JP3402296B2 - Image drawing method and device for personal computer education support system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal computer education support system, and more particularly to a personal computer of each student subsystem in which each subsystem having a personal computer for teachers and a plurality of students is connected by the same cable. The present invention relates to an image drawing method for a personal computer education support system in which an analog image signal is transmitted to a teacher subsystem and an improvement of the apparatus.

[0002]

2. Description of the Related Art A personal computer (hereinafter abbreviated as personal computer) education support system uses a personal computer used by a teacher and a plurality of students as a local area network (L).
It is used for the purpose of supporting education in classrooms etc.

As an example of such an education support system, the "image display method and device of a personal computer education support system" described in Japanese Patent Laid-Open No. 8-278744 is known.

As shown in FIG. 6, the personal computer education support system described in this publication includes a plurality of n student subsystems 2a-2n, a teacher subsystem 20, and a teacher subsystem 20.
It is composed of a cable 11 connected between the two. Further, each of the student subsystems 2a-2n has a personal computer 4, a CRT 5, an operational amplifier 6 for transmitting an analog image signal, a distributor 7, a student screen controller 9, and a transmission switching relay 8, respectively, and a teacher subsystem. Reference numeral 20 denotes an operation panel 209, a control unit 208, an operational amplifier 201, a monitor CRT 211, a resolution determination unit 203, an A / D converter 202, a write timing generation unit 204, a video memory (hereinafter abbreviated as VRAM) 205a-205d, D.
-A converter 206, read timing generator 20
7 and a selection unit 210.

In this personal computer education support system,
From the operation panel 209 of the teacher subsystem 20, a personal computer image displayed on the CRT 5 of each student subsystem 2a-2n is displayed on the monitor CRT of the teacher subsystem 20.
When the execution of the “auto scan and multi-window display” to be transmitted to the 211 is instructed, the control unit 208 of the teacher subsystem 20 causes each of the student subsystems 2a-2n.
The student screen controller 9 is controlled to sequentially turn on the transmission switching relay 8. An analog image signal, which is a personal computer image of each student subsystem 2a-2n, is transferred to the cable 11 via the operational amplifier 6, the distributor 7, and the transmission switching relay 8.
When it reaches the teacher subsystem 20, the signal is amplified by the operational amplifier 201. The transmitted analog type image signal is converted into a digital type image signal by the A / D converter 202, and the resolution determination unit 203 determines the resolution from the synchronization signal of the personal computer image.
Based on the resolution determination result, the synchronization signal, and the signal from the control unit 208, the write timing generation unit 204 causes the VRA
The write control signal of M205a-205d is generated, and the image of the first student subsystem 2a is VRAM205a.
The images of the second, third, and fourth student subsystems are sequentially written to the VRAM 205b and the VRAM 205.
c, written in the VRAM 205d. Each VRAM 20
The digital image signals written in 5a-205d are
The read timing generation unit 207 reads out each student subsystem at a predetermined timing, converts it to an analog image signal by the DA converter 206, and sequentially arranges the converted analog image signal at a predetermined position. Then, the analog image in the multi-window display is displayed on the monitor CRT 211 through the selection unit 210.

By thus determining the resolution of the student subsystems and converting the images, even if the computer subsystems of the student subsystems 2a-2n have different resolutions, the student subsystems 2a-2n are The image of the personal computer can be displayed on the monitor CRT 211 of the teacher subsystem 20 in a multi-window display.

[0007]

In the above personal computer education support system, when a plurality of students are operating their own personal computers, the monitor CRT of the teacher subsystem is used.
Since the screen of the personal computer of the student subsystem can be monitored by, the teacher can give guidance to the student when an operation mistake is found. However, when giving instruction, even if you use the above-mentioned computer education support system, such as verbally, distributing explanation sheets to students, or moving the teacher to the place of the student's computer and giving direct instruction, I could not say that I could provide guidance smoothly and efficiently.

