JP2930125B2 - Image forming device with shadow - Google Patents

Description

The present invention relates to an image forming apparatus for decorating a document image by adding another image to the document image, and is used, for example, in a copying machine or a facsimile machine. .

(B) Conventional technology Conventionally, in this type of image forming apparatus, an image in which a part of a document image is surrounded by a frame line or an image in which a mesh pattern is superimposed on a part of a document image are formed. It has been known.

(C) Problems to be Solved by the Invention However, there is a demand for further diversification of image decoration in such an image forming apparatus.

The present invention has been made in view of such circumstances, and provides an image forming apparatus capable of obtaining an image decorated on a document image.

(D) Means for Solving the Problems The present invention relates to a photoelectric conversion unit that horizontally and vertically scans a document image and converts it into an electric signal for each pixel, and an A / D that performs A / D conversion of an output of the photoelectric conversion unit. Conversion means, signal conversion means for converting the output of the A / D conversion means into a binary serial signal representing white pixels and black pixels, and again after the signal output from the signal conversion means changes from black to a white pixel signal. A detecting means for detecting a shadowable area until a change from white to a black pixel signal; and a combination of a predetermined number of serial white and black pixel signals serving as a reference, the number of which is changed and a combined shadow signal is alternately formed. Shadow signal forming means for output, setting means for setting a shadow area to be added after the signal output from the signal conversion means changes from black to white pixel signal, and horizontal scanning for each signal output by the signal conversion means. For each line, The shadowed image forming apparatus includes an adding unit that adds the shadow signal to a smaller one of a set shadow region and a reproducing unit that reproduces a binary serial signal to which the shadow signal is added into an image.

As the photoelectric conversion unit, a CCD image sensor, a MOS image sensor, or the like is used. Further, a laser printer, a thermal transfer printer, an ink ribbon printer, or the like is used as the reproducing means.

FIG. 1 is a block diagram showing the configuration of the present invention.
Reference numeral 1 denotes a photoelectric conversion unit that horizontally and vertically scans an original image and converts it into an electric signal for each pixel, 102 denotes an A / D conversion unit that performs A / D conversion of an output of the photoelectric conversion unit 101, and 103 denotes an A / D conversion unit. A signal conversion means for converting the output of 102 into a binary serial signal representing a white pixel and a black pixel, 104 is a signal from the signal conversion means 103 which changes from black to a white pixel signal and then again from white to a black pixel signal Detecting means for detecting a shadowable area until the change, 105 outputs a shadow signal in which the number is changed and alternately combined from a predetermined number of serial white pixel signals and black pixel signals as a reference. A shadow signal forming means 106 is a setting means for setting a shadow area to be added after the signal output from the signal converting means 103 is changed from black to a white pixel signal, and 107 is a horizontal signal for the signal output from the signal converting means 103. Between the shadowable area and the set shadow area for each scan line An addition unit 108 adds a shadow signal to any of the smaller areas, and a reproduction unit 108 reproduces a signal output from the signal conversion unit and to which the shadow signal is added, as an image.

(E) Operation In FIG. 1, when the photoelectric conversion means 101 horizontally and vertically scans the original image and converts it into an electric signal for each pixel,
D conversion means 102 A / D converts the electric signal. The signal converter 103 converts the digital output of the A / D converter 102 into a binary serial signal represented by white pixels and black pixels. The detection means 104 detects a shadowable area from when the binary serial signal changes from black to a white pixel signal to when it changes again from white to a black pixel signal. The setting means 106 is a signal conversion means 1
Set the shadow area to be added after the signal output from 03 is converted from black to white pixel signal. Further, the signal forming means 105 outputs a predetermined number of serial white pixel signals and black pixel signals serving as a reference, which are changed in number and alternately combined as shadow signals. Then, with respect to the signal output from the signal conversion unit 103, the shadow signal is added to the narrower one of the shadowable area and the set shadow area for each horizontal scanning line.
The image data is reproduced by the image reproducing means 108, which is a binary serial signal added by 7 and to which a shadow signal is added. In this way, the original image is converted into a binary image signal of white and black, and after the black image signal, a stripe-shaped shadow image signal is added, and then reproduced. Therefore, the stripe-shaped shadowing process on the image is performed in real time.

