KR19990034136A - Character information contour correction apparatus and method of TV receiver - Google Patents

Abstract

The present invention relates to an apparatus and method for correcting character information of a TV receiver for solving the deterioration of the resolution and focus of the character information in a display element such as a large TV, especially when using a TV as a monitor of a computer. will be.

Conventionally, when a large TV or a projection TV is used as a computer monitor, the resolution of the text information is reduced and the focus is deteriorated, so that the text information cannot be displayed clearly, especially since the contour compensator compensates the outline of the entire image. There is a problem that it is difficult to use for a monitor of a computer requiring a resolution, and it is difficult to solve that the focus of the TV receiver is lower than that of the monitor.

The present invention extracts the character region from the horizontal character region by separating the horizontal character region and the general image region of the image signal so that the resolution and focus of the character information as described above can be clearly displayed, and the horizontal / vertical line width of the extracted character region. By configuring the character information contour processing unit to compensate for the deterioration of the focus, so that the clear character information is displayed.

Description

Character information contour correction apparatus and method of TV receiver

The present invention solves the deterioration of the resolution and the focus of the character information when the TV is used as a monitor such as a computer, in the contour correction for the character information, and the character information contour correction device of the TV receiver for displaying clearer character information. And to a method.

The configuration of the contour correction apparatus of the conventional TV receiver is shown in Figure 1,

A video input terminal (1) for inputting a video signal, a brightness and color separator (2) for separating the video signal input through the video input terminal (1) into a luminance signal (Y) and a color signal (C), and A contour correction section 3 for correcting the contour of the luminance signal separated by the luminance and color separation section 2 and applying the corrected luminance signal Y 'to the RGB interface section 4; and the contour correction section 3 RGB interface unit 4 for applying the corrected luminance signal of < RTI ID = 0.0 > and < / RTI > the color difference signal C separated by the luminance and chrominance separating unit 2 to the CRT 5 as an R / G / B signal, and the RGB interface unit ( It is composed of a CRT (5) for displaying the R / G / B output from 4) on the screen, and a microcomputer (6) for controlling each part.

Operation of the contour correction device of a conventional TV receiver configured as described above is shown in Figure 1,

First, an image signal input through the image input terminal 1 is separated into a luminance signal Y and a color signal C by the luminance and color signal separation unit 2.

At this time, when the separated luminance signal Y is applied to the contour correction unit 3, the contour correction unit 3 detects the contour of the image signal and enhances the detected contour portion to correct the luminance signal Y '. ) Is output to the RGB interface unit 4.

The RGB interface unit 4 receives the corrected luminance signal Y 'and the color signal C separated from the corrected luminance signal Y', and outputs the R / G / B signal to the CRT 5 to display the screen more clearly. do.

As shown in Table 1, the resolution of the character information is lower than that of the monitor, the focus of the TV receiver is worse than the focus of the monitor, and the TV compensates for the outline of the entire image.

Projection TV TV monitor resolution Small Medium and below Large focus Small Medium and below Large brightness Small Large Medium and below price Small Large Medium and below Oversized Large Medium or higher Small

However, when the conventional TV receiver, that is, a large TV or a projection TV, is used as a computer monitor, the resolution of the text information is poor, the focus is poor, and the text information cannot be displayed clearly, and the contour of the luminance signal is corrected. Since the contour correction unit 3 corrects the contours of not only characters but also the entire image, it is difficult to use for a monitor of a computer requiring a high resolution, and it is difficult to solve the problem that the focus of the TV receiver is lower than that of the monitor.

In order to solve the above problems, the present invention separates only a text signal from an image signal, compensates for the contour of the separated text information, and adjusts the head of the text signal to compensate for deterioration of focus, thereby obtaining clearer picture quality. In one embodiment, a character information area separator for separating the area of the character signal information and the general image signal among the image signals separated by the luminance and color separator, a character line width adjusting unit for adjusting the line width of the separated character information signal, The character information contour processing unit including the luminance signal reinforcing unit for enhancing the luminance of the character information is configured to display more clear character information.

