JPH02151180A - Image pickup device - Google Patents

Abstract

PURPOSE:To prevent the reduction in the dynamic resolution caused by a blur of a hand or panning or the like at the pickup by detecting the movement of the entire pattern or the movement of a device main body at the pickup and controlling a shutter speed based on the result of detection. CONSTITUTION:An output of an AGC circuit 4 is inputted to a process circuit 5 and also to a panning detection circuit 8. A sensing signal for hand blur or panning or the like detected by the panning detection circuit 8 is inputted to a shutter speed control circuit 9. Upon the receipt of the sensing signal for hand blur or panning or the like, the shutter speed control circuit 9 switches the shutter speed to the fast mode such as 1/500sec. Then a pulse driving an electronic shutter function is outputted from a drive pulse generating circuit 7 to an image pickup element 2 by the signal from the control circuit 9. That is, if hand blur or panning or the like takes place, it is sensed automatically and the electronic shutter function is driven only at the sensing to improve the dynamic resolution.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a one-image device such as a video camera having one function of 5 electronics and 1v4 shutter.

[Conventional technology]

FIG. 5 is a block diagram showing the circuit configuration of a conventional imaging device having an electronically controlled shutter function, and here the case of a video camera is shown. In the figure, l is the lens for photographing the subject, and 2 is 11? through the lens 1. 3 is a solid-state image pickup device that converts the captured image into an electrical signal; 3 is an S/H circuit that samples and holds the signal 1 taken out from the 1-body image pickup device 2; 4 is a S/H circuit that samples and holds the sampled and held signal; AGC circuit that amplifies to the necessary level,
5 is a process (signal processing) circuit that processes the human input signal from the AGC circuit 4 and outputs a standard video signal, and 6 is an external changeover switch attached to the video camera body.
With this changeover switch 6, the shutter speed can be changed to, for example, 1/
It can be switched to 60 seconds, 11500 seconds, or 1/1000 seconds. Reference numeral 7 denotes a drive pulse generation circuit that generates a drive pulse according to the shutter speed selected by the changeover switch 6, and the image pickup device 2 is driven by the drive pulse.

In the video camera configured as described above, the solid-state image sensor 1 usually has an electric charge corresponding to one field (1/6 o seconds in the case of the NTSC system) in its light receiving section depending on the intensity of the incident light from the lens 1. ), and the charges are sequentially extracted as signals.

Then, this increased signal is transmitted to the S/H as described above.
It enters the process circuit 5 via the circuit 3 and the AGC circuit 4,
Necessary signal processing is performed here and the signal is output as a standard video signal.

At this time, when a fast-moving subject is photographed, the video flows, so the high frequency components included in the video signal decrease, resulting in a decrease in resolution and poor dynamic resolution. Therefore, the video camera is provided with an electronically controlled shutter function that releases the charges accumulated in the solid-state image sensor r2 at a certain zero timing and extracts only the charges accumulated during the remaining period. That is, when photographing a fast-moving subject, the photographer operates the external changeover switch 6 and selects the shutter speed according to the speed of the subject. Thereby, it is possible to suppress the reduction in the above-mentioned dynamic resolution.

In addition to the movement of the subject, the causes of the reduction in the dynamic resolution include blurring and vanning, which tend to occur when a photographer takes a picture of a subject with a handheld video camera. However, even in such a case, by activating the electronic shutter function described above, it is possible to prevent the dynamic resolution from decreasing.

(Problem to be Solved by the Invention) However, in the imaging device described in 1- above, the electronically controlled shutter function must be kept in operation at all times in order to prevent a decrease in dynamic resolution. Therefore, there was a problem that the low resolution of one image increased.In other words, camera shake and banging were different from when shooting fast-moving subjects.
This is difficult to measure, and therefore the electronically controlled shutter function must be kept in operation at all times, but at this time, a larger amount of incident light is required than during normal shooting, so smearing is likely to occur. 5. There is a problem in that the deterioration in image quality increases.

The present invention has been made to solve these problems, and provides an imaging device that prevents a decrease in dynamic resolution caused by camera shake or banging during shooting, and at the same time minimizes the decrease in image quality. It is intended to.

[Means to solve the problem]

The imaging device of the present invention is configured as follows.

(a) In an imaging device equipped with an electronically controlled shutter function, a detection means detects movement of the entire screen during image capturing, and a control means controls the shutter speed of the electronically controlled shutter function based on the detection result. Equipped with

(b) In an imaging device having an electronically controlled shutter function, a detection means for detecting movement of the main body of the apparatus during imaging, and a control means for controlling the shutter speed of the electronically controlled shutter function based on the detection result. Equipped with

(Function) In the imaging device of the present invention, by having the configuration described in item (a), when the entire screen moves during shooting, the movement is detected by the detection means, and based on the detection result, the
The shutter speed of the control shutter function is controlled.

