JPH011366A - Electronic whiteboard device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronic blackboard device that optically reads images such as characters and figures written on a blackboard.

2. Prior Art Conventionally, this type of device includes a blackboard as a writable material;
It comprises a light source and an optical reading device using a line-shaped photoelectric conversion element, reads an image written on a blackboard by moving these relatively, and reproduces the image based on the electrical signal obtained by this reading, This was recorded on a recording medium to electronically copy the image written on the blackboard.

Problems to be Solved by the Invention However, conventional devices of this type have difficulty in determining the state (range) of an image such as a character or figure written on a blackboard.

Because the entire surface of the blackboard was scanned at a constant speed regardless of the density (density), it always took a certain amount of time for K to complete the copy, regardless of the state in which the image was written. .

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an electronic blackboard device that can change the sub-scanning speed depending on the written state of the image on the blackboard, thereby shortening the copying time. Means for Solving the Problem In order to achieve the above object, the present invention detects written or unwritten parts on the blackboard, and the control means controls the relative movement speed of the scanner and the blackboard and the recording according to the detection result. This configuration is configured to variably control the speed in the sub-scanning direction.

Effect of the Invention With the above-described configuration, the present invention can shorten the time for reading and recording blank areas on the blackboard, and in turn, shorten the time for copying images.

Embodiment FIG. 1 is a block diagram showing an electronic whiteboard device according to an embodiment of the present invention.

In Fig. 1, 11 takes in a pixel clock B, a line synchronization signal C, and a binary image signal obtained by a scanner reading the blackboard for each predetermined line, and based on these data, determines the presence or absence of an image written on the blackboard. A written line detection circuit (hereinafter referred to as a detection circuit) for making a determination; 12 a line panzer memory (hereinafter referred to as a memory) for capturing and storing a binary image signal; 13 a detection circuit 11. Memory 12. This control unit is connected to the drive means of the scanner and the recording paper conveyance means of the copying machine, and changes the signal content based on the determination result of the detection circuit 11 to control each connected circuit.

As shown in FIG. 2, the detection circuit 11 includes a NOR circuit 14 inputting the binary image signal and the line synchronization signal
It is provided with first stage and second stage JK flimp floats 15 and 16 connected to the R circuit 14.

Input terminal j of the first stage 7-lip flop 15 NOR
It is connected to the circuit 14, and its input terminal is grounded. Further, the clear terminal FK receives the line synchronization signal C as a negative logic via the inverter 17, and the clock terminal T
The pixel clock B output for each pixel is taken in.

Input terminals J and K of the second stage flip-flop 16 are both connected to an output terminal Q of the first stage clip-flop 15. Also, a line synchronization signal C is taken into the clock terminal T, and a written line detection signal E is sent out from the output terminal Q.

When the control unit 13 receives the writing line detection signal E at the rH9 level, it reads the data from the memory 12 and sends it out as recording data, and also sends a recording paper feed control signal to the recording paper conveyance means to convey the recording paper. and moves the scanner to the next line at a predetermined speed in response to a scanner control signal. Further, when the writing line detection signal of "L level" is taken in, the data is not read from the memory 2 and the scanner is moved to the next line at high speed in response to the scanner control signal.

The operation of the electronic whiteboard device configured as above will be described below.

First, a scanner reads the blackboard screen and binarizes it to obtain a binary image signal. This binary image signal is taken into the memory 12 and the detection circuit 1.

When the read signal enters the valid period and the line synchronization signal C becomes LOW, the pixel clock B begins to be taken into the first stage JK flip-flop 15.

Then, when the line synchronization signal C is LOW, when the scanner reads the writing on the blackboard and the binary image signal becomes LOW as shown in FIG. 3, the NOR circuit 14 sends the 'H' signal to the first stage. The JK flip 70 is output to the input terminal J of the flip 5. At this stage, when the rising edge of the pixel clock B is received, the first stage flip-flop 15 sets the output signal of the output terminal Q to the lHl level, and the input signal of the input terminal J changes to the lHl level.
During the level, that is, while the line synchronization signal C is LOW, the output signal of the output terminal Q is reported to the (Hl level) and outputted to the second stage flip-flop 16.

When the level of the input signal at the input terminals J and K of the second stage flip 70 knob 16 is 'H level, when the line synchronization signal C reaches the 'H level after entering the line invalid section, the second stage flip 70 knob 16 16 outputs the written line detection signal E to the control unit 13 at H level.

The control unit 13 detects the written line detection signal E of the H level.
By taking in the data, the scanner is controlled by the scanner control signal and moved to the next line position at a predetermined speed, while data is read from the memory 12. Furthermore, the control unit 13 sends out a recording paper feed control signal to control the recording paper transport means to convey the recording paper, and also sends out the data read from the memory 12 as recording data and uses it for recording on the recording paper.

In addition, when the line synchronization signal C is at the l L l level and there is no written part on the blackboard for one line, and the binary image signal continues to be at the (H+l level), the NOR circuit 14
The output of the first stage JK flip 70 tube 15 continues to maintain the Ll level, and the output of the first stage JK flip 70 knob 15 also becomes the lL7 level. In this case, the second stage JK flip-flop 16 outputs the line description line detection signal E at the "L" level even if the line synchronization signal C reaches the "H" level.

The control unit 13 receives the written line detection signal at the j L l level and moves the scanner to the next line position at high speed in response to the scanner control signal. Note that at this time, the control unit 13 does not read data from the memory 12, and the recording paper is transported in synchronization with the movement of the scanner, and no recording is performed.

In this way, the speed of reading and recording in the sub-scanning direction is changed depending on the situation of the written part 2 and the unwritten part on the blackboard, thereby shortening the time required for copying.

According to this embodiment, when there is no written part on the blackboard, data is not read from the memory 12.
Sending out recording data is also omitted, further reducing the time required for recording.

Further, in this embodiment, the detection circuit shown in FIG. 2 is used, but the present invention is not limited to this, and the configuration of the logic circuit may be changed.

Further, in this embodiment, a case where a written portion on a blackboard is detected is taken as an example, but an unwritten portion or both may be detected.

As described in detail, the present invention detects when there is no written part on any line on the blackboard, and increases the scanner movement speed and recording paper feeding speed, thereby shortening the copying time. be able to.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an electronic whiteboard device according to an embodiment of the present invention, Fig. 2 is a circuit diagram showing a detection circuit of the electronic whiteboard device, and Fig. 3 is a timing chart showing an example of the operation of the electronic whiteboard device. 0 11... Written line detection circuit, 12... Line buffer memory, 13... Control unit 0 Name of agent Patent attorney Toshio Nakao and 1 other person 2nd
Figure 3 Figure 5

Claims (1)

[Claims] An electronic blackboard device comprising means for detecting at least either a written portion or a non-written portion on a blackboard, and means for controlling a sub-scanning speed of reading and recording based on the detection result of the detecting means.