1 is a block diagram of a contour correction apparatus of a conventional TV receiver

2 is a block diagram of the character information contour correction apparatus of the present invention TV receiver

3 is a block diagram showing an embodiment of the character information contour processing unit which is the main part of the present invention;

4 is a diagram showing a division between a horizontal character region and a general image region from a video signal according to the present invention;

5A is a view showing a horizontal character area detected by the present invention.

(B) shows the text area with vertical / horizontal line width adjusted

6 is a flow chart showing a method of correcting the character information contour of the TV receiver of the present invention.

7 is a flowchart illustrating a method of extracting a horizontal character region from an image luminance signal in the character information contour correction method of the TV receiver according to the present invention.

8 is a flowchart illustrating a method of extracting text information from a horizontal text area according to the present invention.

9 is a flowchart illustrating a method of adjusting a horizontal line width in a text area according to the present invention.

10 is a flowchart illustrating a method of adjusting a vertical / horizontal area of a character area according to the present invention.

The configuration of the character information contour compensator of the projection TV receiver of the present invention for achieving the above object is divided into a character signal information region and a general image information region in an image signal to adjust the line width of the divided character information region and to adjust the luminance signal. And means for enhancing the sharpness of the character information.

The configuration of the character information contour compensator of the projection TV receiver of the present invention is as shown in FIG.

A luminance and color separation unit 11 that receives an image signal and separates the color signal C and the luminance signal Y, and decodes the separated color signal C and outputs the color difference signals RY and BY. The chroma decoding unit 12 and the separated luminance signal Y and the color difference signal RY and BY compensate for the outline of the character information, and then use the (RY) ', (BY), and (Y)' signals as RGB signals. The character information contour processing unit 13 output to the interface unit 14, and the (RY) ', (BY)', (Y) 'signals are input to each CRT tube 15a, 15b, 15c, and R, G, And an RGB interface unit 14 for outputting the B signal, and a microcomputer 16 for controlling each unit.

3 is an embodiment of the character information contour processor 13;

A / D converter 131 for converting each input video signal (Y, RY, BY) into a digital signal, and image storage for storing each digital signal converted in the A / D converter 131 A character information area separator 133 for separating character information and an area of an image signal from the stored digital luminance signal Y, and character information and a general image in the character information area separator 133; A character line width adjusting unit 134 for adjusting the line width of the character information by receiving the luminance signal and the digital color difference signals RY and BY having the region separated therein, and the luminance of the character information output from the character line width adjusting unit 134. A luminance signal reinforcing unit 135 for reinforcing, a luminance signal Y 'for which character information is enhanced in the luminance signal reinforcing unit 135, and a color difference signal [(RY)', (BY) 'for adjusting the character line width; The D / A converter 136 receives a signal and converts the signal into an analog signal.

Here, the A / D converter 131 includes an A / D converter 131A for converting an input Y signal into a digital Y signal, an A / D converter 131B for converting an input RY signal into a digital RY signal, A / D converter 131C which converts input BY signal into digital BY signal,

The image storage unit 132 may include a storage unit 132A for storing the digital Y signal converted by the A / D converter 131A, and a storage unit for storing the digital RY signal converted in the A / D converter 131B ( 132B) and a storage unit 132C for storing the digital BY signal converted by the A / D converter 131C.

On the other hand, Figure 6 is a character information contour correction method of the present invention TV receiver,

A horizontal character area information extraction step of extracting a horizontal character area by detecting a line having a sum of brightness per horizontal line greater than a threshold; A character area division step of discriminating a character area by determining whether the sum of each column is zero with respect to the detected horizontal character line; A line width adjusting step of adjusting the line width by deleting the character information of the previous line when the luminance signal of the horizontal and vertical lines is zero for the divided character area; And a brightness signal reinforcing step of reinforcing the brightness signal with respect to the image signal whose line width is adjusted.

