JPS6366094B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement in an infrared imaging device that observes the temperature distribution of an object by detecting infrared radiation depending on the surface temperature of the object. In particular, the present invention relates to an infrared imaging device that is convenient for use in observing temporal changes in the surface temperature of a human body.

[Conventional technology]

Infrared imaging devices that detect and visualize the infrared rays emitted by an object to observe the temperature distribution on the surface of an object have been well known for a long time. can be observed, so it is widely used for industrial and medical purposes. By the way, medical infrared imaging devices not only measure the temperature distribution on the surface of the human body, but also
It is required to know the amount of change in temperature over time at the same location. For example, as shown in Japanese Patent Application Laid-Open No. 120480/1983, it is necessary to calculate the difference between two infrared images taken at a certain time interval. It has been proposed to display the results as a first-order differential image.

However, in order to accurately calculate the difference in the amount of change over time, it is important to accurately overlap the two image data, and conventionally it was necessary to fix the relative position between the subject and the infrared camera. It was hot.
For this reason, it was unavoidable that it was inconvenient to use, such as restricting the movement of the subject.

[Problem that the invention seeks to solve]

Therefore, it is an object of the present invention to provide an infrared imaging device that does not cause the above-mentioned inconveniences in photographing. The aim is to provide infrared imaging devices that can be easily stacked together to obtain accurate data and improve operability.

[Means for solving problems]

Briefly, in order to achieve the above-mentioned object, the present invention temporarily stores photographed infrared image data in an external memory, extracts data showing the outline of the image, and stores it in another memory.
The infrared image taken after a predetermined period of time and the outline pattern of the preceding image are displayed superimposed, the memory address of the outline pattern is moved and adjusted so that their outlines match, and the information corresponding to the amount of movement is used to display the outline pattern of the preceding image. The feature is that two infrared images are superimposed by moving memory addresses.

[Effect]

That is, in a digital memory type infrared imaging device, an analog video signal from an infrared camera is converted into a digital signal to perform various image processing, and the above-mentioned difference calculation is also performed digitally. In this case, in this invention, instead of fixing the relative position of the object and the camera and photographing it, the contour pattern of the image once photographed is moved in memory and superimposed on the contour of the image photographed after a predetermined period of time. This automatically matches the corresponding positional relationship between the two images. Therefore, restraint on the subject can be minimized, making it even easier to use.

〔Example〕

Preferred embodiments of the present invention will be described in more detail below with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of an example of an infrared imaging device to which the present invention is applied. An infrared camera 1 includes a scanning optical system 2, an infrared detector 3, and a preamplifier 4. The analog video signal from the camera 1 is converted into a digital signal by the A/D converter 5 and sequentially stored in the image memory 6 for one screen, and simultaneously written into the external image memory 8 through the main control unit 7 including a microcomputer. .
Further, the digital image data is processed by the contour extraction circuit 9.
, and sequential difference calculations are performed between the previously stored adjacent pixels and the difference data exceeding a predetermined threshold is stored in the contour memory 10 as data representing the contour pattern.

On the other hand, a comparison memory 1 is placed in parallel with the image memory 6.
1, into which the contents of the external image memory 8 or the contents of the contour memory 10 are loaded at any time. The pattern data loaded into the comparison memory is configured so that its memory address can be moved by operating a movement adjusting means 12 such as a joystick. In addition, an X-axis movement register 13 and a Y-axis movement register 14 are used to temporarily store the amount of image movement by the movement adjustment means.
is attached.

The outputs of the image memory 6 and comparison memory 11 are written to the screen memory 16 again through a data selector 15 having an arithmetic function. The video signal read from the screen memory is applied to a display such as a CRT (cathode ray tube) through a D/A converter 17 and a video control circuit 18, and images are displayed at a normal television frame cycle.

Now, in the above-described configuration, the first image data of the subject 20 photographed at a certain time t1 is first stored in the image memory 6 and displayed as is on the CRT display 19.
The image is displayed on the screen and also stored in the external image memory 8. At the same time, contour data paired with the first image data is extracted and stored in the contour memory 10. Next, at time t2 after a predetermined period of time has elapsed, the same part of the same subject is imaged and the contents of the image memory 6 are rewritten with the second image data at that time, and the surface screen of the CRT display is switched to the second image. Further, this second image data is also written to another area of the external image memory 8 through the main control section 7 together with the contour data of the image.