An object of the present invention is to use a coordinate input device such as a mouse from a teacher subsystem to mark an arrow or the like on the screen of a student's personal computer or to add an underline or the like. This is to provide a personal computer education support system that enables teachers to teach students more easily and efficiently. Even if the personal computers have different resolutions, the resolution is appropriate. The purpose is to provide a personal computer education support system that enables the display and use of pointer images of various sizes.

[0009]

According to the image drawing method of the personal computer education support system of the present invention, each subsystem having a personal computer for a teacher and a personal computer for a plurality of students is connected by the same cable. In an image drawing method of a personal computer education support system in which an image signal of a student subsystem is displayed on a teacher subsystem, an analog method of each student subsystem received and input by the teacher subsystem Image signal or an analog image signal input from a video device such as a teaching material presentation device of the teacher subsystem is converted into a digital image signal, and each image is converted by a synchronizing signal of the input analog image signal. The resolution is determined, and the resolution is generated according to the determined resolution. The digital image signal is stored in the first video memory by an imming signal, and an image of a pointer whose position is indicated by a coordinate input device such as a mouse and a trajectory image of the pointer are generated according to the determined resolution. Stored in the second video memory and the third video memory according to the generated timing signal, and
In the second video memory and the third video memory,
Each may be scaled down according to the resolution determined above.
Is an enlarged image of the pointer and the trajectory of the pointer
Storing the image, of the first video the memory image signals stored digitally in the second pointer stored in the video memory image and / or said third pointer stored in the video memory The locus image and the locus image are selected and read at predetermined timings and converted into an analog image signal, whereby the input analog image signal is combined with the pointer image and the pointer locus image to form a combined image. CRT of the student subsystem by generating and transmitting the composite image to the student subsystem.
It is characterized by being displayed on.

In the image drawing apparatus of the personal computer education support system of the present invention, each subsystem having a teacher personal computer and a plurality of student personal computers is connected by the same cable, and an image of each student subsystem is displayed. In a personal computer education support system in which a signal is displayed on a teacher subsystem, a first operational amplifier for receiving an analog image signal from the student subsystem and the first operational amplifier or the second operational amplifier are provided. A- which converts an analog image signal into a digital image signal
D converter, a plurality of first video memories for storing digital image signals corresponding to each of a plurality of divided multi-window screens, and an analog system from the first operational amplifier or the second operational amplifier Resolution determining section for determining the resolution of the image signal, and a plurality of the plurality of the resolutions determined by the resolution determined by the resolution determining section and the analog image signal synchronization signal from the first operational amplifier or the second operational amplifier. A first video memory, a second video memory, and a write timing generation unit that controls write timings to the third video memory; and a plurality of the first video memory, the second video memory, and the third video. D for converting a digital image signal written in the memory into an analog image signal
An A converter, a read timing generator that controls the read timing from the plurality of first video memories, the second video memory, and the third video memory, and an execution instruction such as "student screen reception" An operation panel for accepting, a control unit for controlling execution instructions from the operation panel, an output of the first operational amplifier or the second operational amplifier and the D-
It has a selection unit for selecting and outputting any image signal from the output of the A converter, and a monitor CRT for displaying the image signal from the selection unit, and further outputs a video image signal as a teaching material presentation device. A video device, a scan converter for converting a video image signal from the video device into an analog image signal, and the second operational amplifier for transmitting an image signal output from the scan converter,
An input selection relay for switching between the analog image signal from the second operational amplifier and the analog image signal of the student subsystem from the first operational amplifier, input of coordinates, and "marking image display ON, OF".
A coordinate input device with an operation switch including a mouse for giving an execution instruction such as “F”, a pointer data generation unit for generating the shape of the pointer input from the coordinate input device with the operation switch via the control unit, and a pointer A locus data generation unit that generates a locus image, the second video memory and the third video memory that store the pointer image data generated by the pointer data generation unit and the locus image data generated by the locus data generation unit, respectively. and video memory, and a third operational amplifier for transmitting an image signal in which the selecting unit selects the sub-system for students possess, the first
In the second video memory and the third video memory,
The reduction is performed according to the resolution determined by the resolution determination unit.
Reduced or enlarged pointer image data and
A teacher subsystem is characterized in that trajectory image data is stored .