Then, the horizontal character area information extraction step is shown in Figure 7,

A first step of binarizing image information (0, 1) and then setting an initial value (i = 1, count = 0, h = 0); If the sum of the brightness [Ysum (i)] of each horizontal line i of the binarized image signal after the first step is compared with the threshold α, the horizontal character area is increased if the value is greater than the threshold α. A second step of dividing into a horizontal character information area (H); In the second step, if the sum [Ysum (i)] of the brightness per line of the image signal is less than or equal to the threshold value α, a comparison is made whether the count is an initial value. As a result, the count is an initial value (= 0). A third step of searching for the next horizontal line and determining if the count is within the set range (β &lt; γ) if it is not the initial value (= 0); When the counting result of the third step is within the setting range (β <count <γ), the horizontal character area h is detected and the horizontal line of the next horizontal character area is searched, and the count is within the setting range. If not (β <count <γ), proceed to the fourth step to search for the horizontal line of the next horizontal character area.

8 shows a process of extracting a text information region for implementing the text information contour correction apparatus of the present invention TV receiver.

Set the initial value (x = 0, count = 0, a = 0, h = 0) and add the sum [CYsum (x)] from the beginning to the end of the column of the horizontal character area of the certain (x) [CYsum (x)]. 0 "); As a result of the determination in the first process, if the sum of the rows for each column of the horizontal character area continues to be zero (= 0) within the range of the total number of columns col (x≥col), the count value is within the set range (ε <count). A sixth step of judging whether &lt; In the sixth step, when the count value is within the set range (ε <count <δ), the character area (a) is formed. Therefore, the horizontal character area (h) is changed to the next horizontal character area and the character area. A seventh step of comparing with the horizontal information area H and searching for the next horizontal text area and text area if the count is not within the setting range; If the horizontal character area h is greater than or equal to the horizontal character information area H, the result of the comparison in the seventh step is terminated. If the horizontal character information area H is smaller than the horizontal character information area H, the character information of the next horizontal character area is reduced. Eighth step of extracting the region; proceeds to.

9 is a method for implementing horizontal width adjustment of each character area.

When the luminance value Y (i, j) of the video signal is detected and the detected luminance value is zero ("0"), the horizontal line i is increased by one, and the horizontal line width is continuously compared with the total horizontal line M. A ninth step of reducing one line; If the luminance value detected in the ninth step is not zero, it is determined whether the count is an initial value (= 0). If the count is an initial value (= 0), the luminance value is zero. If the horizontal line is searched and the count is not the default, the tenth step of searching for the next horizontal line is performed.

The process for implementing the horizontal / vertical line width adjustment as shown in FIG. 10 by using the horizontal line width adjustment by FIG. 9 is as follows.

An eleventh step of adjusting a horizontal (i) line width (M) by receiving a value [Y (i, j)] for the luminance signal; When the horizontal line width is adjusted in the eleventh step, the twelfth step of adjusting the vertical line width N is performed.

The operation of the character information contour correction apparatus and method of the present invention TV receiver configured as described above will be described with reference to FIGS. 2 to 10.

First, as shown in FIG. 2, when an input image signal is separated into a luminance signal Y and a color signal C by the luminance and color separation unit 11, the separated color signal C is converted into a chroma decoding unit ( Decoded in 12) and applied as the color difference signals RY and BY to the character information contour processing section 13 together with the separated luminance signal Y.

The text information contour processing unit 13 receives the image signals R-Y, B-Y, and Y to process the contour of the text information.

FIG. 3 is a first embodiment of the character information contour processing unit 13, which will be described with reference to this. The Y, RY, and BY signals are included in the A / D converter 131A included in the A / D converter 131. As shown in FIG. 131B is inputted to 131C, converted into digital signals (1, 0), and applied to respective storage units 132A, 132B, and 132C included in the image storage unit 132.

At this time, the binarization of the video information, that is, the conversion of the digital signal is converted to "1" if the brightness of the luminance signal Y (x, y) in the video signal is greater than or equal to a specific value (general video information). Is converted to "0" and binarized. Since the text signal at this time is brighter than the general video signal, most of the text signals have a value of "1".

That is, [Y (x, y)] ≥specific value ⇒ [Y (x, y)] = 1, [Y (x, y)] <specific value ⇒ [Y (x, y)] = 0 do.

The image storage unit 132 storing the binarized (0, 1) image information is applied to the character information area separator 133 by applying the digital luminance signal Y stored in the storage unit 132A. The text information area separator 133 distinguishes between the text signal information and the area of the general image signal from the digital luminance signal Y.