(F) Embodiment Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. This does not limit the present invention.

FIG. 2 is a structural explanatory view showing an embodiment in which the present invention is applied to a copying machine, wherein 1 is a document, 2 is a mounting table on which the document 1 is placed, 3 is a document cover, and 4 is moved in the direction of the arrow. The lamps 5, 6 and 7 are mirrors for reflecting image light from the original 1, the mirror 5 moves together with the lamp 4 in the direction of the arrow, and the mirrors 6 and 7 control the speed of the lamp 4. It also moves in the direction of the arrow at half the speed. The image light of the document reflected by the mirror 7 passes through the f · θ lens 8
The light is received by a CCD type image sense (hereinafter referred to as CCD) 9. CCD9 arranges 1000 to 5000 photosensors in a chip form, accumulates the electric charges photoelectrically converted by the sensors in a built-in capacitor, transfers the charges of all the photosensors to a built-in shift register by a trigger signal, and outputs them sequentially. It has become. Next, the image of the original 1 received by the CCD 9 is converted into a video signal by a signal processing circuit described later. Reference numeral 10 denotes a semiconductor laser that turns on / off laser light in response to the video signal, 11 denotes a polygon mirror that reflects laser light emitted from the semiconductor laser, 12 denotes a motor that drives the polygon mirror, and 13 denotes a polygon mirror. The mirror irradiates the laser beam onto the photosensitive drum 14 rotating in the direction of the arrow. The photoconductor drum 14 has a main charger in advance.
When the laser beam is received, the electrostatic latent image is formed, and the developing device 15 forms a toner image. When the transfer paper 17 is supplied from the transfer paper cassette 16, the toner image is transferred to the transfer charger.
Transferred to transfer paper by 18. The transfer paper onto which the toner image has been transferred is separated from the photosensitive drum 14 by a separation charger 19, conveyed to a fixing device 21 by a conveyor belt 20, fixed by the fixing device 21, and carried out to a tray 23. The laser light emitted from the semiconductor laser 10 is horizontally scanned by a polygon mirror and vertically scanned by rotation of the photosensitive drum 14 in the direction of the arrow, so that an electrostatic latent image corresponding to the image of the original 1 is Formed on

FIG. 3 is a block diagram showing an image processing circuit of the embodiment shown in FIG. 2, and an image signal detected by the CCD 9 is
The signal is converted into an 8-bit digital signal by the A / D converter 24. Then, the shading correction circuit 25 and the logarithmic correction circuit 26 correct variations in the light amount distribution of the lamp 4 for illuminating the original and variations in the sensitivity of the photo sensor of the CCD 9.
Further, the image signal is input to the shadowing processing circuit 27 and the dither processing circuit 28. In the shadow processing circuit 27, the image data is subjected to shadow processing, and in the dither processing circuit 28, the image data is binarized by a threshold value that changes for each pixel, that is, a dither matrix. Next, the data selector 29 outputs the output of the shadow processing circuit 27 to the semiconductor laser 10 of the image reproduction circuit 10a in the area specified by the area generation circuit 30, and outputs the dither processing circuit in the other areas. Is output to the semiconductor laser 10 of the image reproducing circuit 10a. In this manner, the image of the original 1 is subjected to the shadowing process on the necessary portions and is copied onto the transfer paper 17.

Hereinafter, the shadowing processing circuit 27 will be described in detail.