Further, the read timing generator is a finger
Generate a timing signal of a specified specific resolution, and
As a timing signal of the specific resolution, a plurality of students
The timing of one resolution in the subsystem is specified
It is characterized by being done.

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a personal computer education support system of the present invention, FIG. 2 is an example of a screen display of a student subsystem and a teacher subsystem, and FIG. 3 is a diagram showing the embodiment of FIG. Operation timing chart, FIG. 4 is FIG.
4 is an operation timing chart of the DA converter of the embodiment.

In the present embodiment shown in FIG. 1, a plurality of n student subsystems 1a-1n and a teacher subsystem 3 are provided.
0 and a cable 10 connecting these subsystems to each other.

Each of the student subsystems 1a-1n has a personal computer 4, a CRT 5, an operational amplifier 6 for transmitting an analog image signal of the personal computer 4, and a distributor for distributing the output signal of the operational amplifier 6 to the teacher subsystem 30 and the CRT 5, respectively. 7, a transmission switching relay 8 that connects the output signal of the distributor 7 to the teacher subsystem 30, and switches between the received signal of the CRT 5 as the output signal of the distributor 7 or the output signal from the teacher subsystem 30. Reception switching relay 400,
The student screen controller 9 controls switching of the transmission switching relay 8 and the reception switching relay 400 by a control signal from the teacher subsystem 30.

The teacher subsystem 30 converts the analog image signal from the operational amplifier 201, the operational amplifier 201 or the operational amplifier 308 which receives the analog image signal from the student subsystem 1a-1n into a digital image signal. A-D converter 202,
Four VRAMs 20 for storing digital image signals corresponding to each of the four divided multi-window screens
5a-205d, a resolution determination unit 203 that determines the resolution of an analog image signal, VRAMs 205a-205d and VRAM3 depending on the determined resolution and the synchronization signal.
04a-write timing generation unit 204 for controlling write timing to VRAM 304b, VRAM 205
a-205d and VRAM 304a-VRAM 304b
DA converter 206, VR for converting the digital type image signal written in to the analog type image signal
AM 205a-205d and VRAM 304a-VRA
A read timing generation unit 207 that controls the read timing from the M304b, an operation panel 209 that receives an execution instruction such as “student screen reception”, and an operation panel 209.
Control unit 208 for controlling the execution instruction from the control unit 208
A control unit 210 for selecting and outputting an image signal of either the output of the operational amplifier 201 or the operational amplifier 308 or the output of the DA converter 206, and the monitor CRT 21 for displaying the image signal from the selecting unit 210.
1, a video device 300 that outputs a video image signal as a teaching material presentation device, a scan converter 301 that converts a video image signal from the video device 300 into an analog image signal, and an image signal that the scan converter 301 outputs Operational amplifier 308 for transmission, analog image signal from operational amplifier 308, and operational amplifier 20
1. Input selection relay 305 for switching between the analog image signals of student subsystems 1a-1n from 1; coordinates with operation switches including a mouse for inputting coordinates and performing execution instructions such as "ON / OFF of display of marking image" The input device 306, the pointer data generation unit 302 that generates the shape of the pointer input from the coordinate input device 306 with operation switches via the control unit 208, the trajectory data generation unit 303 that generates the trajectory image of the pointer, and the pointer data generation unit. The pointer image data generated by 302 and the locus image data generated by the locus data generation unit 303 are stored in the VRAM 304a and VRAM 304b, and the image signal selected by the selection unit 210 is set to the student subsystem 1
It has an operational amplifier 307 for transmitting to a-1n.

Next, the operation of this embodiment will be described.

First, an instruction to execute "receive student screen" is input from the operation panel 209 of the teacher subsystem 30.
Then, from the control unit 208, the student subsystem 1a-1
A control signal is sent to each student screen control unit 9 of n, each transmission switching relay 8 is sequentially turned on at a predetermined time interval such as an interval of 1 second, and the personal computer 4 passing through the operational amplifier 6 and the distributor 7 An analog image signal is sent to the cable 10 for each student subsystem. The personal computer images distributed by the distributor 7 are output to the CRT 5 of each student subsystem.