The implementation method thereof will be described below with reference to FIG. 7.

First, in extracting horizontal text area information, after binarizing image information, initial values are set to horizontal line (i) = 1, count (CNT) = 0, and horizontal text area line (h) = 0.

When the initial value is set, the sum Ys (i) of the brightness of each line (i = i-th line) of the image luminance signal is obtained. That is, since the text signal has a horizontally continuous distribution, the text signal becomes larger than the sum of the brightness of the lines of the general video [threshold value].

At this time, the sum of the brightness per line [Ysum (i)] of the luminance signal is compared with the threshold [alpha] and continues for more than a few lines (vertical direction) and continues beyond the threshold [alpha] within the range of the entire horizontal line M. If it is bright (large), the horizontal character area is divided into horizontal character information area (h = H).

That is, the Ysum (i) value per line is within the range of the total horizontal line (M) for each horizontal line in which the count increases (CNT = CNT + 1) and the horizontal line increases (i = i + 1). If the light continues to be greater than the threshold α, the horizontal line is divided into the horizontal character information area H as shown in FIG. 4.

Here, the text (character) of the character information is the horizontal line between the line and the line, and the line with the character is distributed several lines in a row, so the sum of brightness [Ysum (i)] for each line is continuous for several lines or more. If larger than the threshold α, the horizontal character information area h is divided.

However, if the sum of the brightness of the luminance signal [Ysum (i)] is less than the threshold value α, then when the count is the initial value (= 0), the next (i + 1) of the next (i + 1) th line in the i-th line. The search starts from the horizontal line.

Then, when the sum [Ysum (i)] of the luminance signals is smaller than the threshold value α and the count is not the default value (= 0), that is, the image information area, the setting range of the count (β <CNT < γ) is determined, and if the count value is within the setting range, the start line [hs (h) = i-count-1] and the end line [he (h) = i-1] of the h-th horizontal character area are detected.

In order to detect the start line [hs (h)] and the end line [he (h)] of the h-th horizontal character area, and to search the h + 1-th horizontal character area, the count is set to an initial value (= 0) and then i-th. In the horizontal line, the horizontal character area for the i + 1th horizontal line is distinguished.

However, if the count value is out of the setting range (β <CNT <γ), the count is set to the initial value (= 0) to search for the h + 1th horizontal character area, and then the horizontal character area for the i + 1th line. Will be distinguished.

Here, the setting range β <CNT <γ of the count is included in the horizontal line width M.

For the horizontal character lines detected as described above, it is determined whether the sum of each column is zero to distinguish the character area a.

As shown in Fig. 8, the initial value (X = 0, count (CNT) = 0, a = 0, b = 0) is set, and the sum from the start row to the end row of the X-th column of the horizontal character area [CYsum ( X)] is compared to zero ("0"). This is a blank between lines, so their sum is zero ("0").

As a result of the comparison, the X-th column whose value [CYsum (X)] is "0" by counting and weighting the columns {CNT = CNT + 1, x = x + 1} is greater than the total number of columns col. In the same case, it is determined whether the count CNT is within the setting range ε <CNT <δ.

When the count CNT is within the set range (ε <CNT <δ), the character information in the horizontal character information [s (a); character area start value / e (a); character area end value] is the h-th horizontal. If the horizontal character area is greater than or equal to the horizontal character information area H, the character area is h + 1th and the ath character information area is a + 1th.

However, when the count value is not within the setting range (ε <CNT <δ), the h-th horizontal character area is set to h + 1th, the a-th character information area is set to a + 1th, and then the horizontal character area ( If h) is smaller than the horizontal character information area H, character information for the next horizontal character area is extracted.

Here, the setting range ε <CNT <δ of the count is included in the total number col.

Therefore, if the sum of all rows for the column in the horizontal character area is "0", the next column is the character area, and if the horizontal character area line (h) is greater than or equal to the horizontal character information (H), Only the character area as shown in FIG. 5A is extracted.

That is, it divides vertically among the horizontal character area lines and obtains the sum [CYsum (X) = "0"] from the start line to the end line of the column of the constant (X) horizontal character area. This is the text information, the horizontal line between the line and the line is the margin part, so if you get the sum from the start line to the end line for each column, there is a column whose value is "0".