Furthermore, by using the configuration (b), JM j, 12
When the main body of the device moves, that movement is detected, and the shutter speed is controlled based on the detection results. That is, the electronically controlled shutter function is activated only when necessary.

(Embodiment) FIG. 1 is a block diagram showing the circuit configuration of an imaging device according to an embodiment of the present invention. As in the conventional case, the case of a video camera is omitted, and the same reference numerals as in FIG. 5 indicate the same components. In the figure, 1 is a lens for photographing the subject, and 2 is a CCD.
3 is an S/) 1 circuit that samples and holds the signal read out from the 1^1 image sensor 2, 4 is an input signal from the S/H circuit 3, and No. 4 is brought to the required level. An AGC circuit for amplification, 5 a process circuit for generating a standard video signal of the imaged image, 7 a drive pulse generation circuit for outputting drive pulses to the solid-state image sensor 2, and 8 a control circuit for controlling the movement of the entire screen during image capture. A banning detection circuit provided as a detecting means detects banning, etc. including hand shake during imaging. Reference numeral 9 denotes a shutter speed control circuit, which is one stage of the control section, which controls the shutter speed of the electronically controlled shutter function based on the result of the test 11. The drive pulse generation circuit 7 performs imaging according to the output signal of the shutter speed control circuit 9. Generates drive pulses for driving elements.

Next, the operation of the video camera configured as described above will be explained.

As in the conventional case, the imaging light from the lens 1 is transmitted through the solid-state image sensor f-
The light enters the light receiving section 2, where it is converted into an electrical signal and sequentially read out. The signal read out from this image sensor 2 is
S/H circuit 3. The signal is inputted to the process circuit 5 through the AGC circuit 4, where it undergoes necessary (ri) processing and is output as a standard video signal.

Further, the output of the AGC circuit 4 is input to the process circuit 5 and also to the vanning detection circuit 8. This banging detection circuit 8 detects movement of the entire screen due to one shake, banging, etc. as described in L.
At this time, the movement of the screen is determined and detected separately from the movement of the subject.

FIG. 2 is a block diagram showing a specific example of the banning detection circuit 8. As shown in FIG. In the figure, 12 is a band pass filter (BP
F), 13 is a detection circuit, 14 is an A/D (analog/digital) converter, 15 is a low-pass filter (LPF)
, 16 sets the output of the low-pass filter 15 to a predetermined voltage value V
A comparator to compare with rer, 17 is a comparator! 18 is a comparator that compares the output of counter 17 with a predetermined value A, 19 is a register group consisting of a plurality of n-bit shift registers, 20
is an adder (FA) that adds the output of the register group 19 and the output of the comparator 18; 21 is a counter that counts the clock; 22 is a counter that counts horizontal drive pulses (HD); A comparator that compares the output with a certain value A2, 24 is the output of the comparator 23? The output of the comparator 23 is also input to a D-type flip-flop (D-FF) 25. 26 is a comparator that compares the output of the comparator 23 and the output of the memory 24; 27;
is a comparator that compares the output of the comparator 23 and the output of the flip-flop 25, 28 and 29 are counters, 30 is a logic control unit that performs a predetermined logical operation, and 31 is a D/A (digital/analog) converter. .

- In the banning detection circuit 8 having the configuration as shown in F, first, the video screen is divided into case f-shaped blocks of length m x width n as shown in FIG. The average value i- of the luminance level within the block is determined. Then, this value is compared with the average value A of the luminance level of the entire screen, and if, for example, a,<A, then b,=.

If ai, ≧A, then b, , = 1. For each block, binarized information 1) ij is obtained as information corresponding to the luminance level within that block. The obtained binary information b1J of each block is stored in the memory 24 of FIG. 2 as data b i for one field. Here, if the screen moves due to camera shake or banging, turn 4 of 1 screen Of (1 field fif).
1. The brightness level within the block changes every so often (f
) The mean values a and J also change, and 2f〆(value information b i,
+ also changes. At this time, the 1 stored in the memory 24 is
Binarization in front of the screen (one field before) Hb i,,+'
The comparator 26 detects the difference between and the binarized information b i in the current field, or the sum of the stiffness over the entire screen is s, = "x'x 1 b , J-b , .
' This value S1 is obtained by a counter 28 and changes depending on the field-to-field changes on both sides.

On the other hand, the D type flip-flop 25 holds data for one block in the horizontal direction, but the data of one block +) H obtained from this D type flip-flop 25 is compared with the data in the current block. 27, and the difference between the respective binarized information is detected. What is the sum of this for the entire screen?

