JPS60120273A - Target position detecting apparatus - Google Patents

Abstract

PURPOSE:To attain to accelerate the detection speed of a target and to enhance the tracking capacity of said target by reducing a correlation operating time, by compressing data by providing an adder circuit for adding picture elements of a picture cut off by gates in horizontal and vertical directions. CONSTITUTION:An image signal is subjected to A/D conversion and a picture 16 is cut off by the first gate 15 of a gate circuit 4 and, in the succeeding picture, a picture 18 is cut off by the second gate 17 of a gate circuit 5. In this case, the data of the picture 16 is compressed by an adder circuit 19 and, similarly, the data of the picture 18 is compressed by an adder circuit 20. The compressed data are stored in memories 21, 22 and operation is performed in a correlation operating circuit 8 by using these compressed data. Therefore, a correlation operating time is reduced to accelerate the detection speed of a target and the tracking capacity of the target can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a detection device that detects a target position using correlation calculation.

In conventional devices of this kind, there has been a first-order type.

FIG. 2 is a diagram showing an example of the configuration of a conventional device.
1) is a video signal, (2) is an A/D converter, (3) is a switch, +41. +51 is a gate circuit, +61. (
71 is a memory, (8) is a correlation calculation circuit, (9) is a correlation coefficient signal, αα is a gate shift circuit, OD is a gate position signal, (12+ is a correlation coefficient judgment circuit, and α is a target position signal. .

The video signal (1) is converted into a digital signal by an A/D converter (2). On the initial screen, the switch (3) is connected to the terminal l side, and the image inside the gate is cut out by the manually set gate circuit (4) surrounding the target.

Stored in memory (6).

From the next screen, the switch (3) is connected to the terminal 2 side.

FIG. 2 is a diagram showing the relationship between the 0 screen and the first and second gates, where 04J is the screen and 05J is the first game)
, (161 is the image cut out at the lth gate, Q7+
is the image extracted by the second gate, and aa+ is the image extracted by the $2 gate.

In the following screen, the 9th order correlation coefficient is calculated using the image cut off at one setting position of (2nd game) (17+).

Now, the image side cut out by the first gate is lai, j1
1≦i≦m, 1≦j≦n), the image cut out by the second gate is (bi 10, j+ell≦i≦m, 1≦j≦
n).

Here, tk and I represent the position of the second gate.

For example, lk, /l= (0,01 indicates that the second gate is in the upper left corner of the diagram.

At this time, the 9th order correlation coefficient Ck, e is calculated by the correlation calculation circuit (8
) is calculated.

Ck, e= J ”E l bi+, j+e−a
i, jl −−−−1l13=l 1=1 When Ck, e is found in one (k, e), the gate shift circuit shifts the second gate position to l−+1+1 and If the second gate position reaches the right edge of the screen α, then -+ +1. /→Move the second gate position to 0, and at the new position, the correlation coefficient is the same as C
Two required.

Figure 3 shows an example of the distribution of Ck and e at each position, k = kt, 1 = ls odor C, picture Q81 matches best with picture u61, and then Ck , e indicates the decimal value.

The correlation coefficient signals representing Ck and e are processed by a correlation coefficient determination circuit (
2), and at the same time, a gate position signal aυ representing (k, el) is input, where Ck, e becomes the minimum (k, el) is detected and output as a target position signal αJ. .

This target position signal u3 is an image of the target to be tracked (161
This is the signal that indicates the position of the image that is most consistent with the .

If this signal is input to, for example, a servo mechanism that controls the optical axis direction of the imager, the target will be tracked.

By the way, in the conventional device of this type, in the calculation of equation (1), (nXm3 additions and subtractions and absolute value conversion are required, and (kxe1 calculation of (11) are required.

For example, m−n=30. If = e = 30, then 8. l
X10' times (addition, ten subtraction + absolute value operation) are required.

Even if the time for each calculation is 1 microsecond, it takes 0.8 seconds to calculate all Ck and e.
It can be seen that tracking the target in real time becomes extremely difficult or impossible.

