KR0135494B1 - On screen display - Google Patents

Abstract

Disclosed is an OSD character border generation and control apparatus for eliminating character backgrounds using character data, generating character borders, and performing OSD control. According to the present invention has the advantage of eliminating the background of the characters displayed on the screen, to display the image signal in the position of the background to increase the display ratio of the image signal. In addition, by displaying a text border of a certain size for distinguishing the image and the character on the screen has the advantage of easy to distinguish the character. In addition, by displaying a constant size character borders to provide a beautiful display character.

Description

On-Screen Display Character Border Generation and Control

1 is a conventional on-screen display character generation circuit diagram.

2 is a block diagram of an apparatus for generating and controlling an on-screen display text border according to an embodiment of the present invention.

FIG. 3 is a detailed circuit diagram of the latch unit in the configuration of FIG.

FIG. 4 is a detailed circuit diagram of the edge generating unit in the configuration of FIG.

FIG. 5 is a detailed circuit diagram of a character and frame output unit in the configuration of FIG. 2; FIG.

6 is a ROM address data and clock timing diagram in accordance with an embodiment of the present invention.

The present invention relates to an On Screen Display (OSD) control apparatus, in particular, OSD character border generation and control for performing OSD control and character border generation with character data read from a character ROM. Relates to a device.

1 is a conventional on-screen display character generation circuit diagram,

A ROM (10) storing text data for the OSD,

A latch unit 20 for latching character data input from the ROM 10;

Character mixing unit 30 for selectively outputting the video signal and the white peak level signal,

Character background mixing unit 40 for selectively outputting the output signal and the feather level signal of the character mixing unit 30,

The character mixing unit 30 receives the latched character data from the latch unit 20 and outputs character data and inverted character data to the character mixing unit 30 and the character background mixing unit 40 by 1 bit, respectively. ) And a character and background output unit 50 for controlling the output selection of the character background mixing unit 40.

In the above-described configuration, the white peak level means a reference level to be displayed as a character dot on the screen. In addition, the feather star level means a reference level to be displayed as a background dot of a character in a bit map size of a character font on a screen.

Hereinafter, an apparatus for generating and controlling a conventional OSD character border will be described in detail with reference to the above-described configuration of FIG. 1.

First, the ROM 10 receives a control signal and address data input from an OSD controller (not shown) and outputs 16-bit character data (Character Font Data) of 16 X 16 character fonts in the corresponding address. That is, as described above, if the font size of the 16 X 16 character font as a whole, a part indicated by 1 appears in white in the OSD display state, and a part indicated by 0 appears in black in the OSD display state.

The latch unit 20 receives the character data and latches it through a 16-bit bus line. The text and background output unit 50 receives data from the latch unit 20 and outputs text and background data. At this time, the character data of the character and the background output unit 50 is the data that is output the data input from the latch unit 20 as it is, the background data is the data that is inverted output of the data input from the latch unit 20 .

The character mixing unit 30 receives image data and a predetermined white peak level, receives the character data input from the character and the background output unit 50 as a select signal, and inputs the two input signals (image data, white peak level). Outputs optional. That is, in response to the character data, the white peak level signal is displayed on the screen to display the character.

The character background mixing unit 40 receives the output of the character mixing unit 30 and the feather level, and receives the background data input from the character and the background mixing unit 50 as a select signal. Outputting the character mixing section 30, feather level). That is, the feather level signal is displayed on the screen in response to the background data, and the background portion is displayed in a region other than the character portion within the bitmap size of the 16 X 16 character font.

However, as described above, the conventional OSD character border generation and control apparatus has a disadvantage in that the original video signal is blocked by the background data in the bitmap within the font size in which characters are not displayed, so that the image in the screen is not displayed unnecessarily. .

Accordingly, an object of the present invention is to provide an apparatus for generating and controlling an OSD character border which eliminates a text background using text data and generates text borders and controls OSD.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of an apparatus for generating and controlling an OSD character border according to an embodiment of the present invention.

ROM 110 for storing text data for the OSD,

Receives the character data from the ROM 11 by one horizontal line and latches the input data to receive the character data of the horizontal line and the horizontal line of the object to be processed. A latch unit 120 for outputting normally latched character data of data;

The edge generation unit receives the three inverted latched character data and the normal latched character data from the latch unit 120, and generates and outputs a character border data having data increased by a predetermined border width by calculating the input data. 130,

Character mixing unit 150 for selectively outputting the video signal and the white peak level signal,

Character border mixing unit 160 for selectively outputting the output signal and the feather level signal of the character mixing unit 150,

The latching unit 120 receives the normally latched processing target character data and outputs each bit to the character mixing unit 150 as an output selection signal of the video signal and the white peak level signal, and outputs the edge generation unit. Character and edge output unit for receiving the character border data from the 130 and outputs the bit by edge to the character frame mixing unit 160 as a selection signal of the output signal and the feather level signal of the character mixing unit 150 140.