When observing partial temperature change data by calculating the difference between the temperature data of the first image and the second image, the data of the contour memory 10 is stored in the comparison memory 11 in response to an external command signal S1. be transferred. Then, the data selector 15 combines the second image in the image memory 6 and the contour data of the first image stored in the comparison memory, and writes the synthesized image into the screen memory 16, so that the combined image is displayed on the display 19. Become. Then, while observing this composite display screen, the operator adjusts the movement adjusting means 12 for moving the contour so that the contour pattern of the first image matches the contour line of the second image. After confirming that the two match, the calculation command signal S2 is generated by pressing the button.
When inputting , the contents of the comparison memory 11 are rewritten with the first image data of the external image memory 8 that is paired with the previous contour data. At this time, the address of the first image data written to the comparison memory is
The contents of the X-axis movement register 13 and Y-axis movement register 14 stored in correspondence with the adjustment amount of the movement adjustment means 12 are shifted from the initial values and stored. Therefore, the first image in the comparison memory 11 and the second image in the image memory 6 after the rewriting is completed.
Since the image automatically has an address corresponding to the imaged part of the subject, there is no need to restrain the subject as in the past so that the imaged part does not shift.

Thus, in the above state, the data at the corresponding addresses in the image memory 6 and the comparison memory 11 are
Pixel by pixel is read out sequentially, a difference is calculated by the data selector 15, and the results are sequentially stored in the screen memory 16. Since the result of the difference calculation indicates the amount of temperature change for each pixel, by displaying the contents of the screen memory 16, it is possible to observe the temporal temperature change amount pattern of the entire imaged area.

FIG. 2 is an image diagram showing the mode of position alignment when observing a human hand as the imaged object 0J.
At t1, the contour pattern H1 of the first image photographed earlier is synthesized and displayed, and the contour pattern H1 is moved and adjusted as shown by the arrow to be superimposed on the second image H2.

In the above embodiment, the image memory 6, the comparison memory 11, and the screen memory 16 are shown as separate structures, but in reality, it is a matter of course that a plurality of areas of the common memory are used for each function. Contour memory 10 also shown as part of the external memory
may be omitted depending on the case, and the comparison memory 11 may have this function. In other words, if the previous image data is read from the external image memory, the contour is extracted, and the result is written directly to the comparison memory 10 each time the image overlap is adjusted, the same adjustment can be made without an independent contour memory. be.
Furthermore, the target for extraction of contour data does not necessarily have to be the preceding image data, and the memory arrangement may be changed so as to adjust the contour pattern position of the subsequent image based on the preceding image.

〔Effect of the invention〕

As is clear from the above description, in short, the present invention provides, when two infrared image data taken at a predetermined time interval are superimposed on each other at the same location, the outline pattern of one image is extracted for adjustment. The main idea is to pair it with the other image and align it with the other image.
In addition to eliminating the need to impose extra constraints on the subject, positioning is performed using outline patterns, making it easy to see and extremely simple to operate. Therefore, this invention
It is particularly effective when applied to infrared imaging devices that observe changes in temperature over time to ensure data accuracy and improve operability.

[Brief explanation of drawings]

FIG. 1 is a main part block diagram showing a schematic configuration of an example of an infrared imaging device according to the present invention, and FIG. 2 is an image diagram illustrating a mode of positioning operation. In the figure, 1 is an infrared camera, 6 is an image memory, 7 is a main control unit, 8 is an external image memory, 9 is an outline extraction circuit, 10 is an outline memory, 11 is a comparison memory, 12 is a movement adjustment means, and 13 is an X An axis movement register, 14 a Y-axis movement adjustment register, 15 a data selector, 16 a screen memory, 18 a video control circuit, 19 a display, and 20 an object to be imaged.

Claims (1)

[Claims] 1. A first storage means for storing an infrared image depending on the temperature distribution of the object, a second storage means for storing a preceding image taken a predetermined time before the time at which the infrared image was taken, and one of the images. and a third storage means for extracting the contour of the image and storing the contour pattern at a position corresponding to the address of the image, the contour pattern stored in the third storage means and the first or second storage. A display is provided for displaying the other infrared image stored in the means on a common screen, and a movement adjusting means for adjusting the position of the contour pattern is connected to the third storage means, After displaying the contour pattern of one image superimposed on the other infrared image by adjusting the adjustment means, movement information corresponding to the amount of movement of the contour pattern set by the movement adjustment means is stored in the other infrared image. An infrared imaging device characterized in that the positions of two infrared images taken at a predetermined time interval can be matched by inputting the information to the first or second storage means.