In the teacher subsystem 30, the cable 1
From 0 to the analog image signal of the personal computer image for each student subsystem 1a-1n sequentially input through the operational amplifier 201, and the video device 300 converted into the analog image signal through the operational amplifier 308 and the scan converter 301. Image signal of the operation panel 209
The input image is selected at, and the control unit 208 controls the input selection relay 305 so that the selected image signal is input.

The selected and input analog image signal is converted into a digital image signal by the A / D converter 202, and the resolution determination unit 203 determines the resolution from the synchronizing signal of the image signal. Based on the resolution of the determination result, the synchronization signal, and the signal from the control unit 208, the write timing generation unit 204 causes the VRAM 205.
The personal computer image of each student subsystem or the image of the video device 300, which is generated by generating the write signal to the a-205d, is sequentially written as digital image data in the VRAMs 205a-205d. When the personal computer image of each student subsystem is input, the image of the first student subsystem 1a is written to the VRAM 205a, then the image of the second student subsystem 1b is written to the VRAM 205b, and then the VRAM 205b. Third student subsystem 1
The image of c is written in the VRAM 205c, and then the image of the fourth student subsystem 1d is written in the VRAM 205d. After being written to the fourth VRAM 205d,
The next image of the student subsystem 1e is the VRAM 20.
It returns to 5a and is written. When the image of the video device 300 is input, the first image of the video device 300 is written to the VRAM 205a, the next image of the video device 300 is written to the VRAM 205b, the next image of the video device 300 is written to the VRAM 205c, and so on. Sequential VRAM 20
5d and then back to VRAM 205a for writing.

Next, when the pointer position data is input by operating the coordinate input device 306 with an operation switch of the teacher subsystem 30, the input pointer position data is subjected to coordinate conversion by the control unit 208.

Based on the pointer position data after coordinate conversion and the resolution determination result by the resolution determination unit 203,
The pointer data generation unit 302 selects a pointer image having a size corresponding to the resolution to generate pointer image data,
The generated pointer image data is written in the VRAM 304a.

A coordinate input device 30 with an operation switch is also provided.
When the "ON / OFF display of the pointer locus image" is instructed by the operation of the switch in 6, when the "ON / OFF display of the pointer locus image" is instructed, the locus of the pointer position data and the resolution determination result by the resolution determination unit 203 are displayed. On the basis, the locus data generation unit 303 selects a line having a thickness corresponding to the resolution to sequentially generate locus image data, and the generated locus image data is sequentially written in the VRAM 304b.

A coordinate input device 30 with an operation switch is also provided.
When the instruction of "OFF / display of pointer locus image" is given in the instruction of "ON / OFF of display of pointer locus image" by operating the switch in 6, the locus data generation unit 303 deletes the locus image data of the VRAM 304b. To do.

The teacher subsystem 30 sequentially processes each VRA.
The digital image data written in the M205a-205d and the pointer image data and the locus image data written in the respective VRAMs 304a-304b are read out. First, the digital image data is written only in the VRAMs 205a-205d.
A read operation in a state where image data is not written in b will be described.

Reading from each of the VRAMs 205a-205d uses a desired resolution generated by the read timing generator 207, and in this embodiment, the monitor CRT 211 of the teacher subsystem 30 has a screen of 1024 × 768 dots. The resolution is 1024 × 768 dots. Each VRAM 205a-205d
The digital image data read from is converted into an analog signal by the DA converter 206, and the selection unit 210
Sent to. The selection unit 210 selects and outputs the image signal output from the DA converter 206 according to the instruction of “multi-window display” input from the operation panel 209 via the control unit 208, and the monitor CRT 211.
The computer screens of the student subsystems 1a-1d are displayed for four images.

