JP2003018450A - Still picture imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a still picture imaging apparatus that can pick up a succeeding image in a shorter time than a usual time when the condition permits in picking up the image of an object consecutively for a short time. SOLUTION: The still picture image apparatus that picks up an object as a still picture by using an imaging device 2 is provided with a detection means 12 detecting that the object is moved or the device is moved, and setting means 51, 52, 53 that set an imaging condition by processing the signal read from the imaging device 2. The still picture imaging apparatus is characterized in that when the detection means 12 detects almost no motion until succeeding imaging after the preceding imaging, the image of the object is picked up according to the setting of the preceding image pickup without activating the setting means 51, 52, 53.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a still image pickup device, and more particularly to a still image pickup device capable of continuously picking up images in a short time.

[0002]

2. Description of the Related Art In recent years, the resolution of image pickup devices used in still image pickup devices such as digital still cameras has increased, and the amount of data required for signal processing has also increased. As a result, a higher performance signal processing IC is required, which contributes to increasing the cost of the device. On the other hand, when a signal processing IC having the same performance as the conventional one is used, the time required for signal processing becomes long. In this case, even if the user intends to continuously capture an image of the subject in a short time, the next image cannot be captured because the previously captured image is being processed in the device.
There was a risk of missing the so-called photo opportunity.

[0003]

SUMMARY OF THE INVENTION Therefore, the present invention provides a still image pickup device capable of picking up the next image in a shorter time than usual if the conditions are matched when the subject is continuously picked up in a short time. The task is to do.

[0004]

The invention according to claim 1 for solving the above-mentioned problems is a still image pickup device for picking up a subject as a still image by an image pickup device, wherein the subject or the device itself has moved. And a setting unit configured to set an image capturing condition by processing a signal read from the image sensor, and after the previous image capturing is performed until the next image capturing, the detecting unit When it is detected that there is almost no movement, the still image capturing apparatus is characterized in that in the next image capturing, the setting unit is not operated and the subject is imaged with the setting at the time of the previous image capturing.

According to a second aspect of the present invention, the detecting means is
The still image pickup device according to claim 1, wherein the still image pickup device is an acceleration sensor.

According to a third aspect of the present invention, the detecting means is
The still image capturing apparatus according to claim 1, wherein the processing is performed by processing a signal read from the image sensor.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 is a block diagram showing the internal structure of a still image pickup device according to the present invention. In the figure, 1 is an image pickup optical system, 2 is an image pickup element, 3 is a CDS / AGC / AD unit, 4 is a timing generator, 5 is a signal processing IC circuit, 6 is SDRAM, 7 is a system control circuit, and 8 is a shutter / iris. Driver, 9 is a focus driver, 1
Reference numeral 0 is a ROM, 11 is a CF card, and 12 is a motion vector detection circuit.

The image pickup optical system 1 includes an image pickup lens, a focus mechanism for driving the image pickup lens for focusing, and a diaphragm mechanism for adjusting the diaphragm. The image pickup device 2 captures an optical image from a subject (not shown). The image is formed on the imaging surface of. The image pickup device 2 is a solid-state image pickup device including a CCD (Charge Coupled Device) or the like, and photoelectrically converts the formed optical image into a signal charge according to the amount of light in pixel units.

The timing generator 4 generates various timing signals for driving the image pickup device 2, such as a read pulse, a vertical transfer pulse, a horizontal transfer pulse, and a shutter pulse. In the image pickup device 2, the signal charges obtained by photoelectric conversion for each pixel are read out to the vertical transfer unit by being given a read pulse from the timing generator 4, and further transferred to the horizontal transfer unit, and finally. It is output to the CDS / AGC / AD unit 3 as an electric signal.

In the CDS / AGC / AD unit 3, noise is reduced by performing CDS (correlated double sampling) processing on the electric signal output from the image pickup element 2, and by an AGC (automatic gain adjustment) circuit. The gain is adjusted, converted into a digital signal by the A / D converter, and output to the signal processing IC circuit 5.

The signal processing IC circuit 5 performs predetermined brightness processing and color processing on the input digital signal to generate an image signal converted into a brightness signal (Y) and a color difference signal (Cr, Cb), It is temporarily stored in the SDRAM 6.

The signal processing IC circuit 5 includes an AE (automatic exposure) processing unit 51, an AF (automatic focus adjustment) processing unit 52,
It has an AWB (auto white balance) processing unit 53, and performs these processes on an input digital signal.

