizontal dots of the background screen in response to a horizontal synchronization signal, and outputs a signal corresponding thereto; And an address generator for generating a predetermined address from the signals output from the first counter and the second counter. In the on-screen display generating method in the imaging system, And outputting data on the background screen of the on-screen display and data on the characters for the on-screen display in response to a predetermined background selection signal. The method of claim 3, And data on letters for the on-screen display have a higher priority than data on a background screen of the on-screen display.