JPH01237594A - Signal processing circuit - Google Patents

Abstract

PURPOSE:To prevent an omission of a character and to surely execute the transmission of information by converting a picture drawing screen of a dot unit to a picture drawing screen of a block unit. CONSTITUTION:Whether a block position which has been brought to block division to (m)X(n) dot units is overlapped with a position in which a character has been brought to picture drawing or not is detected by a block detecting circuit 1 and a character position detecting circuit 2. As a result, when they are overlapped, from only a part corresponding to a character position in those which have been brought to block division to (m)X(n) dots, a MAX color and a NEXT color are detected by a MAX detecting circuit 3 and a NEXT color detecting circuit 4. As a result, the dot corresponding to the MAX color in the character position is left as it is by a block color converting circuit 5, and other dots and the dots which have been block division of the outside of the character position are all brought to conversion picture drawing in the NEXT color. In such a way, picture drawing of the character can be executed surely.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to the field of converting and coloring a dot-by-dot drawing screen drawn on a screen into block units, specifically, in the field of color drawing in videotex. The present invention relates to a signal processing circuit used when converting and drawing a colored drawing screen using the NAPLPS method of the North American method to the CAPTAIN method of block coloring drawing of the Japanese method.

Prior Art In conventional block coloring conversion drawing, the screen is simply divided into blocks of m x n dots, and the most common color and the next most common color are detected from among the multiple colors used in that block. As a result, the inside of the block is converted and drawn using the detected color.

Problems to be Solved by the Invention However, in this conversion method, it is difficult to accurately convert and draw the characters that need to be considered most important as information, and the problem is that it becomes impossible to decipher the text in the converted drawing result. was there.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to reliably reproduce character drawing using division conversion drawing in block units.

Means for Solving the Problems In order to achieve this object, the present invention provides a block detection circuit that divides a screen into blocks of m×n dots, and a block detecting circuit that divides a screen into blocks of m×n dots and a block detection circuit that divides the screen into blocks of m×n dots. m from the character position detection circuit that detects the overlap with the character drawing position, and the detection signals detected by the character position detection circuit and the block detection circuit.
× Maximum number of character drawing colors in a block in units of n dots (M
) color and the next most common (NEXT) color, respectively.
X color detection circuit and NEXT color detection circuit, and these M
A signal processing circuit is used that includes an AX color detection circuit and a block color conversion circuit that converts and draws the drawing color in an m×n divided block based on the signal detected by the NEXT color detection circuit.

According to the above means, the block detection circuit and the character position detection circuit detect whether the block position divided into blocks of m×n dots overlaps the position where a character is drawn. Detection result: m×n if there are duplicates
MAX color and NEXT color iMA from only the part corresponding to the character position in the block divided into dots! Detection circuit N
Detected by ICX T color detection circuit. As a result of the detection, the block color conversion circuit leaves the dots corresponding to the MAX color within the character position as they are, and converts all other dots and block-divided dots outside the character position to NEXT.
Conversion drawing will now be performed using color, and character drawing will now be performed reliably.

Example FIG. 1 shows a block diagram of one embodiment of the invention.

In the figure, 1 is a block detection circuit, which divides the image signal a into units of x n dots and outputs the divided image signals as a character position detection circuit 2.
, 1iAX color detection circuit 3 and NEXT color detection circuit 4
supply to.

2 is a character position detection circuit, which detects whether the image signal a overlaps with the block position of the divided image signal S, and is a circuit that detects whether the image signal a overlaps with the block position of the divided image signal S.
It is supplied to the color detection circuit 3 and the NEXT color detection circuit 4.

3 is a MAX color detection circuit, which detects the most frequently used MAY color from the overlapping portion of the divided image signal when the overlap presence/absence signal C indicates detection, and converts the converted MAX color signal d into a block color. It is supplied to the conversion circuit 6.

4 is a NEXT color detection circuit, and if the overlap presence/absence signal 0 indicates detection, it detects the next most used NEXT color from the overlap part in the divided image signal and blocks the converted NEXT color signal e. It is supplied to the color conversion circuit 6.

Reference numeral 6 denotes a block color conversion circuit which converts and draws the drawing color in the divided block indicated by the divided image signal depending on the presence or absence of the converted MAX signal d and the converted NICXτ signal e.

Next, specific operations will be explained with reference to FIGS. 1 to 6.

When an image signal a as shown in FIG. 2 is input to the block detection circuit 1, the block detection circuit 1 outputs nXl1,
nX! II+1-...-n+2Xm, n+2Xm+1
The head is divided into... First, let us consider the case of division into m×n as shown in FIG. The m×n divided image signal is supplied to a character position detection circuit 2.

The character position detection circuit 2, supplied with the divided image signal, checks whether the character position detection circuit 2 overlaps with the character drawing position (indicated by xxY in the figure) managed by itself.

The background color of the characters in the m×n blocks in Figure 2.

It is clear from this figure that the divided image signal and the character drawing position overlap, including the back color of the character color 9M of L. Because of the overlap, the character position detection circuit 2 flags the overlap presence/absence signal and sends the overlap presence/absence signal C to the vAx color detection circuit 3 and the NEXT color detection circuit 4 together with the management address.

The MAX color detection circuit 3 that receives the overlap presence/absence signal C,
The color used most often in the character position is detected (in FIG. 2, the character background color of K is detected as the color most often used). When the MAW color is detected, the converted vAx color signal d is supplied to the block color conversion circuit 6.

The NEXT color detection circuit 4 detects the second most common color used in the character position (in Figure 2, the character color L is detected as the second most common color)1. Detects the NEXT color. Then, the converted NEXT color signal e is sent to the block color conversion circuit 6.
supply to.

The block color conversion circuit 6 that receives the converted MAX color signal d and the converted N and KXT color signals e leaves the color indicated by the converted MAX color signal d as is in the divided image signal,
All remaining dots are converted and drawn using the color indicated by the conversion NEXT color signal O. This state is shown in FIG. 3a. As is clear from the figure, the inside of the block is rendered and converted using the WAX color and NEXT color indicated at the character position.

The above operations are performed as shown in nXl1 in FIG. nXm+1・
...n+2Xm, n+2Xl! By performing drawing conversion sequentially as I+2, each converted drawing block as shown in FIG. 3 is completed. Figure 4 shows each block assembled on a screen. FIG. 5 shows the drawing results obtained by the conventional technique. As is clear from Fig. 4, the font colors can also be accurately expressed. Therefore, according to the present invention, it is possible to prevent the omission of characters that have the most meaning as information.

Effects of the Invention As described above, in the present invention, by converting a dot-by-dot drawing screen into a block-by-block drawing screen, missing characters can be prevented and information can be transmitted reliably.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing the block division state, FIG. 3 a to 1 is a diagram showing the results of drawing the converted blocks, and FIG. 4 is the conversion result FIG. 6 is a diagram showing the conversion result of the conventional example. 1...Block detection circuit, 2...Character position detection circuit, 3...MAX color detection circuit, 4.
...NEXT color detection circuit, 5...Block color conversion circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 4 Figure 5

Claims (1)

[Claims] a block detection circuit that divides a screen into blocks of m×n dots; a character position detection circuit that detects overlap between the divided m×n dot blocks and character drawing positions on the screen; A MAX color detection circuit and a NEXT color detection circuit that respectively detect the most common character drawing color and the next most common color in a block of m×n dots from respective detection signals detected by the detection circuit and the block detection circuit. m by the signals detected by these MAX color detection circuit and NEXT color detection circuit.
A signal processing circuit comprising a block color conversion circuit that converts and draws drawing colors in ×n divided blocks.