The AE processing unit 51 calculates an AE evaluation value (photometric value) according to the brightness of the subject by performing an arithmetic process mainly including cumulative addition of digital signals for each pixel.
Based on this AE evaluation value, the system control circuit 7
Drive the shutter / iris driver 8 via
The exposure is controlled by drivingly controlling the diaphragm in the imaging optical system 1. Further, the image sensor 2 generally performs an electronic shutter operation in which the signal charge accumulated in the pixel is swept away by applying a shutter pulse, and photoelectrically converts the optical image in the period until the next reading to charge. Is accumulated. This accumulation period is the so-called shutter speed. Therefore, the AE processing unit 51 controls the shutter speed in the image sensor 2 and controls the exposure by controlling the generation timing of the shutter pulse in the timing generator 4 based on the AE evaluation value.

The AF processing unit 52 extracts, from a digital signal, a high frequency component of a pixel signal for one screen, for example, by a high pass filter, and performs a calculation process such as cumulative addition on the extracted high frequency component to obtain a high frequency range. The AF evaluation value corresponding to the side contour component amount is calculated, the focus driver 9 is driven via the system control circuit 7 based on the AF evaluation value, and the focus lens in the imaging optical system 1 is driven and controlled in the optical axis direction. Focusing is done by doing.

The AWB processing unit 53 receives the pixel signal,
For example, the signal processing IC circuit calculates a white balance adjustment coefficient so as to average the entire color information to obtain an achromatic color, and uses the adjustment coefficient to correctly reproduce white regardless of the color temperature of the subject. In 5, the generation of the image signal is controlled.

In the present invention, these AE processing units 5
1, the AF processing unit 52 and the AWB processing unit 53 constitute a setting unit that sets an imaging condition for imaging a subject. As will be described later in detail, in the release switches S1 and S2, which are configured in two stages as is well known, when the release switch S1 is pressed, the imaging conditions are set by performing these processes, and then the release switch S2. The main exposure is performed when is pressed.

In the present invention, the image pickup condition to be set may be any one or two of these, and in the present invention, the setting means may be any one that sets the image pickup condition. , But is not necessarily limited to the above.

In the EEPROM 10, the AE processing section 5 is provided.
1. Adjustment values and setting values for each processing in the AF processing unit 52, the AWB processing unit 53, and the like are stored. When setting conditions, optimum values can be set by calling these values in a timely manner. .

The generated image signal is recorded on the CF card 11 which is detachably attached to the apparatus main body.

The motion vector detection circuit 12 includes an image sensor 2
It is a detection unit that detects the amount of movement of the subject image by processing the image signal read from the signal processing IC circuit 5 and output from the signal processing IC circuit 5, and detects the presence or absence of the movement. Specifically, a one-frame image signal output from the signal processing IC circuit 5 and a delay unit (not shown) for the image signal.
The motion of the subject image is detected by comparing the image signals of two frames having a time difference with the image signal of one frame output via the. In this comparison, for example, a two-dimensional frequency is detected from the image signal and it is determined whether or not there is motion. The two-dimensional frequency may be detected in the entire screen or in divided blocks.

The movement of the subject image detected by the motion vector detection circuit 12 is relative, and it is possible to detect that the subject or the apparatus itself has moved. That is, even when the subject itself does not actually move, the movement of the image pickup device itself detects the movement of the subject image in the image signal captured from the image pickup element 2, and the case where the image pickup device itself does not move. Even if there is no movement in the image, there is a case where the movement of the subject itself in the image signal taken in from the image sensor 2 is detected by the movement of the subject itself. Then, in any of the above cases, it is judged from the detection of the movement amount that there is a movement.

In the present invention, the motion vector detection circuit 12 detects whether there is almost no motion. In the present invention, "there is almost no motion" means that the motion amount detected by the motion vector detection circuit 12 is smaller than a predetermined amount. Therefore, not only when there is no movement but also when the movement is detected by the motion vector detection circuit 12, if the movement amount is less than a predetermined value, "there is almost no movement". Other than that (when it exceeds the default value), it is determined to be “moving”. The default value of this amount of movement is the EEPROM
It is stored in 10.

Next, the control operation of the still image pickup device having such a configuration will be described with reference to the flow chart shown in FIG.

First, when the main power of the device is turned on (STEP
1) A predetermined initialization operation is performed by the system control circuit 7 (STEP 2). Next, it is determined whether or not the release switch is half-pressed by the user and the first-stage release switch S1 is turned on (ST
EP3). Here, if the release switch S1 is in the ON state, the system control circuit 7 energizes the image pickup element 2 to perform the setting process of the image pickup condition. That is, based on the image signal captured from the image sensor 2, the AE processing unit 51 performs AE processing (STEP 4), the AF processing unit 52 performs AF processing (STEP 5), and the AWB processing unit 53 performs AWB processing. By doing (STEP
6), setting of imaging conditions is executed.

Then, the user fully depresses the release switch to release the release switch S2 in the second stage.
Is turned on (STEP 7), and if it is ON, the main exposure is performed and the subject is imaged (STEP 7).
8) Then, the generated image signal is recorded (STEP 9).