4 to 6 are electric circuit diagrams for explaining details of the shadowing processing circuit 27. FIG. First, in the circuit C1 of FIG. 4, a digital image signal S1 and a preset binary threshold signal
S2 is compared by the comparator 31, and a binary image signal S3 is output as "1" if the image signal S1 is larger than the threshold value and "0" if it is less than the threshold value. This signal S3
And the basic clock signal S4 and the horizontal synchronization signal S5a are input to the D flip-flop 32. And a digital image signal
S1 is converted into a binary serial signal S3 representing a white pixel and a black pixel, and a shadowable area is processed from when the signal S3 changes from black to a white pixel signal until it changes again from white to a black pixel signal. It is output as an enable signal S0.

The circuit C2 in FIG. 5 is a circuit for generating a shadow width effective area signal, 33 is a counter, 34 is a comparator, 35 is an OR gate,
36 is a D flip-flop, and 37 is an AND gate.

By inputting the processing enable signal S0 and the shadow width setting signal S5 to the circuit C2 shown in FIG. 5, a signal representing the smaller one of the two, that is, the shadow width effective area signal S6
Is output.

FIG. 6 shows a circuit for generating a shadow signal and adding it to the image signal, 38 and 39 are counters, 40 is an UP / DOWN counter, and 41 and 42.
Is a comparator, 43 to 45 are D flip-flops, 46 and 47
Is an AND gate, 48 and 49 are OR gates, and 50 is an inverter.

The operation in such a configuration will be described with reference to a time chart shown in FIG.

When the processing enable signal S0 becomes High, the clear state of the counter 38 is released, and the counter 38 becomes valid. Since the binary image signal S3 is input in synchronization with the clock signal S4, one count of the counter 38 has one pixel width. The comparator 41 outputs a signal S8 which becomes High when the output S7 of the count 38 matches the stripe white width setting signal 15. If the output of the comparator 41 is High, the D flip-flop 43 outputs a signal S9 that goes high in synchronization with the clock signal S4, and the output signal S9 that goes high continues until a clear signal is input. . Output S9 of D flip-flop 43
Becomes high, the clear state of the counter 39 is released,
The counter 39 becomes valid. Comparator 42 is a counter
When the output S11 of 39 and the output 10 of the UP / DOWN counter 40 match, a signal S12 which becomes High is output. At this time, the UP / DOWN counter 40 outputs an initial value (one pixel in this case) set by the setting signal S16. Output S12 of comparator 42
Is high, the D flip-flop 44 outputs the clock signal
Low is output in synchronization with S4, and Hig is output at the next output clock.
Returns to h. When the output S13 of the D flip-flop 44 becomes Low, the counter 38 and the D flip-flop 43 are cleared, the output S7 of the counter 38 becomes 0, and the output S9 of the D flip-flop 43 becomes Low. Output S9 of D flip-flop 43 is L
When it becomes ow, the counter 39 is cleared (output
S11 = 0). Also, the output S of the D flip-flop 43
The falling edge of 9 is input as a clear signal to the clock input (CK) of the UP / DOWN counter 40, and the output S10 of the UP / DOWN counter 40 counts up.

The output S13 of the D flip-flop 44 goes low only during one cycle of the clock signal S4. When the output S13 of the D flip-flop 44 returns to the high state, the counter 38 and the D flip-flop 44 43 becomes effective.

While the processing enable signal S0 is High, the above operations are repeated. The D flip-flop 45 receives the output S9 of the D flip-flop 43 as an input signal, and generates a stripe shadow in synchronization with the clock signal S4 while the shadow width effective area signal S6 is High. S14
Is output. Then, the logical sum of the signal S14 and the binary image signal S3 is obtained by the OR gate 49, and the result is output as the shaded image signal S18. Thereby, a shaded image as shown in FIGS. 8 and 9 is formed. That is, in these figures, (a) is the original image portion, and (b) is the shadow portion. FIG. 8 shows a case where the UP / DOWN setting signal S17 is set to UP, and FIG. 9 shows a case where the signal S17 is set to DOWN. In these figures, N is the signal S1
The stripe white width set by 5 and Mo are the stripe black width initial values set by the signal 16. further,
FIG. 10 is an image diagram showing an example of a shadowed image actually formed by this embodiment.