FIG. 2 shows an example of a screen display of the monitor CRT 211. (A) has a resolution of 640 × 480.
Dot student subsystem 1a computer image 50
1, (B) is a personal computer image 502 of the student subsystem 1b having a resolution of 640 × 400 dots, and (C) is an image 503 of the monitor CRT 211 of the teacher subsystem 30.
Then, the screen of 1024 × 768 dots is divided into four, and the upper left 503A, the upper right 503B, the lower left 503C, and the lower right 503.
Personal computer images of the student subsystems 1a-1d are displayed at the respective positions of D. Of these, the image of the student subsystem 1a in the upper left 503A is
640 × 480 dots are reduced to 512 × 384 dots, and the personal computer image of the student subsystem 1b in the upper right 503B has 640 × 400 dots reduced to 512 × 384 dots. Other images are also 512 × 38
It has been converted to a size of 4 dots.

Here, a personal computer image is transmitted from each student subsystem to monitor CR of the teacher subsystem.
About the operation until multi-window display on T,
Further details will be described.

Operation panel 20 of teacher subsystem 30
Input the execution instruction of "Student screen reception" from 9 and control unit 2
When a control signal is sent from 08 to each student subsystem, as shown in the timing chart of FIG.
Controls the student screen control unit 9 of each student subsystem 1a-1d in order at a predetermined time interval such as an interval of 1 second, for example.
0 to transmit. Whenever each personal computer image is received, the teacher subsystem 30 first determines the resolution of the personal computer image by the resolution determination unit 203 during the determination time t,
The write timing corresponding to the resolution, that is, the timing signal of reduction corresponding to the resolution (for example, 640 × 480 dots in the student subsystem 1a is reduced to 512 × 384 dots) is supplied as the write timing generation unit 204.
And sequentially write them in each VRAM 205a-205d.

Further, during the determination time t, the read timing generating section 207 generates the read timing, that is, the timing signal for displaying at each desired position (1024 × 768 dots) divided into four positions. Reading is started from each corresponding VRAM 205a-205d. Image display 503A-503D divided into four
Respectively correspond to the corresponding VRAMs 205a-205d.
While the writing and reading are being performed, the moving image of the student subsystem is displayed, and after switching to the next student subsystem, the image immediately before switching is displayed as a still image. If there are 5 student subsystems
In the above case, after displaying the personal computer images of the student subsystems 1a-1d, the student subsystems 1a in the upper left 503A are sequentially switched to and displayed on the personal computer images of the next student subsystem 1e.

Next, referring again to FIG. 1, the digital image data written in each VRAM 205a-205d of the teacher subsystem 30 and each VRAM 304a-3.
The operation of simultaneously reading the pointer image data and the trajectory image data written in 04b will be described.

The pointer image data of the VRAM 304a or the locus image data of the VRAM 305b is the VRAM.
When any one of the image data 205a to 205d (hereinafter, this one image data is referred to as VRAM 205x) is read, a timing at which the image data of the VRAM 205x is read, that is, a desired timing generated by the read timing generation unit 207. Resolution (1024 x 7
(68 dots) are read at the same time. That is, when the pointer image data is written in the VRAM 304a or the locus image data is written in the VRAM 304b, the respective pointer image data or locus image data is read so as to be combined with the image data in the VRAM 205x. .

FIG. 4 is a timing chart showing an input signal to the DA converter 206.
4A, the pointer image data of 4a, the locus image data of VRAM 304b, and the image data of VRAM 205x are sequentially read from the first pixel at the same timing. In FIG. 4, ◯ indicates that the pointer image data exists at the position of the corresponding pixel, Δ indicates that there is locus image data at the position of the corresponding pixel, and ● indicates the image data of the VRAM 205x at the position of the corresponding pixel. Indicates that there is. If the pointer image data is in the corresponding pixel, the pointer image data is read from the VRAM 304a, and if the corresponding pixel has the trajectory image data, the VRAM3 is read.
04b, the locus image data is read out, and when the pointer image data and the locus image data are neither pixels, the image data in the VRAM 205x is read out,
Transfer to the D-A converter 206.