The present invention provides a means to eliminate these drawbacks through data compression, as described below.

The present invention will be described in detail with reference to the drawings.

FIG. 4 is a diagram showing one embodiment of the configuration of the present invention, in which a (branch), , the process in which both heads are cut off by the l-th gate aω by the gate circuit (4) in the initial screen, and in the subsequent screen.

The process in which both ends are cut off by the gate circuit (5) and the second gate α7) is the same as in the conventional device.

The explanation will be omitted.

FIG. 5 is a diagram showing a data compression method.

Both ends (ai, jll≦
i≦m.

l≦J≦n) is compressed into ζ21st order data (pill≦i≦m) and (q111≦j≦n) in the adder circuit U bottle as shown in the fifth factor (Xu).

Similarly (2. Image Q8 cut out by gate circuit (5)) (
bi+, j ten e l l≦i≦m, t≦j≦n)
is 0 in the adder circuit ■, as shown in FIG. 5(b).
The following data (ui 11≦i≦ml, and ('j I
1≦j≦n).

FIG. 6<8) and (b) show the storage of compressed data in memory (2) and (2), respectively.
It is a figure which shows an example. As a result of data compression, the capacity required for memory is reduced from the conventional (iXj) pixels to
+i+j) pixels.

In the correlation calculation circuit (8), zero-order calculation is executed using these compressed data.

The correlation coefficient signal (9) obtained by the calculation of the above equation is input to the correlation coefficient determination circuit 0, as in the conventional device.

(k, e) at which Dk, e is the minimum is detected, and the target position is detected.

By the way, if we count the number of operations in equation (6).

1m+n)

For example, the above example m=n=30. If =j=30 is used, the number of calculations will be 5.4XlO', and the calculation time will be 5.
Since the time is 4 milliseconds, which is 1/15 of the conventional time, it can be seen that the target tracking performance in real time is significantly improved.

Note that since the addition operations in equations (2) to (5) can be executed in parallel with the pixel readout scan of one screen,
The increase in calculation time due to this can be almost ignored.

As described above, according to the present invention, the correlation calculation time can be significantly reduced, so that the target detection speed can be increased and the target tracking performance can be improved.

[Brief explanation of drawings]

Figure 1 shows the configuration of a conventional device, Figure 2 shows the relationship between the screen and the first and second gates, Figure 3 shows the correlation coefficient, and Figure 4 shows the invention. (1 of 2 configurations
A diagram showing an example; FIG. 5 is a diagram showing a data compression method;
FIG. 6 is a diagram showing an example of a method for storing compressed data in a memory. In the figure, +41. +51 is a gate circuit, and (8) is a correlation calculation circuit. (IG is a gate shift circuit, a2 is a correlation coefficient determination circuit. ao, □□□ are addition circuits, +211. (2) is a memory. In Figure 9, the same or equivalent parts are given the same reference numerals. Agent Masuo Oiwa Figure 1 □■ 1g2 Figure 3 Figure 4 fi5, (α) 1→i Figure 6 uu 2f ノ

Claims (1)

[Claims] The image cut out by the first gate surrounding the target is stored in the initial screen, and in the subsequent screen, the position of the image that most matches the image cut out by the first gate is determined. In a target position detection device that detects a target position by
A first storage means for adding the pixels of the image cut out by the first gate in the horizontal and vertical directions and storing the result of the addition in a predetermined order; and means for producing a second gate having the same dimensions as. The pixels of the image cut out by the second gate are horizontal. and a second storage means for vertically adding the two-way addition results and storing them in the order in which they were stored, and the degree of coincidence between the contents of the first storage means and the contents of the second storage means. and the gate installation position of $2 at a pitch that is an integral multiple of one pixel. Means for shifting horizontally or vertically. Among the degrees of coincidence calculated at each installation position of the second gate, the degree of coincidence is the highest. The present invention is characterized by comprising means for detecting the installation position of the second gate. Target position detection device.