If it is determined in STEP 7 that the second-stage release switch S2 is not turned on,
Subsequently, it is determined whether or not the release switch S1 is in the ON state (STEP 10). If the release switch S1 is in the ON state, the process returns to STEP 7 and the above processing is repeated. Also,
When it is determined that the release switch S1 is in the OFF state, it is determined whether or not the main power supply is in the ON state (STEP1
1).

If it is determined that the main power source is off, the system is terminated (STEP 12) and the power source is turned off (STEP 13).

On the other hand, when it is determined in STEP11 that the main power source is in the ON state, it is continuously determined whether or not the release switch S1 is in the ON state (STEP14). If the release switch S1 is in the OFF state, STEP11 Then, the above process is repeated.

Further, the release switch S1 is turned on here.
If it is determined to be in a state, it is determined whether a change in state has occurred. That is, the signal processing I from the image sensor 2
Based on the image signal taken into the C circuit 5, it is judged whether or not the subject or the apparatus itself has little movement (STEP 15). This determination is based on the motion vector detection circuit 12
It can be determined from the detection result of.

When it is determined that there is motion by the detection result of the motion vector detection circuit 12, it is determined that the relative position between the subject and the still image pickup device has changed, and the process returns to STEP 4 to change the setting of the image pickup condition. Perform processing to That is, based on the image signal captured from the image sensor 2, the AE processing unit 51 performs AE processing (STEP 4), the AF processing unit 52 performs AF processing (STEP 5), and further AWB.
By performing AWB processing in the processing unit 53 (STEP
6), the imaging conditions are set again, and thereafter, the same processing as above is repeated.

If it is determined in STEP 15 that the detection result of the motion vector detecting circuit 12 shows almost no movement, the relative position between the subject and the still image pickup device has not changed, and therefore the state of the subject is the same as before. There is almost no change from that at the time of imaging, and it is not necessary to change the imaging conditions. Therefore, A
The procedure proceeds to STEP 7 without re-setting the imaging conditions by the E processing unit 51, the AF processing unit 52, and the AWB processing unit 53,
Here, it is determined whether or not the release switch S2 is turned on. If the user continuously presses the release switch to turn on the release switch S2, the main exposure is performed in the same manner as above, and the subject is imaged (STEP
8) Then, the generated image signal is recorded (STEP 9). In this exposure, the imaging conditions are not reset and the AE process, AF process and A process in STEP 4 to STEP 6 are not performed.
Since the WB process is not executed, the subject is imaged in a shorter time.

As described above, in the present invention, after the release switch S1 is turned on, when the detection result of the motion vector detection circuit 12 is determined to have almost no motion, the AE processing unit 51 and the AF processing unit Since the main exposure is performed and the subject is imaged without setting the image capturing conditions by the 52 and the AWB processing unit 53, the next image capturing can be performed in a shorter time than usual.

In the above description, the motion vector detecting circuit 12 is used as the detecting means for detecting the movement of the subject or the apparatus itself, but the movement of the subject or the apparatus itself is detected. Instead of this motion vector detection circuit 12, as shown in FIG.
3 is provided as a detection means, and the system control circuit 7
In, the movement of the device itself may be detected based on the detection signal of the acceleration sensor 13.
Even by using the acceleration sensor 13, it is determined that "there is almost no movement" when the detected value is lower than the default value stored in the EEPROM 10, and when it is higher than the default value. By determining that there is "movement", the same control as above can be performed.

[0035]

According to the present invention, it is possible to provide a still image pickup device capable of picking up the next image in a shorter time than usual if the conditions are matched when the subject is continuously picked up in a short time. it can.

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing an embodiment of a still image capturing apparatus.

FIG. 2 is a flowchart showing a control operation of the still image pickup device.

FIG. 3 is a configuration block diagram showing another embodiment of a still image capturing apparatus.

[Explanation of symbols]

1: Shooting optical system 2: Image sensor 3: CDS / AGC / AD section 4: Timing generator 5: Signal processing IC circuit 6: SDRAM 7: System control circuit 8: Shutter and iris driver 9: Focus driver 10: EEPROM 11: CF card 12: Motion vector detection circuit 13: Accelerometer

Claims (3)

[Claims] 1. A still image pickup device for picking up a subject as a still image by an image pickup device, comprising: detecting means for detecting movement of the subject or the device itself; and processing a signal read from the image pickup device. When the detection unit detects that there is almost no movement after the previous image capturing until the next image capturing, the setting unit configured to set the image capturing condition is set in the next image capturing. A still image pickup device, which picks up an image of a subject with the setting at the time of the previous image pickup, without operating. 2. The still image pickup device according to claim 1, wherein the detection means is an acceleration sensor. 3. The still image pickup device according to claim 1, wherein the detection means performs the processing by processing a signal read from the image pickup element.