In the above configuration, the ROM 11 stores character data consisting of 16 X 16 character fonts according to an embodiment of the present invention. In addition, in the above-described configuration of the embodiment of the present invention, the frame generation unit generates and outputs character frame data of 18 bits, for example, to generate a frame width of 1 bit.

Here, the white peak level signal is a character display signal for displaying a character in white on a screen, and the feather stab level signal means a character border display signal for displaying a border in black. In one embodiment of the present invention, The white peak level signal and the feather star level signal are used to display the text in white and the border in black.

3 is a detailed circuit diagram of the latch unit 120 in the configuration of FIG.

A first flip-flop that latches 16-bit high-order character data Updata one line above the horizontal line to be processed of the 16 X 16-character font character data inputted from the ROM 11 in synchronization with the first clock signal CLK1. 310,

A second flip-flop 320 which latches the 16-bit character data ProData of the horizontal line to be processed of the 16 X 16 font character data inputted from the ROM 11 in synchronization with the second clock signal CLK2;

A third flip-flop 330 for latching 16-bit sub-character data (DnData b) one line below the horizontal line to be processed of the 16 X 16 font character data inputted from the ROM 110;

A fourth flip that receives the character data ProData of the horizontal line to be processed from the second flip-flop 320 and latches the normal-processed character data ProData and the inverted character data ProData b; Flop 340,

The first flip-flop 310 is composed of a fifth flip-flop 350 that receives the upper character data UpData on one line above the horizontal line to be processed and outputs the inverted upper character data UpData b.

FIG. 4 is a detailed circuit diagram of the edge generating unit 130 in the configuration of FIG. 2, wherein the three input first and second negative logical elements 401 and 416 and the four inputs are formed according to the following logical expressions (1) to (5). First to sixteenth logical logic elements 402 to 415, and first to sixteenth logical multiplication elements 451 to 466.

In the above formulas (1) to (5)

PO: least significant data bit of horizontal line to be processed

P15: Most significant data bit of horizontal line to be processed

Bb: Inverted data of horizontal line to be processed (where b is an integer from 0 to 15)

Ua: Inverted data of the horizontal line higher than the object to be processed

(Where a is an integer from 0 to 15)

Nc: Inverted data of the horizontal line lower than the object to be processed

(Where c is an integer from 0 to 15)

D1-D17: Text Border Data (Back Data)

FIG. 5 is a detailed circuit diagram of a character and frame output unit in the configuration of FIG. 2; FIG.

A value of 0 is added to the top and bottom of the 16-bit character data (Prodata) of the horizontal line to be processed, and 18 bits of data are input in parallel to correspond to the dot clock (Dot CLK) synchronized to the horizontal synchronous clock. First latch means for outputting bit by bit;

Second latch means for receiving 18 bits of character border data (Back Data) input from the edge generation unit 130 in parallel and outputting one bit at a time corresponding to the dot clock synchronized with the horizontal synchronization clock. do.

6 is a ROM address data and clock timing diagram in accordance with an embodiment of the present invention.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the above-described configuration.

First of all, in order to create a border of characters, think about the top, bottom, left and right of the processing point to create the border. That is, the basic requirement for creating a character border is that there is no character data at that point, and that character data must exist at any one of the top, bottom, left and right points. This requires a modification of the ROM addressing. In the case of a general ROM address, the OSD time of one character and the address cycle time coincide. However, in the case of forming the edge, since the ROM data of the top, bottom, left and right are required at the processing target point, it is necessary to have an address cycle period three times faster than the OSD time as shown in FIG.

Hereinafter, the concept of font size 16 X 16 and display size 18 X 18 in the ROM will be briefly described. Consider the character form of 16 X 16 as a whole. A square character data that is framed to form 18 X 18. The OSD reads and processes one direction of the text simultaneously. Therefore, it reads 16 dots, that is, 16 bits of character data, and outputs 18 dots of character signal and character frame signal. Considering the borderless character display, the LSB of the ROM data (D0-D15) is mapped to the 2'nd LSB and the MSB is mapped to the 2'nd MSB. The LSB and MSB are then filled with zeros. Character borders are the same principle. Back data (D0-D17) is generated by a combination logic of 16 bits of upper line data, 16 bits of current line data, and 16 bits of lower line data.