Since the VRAM 304a and the VRAM 304b are read simultaneously at the timing of the desired resolution when the VRAM 205x is read, the VRAM 304a is read.
Of the pointer image data and the locus image data of the VRAM 304b are read after being enlarged or reduced to an appropriate size according to the desired resolution.

As described above, by synthesizing the three image data and inputting them to the DA converter 206, the digital image signal is converted into the analog type image signal,
The analog image signal input to the A / D converter 202 is combined with the pointer image data of the coordinate input device 306 with operation switch and its trajectory image data, and the combined image is displayed on the monitor CRT 2 via the selection unit 210.
11 will be displayed.

In the selection section 210, a personal computer image of each student subsystem input to the operational amplifier 201 or an instruction input "ON / OFF of marking image display" by operating a switch in the coordinate input device with operation switch 306. The coordinate input device 30 with operation switches is added to the image signal of the video device 300 input to the operational amplifier 308.
The image in which the pointer image data of 6 and the locus image data thereof are combined and the input image signal as they are are switched.

When an instruction to execute "send image to student" is input through the operation panel 209, the control unit 208 controls the selection unit 210 to output an image signal to the operational amplifier 307, and also for the student. The student screen control unit 9 in the subsystems 1a-1n is controlled. An image obtained by combining the pointer image data and the locus image data thereof is sent to the cable 10 via the operational amplifier 307, and the reception switching relay 400 is switched under the control of the student screen control unit 9 to change the pointer image data and the locus image data thereof. The combined image is a CRT for student subsystems 1a-1n
It is displayed in 5.

The operation of this embodiment has been described above. However, if the pointer data generation unit 302 is configured to have a plurality of pointer image data, the "pointer" is operated by operating a switch in the coordinate input device 306 with an operation switch. It is possible to change the type of pointer by the instruction of “switching type”.

As another example, the VRAM 304a,
By using the pointer image data and the trajectory image data written in the VRAM 304b as only drawing position data, drawing data such as brightness and color is added later to generate digital image data, and the digital image data is transferred to the DA converter 206. , VRAM 304a and VRAM 304b
It is also possible to reduce the capacity of the.

As another example, the VRAM 205a-
205d, the resolutions of the read timings from the VRAMs 304a-304b are all common, and for example, the resolution of the student subsystem 1a determined at the first determination time t (6
The VRAMs 205a to 205d of all the student subsystems may be read at the read timing obtained by reducing 40 × 480 dots to 512 × 384 dots). In this way, if all students use the same resolution computer in one computer education support system, the image of each student subsystem will have an aspect ratio that is the aspect ratio of the screen before and after reduction. Will be the same.

As described above, according to the present embodiment, the pointer image or the trajectory of the pointer from the coordinate input device with operation switch is added to the personal computer image of the student subsystem or the image of the video device as the teaching material presentation device. Since it is possible to synthesize images and display them on the CRT of the student subsystem, you can use the pointer image to mark arrows on the CRT of the student's personal computer or add the trajectory image as an underline. It becomes possible to perform the teaching from the teacher to the students more easily and efficiently.

Next, a second embodiment of the present invention will be described with reference to FIG.

In FIG. 5, components corresponding to those shown in FIG. 1 are designated by the same reference numerals or symbols, and their description will be omitted.

In the second embodiment of the present invention shown in FIG. 5, the operational amplifier 20 is used in the teacher subsystem 31.
The analog image signal input from the personal computer image of each student subsystem or the video device 300 via the operational amplifier 308 is input as an analog signal without being converted into a digital image by the AD converter. I am letting you. Then, the analog image signal and the output signal of the DA converter 206 are combined by the analog switch 601 and output to the selection unit 210.

The operation of the second embodiment shown in FIG. 5 is as follows.

The pointer data generation unit 302 generates pointer image data from the pointer position data input from the coordinate input device 306 with operation switches of the teacher subsystem 31 and writes it in the VRAM 304a. The locus data generation unit 303 also sequentially generates locus image data and sequentially writes the locus image data in the VRAM 304b. The operation up to this point is the same as in FIG.

Next, VRAM 304a and VRAM 304
The pointer image data and the locus image data written in b are converted into analog image signals by the D-A converter 206, and the analog pointer image data and the locus image data are stored in the teacher subsystem 31. The input analog image of the personal computer of the student subsystem 1a-1n or the analog image from the video equipment 300 as the teaching material presentation device is combined by the analog switch 601 and sent to the selection unit 210.
From the selection unit 201 to the CR of the student subsystems 1a-1n
Display at T5.

By configuring the teacher subsystem 31 with such a configuration, the AD converter 202 and the VRAM 205a-2 required in the first embodiment of the present invention.
It is possible to have a simple configuration that does not include 05d.

As another configuration, not only a personal computer image of the student subsystems 1a-1n or an image of the video equipment 300 as the teaching material presentation device but also an image of a personal computer for teacher (not shown) is input. May be. By doing so, the coordinate input device 30 with the operation switch
By drawing underlines etc. by 6 and displaying the screen on the CRT 5 of the student subsystem 1a-1n, which part of the screen information shown in the model is important, using the teacher's personal computer as a model You can teach effectively by pointing out whether there is something.

[0055]

As described above, the present invention, in the personal computer education support system, assists in explaining the image information displayed on the personal computer screen for students, the video equipment such as the teaching material presentation device, or the personal computer screen for teachers. For this reason, marking images such as arrows and underlines can be drawn from the teacher subsystem, and the images can be displayed on the CRT of the student subsystem, so that the teacher can effectively and more effectively teach the students. It has the effect that it can be performed.

Further, even if the CRTs of different personal computers have different resolutions, it is possible to display a pointer image and its trajectory image of an appropriate size at that resolution.

Further, in the personal computer education support system, since it is not necessary to limit the resolution of the personal computer CRT to one, it is possible to easily select and change the personal computer model when constructing the system. Has the effect.

Further, in the teacher subsystem, by reading the image signal from the video memory at the timing of one specific resolution, it is possible to display the image on the monitor CRT having one resolution, and the structure of the monitor CRT is changed. It has an effect that it can be simplified and provided at a low cost.

Further, the display of the marking image is turned on and off by the switch of the coordinate input device with the operation switch.
In the “F” operation, an image in which the pointer image of the coordinate input device with operation switch and its trajectory image are combined with the image signal input to the teacher subsystem, and the image signal that has been input to the teacher subsystem are combined. Since the switching is performed by the selection unit, the pointer image data and the trajectory image data are not erased, and there is an effect that the combined image can be easily recalled.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a personal computer education support system of the present invention.

FIG. 2 is a screen display example of a student subsystem and a teacher subsystem.

FIG. 3 is an operation timing chart of the embodiment of FIG.

4 is an operation timing chart of the DA converter according to the embodiment of FIG. 1. FIG.

FIG. 5 is a diagram showing a second embodiment of the present invention.

FIG. 6 is a block diagram showing an embodiment of a conventional personal computer education support system.

[Explanation of symbols]

1a-1n Student subsystem 2a-2n Student subsystem 4 Personal computer 5 CRT 6 Operational amplifier 7 Distributor 8 Transmission switching relay 9 Student screen control unit 10 Cable 11 Cable 20 Teacher subsystem 201 Operational amplifier 202 AD converter 203 Resolution Judgment unit 204 Write timing generation unit 205a, 205b, 205c, 205d VRAM 206 DA converter 207 Read timing generation unit 208 Control unit 209 Operation panel 210 Selection unit 211 Monitor CRT 30 Teacher subsystem 31 Teacher subsystem 300 Video Device 301 Scan converter 302 Pointer data generation unit 303 Trajectory data generation units 304a and 304b VRAM 305 Input selection relay 306 Coordinate input device 307 with operation switch 307 Operational amplifier 3 8 operational amplifier 400 receives the switching relay 501 for a PC monitor image 503 teacher subsystem 30 of the PC image 502 Student subsystem 1b of the student subsystem 1a CRT 2
11 images 601 analog switch

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Claims (3)

(57) [Claims] 1. A subsystem having a personal computer for a teacher and a personal computer for a plurality of students is connected by the same cable, and an image signal of the subsystem for each student is displayed on the subsystem for the teacher. In an image drawing method of a personal computer education support system, an analog image signal of each student subsystem received and input by the teacher subsystem or a video device such as a teaching material presentation device of the teacher subsystem. The analog image signal input from the above is converted into a digital image signal, the resolution of each image is determined by the synchronizing signal of the input analog image signal, and the timing signal generated according to the determined resolution is used. The digital image signal is stored in the first video memory, An image of a pointer whose position is indicated by a coordinate input device such as a mouse and a locus image of the pointer are stored in the second video memory and the third video memory by a timing signal generated according to the determined resolution. And the second video memory and the second video memory
Each of the 3 video memories has the resolution determined above.
The image of the pointer reduced or enlarged according to
Stores and locus image of the image with the pointer, and the first image signal and the pointer stored in the second video memory digitally stored in the video memory the image /
Alternatively, the trajectory image of the pointer stored in the third video memory is selected and read at a predetermined timing and converted into an analog image signal, whereby the input analog image signal is converted into an image of the pointer. Generates a composite image by combining with the trajectory image of the pointer,
An image drawing method for a personal computer education support system, characterized in that the composite image is transmitted to a student subsystem and displayed on a CRT of the student subsystem. 2. A personal computer in which each subsystem having a teacher personal computer and a plurality of student personal computers is connected by the same cable, and an image signal of each student subsystem is displayed on the teacher subsystem. In the education support system, the teacher subsystem includes a first operational amplifier that receives an analog image signal from the student subsystem, and an analog image signal from the first operational amplifier or the second operational amplifier. To an image signal of a digital system, a plurality of first video memories for storing image signals of a digital system corresponding to each of a plurality of divided multi-window screens, and the first video memory. An analog image signal from the operational amplifier or the second operational amplifier A resolution determining unit that determines the resolution of the signal, the resolution determined by the resolution determining unit, and the first
A plurality of the first operational amplifiers or the analog image signal synchronizing signal from the second operational amplifier.
Timing memory for controlling write timings to the second video memory and the third video memory, and a plurality of the first video memory, the second video memory, and the third video memory A DA converter for converting a digital image signal written in the analog image signal into an analog image signal, read timings from a plurality of the first video memory, the second video memory, and the third video memory A read timing generation unit for controlling the operation, an operation panel for receiving an execution instruction such as “student screen reception”, a control unit for controlling the execution instruction from the operation panel, and the first operational amplifier under the control of the control unit. Alternatively, by selecting either of the image signals of the output of the second operational amplifier and the output of the DA converter, And a video CRT for outputting a video image signal as a teaching material presentation device, and an analog video image signal from the video device. Scan converter for converting to a standard image signal, and the second for transmitting an image signal output from the scan converter
Operational amplifier, an input selection relay for switching between the analog image signal from the second operational amplifier and the analog image signal of the student subsystem from the first operational amplifier, input of coordinates, and "display of marking image". Coordinate input device with an operation switch including a mouse for instructing execution of “ON, OFF” and the like, and a pointer data generation unit for generating the shape of the pointer input from the coordinate input device with the operation switch via the control unit. And a locus data generation unit for generating a locus image of the pointer, the second video memory in which the pointer image data generated by the pointer data generation unit and the locus image data generated by the locus data generation unit are respectively stored, and The third video memory and the image signal selected by the selection unit are transferred to the student subsystem. It has a third operational amplifier to be transmitted to Temu, the second video memory and the third bidet
In the memory, the solutions determined by the resolution determination unit are respectively stored.
A pointer image that is reduced or enlarged according to the image resolution
A personal computer education support system characterized in that image data and trajectory image data are stored . 3. The read timing generator is specified
Generate a timing signal of a specified resolution, and
As a timing signal with a specific resolution, multiple student support
The timing of one resolution in the
Personal computer educational support system according to claim 2, characterized in that that.