JPS61269582A - Scan conversion system for infrared-ray video device - Google Patents

Abstract

PURPOSE:To simplify a write/read-out timing circuit, and to improve the reliability by writing the contents of a buffer memory for video signal in a video memory by a vertical blanking detecting output. CONSTITUTION:A video signal from an infrared-ray camera 1 is stored in a video memory 4 through a buffer memory 3, and a picture display is executed by a TV monitor 8. In this case, by a rise of a blanking signal which has been detected by a vertical blanking detecting circuit 12, its write is indicated to a selector 6, and it is indicated to the memory 3 to transfer its stored data to a memory 4. Also, by a fall of the blanking signal, read-out is indicated to the selector 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] This is a scan conversion method in which the write timing of an infrared video device that alternately writes and reads video signals to and from a video memory is set to the blanking time of a vertical synchronization signal of a TV monitor.

[Industrial application field]

The present invention relates to an infrared imaging device, and more particularly to a scan conversion method in which the timing of writing a video signal into a video memory is at the blanking time of a vertical synchronization signal of a TV monitor.

[Conventional technology]

Currently, in infrared imaging devices, since the infrared camera scanning speed and the TV monitor scanning speed are different, scanning conversion is performed using a -BIC memory or the like.

FIG. 3 shows a block diagram of a conventional infrared imaging device. In the figure, reference numeral 1 photographs an object (not shown) with an infrared camera, outputs the video signal, and digitizes it with an A/D converter 2 to create video data.

The video data is temporarily stored in the buffer memory 3. Reference numeral 4 denotes a video memory, which has a capacity to store video data for one screen of a TV monitor. Reference numeral 5 denotes an address generation unit that specifies the storage position of video data in the video memory 4 using vertical and horizontal synchronization signals obtained from the vibrating mirror drive unit of the infrared camera, and the address generated here is sent to the selector 6.
is man-powered.

7 is a D/A converter that converts the video data output from the video memory 4 into a video signal to be displayed on the screen of the TV monitor 8, which is modulated by the output of the TV synchronization signal generator 9, and then displayed on the screen of the TV monitor 8. will be displayed.

Further, the address for reading the video data from the video memory is the vertical address for TV output from the TV synchronization signal generator 9,
A horizontal synchronizing signal is generated by the TV child address generator 10 and input to the selector 6.

11 is a horizontal blanking detection circuit that detects the blanking time included in the horizontal synchronizing signal output from the TV synchronizing signal generator 9; At the rising edge of the blanking signal detected by the horizontal blanking detection circuit 11, the selector 6 is instructed to write, and the buffer memory 3
The controller instructs to transfer the stored data to the video memory 4. Further, when the blanking signal falls, the selector 6 is instructed to read.

FIG. 4 shows an explanatory diagram of a conventional scan conversion method.

The figure explains the timing using the Japanese standard TV standard as an example.

In the figure, the horizontal blanking time included in the TV horizontal synchronization time of 65.5 μs is 4.8 μs.
．． Writing W of video data was performed every 8 μs blanking time, and reading R of video data was performed every remaining time.

[Problem that the invention seeks to solve]

According to the conventional method, the writing time per write is too short1
．． Moreover, since it is distributed, it is difficult to determine the timing of writing, and there is a drawback that too much wasted time is accumulated.

Another drawback is that it requires a complicated circuit to create write timing.

The present invention was created in view of the above-mentioned conventional drawbacks, and an object of the present invention is to provide a scan conversion method that can easily obtain write timing with a simple circuit.

[Means to solve the problem]

The scan conversion method of the infrared imaging device of the present invention is as shown in the configuration diagram in FIG. 1 and the method explanatory diagram in FIG.
In an infrared imaging device that stores a video signal outputted by a video signal in a video memory 4 via a buffer memory 3 and displays the screen on a TV monitor 8, the blanking time of the vertical synchronization signal of the TV monitor 8 is displayed on the TV monitor 8. A vertical blanking detection circuit 12 is provided to detect the content of the buffer memory 3 using the output of the vertical blanking detection circuit 12.
It is characterized in that it is written into the video memory 4.

[Effect]

The standard 60Hz TV vertical synchronization signal is used, and its blanking time is shorter than that of the horizontal synchronization signal, and the horizontal synchronization signal of the vibrating mirror of current infrared cameras is mainly used at 60 or 120. Because I have
Writing control can be easily made more efficient by writing data for one or two horizontal scans of the vibrating mirror into the video memory 4 via the buffer memory 3 at once during the vertical blanking period.

〔Example〕

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

In order to make the explanation of the configuration and operation easier to understand, the same parts are given the same reference numerals throughout the drawings, and their repeated explanation will be omitted.

FIG. 1 shows an explanatory diagram of an embodiment of an infrared imaging device according to the present invention. In the figure, reference numeral 12 denotes a vertical blanking detection circuit that detects the blanking time included in the vertical synchronizing signal output from the comrade signal generator 9.

At the rise of the blanking signal detected by the vertical blanking detection circuit 12, the selector 6 is instructed to write, and the buffer memory 3 transfers the stored data to the video memory 4! 1- Instruct to do something. Further, when the blanking signal falls, the selector 6 is instructed to read.

FIG. 2 shows an explanatory diagram of the scan conversion method of the present invention.

In the figure, the vertical blanking time included in the TV vertical synchronization time of 16.7ms is 589.5μS.
The video data is written W every 89.5 μS blanking time, and the video data is read R every remaining time.

One horizontal scanning time of the vibrating mirror of infrared camera 1 is 16.7
n+s (60Hz) or 8.3m5 (120Hz)
is the mainstream, it is easy to synchronize with the TV vertical synchronization signal, and scanning efficiency can be improved by writing video data for one or two horizontal scans of the vibrating mirror into the video memory 4 via the buffer memory 3 at once. improves. Furthermore, since the written video data is grouped together, it is easy to control the memory using a microcomputer.

Furthermore, compared to the conventional method, the delay in writing can be completely ignored.

〔Effect of the invention〕

As described above in detail, according to the scan conversion method of the infrared imaging device of the present invention, the circuit for obtaining the timing of writing and reading from the video memory is simplified, which is effective in improving the reliability.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of an embodiment of an infrared imaging device of the present invention. Fig. 2 is an explanatory diagram of a scan conversion method of the invention. Fig. 3 is a block diagram of a conventional infrared imaging device. Fig. 4 is a diagram of a conventional infrared imaging device. An explanatory diagram of the conversion method is shown. In the figure, l is an infrared camera, 3 is a buffer memory,
4 is a video memory, 8 is a TV monitor, and 12 is a vertical blanking detection circuit. Figure 4

Claims (1)

[Claims] An infrared imaging device that stores a video signal output from an infrared camera (1) in a video memory (4) via a buffer scale (3) and displays it on a TV monitor (8), comprising: The TV monitor (8) is provided with a vertical blanking detection circuit (12) for detecting the blanking time of the vertical synchronization signal of the TV monitor (8), and the vertical blanking detection circuit (
12), the contents of the buffer memory (3) are
A scan conversion system for an infrared imaging device, characterized in that writing is performed in the video memory (4).