JP2892652B2 - Image processing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus such as a digital copying machine, and more particularly to a background removal and background output device.

(Prior art)

2. Description of the Related Art In image processing apparatuses, background removal such as removal of a background by deleting a minimum value has been performed. However, in this background removal method, if there is a variation such as the background being slightly stained, the background is weak and the background is simply deleted. In addition, the colors are printed on the characters and the like or the colors are changed due to the background output.

〔Purpose〕

The present invention solves the above-mentioned drawbacks of the prior art, and sets the gradation width (ground, etc.) of a single color or a plurality of colors and a specific color, and replaces the gradation width with the set specific color. It is an object of the present invention to eliminate the influence of a part such as a color character other than the background when outputting a specific color.

〔Constitution〕

In order to achieve the above object, the present invention provides an image processing apparatus that performs predetermined processing on an input image signal and outputs the processed image signal.
A background extraction unit that extracts a specific gradation or a background region having a specific gradation from the input image signal; and a color setting unit that sets a predetermined color, wherein the color setting is performed on the background region extracted by the background extraction unit. It is configured to output an image signal representing the color set by the unit.

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram schematically showing an image processing apparatus according to the present invention, in which 11 is a color setting input device, 12 is a specific gradation extracting device, and 13 is a region extracted by the specific gradation extracting device with a set color. This is the select device to be processed.

FIG. 2 is a block diagram showing details of the apparatus. This image processing apparatus outputs a set color when a specific gradation width (base) exists within an address range. In this case, R,
When the upper 6 bits of the luminance signal of 8 bits each for G and B (256 gradations) are all "1" (H level), if the address signal is within the address range, the set color signals R, G and B are output as 8 bits each. I do.

In this figure, reference numeral 21 denotes a color setting unit, which sets a color to be output as a base color by setting R, G, B 8 bits each. FIG. 3 shows the 8-bit memory 21a. The 8-bit memory 21a has three R, G, and B settings. Although shown in FIG. 3 by hardware, it may be set by software. Reference numeral 22 denotes a background extraction unit, which extracts a range of 252 to 255 of the luminance signal from the scanner as a background portion. Further, the background portion is "1" (H
Level) and the others are output as “0” (L level). 4th
The figure is a circuit showing a specific example. In this figure, G1 ~
G4 is the gate. Reference numeral 23 denotes an address signal setting unit which sets the address signal to "1" (H level) when the address signal is within the address range.
The output outside the address range is output as "0" (L level). FIG. 5 is a diagram showing the designated area.
X ₁ , Y ₁ , and the lower right point are X ₂ , Y ₂ . Figure 6 is a diagram showing an example of the specific circuit, the input coordinate specified by FIG. 5 only between and Y ₁ between the X ₁ of X ₂ of Y _2, address signals "1" ( H level). Flip flop
63 and 64 to maintain a constant period output, for X-axis, the X ₁ enters is fixed to "1", CLK much as the X ₂ is cleared when counted. 61 and 62 are counters. Reference numeral 24 denotes a select section, in which the address signal is “1” and the base portion is “1”
The set color signal is output only at the time of, and the other outputs the original color signal. FIG. 7 is a block diagram showing a specific example of this. In FIG. 7, the background portion in the address range is input as "1" by the AND gate G1. Is output.

The timing chart is shown in FIG. A base portion is extracted one pixel at a time by a CLK (clock) signal, and an AND with an address is taken to obtain an output signal. As described above, the circuit shown in FIG. 6 is used as the address signal generating means. By setting the above device, the range of the address signal ("1") and the background color (R, G, B all 252 to 25)
At 5), output a specific color.

9 and 10 are diagrams for explaining image processing according to the present invention, wherein (a) shows a document and (b) shows a copy sheet of the image processing result. In FIG. 9, the portion outside the background (character portion) in the designated address range is output as it is, and only the background portion is color-converted and output. In FIG. 10, the color of the background portion is changed over the entire area of the document surface.

〔effect〕

As described above, according to the present invention, a configuration is provided in which a background region having a specific gradation or a specific gradation width is extracted from an input image signal, and an image signal representing a predetermined color is extracted from the extracted background region. Thus, an effect is obtained in which the background such as a character document is removed, and a portion such as a color character other than the background is not affected.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing an image processing apparatus according to the present invention, FIG. 2 is a block diagram showing details of the image processing apparatus, FIG. 3 is a view showing an example of a color setting unit, and FIG. FIG. 5 is a circuit diagram showing an example of a unit, FIG. 5 and FIG. 6 are diagrams relating to an address signal setting unit, FIG.
6 is an example circuit diagram, FIG. 7 is a circuit diagram showing an example of the selection section, FIG. 8 is its timing chart, FIGS. 9 (a) and (b) and FIGS. 10 (a) and (b) () Is a diagram showing before and after image processing, respectively. 21: color setting section, 22: background extraction section, 24: selection section.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) H04N 1/38-1/393 H04N 1/40-1/409 H04N 1/46-1/62 G06T 1 / 00

Claims (1)

(57) [Claims] An image processing apparatus for performing predetermined processing on an input image signal and outputting the processed image signal, comprising: a base extraction unit for extracting a specific gradation or a base region having a specific gradation from the input image signal; An image processing apparatus, comprising: a color setting unit configured to output an image signal representing a color set by the color setting unit with respect to a base region extracted by the base extraction unit.