According to the above concept, first, data UpData corresponding to the upper line of the horizontal line to be processed in the ROM address for edge generation is accessed by the address At1. In addition, the data ProData of the processing target line is accessed by At2, and the data DnData added to the lower line of the processing target horizontal line is accessed by At3.

The ROM data accessed by the above operation are latched by the latch clocks CLK1, CLK2, and CLK3 in synchronization with the At1, At2, and At3 cycles in the latch unit 120, respectively. That is, the data UpData of the upper line is latched by CLK1, the data ProData of the processing target line is CLK2, and the data DnData of the lower line is latched by CLK3.

The latched data UpData, ProData, and DnData are finally reclocked and output by CLK3 to generate an edge. At this time, the upper line data UpData is converted and output from the fifth flip-flop 350 to the data of the upper line UpData b inverted in synchronization with CLK3. The lower line data DnData is converted and output from the third flip-flop 330 into the data DnData b of the lower line inverted in synchronization with CLK3. The processing target line data ProData is output from the fourth flip-flop 340 as processing target line data PrData that is normally latched in synchronization with CLK3 and inverted processing target line data ProData b.

The edge generation unit 130 includes data of the upper line UpData b inverted from the latch unit 120, data of the inverted lower line DnData b, normally latched processing target line data ProData, and inverted processing. The target line data ProData b is input to generate and output edge data according to Equation 1-5.

In an embodiment of the present invention, since the font size of one character is assumed to be 16 X 16, in the case of generating a border, the border is formed with a font size of 18 X 18 by increasing one line and one dot on the top, bottom, left and right.

Afterwards, the data of the processing target line normally latched from the latch unit 120, that is, the character data to be displayed on the screen and the BACK data of the edge generator 130 may be a character and edge generator ( 140 are loaded in parallel. Afterwards, the subject line data Pro data, which is normally latched according to a dot clock synchronized with the horizontal synchronization signal from the character and frame generator 140, is input to the character mixer 150 as a selection signal. Character display on the screen is controlled by selectively outputting an image signal and a white peak level signal which are input signals of the character mixing unit 150. In addition, according to the dot clock (Dot CLK) synchronized with the horizontal synchronization signal from the character and frame generation unit 140, the back data (Back data) is input as a selection signal to the character border mixing unit 160, the character border mixing unit An output signal and a feather level signal of the character mixing unit 150, which are input signals of 160, are selectively output. Accordingly, when an output signal of the character mixing unit 150 is selected from the character border mixing unit 160 in response to the back data, the normally latched processing target line data (Prodata) is located at the pixel processing position on the screen. In response to the video signal or the white peak level signal, a character and an image are displayed. However, when the feather star level signal is selected from the character border mixing unit 160, a black character border is displayed at the pixel processing position on the screen.

Therefore, as described above, the present invention has the advantage of eliminating the background of the characters displayed on the screen and displaying the image signal at the position of the background to increase the display ratio of the image signal. In addition, by displaying a text border of a certain size for distinguishing the image and the character on the screen has the advantage of easy to distinguish the character. In addition, by displaying a constant size character borders to provide a beautiful display character.

Claims (4)

In the on-screen display control device, a ROM storing text data for the OSD, and receiving text data from the ROM by one horizontal line and latching the input data to input text data of a horizontal line and a horizontal horizontal line to be processed. And a latch unit for outputting the three reversely latched character data of the character data and the normal latched character data of the character data to be processed, and the three reversely latched character data and the normally latched character data from the latch unit. A border generation unit which receives the input data and generates and outputs a character border data in which data is increased by a predetermined border width, a character mixing unit selectively outputting a video signal and a text display signal, and an output signal of the character mixing unit; And a character border mixing unit for selectively outputting a border display signal; Receives the character data processed normally latched from the latch and outputs each bit to the character mixing unit to output the image signal, the white peak level signal, and the output selection signal, and receives the character border data from the edge generation unit. On-screen display character border generation and control device characterized in that it consists of a character and the edge output unit for outputting the output signal of the character mixing unit and the selection signal of the edge display signal by outputting each bit to the edge mixing unit The apparatus of claim 1, wherein the character data stored in the ROM is character data of a 16 X 16 font. The character border of claim 1, wherein the edge generation unit receives the three reversely latched character data and the normally latched character data from the latch unit, and calculates the input data so that one bit of data is increased by a border width. An on-screen display character border generation and control device for generating and outputting data. The method of claim 2, wherein the edge generating unit receives character data of the three inversely latched 16 X 16 fonts and character data of the normally latched 16 X 16 font from the latch unit, and calculates the input data to 1; An on-screen display character border generation and control device for generating and outputting character border data of an 18 X 18 font in which data is increased by the width of a bit.