Therefore, if the sum of all rows of each column is " 0 ", the next column is the character area, so only the character area is detected.

However, even if the image area is divided into horizontal character areas, there are only a few columns whose sum is "0" in the case of the image area.

Therefore, only the character information area containing the characters is extracted from the columns divided into the horizontal character information areas as described above.

On the other hand, when the character region and the normal image area is separated by the character region separator 133 as described above, the signal separated from the character region and the general image region is the color signal storage unit 132B of the image storage unit 132. The digital color signals RY and BY outputted at 132C are applied to the character line width adjusting unit 134.

As described above, the character line width adjusting unit 134 receives the luminance signal Y and the digital color signals RY and BY in which the character region and the general image region are separated to adjust the character line width in order to improve the focus. . This is because the resolution of the TV receiver is lower than the resolution of the computer monitor, so when the original data is displayed, the line is thick and the focus drops.

In order to solve this problem, the character line width adjusting unit 134 outputs a thinner line in the vertical / horizontal direction than the original data to accurately represent the character information.

9 is a flowchart showing a method of adjusting the horizontal line width of each character area.

First, the initial value (horizontal line (i) = 0, count = 0) is set, and then the comparison is made as to whether the image information luminance value [Y (i, j)] is zero ("0"). The luminance value of the point immediately preceding the line of the character in the line where the character is displayed is "0".

As a result of the comparison, when the image information luminance value [Y (i, j)] is zero (“0”), the horizontal line of the next (i = i + 1) is set with the count (CNT) as the initial value (= 0). If i) is less than or equal to the entire horizontal line M, the horizontal line width M is reduced by one.

That is, since the luminance value of the point immediately preceding the line of the character in the horizontal line (i) where the character is displayed is "0", the line having the value of "0" is obtained and the luminance of the immediately preceding point (i = i + 1). Set the value to "0" to thin the line.

However, if the video information luminance value [Y (i, j)] is not zero ("0"), it is determined whether the count is zero, and if the video information luminance value [Y (i, j)] is zero ("0"), the video information luminance value [Y (i, j)] is zero, so that the horizontal line width of the i = i + 1th horizontal line is adjusted by setting the count to "1".

However, if the count is not zero ("0"), the line width for the next horizontal line (i = i + 1) is adjusted.

On the other hand, by adjusting the vertical line width (N) in the same way as the horizontal line width control method is to output a thin line width of the entire character for one line. It is the same as FIG. 5 (b) of this figure.

10 is a method for adjusting the character line width (N, M) for the vertical / horizontal axis [Y (i, j)] of the character,

That is, after obtaining a value for the luminance signal Y (x, y), the horizontal width M is adjusted as shown in FIG. 8 described above, and when the horizontal line width is adjusted, the vertical axis is the same as the method thereof. (j) in the vertical line width (N) to adjust the vertical line width.

On the other hand, if the character line width is thinned by the character line width adjusting unit 134 and then outputs the corrected luminance signal Y 'and the color difference signal RY' (BY) ', the character line width is adjusted. The signal Y 'is enhanced by the brightness enhancing unit 135 to be brighter than the original brightness signal and output.

That is, by increasing the luminance (Y) 'value of the points where the binarized luminance value of the character information area is "1" than the original value, it is displayed clearly on the screen.

Therefore, the image signal is divided into a horizontal character information area and a general image information area, a text information area is extracted from the divided horizontal text information area, a horizontal line width is adjusted from the extracted text information area, and a vertical line width is then adjusted. After the vertical / horizontal line width of the character information is adjusted, the character signal is strengthened and output.

The luminance enhancing unit 135 receives a signal Y 'having enhanced luminance of text information and a color difference signal RY', (BY) 'outputted from the character line width adjusting unit 134. Reference numeral 136 converts the analog signal and outputs the result to the RGB interface unit 14.

The R / G / B interface unit 14 converts the (Y) ', (RY)' and (BY) 'signals, which are converted into analog signals, into R, G and B signals, respectively. Character information is displayed more clearly by outputting R, G, and B signals at 15c).

At this time, the microcomputer 16 controls the operation of each unit to correct the outline of the character information.

