JPH04191986A - Character synthesizer - Google Patents

Abstract

PURPOSE:To surely perform character synthesis by setting a threshold value for binarization variably, and extracting the character of a character original as character data even when the back ground of the character is not white and clear difference exists in density or tint to some extent. CONSTITUTION:The character original is read by a reading means 103 which outputs digital multivalue data, and the threshold value used for binarization in the generation of binarized character data of a synthetic character by a binarization means 105 is set variably, not as a fixed value, and plural points that become the reference of density in the character original are read in advance to decide the threshold value before the character original is read. The binarization of the character original is performed after the threshold value is calculated based on read data. Thereby, it is possible to surely extract a prescribed character in the character original.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a character synthesis device that reads a character manuscript, generates binary character image data, and synthesizes it with other multivalued image data.

[Prior Art] Conventionally, when attempting to synthesize text into an image using a reading device that outputs digital multi-valued data, the image reading device first reads the text document and then binarizes it using a predetermined threshold. Generate binary image data of composite characters using a circuit and store it in memory (Next, there is a method of reading the image in which you want to composite characters, combining it with the character data stored in memory, and outputting it. It had been taken.

[Problem to be solved by the invention]

However, in the conventional example, the threshold value used when converting the read digital multivalued character data into binary data is a predetermined fixed value, so depending on the text document, it may be difficult to appropriately extract the characters to be synthesized. Can not.

For example, suppose there is a manuscript containing characters as shown in FIG. FIG. 6 shows the density level of one line 1-1' in this document. Here, the background of the character "a" and the character "s" are halftone, and the density level of this area is on the darker side than a predetermined threshold value. Therefore, when the original shown in FIG. 5 is subjected to character synthesis, the half-tone background including the character a and the character S is also extracted, and there is a drawback that only the character a and the character S cannot be extracted.

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned points, an object of the present invention is to provide a character compositing device that can reliably combine characters and images regardless of the density of a character document.

[Means to solve the problem]

The present invention includes: a reading unit that reads a character manuscript or an image manuscript and outputs digital multivalued character data or image data; a threshold determining unit that reads density reference points in the text manuscript and calculates a binarization threshold; Binarization means for inputting digital multi-value character data output from the reading means and outputting binary character data based on the binarization threshold; and digital multi-value output from the reading means. image data and a compositing means for composing the binarized character data.

[For production]

According to the present invention, when a character manuscript is read by the reading means for outputting digital multi-valued data and the binarized character data of a composite character is generated by the binarization means, the threshold value used for disulfuration is not fixed. In order to determine this threshold value, before reading the text document, read multiple points that serve as density standards in the text document in advance, calculate the threshold value based on the read data, and then read the text document twice. By converting it into a value, it is possible to reliably extract a predetermined character from a character manuscript.

〔Example〕

Examples of the present invention will be described in detail below.

FIG. 1 is a block diagram showing a first embodiment of the present invention applied to a color document reading device. In FIG. 1, 101 is a character original of characters to be combined, 102 is an image original of an image to be combined with characters, 103 is a color original reading device that reads the original, and 104 calculates a threshold value used when converting character data into binary data.・A storage circuit, 105 is a circuit that binarizes character data, 106 is a memory that stores the binarized character data, 107 is a synthesis circuit that synthesizes image data and character data, and 108 is a calculation circuit. equipment, 109
is the operation section.

Next, the operation of this embodiment will be explained. First, the color document reading device 103 reads one character in the character document 101, and reads C (cyan) and 1M (magenta).

Each density component of Y (yellow) and K (black) is stored in the threshold calculation circuit 104. Each of these values is SC1
+SMl+SYI, SKI.

Next, one point on the background in the character manuscript 101 is read and these values are set as S C21S M□ and Sy□+SK2, respectively.

Next, the threshold value calculation circuit 104 compares the character density and background density for each color, and among the colors in which the character density is darker, the color with the largest difference between the character density and the background density is used to binarize the character data. Use this as the standard color. The threshold value S at that time is calculated as shown in (Formula 1).

s= (S, +S,)/2 ... (1) Example Eva,
Character density is distorted t'Lsc, =DOH,S,, =DO
H.

SY + =30)1. SX l =808, background density is 5e2 = 00H, respectively.