52=1°shi1b+-Lj-b,.

This value S2 changes depending on the complexity of the entire screen. Then, the F planting S obtained in this way,
, S2 are manually operated by the logic control unit 30, and the following equation is calculated.

S=S, /52 - The obtained S represents the normalized amount of change in the screen, which is not affected by the complexity of the screen. Here, when the entire screen moves due to camera shake or banging, the above S changes by the amount of movement in the water/Y direction, regardless of the complexity of both sides, but the screen is fixed and occupies a part of the screen. If only the subject moves, the screen clutter value S2
The change value S of the binary conversion between fields shows a relatively small value, and the normalized (/l S) also has a small value. In other words, even with the same movement 11N, the screen changes due to one shake or banging. The value of S is different when the entire object moves and when only a part of the object within the screen moves, and this difference can be used to detect camera shake, banging, etc.

Detection signals such as camera shake and banging detected by the banging detection circuit 8 as described above are input to the shutter speed control circuit 9 manually. The shutter speed control circuit 9 switches the shutter speed to a fast mode of, for example, 11,500 seconds when a detection signal such as small puwa or banging is input manually. Then, in response to the signal from the control circuit 9, a pulse for driving the electronic shutter function is output from the drive pulse generation circuit 7 to the image sensor 7'-2. In other words,
When blurring or bunning occurs, it automatically detects this, and only when it fails to detect it, activates the electronic printing function to improve dynamic resolution. For this reason, low dynamic resolution is prevented from IL, and at the same time, deterioration in image quality is suppressed to a minimum.

In the above description, the shutter speed mode may be set in two stages, or may be switched to a plurality of stages depending on the output level of the panning detection circuit 8. Also,
The shutter speed can also be set to an appropriate value, 0.

FIG. 4 is a block diagram showing another embodiment of the present invention.

In the above embodiment, the panning detection circuit 8 that detects the movement of the entire image is used to detect camera shake and panning, but in this actual hh example, a speed sensor is used to detect the movement of the main body of the image sensor f. This allows detection of f-shake, banging, etc. That is, in FIG. 4, 10 is i for detecting the speed applied to the video camera body (Ihi image device body).
'T speed sensor 11 is an arithmetic circuit that calculates the speed level based on the detection signal from the speed sensor lO, and these constitute means for detecting movement of the video camera body caused by camera shake, banging, etc.

In the video camera having the above configuration, when the speed is applied to the video camera body due to bunning or the like, the speed increases as follows: Ii■ Speed sensor 10 and arithmetic circuit 1! The shutter speed is controlled so that the higher the applied irf speed is, the faster the shutter speed is.

At this time, the shutter speed control circuit 9 compares the output level of the iJ speed sensor 1o with a certain set level using a built-in comparator to control the shutter speed, but in this case, the shutter speed exceeds the set level. The shutter speed may be changed from the normal speed to a certain high speed when the shutter speed is changed, or the shutter speed may be changed steplessly according to the available speed.
It is possible to discriminate and detect the movement of the subject and the movement of the screen caused by camera shake, banging, etc., and the same effect as the embodiment described above can be obtained.

(Effects of the Invention) As described above, according to the present invention, the configuration is such that the movement of the entire screen or the movement of the device itself is detected during shooting, and the shutter measurement is controlled based on the detection result. Therefore, it is possible to prevent a decrease in dynamic resolution caused by camera shake, banging, etc. during photographing, and at the same time, it is possible to achieve the effect that a decrease in image quality can be minimized.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a circuit configuration of an imaging device according to an embodiment of the present invention, FIG. 2 is a block diagram showing a specific example of the panning detection circuit shown in FIG. 1, and FIG. 3 is a diagram showing how the video screen is divided. FIG. 4 is a block diagram showing another embodiment of the present invention, and FIG. 5 is a block diagram showing the circuit configuration of a conventional imaging device. 1... Lens 2... Solid-state image sensor 3... S/H circuit 4... AGC circuit 5... Process circuit 7... ... Drive pulse generation circuit 8 ... Panning detection circuit (detection means) 9 ...
...Shutter speed control circuit (1 stage control) 11...
...Existence 1st J lj, 7j 昂(Sequence #Lt-dan)

Claims (2)

[Claims] (1) An imaging device having an electronically controlled shutter function, comprising a detection means for detecting movement of the entire screen during image capturing, and a control means for controlling the shutter speed of the electronically controlled shutter function based on the detection result. An imaging device characterized by: (2) An imaging device having an electronically controlled shutter function, comprising: a detection means for detecting movement of the main body of the apparatus during imaging; and a control means for controlling the shutter speed of the electronically controlled shutter function based on the detection result. An imaging device characterized by: