JP2821390B2 - Image control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image control device for outputting digital image data received from a communication line or analog image data input from a video data output device to a display output device for display. The present invention relates to an image control device provided with an image abnormality detection circuit for detecting abnormality of image data such as color abnormality of an image, shaking, and distortion.

[0002]

2. Description of the Related Art The quality of a display image in a conventional image communication apparatus is determined by automatically detecting an abnormality in data recorded on a recording medium, such as a line scanning type image communication apparatus disclosed in Japanese Patent Application Laid-Open No. Hei 3-53763. It is used for the purpose of detection.

FIG. 2 is a block diagram showing an example of such a conventional image communication apparatus.

In FIG. 2, reference numeral 41 is a photomultiplier tube, 42 is a head amplifier for doubling the output of the photomultiplier tube 41, 43 is an analog controller for adjusting an analog signal from the head amplifier 42, and 44 is an analog controller. An A / D converter for converting an analog signal from 43 into a digital signal, an input-side line memory 45 for temporarily storing a digital signal from the A / D converter 44, and a control for the input-side line memory 45. An input side line memory controller 47 is an output side line memory for temporarily storing the image signal sent from the image signal control circuit, and 48 is a pulse for shaping the image signal pulse output from the output side line memory 47. A shaping circuit; 49, a modulation driver for driving the optical modulator 53; 50, an output line memory system for controlling the output line memory. A control unit 51 for synchronizing the input-side line memory control unit 46 and the output-side line memory control unit 50; a line unit 52 for receiving line data from the input-side line memory control unit 46 and the output-side line memory control unit 50 This is a comparison circuit for comparison.

[0005] The image communication apparatus thus configured operates as follows. That is, the analog signal output from the photomultiplier tube 41 is amplified by the head amplifier 42, adjusted by the analog control unit 43, converted to a digital signal by the A / D converter 44, and temporarily stored in the input line memory 45. It is stored. On the other hand, the image signal sent from the image signal control circuit is temporarily stored in the output side line memory 47. These input side line memories 45
The line data stored in the output-side line memory 47 is synchronized with the line and timing by the control unit 51 and is extracted by the input-side line memory control unit 46 and the output-side line memory control unit 50.
2 are compared. As a result, when the two line data match, it means that the recording has been performed well, and when the two line data do not match, it means that an abnormality has occurred in the recording, so that a warning is issued as a recording error. .

[0006]

The means for judging the quality of image recording of the line scanning type image communication apparatus as described above is as follows.
Since the abnormality of the recording data on the recording medium is detected in units of lines, it has a drawback that it cannot be used as an abnormality detecting means of a display output device for displaying a two-dimensional image.

In addition, since abnormalities in image data such as color abnormalities, shaking, and distortion of images cannot be detected, abnormalities such as color misregistration, shaking, and distortions of the display output device can cause the displayed image to be displayed by human eyes. In order to judge whether the cause of the abnormality is due to a defect in the input signal, a defect in the display output device, or a defect in the image control device. Is also difficult.

[0008]

An image control apparatus according to the present invention includes a receiving circuit for receiving digital image data from a communication line, and an analog-to-digital conversion circuit for converting analog image data input from a video data output device into a digital signal. A storage circuit that stores the digital image data received by the reception circuit or the digital signal input from the analog-to-digital conversion circuit for each of a red signal, a green signal, and a blue signal in pixel units; and the storage circuit. A digital-to-analog conversion circuit that converts the stored red signal, green signal, and blue signal into analog signals and outputs the analog signals to a display output device, and digital image data that is input as an output signal from the storage circuit and serves as a reference. First alarm signal when compare and they do not match A digital abnormality detection circuit that outputs an output signal, and an analog abnormality detection circuit that receives an output signal from the digital-to-analog conversion circuit, compares it with reference analog image data, and outputs a second alarm signal when they do not match. In particular, a first comparison data storage circuit storing reference digital image data, and an output signal from the storage circuit is input and compared with the data of the first comparison data storage circuit. A digital abnormality detection circuit having a digital comparison circuit that outputs a first alarm signal when they do not match, or a second comparison data storage circuit storing reference analog image data; The output signal from the conversion circuit is input and compared with the data of the second comparison data storage circuit. Those with analog abnormality detection circuit having an analog comparator circuit for outputting an alarm signal.

[0009]

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

FIG. 1 is a block diagram showing one embodiment of the present invention.

The image control device 20 shown in FIG.
, An analog-to-digital conversion circuit (A / D conversion circuit) 4 for converting analog image data input from the video data output device 10 into a digital signal, and a digital signal received by the reception circuit 1. A storage circuit 2 for storing image data or a digital signal input from the A / D conversion circuit 4 for each of a red signal, a green signal, and a blue signal (RGB signal) for each pixel, and an RGB signal stored in the storage circuit 2 Is converted into an analog signal and output to the display output device 9 in addition to a digital-to-analog conversion circuit (DA conversion circuit) 3 and an image abnormality detection for judging the cause when an abnormality occurs in the display image. The circuit 21 is provided.

The image abnormality detection circuit 21 includes a digital abnormality detection circuit 22 and an analog abnormality detection circuit 23. The digital anomaly detection circuit 22 includes a comparison data storage circuit 5 that stores digital image data designated in advance for each of the RGB signals in pixel units, an RGB signal in pixel units output from the storage circuit 2, A digital comparison circuit 6 compares the RGB signals in pixel units output from the comparison data storage circuit 5. The analog abnormality detection circuit 23 includes a comparison data storage circuit 7 that stores analog image data specified in advance for each of the RGB signals in pixel units, and a pixel unit output from the DA conversion circuit 3. An analog comparison circuit 8 compares the RGB signals with the RGB signals in pixel units output from the comparison data storage circuit 7.

Next, the operation of the image control device 20 configured as described above will be described.

The storage circuit 2 stores the output signal of the receiving circuit 1 that has received the digital image data from the communication line 13 as a plurality of bit data for each of the RGB signals for each pixel. The storage circuit 2 also includes a video data output device 1
A signal obtained by converting the analog image data output from 0 into a digital signal in the A / D conversion circuit 4 is also stored as a plurality of bit data for each of the RGB signals in pixel units. The signal output from the storage circuit 2 is sent to the D / A conversion circuit 3 and also sent to the digital comparison circuit 6 of the digital abnormality detection circuit 22 at the same time. Digital comparison circuit 6
Inputs a signal from the storage circuit 2 and an output signal of a comparison data storage circuit 5 which stores digital image data specified in advance for each of RGB signals in pixel units, and compares them. When a mismatch is detected, an alarm signal 11 is output.

The DA converter 3 converts the output signal of the storage circuit 2 into an analog signal and outputs the analog signal to the display output device 9 and, at the same time, outputs the analog signal to the analog comparison circuit 8 of the analog abnormality detection circuit 23. The analog comparison circuit 8 compares the signal from the DA conversion circuit 3 with the output signal of the comparison data storage circuit 7 which stores analog image data specified in advance for each RGB signal in pixel units. Input and compare them to detect a mismatch, alarm signal 1
2 is output.

When the alarm signal 11 is output, the digital image data received from the communication line 13 is abnormal, or color misregistration, shaking, or distortion is caused by abnormality in the receiving circuit 1 or the storage circuit 2. It can be determined that this has occurred.

When the alarm signal 12 is output, the analog image data output from the video data output device 10 is abnormal, or the reception circuit 1 or the storage circuit 2
Alternatively, it can be determined that a color abnormality has occurred due to an abnormality occurring in the DA converter circuit 3.

Alarm signal 11 and alarm signal 12
Are not output, and furthermore, if there is an abnormality in the image displayed on the display output device 9, it can be determined that an abnormality has occurred in the display output device 9.

[0019]

As described above, the image control apparatus of the present invention compares the digital data of the image data to be displayed and output with the reference digital image data, and outputs an alarm signal when they do not match. By providing a digital abnormality detection circuit for comparing the analog data of the image data to be displayed and output with the reference analog image data, and providing an analog abnormality detection circuit for outputting an alarm signal when they do not match, an image is provided. This makes it possible to detect abnormalities in image data such as color abnormalities, shaking and distortion. Another effect is that it is possible to determine whether the cause of these abnormalities is due to a defect in the input signal, a defect in the display output device, or a defect in the image control device.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a block diagram illustrating an example of a conventional image communication device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Receiving circuit 2 Storage circuit 3 Digital-to-analog conversion circuit (DA conversion circuit) 4 Analog-digital conversion circuit (AD conversion circuit) 5.7 Comparison data storage circuit 6 Digital comparison circuit 8 Analog comparison circuit 9 Display output device 10 Video data output device 11/12 Alarm signal 13 Communication line 20 Image control device 21 Image abnormality detection circuit 41 Photomultiplier tube 42 Head amplifier 43 Analog control unit 44 A / D converter 45 Input side line memory 46 Input side line memory control unit 47 Output-side line memory 48 Pulse shaping circuit 49 Modulation driver 50 Output-side line memory control unit 51 Control unit 52 Comparison circuit 53 Optical modulator

Claims (3)

(57) [Claims] 1. A receiving circuit for receiving digital image data from a communication line, an analog-to-digital conversion circuit for converting analog image data input from a video data output device into a digital signal, and the digital image data received by the receiving circuit Or a storage circuit that stores the digital signal input from the analog-to-digital conversion circuit for each signal of a red signal, a green signal, and a blue signal in pixel units, and the red signal, the green signal, and the A digital-to-analog conversion circuit that converts a blue signal into an analog signal and outputs it to a display output device, and compares an input signal from the storage circuit with reference digital image data, and when they do not match, a first A digital abnormality detection circuit for outputting an alarm signal; An image control device comprising: an analog abnormality detection circuit that receives an output signal from a digital-to-analog conversion circuit, compares analog image data serving as a reference, and outputs a second alarm signal when they do not match. . 2. A first comparison data storage circuit storing reference digital image data, and an output signal from the storage circuit is input and compared with the data of the first comparison data storage circuit to make them compare. 2. The image control device according to claim 1, further comprising: a digital abnormality detection circuit having a digital comparison circuit that outputs a first alarm signal when the values do not match. 3. A second comparison data storage circuit storing analog image data serving as a reference, and an output signal from a digital-to-analog conversion circuit is input and compared with data in the second comparison data storage circuit. 3. The image control device according to claim 1, further comprising an analog abnormality detection circuit having an analog comparison circuit that outputs a second alarm signal when they do not match.