As described above, the present invention extracts the character information area from the image information in order to compensate for the degradation of the resolution and the deterioration of the character information generated when a large display device such as a large TV or a projection TV is used as a computer monitor. By adjusting the line width of the character information and then strengthening the outline of the character information, it is possible to give a confidence to the user by displaying a clear character even in an image including the character and the picture information such as hyper text.

Claims (6)

A luminance and color separation unit for separating the input image signal into a color signal and a luminance signal, a chroma decoding unit for decoding the separated color signal and outputting the color difference signal, and receiving the separated luminance signal and the color difference signal. A character information contour processing unit for compensating the contour of the information and outputting the compensated color difference signal and the luminance signal, an RGB interface unit for receiving the compensated luminance signal and the color difference signal and outputting the R, G, and B signals to each CRT; Character information contour correction device of a TV receiver, characterized in that composed of a microcomputer to control the respective parts. The display apparatus of claim 1, wherein the character information contour processor comprises: an A / D converter for converting each input video signal into a digital signal, and an image storage unit for storing the video signal digitally converted by the A / D converter. And a character information area separator that separates character information and image signal regions from the luminance signal of the stored video signal, and a luminance signal and a digital color difference from which the character information separated from the character information area separator and the general image region are separated. Character information is enhanced by a character line width adjusting unit for receiving a signal and adjusting the line width of the character information, a luminance signal reinforcing unit for enhancing the luminance of the character information output from the character line width adjusting unit, and the luminance signal reinforcing unit. And a D / A converter which receives the luminance signal and the color difference signal having the corrected character line width, and converts them into analog signals. Character information contour correction apparatus of the receiver. A horizontal character area information extraction step of extracting a horizontal character area by detecting a line having a sum of brightness per horizontal line greater than a threshold; A character area division step of discriminating a character area by determining whether the sum of each column is zero with respect to the detected horizontal character line; A horizontal width adjusting step of adjusting horizontal width by deleting character information of a previous line when the luminance signal of horizontal and vertical lines is zero for the divided character area; And a luminance signal reinforcing step of reinforcing the luminance signal with respect to the image signal whose line width is adjusted. 4. The method of claim 3, wherein the extracting the horizontal text area information comprises: a first step of binarizing image information and setting an initial value; A second step of comparing the sum of brightness of each horizontal line of the binarized video signal in the first step with a threshold value and dividing it into a horizontal character area when the result is lighter than a threshold value by more than a predetermined line; In the second step, if the sum of the brightness per line of the video signal is less than or equal to the threshold value, the count value is compared with the initial value. If the result is the initial value, the next horizontal line is searched. A third step of determining whether is within a setting range; If the counting result of the third step is within the setting range, the horizontal line for the next horizontal character area is searched after detecting the start and end lines of the horizontal character area, and the count value is not within the setting range. And a fourth step of searching for a horizontal line for a next horizontal character area. 4. The method of claim 3, wherein the character area classification step comprises: a fifth step of setting an initial value and determining whether the sum of the start line to the end line is zero for each column of the horizontal character area; A sixth step of judging whether the count value is within a setting range when the total row total for each column of the horizontal character area continues to be zero within the number range of all columns; In the sixth step, if the count value is within the setting range, the start value and end value of the character area are detected, and then the next horizontal character area and the character area are set. A seventh step comprising a horizontal character area and a character area; An eighth step of terminating if the horizontal character area is greater than or equal to the horizontal character information area as a result of the comparison in the seventh step; and extracting the horizontal character information area for the next horizontal character area if the horizontal character area is smaller than the horizontal character information area; Character information contour correction method of the TV receiver, characterized in that the progress. The ninth aspect adjusting method of claim 3, wherein the adjusting the horizontal line width comprises: detecting the luminance value of the image signal and increasing the horizontal line by one when the detected luminance value is zero, thereby decreasing the horizontal line width by one line. Steps; If the luminance value detected in the ninth step is not zero, it is determined whether the count is an initial value. As a result, if the count is an initial value, it is determined that the luminance value is zero. Otherwise, the tenth step of searching for the next horizontal line; character information contour correction method of the TV receiver, characterized in that proceeds.