JPH0377088A - Digital scan converter - Google Patents

Abstract

PURPOSE:To record a display video signal on an inexpensive digital memory without requiring any high-band VRT device by providing the digital scan converter with an interface part for an external digital recorder. CONSTITUTION:The digital scan converter performs scan conversion from a radar video signal to a TV scanning system. The interface part 7 constitutes an output part for recording digitized video data and this output part is provided on an input buffer 2. This constitution quantizes the radar video signal (a) by an A/D converting circuit 1 firstly to obtain a digital video signal (b) and data of one sweep is stored in the buffer 2. The stored data are written in an image memory 3 in order and also inputted to the interface part 7 for the external digital recorder. This interface part 7 performs level conversion and format conversion and sends the result out to the external digital recorder.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention displays radar video signals using PPI (Plan
The present invention relates to a radar digital scan converter that converts scanning to TV constant scan, and particularly relates to a digital scan converter for realizing a digital video data recording method of a radar digital scan converter.

[Conventional technology]

An example of a conventional digital scan converter is shown in FIG. 3 and will be described.

In the figure, 21 is an A/D conversion circuit for digitizing the radar video signal, 22 is an input buffer, 23 is an image memory for storing digital video data, 24 is an output terminal, and 25 is an The output controller 26 is a scan conversion circuit.

And, l indicates a radar video signal, j is a digital video signal, k is a radar azimuth signal and a trigger signal, and t
is a memory address signal, m is a TV synchronization signal, n is digital video data, and O is a display video.

The principle of the digital scan converter shown in Fig. 3 was published by the Institute of Electronics, Information and Communication Engineers (January 1982).
Based on "Radar Technology" P2O5, Figure 7.11, published on May 20th.

Next, the operation of the digital scan converter shown in FIG. 3 will be explained.

First, the radar video signal l is quantized by the A/D conversion circuit 21, and the data for one sweep is stored in the input buffer 22 as a digital video signal j. and,
The data stored in this manual buffer 22 is sequentially written into the image memory 23.

Next, in reading, the image memory 23 is operated in accordance with the radar azimuth signal input to the scan conversion circuit 26 and the memory address signal t created by the trigger signal k.
One scanning line of data is read from the output buffer 24.
It stores the data and sends the data to the output controller 25.
The D/A converted display video 0 is output. At the same time, the scan conversion circuit 26 outputs a 5'l'v synchronizing signal m.

When recording this display video 0, the VTR
A device (not shown) will record the displayed video O by means of a TV synchronization signal m.

[Problem to be solved by the invention]

The conventional digital scan converter described above is configured as described above, so if the frequency characteristics of the displayed video are in a high band, or if the TV synchronization signal is different from the general TV synchronization signal, However, there was a problem in that a general TV VTR device could not be used to record the displayed video, and a special VTR device was required.

The present invention was made in order to solve this problem, and an object of the present invention is to provide a digital scan converter that can record display video without requiring a special VTR device.

[Means to solve the problem]

The digital scan converter according to the present invention is a digital scan converter that scan-converts a radar video signal into a TV scanning system, and is provided with an output section on the input side 7a for recording digitized video data. .

[For production]

In this invention, the quantized radar video signal is output to the output of the input buffer to the digital memory for recording on a digital recording device.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing an embodiment of a digital scan converter according to the present invention.

In the figure, 1 is an A/D conversion circuit for digitizing radar video signals, 2 is an input buffer, 3 is an image memory for storing digital video data, 4 is an output buffer, 5 is an output controller, 6 is a scan conversion circuit, 7
This is an interface unit necessary for recording digital video data f into a digital recording device (not shown).

The digital scan converter shown in the embodiment of FIG. 1 is configured to perform scan conversion of a radar video signal into a TV scanning system, and the casing and interface section T are for recording digitized video data. It constitutes an output section, and this output section is provided in the input buffer 2.

The island indicates a radar video signal, b indicates a digital video signal, C indicates a radar azimuth signal and trigger signal, d indicates a memory address signal, e indicates a TV synchronization signal, f indicates digital video data, and g indicates display video.

Next, the operation of the embodiment shown in FIG. 1 will be explained.

First, a radar video signal a is quantized by an A/D conversion circuit 1, and data for one sweep, which is a digital video signal, is stored in an input buffer 2.

Next, the data stored in the input buffer 2 is sequentially written into the image memory 3, and is also input to the interface unit 7 with an external digital recording device. The interface section T then performs level conversion and format conversion, and sends the signal to an external digital recording device, where it is written and records the radar video signal a without the need for a special VTR device or the like.

In the above embodiment, only the interface section to the external digital recording device is provided, but a selection circuit 8 is provided before the image memory 3 so that the memory data h from the external digital recording device can be input to the image memory 3. You can. Hereinafter, FIG. 2 showing the above modification will be explained.

FIG. 2 is a block diagram showing another embodiment of the invention.

In FIG. 2, the same reference numerals as those in FIG. The selected output is configured to be supplied to the image memory 3.

Next, the operation of the embodiment shown in FIG. 2 will be explained.

First, a radar video signal a is quantized by an A/D conversion circuit 1, and data for one sweep is stored in an input buffer 2 as a digital video signal. One of the stored data is input to the selection circuit 8, and the other is also input to the interface section T with an external digital recording device. Recorded data from an external digital recording device is also input to this interface section T, undergoes format conversion and level conversion, and is returned to the same format or level as the original digital video data f. This is also input to the selection circuit 8 as data h. Therefore, one of them is selected and written into the image memory 3.

Next, in reading, data for one scanning line is read out from the image memory 3 in accordance with the radar azimuth signal input to the scan conversion circuit 6 and the memory address signal d which is generated by the trigger signal C, and is output. Store this data in buffer 4 and send the data to output controller 5, D/A
It is converted and output as a display video g. At the same time, a fiTV synchronization signal is input to the scan conversion circuit 6.

In the embodiment shown in FIG. 2, by providing a selection circuit in front of the image memory, it is possible to easily reproduce past video data recorded in an external digital recording device by successively switching the selection section. effective.

〔Effect of the invention〕

As explained above, in this invention, since the digital scan converter is provided with an interface section to an external digital recording device, display video can be recorded using an inexpensive digital memory without requiring a high-bandwidth VTR device. There is an effect that can be done.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of a digital scan converter according to the present invention, FIG. 2 is a block diagram showing another embodiment of the invention, and FIG. 3 is a block diagram showing an example of a conventional digital scan converter. It is. 1...A/D conversion circuit, 2...input buffer,
3... Image memory, 4... Output buffer, 5...
...output controller 6 II...scan conversion circuit, 7.
...Interface section, 8...Selection circuit.

Claims (1)

[Claims] 1. A digital scan converter for scan-converting a radar video signal into a TV scanning system, characterized in that an input buffer is provided with an output section for recording digitized video data.