Syt”50) 1.Syi:50H,Sxz”20H is set.

max(Sr −St) is Cyan and the threshold is 5c
=65H.

Next, an area of characters to be synthesized in the character original 101 is read by the color original reading device 103 and sent to the character data binarization circuit 105. When converting text data into binarization, the density information of each pixel of the text data (CMYK) other than the color determined as the reference color for binarization is ignored, and the threshold value is used for the reference color for binarization. and convert it into a binary value. Therefore, each pixel becomes monochromatic binary data. The binarized data is stored in memory 106. Next, when the color of the character to be synthesized is inputted from the operation unit 109, data on the color of this character is sent to the character synthesis circuit 107 via the arithmetic unit 108.

Finally, specify the reading area and character composition area of the image original 102, and use the color original reading device 103 to read the image original 102.
Read 02. This image data and the character binary data stored in the memory 106 are sent to the character synthesis circuit 107, and the character binary data is converted into binary CMYK data for each pixel so that the specified color is obtained. When converted and combined, pixels whose binary character data bits are on will output the on color as FFH, and the off color as OOH, and for other pixels, , outputs multi-valued image data through. The flow of the above operation is shown in the flowchart of FIG.

As a result, binary character data is generated using the color with the largest density difference between the characters and the background, so even a character original with a halftone background can be used as an original for character data.

The embodiment shown in FIG. 2 has the same structure as the first embodiment. In this embodiment, when character data is binarized, the color tone of each pixel is used as a reference.

First, one character in the character manuscript 101 is read.

Each of these concentration data is S. , SM, SY, S
Let's call it K.

At this time, the threshold value for binarizing character data is set in the range of ±IOH of S for each color, and only pixels that satisfy the conditions for all four colors are determined to be characters, and binary data of characters is generated. However, since the upper limit of the concentration is FFH and the lower limit is OOH, the upper limit of the threshold value S8. The lower limit is as follows.

5cL=liaX(Se-10H,0OH), 5cH
=llin(Sc+10H,FFH)Sb+L”maX
(Sb+-10H,0OH), SM, 2m1n (S,
+lOH,FFH)Syt=llaX(Sy IOH
,0OH), Syo=min(Sc+10H,FFH
)SKL”1OaX (Sx-10H,0OH), Sx
H=min(Sx+10H, FFH) The other data flow is the same as in the first embodiment. The flow of this embodiment is shown in the flowchart of FIG.

As a result, only characters of a predetermined color in a text document can be converted into binary data.

The configuration of the embodiment shown in FIG. 3 is also the same as that of the first embodiment. In this embodiment, the binary character data is stored in the memory and displayed on the panel. If the user wants to change the threshold after looking at this display result, he or she operates the operation unit to change the reading threshold for text originals. The threshold value can be changed any number of times.

After determining the threshold value, the process is the same as in the first embodiment. FIG. 4 shows the processing procedure of this embodiment.

As a result, the threshold value can be finely adjusted and the character data can be confirmed on the panel, so that desired characters can be extracted and character composited.

〔Effect of the invention〕

As described above, according to the present invention, even if the background of characters in a character document is not white, if there is a certain degree of clear difference in density or color, the characters can be extracted as character data. This enables reliable character synthesis.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing one embodiment of the present invention, Fig. 2 is a flowchart of the first embodiment, and Fig. 3 is a flowchart of the second embodiment.
FIG. 4 is a flowchart of the third embodiment, FIG. 5 is an explanatory diagram of a text manuscript, and FIG. 6 is a flowchart of the text manuscript shown in FIG. FIG. 3 is a diagram showing concentration distribution. 101... Text original, 102... Image original, 103... Color original reading device, 104... Character synthesis threshold calculation/storage circuit, 105.
...Binarization circuit for character data, 106...Memory, 107...Character synthesis circuit, 108...Arithmetic unit, 109...Operation unit.

Claims (1)

[Scope of Claims] 1) A reading means for reading a character original or an image original and outputting digital multivalued character data or image data, and a threshold value for reading a density reference point in the character original and calculating a binarization threshold. a determining means; a binarizing means for inputting the digital multi-valued character data output from the reading means and outputting binary character data based on the binarization threshold; 1. A character synthesizing device comprising: a synthesizing means for synthesizing the digital multivalued image data and the binarized character data.