JPH0618438B2 - Image processing device - Google Patents

Description

The present invention relates to an image processing apparatus for electrically processing an image.

Generally, in a video amplifier circuit of an image reading apparatus using a solid-state image sensor such as a CCD, an automatic level control (hereinafter referred to as ALC) circuit and an automatic gain control are provided in order to cope with a change in the DC output level or the AC output level of the CCD. A circuit (hereinafter referred to as AGC) is used. When the original image is read and the image is printed on the recording medium at the same time, the CCD and the ALC circuit are driven at a predetermined timing by inputting a synchronization signal from the printer.

Therefore, since the synchronization signal is not input from the printer while the printer is stopped, for example, the image signal is temporarily stored in the image memory from the CCD, and then the image signal is supplied from the image memory to the printer for recording. It was not possible to print the image on the body.

The present invention has been made in view of the above points, and not only directly supplies an image signal obtained by reading an original image to perform an image printing operation, but also temporarily stores the image signal obtained by reading the original image. However, the purpose is to supply the stored image signal to perform the image printing operation.
A reading unit that photoelectrically reads the original image, an image memory that stores the image signal output from the reading unit, and a recording based on the image signal output from the reading unit or the image signal read from the image memory Printing means for printing an image on the body, input means for inputting an external synchronization signal from the printing means, forming means for forming a pseudo synchronization signal by counting a predetermined clock signal, and external synchronization from the input means. In the case of printing an image by directly supplying the image signal output from the reading unit to the printing unit and printing the image signal, the driving unit driving the reading unit and the image memory according to a signal and a pseudo-synchronization signal from the forming unit. , The driving means drives the reading means in accordance with an external synchronizing signal from the input means, The image signal output from the reading means is supplied to the printing means in synchronization with an external synchronizing signal, while the image signal output from the reading means is temporarily stored in the image memory and stored in the image memory. When an image signal is supplied to the printing means to print an image, the driving means drives the reading means and the image memory in accordance with a pseudo-synchronization signal from the forming means to output the image output from the reading means. A signal is stored in the image memory in synchronization with a pseudo synchronization signal, and the image memory is driven in accordance with the external synchronization signal from the input means to synchronize the image signal read from the image memory with the external synchronization signal. And an image processing device for supplying the image to the printing means.

If the synchronizing signal from the printer is interrupted by noise, vibration, etc., the ALC circuit will not be able to sample the level, and the ALC circuit will malfunction to cause level disturbance. Further, even if the sync signal is restored, the disturbance of the level is not immediately restored due to the time constant of the ALC circuit and the ACG circuit.
Therefore, even if the synchronization signal from the printer is interrupted at a low frequency, the influence on the image is extremely large.

The present invention has been made in view of the above points, and a reading unit that photoelectrically reads an image, an image memory that stores an image signal from the reading unit, and an external synchronization that inputs an external synchronization signal from an external device. A signal input means, an internal synchronization signal output signal for outputting an internal synchronization signal, and writing of the image signal from the reading means into the image memory based on the internal synchronization signal are controlled, and based on the external synchronization signal. An image processing apparatus having a control means for controlling reading of an image signal from the image memory is provided.

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of the image control device, and FIG. 2 is its timing chart. 1 is a CCD, 2 is a video amplifier circuit for amplifying the analog signal read by the CCD 1, and 3 is A for keeping a black level in the video signal constant.
An LC circuit, 4 is a transfer clock generator for driving the CCD 1, and 5 is a counter for counting the transfer clock, and outputs an ALC control signal and a pseudo sync signal by counting a predetermined number of pulses. 6 is an OR gate, 7 is a reset pulse generator, and 1 is input by the input from the OR gate 6.
A reset signal is output for each line.

The operation will be described below with reference to the timing chart of FIG. The image signal read by the CCD 1 is transferred by the clock φ _T (11) output from the transfer clock generator 4, is input to the video amplifier 2, is amplified, and is then AL.
It is output to the C circuit 3. The counter 5 counts this transfer clock φ _T , and the ALC control signal φ _A (12) is set to A in synchronization with the output timing of the cell that always outputs the black level because the light receiving cell of the CCD is optically masked.
Output to the LC circuit 3. As a result, the ALC circuit 3 performs the level sampling of the black level and performs control so as to keep the black level constant. Therefore, the ALC circuit 3 outputs the video signal 13 whose black level is kept constant.

The transfer clock is also input to the reset signal generator 7, and the synchronizing signal H _SYNC (8) from the printer is sent to the OR gate 6
When it is input to the reset signal generator 7 via the reset signal generator 7, a reset signal φ _SYNC synchronized with the transfer clock φ _T is output to the CCD 1 and the counter 5. This causes the CCD 1 to output a video signal.

Here, for example, in FIG. 2, when the (N + 1) th and subsequent synchronization signals H _SYNC are not output from the printer due to noise, vibration, etc., the (N + 1) th reset signal φ _SYNC is not output from the reset signal generator 7. , The counter 5 is not reset. Therefore, when the synchronizing signal H _SYNC is input from the printer, the Nth pseudo H _SYNC (10) which is reset and is not actually output is output from the counter 5 at a predetermined timing, and is output via the OR gate 6. Input to the reset signal generator 7. In the present embodiment, the Nth pseudo H _SYNC is slightly delayed from the timing at which the (N + 1) th synchronization signal φ _SYNC is output.
Is output. As a result, FIG.
The reset signal is output to the CCD1 and the counter 5, and the CCD1 performs reset and image signal transfer again.
The ALC circuit can also perform level sampling.