FIG. 11 is a diagram corresponding to FIG. 6 showing a modification of the above embodiment. The circuit shown in FIG. 11 is a circuit obtained by removing the UP / DOWN counter 40 from the circuit of FIG. 6 and adding an OR gate 48a, and the other configuration is the same as that of the above-described embodiment. Therefore, in the circuit of FIG.
And the stripe white width setting signal S15,
A shadowed image as shown in FIG. 12 is formed.

That is, in FIG. 12, (a) shows the original image portion,
(B) is a shadow portion, where N is the stripe white width set by the signal S15, and M is the stripe black width set by the signal S19. FIG. 13 is an image diagram showing an example of a shadowed image actually formed by this modification.

(G) Effects of the Invention According to the present invention, it is possible to add a stripe-shaped shadow of an arbitrary width to a document image in real time when reproducing the document.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the present invention, FIG. 2 is an explanatory diagram of the configuration of one embodiment of the present invention, FIG. 3 is a block diagram showing a control circuit of the embodiment shown in FIG. 2, and FIG. ~ 6th
3 is a circuit diagram showing the main part of FIG. 3, FIG. 7 is a time chart showing the operation of the electric circuit diagram shown in FIG. 6, and FIGS. 8 and 9 are schematic diagrams showing the relationship between the original image and the shadow. Explanatory diagram shown in
FIG. 10 is an image diagram showing an example of a shadowed image actually formed by the embodiment shown in FIG. 2, FIG. 11 is a diagram corresponding to FIG. 6 showing a modification of the present invention, and FIG. FIG. 13 is an explanatory diagram schematically showing the relationship between a document image and a shadow according to FIG. 13, and FIG. 13 is a diagram corresponding to FIG. 10 according to a modification. 31,34,41,42 ... Comparator, 32,36,43-45 ... D flip-flop, 33,38,39 ... Counter, 37,46,47 ... AND gate, 35,48,49 ... OR gate, 40 …… UP / DOWN counter, 50 …… Inverter.

Claims (2)

(57) [Claims] 1. A photoelectric conversion means for horizontally and vertically scanning a document image and converting it into an electric signal for each pixel, an A / D conversion means for A / D converting an output of the photoelectric conversion means, and an A / D conversion means. And a signal conversion means for converting the output of the signal into a binary serial signal representing a white pixel and a black pixel, and from when the signal output from the signal conversion means changes from black to a white pixel signal and then again from white to a black pixel signal Detecting means for detecting a shadowable area of, and a shadow signal forming means for outputting a shadow signal combined alternately by changing the number from a predetermined number of serial white pixel signals and black pixel signals as a reference, Setting means for setting a shadow area to be added after the signal output from the signal conversion means changes from black to a white pixel signal; and a shadowable area for each horizontal scanning line for the signal output by the signal conversion means. Or the smaller of the set shadow areas Adding means for adding the shadow signal to the area, shaded image forming apparatus comprising a reproducing means for reproducing a binary serial signal shadow signal is added to the image. 2. A photoelectric conversion means for horizontally and vertically scanning a document image and converting it into an electric signal for each pixel, an A / D conversion means for A / D converting an output of the photoelectric conversion means, and an A / D conversion means. And a signal conversion means for converting the output of the signal into a binary serial signal representing a white pixel and a black pixel, and from when the signal output from the signal conversion means changes from black to a white pixel signal and then again from white to a black pixel signal Detection means for detecting a shadowable area, shadow signal formation means for outputting a shadow signal obtained by combining a predetermined number of black pixel signals after a predetermined number of serial white pixel signals, and a signal output from the signal conversion means. Setting means for setting a shadow area to be added after changing from black to a white pixel signal, and a signal output by the signal conversion means, for each horizontal scanning line,
An image forming apparatus comprising: an adding unit for adding the shadow signal to a smaller one of the shadowable region and the set shadow region; and a reproducing unit for reproducing a binary serial signal to which the shadow signal is added into an image. apparatus.