FIG. 3 is a block diagram of an image reading control device according to the present invention using an image memory.

In the figure, the same components as those in FIG. 1 have the same components,
Reference numeral 15 is an A / D converter for binarizing the video signal 13, 16
Is an image memory for storing a binarized video signal, 17
Synchronization signal H _SYNC at the printer constituted by a laser or the like
Is applied to the OR gate 6. Reference numeral 18 is an address counter for writing the image information read by the CCD 1 into the image memory 16, and 19 is an address counter for reading the image information from the image memory 16, which uses a common address bus. Reference numeral 20 is a clock pulse generator for driving the address counter 19, 21 and 22, 27 are inverters,
Reference numerals 23 and 24 denote NAND gates, which form an RS flip-flop together with the inverters 21 and 22. Reference numeral 25 is a resistor, and 26 is a light emitting diode, which is lit and displayed when the synchronizing signal H _SYNC from the printer 17 is input to the reset signal generator 7.

When, for example, the write mode is selected by the read / write (R / W) signal 29, the address counter 18 is set to "H".
A level signal is applied and the bus is enabled. At this time, the "L" level signal is applied to the address counter 19 by the inverter 27, and the address counter 19 becomes high impedance. When the read mode is selected, the address counter 18 has a high impedance and the address counter 19
Becomes the bus enable. In the write mode, the address counter 18 has a clock φ _T for driving the CCD 1.
The image information read by the CCD 1 is address-controlled by the address counter 18 and sequentially stored in the image memory 16. In the read mode, the clock pulse generator 20 inputs the clock to the clock and the printer 7 inputs the simultaneous signal H _SYNC to the address counter 19, and the image information stored in the image memory 16 is address-controlled by the address counter 19. It is sequentially output to 17, and an image is written on the recording medium by a laser or the like.

Start signal 28 by turning on a copy key (not shown)
Becomes "H" level, the address counters 18, 19
Is initially reset. The image information read by the CCD 1 is output to the printer 17 via the video amplifier circuit 2, the ALC circuit 3, and the A / D converter 15, and the address is controlled by the address counter 18 to control the image memory 1.
6 is stored. Even if the sync signal from the printer 17 is not output for some reason, the pseudo H
_{Since SYNC} is output from the reset pulse generator 7 to the CCD 1 and the counter 5, the original image can be continuously read by the CCD 1 and the information can be stored in the image memory 16.

Further, in this apparatus, since the image information can be temporarily stored in the image memory 16, it is possible to stop the printer 17 and read the image by using the pseudo H _SYNC as the synchronizing signal.

As described above, according to the present invention, by driving the reading means in accordance with the external synchronizing signal, the image signal output from the reading means is supplied to the printing means in synchronization with the external synchronizing signal. The output image signal can be directly supplied to the printing means to print an image, and by driving the reading means and the image memory in accordance with the pseudo synchronizing signal, the image signal output from the reading means is changed to the pseudo synchronizing signal. Output from the reading means by supplying the image signal read from the image memory to the printing means in synchronization with the external synchronization signal by storing the image signal in the image memory in synchronization with The stored image signal is temporarily stored in the image memory, and the stored image signal is supplied to the printing means. It is possible to image printing.

[Brief description of drawings]

FIG. 1 is a block diagram of the image reading control device, FIG. 2 is a timing chart thereof, and FIG. 3 is a block diagram of the image reading control device when an image memory is provided. 1 is a CCD, 2 is a video amplifier circuit, 3 is an ALC circuit, 4
Is a transfer clock generator, 5 is a counter, 7 is a reset pulse generator, 15 is an AD converter, 16 is an image memory,
17 is a printer, 18 and 19 are address counters, 20
Is a clock pulse generator.

Claims (1)

[Claims] 1. A reading unit for photoelectrically reading an original image,
An image memory for storing the image signal output from the previous term reading means; a printing means for printing an image on a recording medium based on the image signal output from the previous term reading means or the image signal read from the image memory; Input means for inputting an external synchronizing signal from the printing means, forming means for forming a pseudo synchronizing signal by counting a predetermined clock signal, and an external synchronizing signal from the input means and a pseudo synchronizing signal from the forming means When the image signal output from the reading unit is directly supplied to the printing unit to print an image, the driving unit includes the reading unit and the driving unit that drives the image memory. An image signal output from the reading means by driving the reading means according to an external synchronizing signal. The image signal output from the reading unit is temporarily stored in the image memory, and the image signal stored in the image memory is supplied to the printing unit in synchronization with an external synchronization signal. When the image is printed by the driving means, the driving means drives the reading means and the image memory in accordance with the pseudo synchronization signal from the forming means to synchronize the image signal output from the reading means with the pseudo synchronization signal. By storing the image signal in the image memory and driving the image memory according to the external synchronizing signal from the input unit, the image signal read from the image memory is supplied to the printing unit in synchronization with the external synchronizing signal. A characteristic image processing device.