JPH02210974A - Still video camera - Google Patents

Abstract

PURPOSE:To make the size of a camera compact without requiring any exclusive photometry element by obtaining a photometry data to decide each pickup condition through the use of a pickup CCD. CONSTITUTION:The readout of a video signal and the pickup of a CCD 2 are implemented with a CPU 1 by using a control signal from a CCD drive circuit 3. An overflow detector 4 detects a charge flowing into an overflow drain of the CCD 2 to detect it that the stored charge in the CCD 2 overflows. The CPU 1 uses the detection signal to measure the overflow time after the storage of charge is started by the CCD 2 till the stored charge overflows, Then the proper charge storage time of the COD 2 is calculated based on the measured time at the calculation of each pickup condition such as automatic focal distance, automatic exposure or white balance. Then each photometry information is collected by using only the CCD 2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a distance measuring and photometric means for determining various photographing conditions such as AF, AE, and AWB in a still video camera using a solid-state image sensor.

[Prior Art] In conventional still video cameras, for example, distance measurement data for determining control conditions for autofocus (AF), automatic exposure control "a (AE)", auto white balance (AWB), etc. The photometric data for determining the shooting conditions is obtained using a dedicated light-receiving sensor.For example, in AE, a light-receiving sensor for monitoring is placed next to the solid-state image sensor (hereinafter referred to as COD) for shooting. Some cameras are equipped with a light receiving element for AEII light at a position equivalent to the film surface within the pentaprism to monitor the subject brightness. An AF sensor module is installed at the bottom of the camera body similar to the AF mechanism, or of two subject images to be compared, one image is captured with a COD for shooting, and the other is captured with an m-image using another imaging device. There is a method that does this (Jikoi No. 55-74270).

Furthermore, some movie video cameras are designed to also serve as a COD for photographing and to emit A2m light.

In addition, the output from the imaging solid-state ME element is read out in a focused state and in a slightly out-of-focus state, and a luminance signal is obtained from the output in the former state, and a chrominance signal is obtained from the output in the latter state. (Japanese Unexamined Patent Publication No. 62-173)
Publication No. 876).

(Issues to be solved and attempted to be solved by 'Ia') As described above, in conventional still video cameras, the photometric data for determining each shooting condition is collected using a dedicated photometric sensor, or a portion of the 'Ia image. Although the 1IiI COD may also be used, there is no example shown in which the photometric data is obtained using the 1IiI COD. If the camera is constructed so that photometric data for determining each photography condition can be obtained using only the COD for photography, the mechanical configuration of the camera can be made compact, and manufacturing cost advantages can also be achieved.

The present invention has been made in view of the above background, and an object of the present invention is to provide a still video camera that uses a solid-state imaging device for photographing to obtain photometric data for determining each photographing condition. .

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention provides a still video camera that uses a solid-state image sensor to take pictures, and includes means for measuring the time until the accumulated charge of the solid-state image sensor reaches a certain amount, and A means for calculating the charge accumulation time in the solid-state image sensor for distance measurement and each photometry from the obtained time, and a means for accumulating charge in the solid-state image sensor for each calculation time circle to set the AFillll1 condition and each shooting. and means for calculating conditions.

[Effect]

In the still video camera configured as described above, first, before photographing, charge is accumulated in the solid-state image pickup device for second grade, and the time until the accumulated charge reaches a certain amount is measured.

Next, when calculating 11Q8II shadow conditions such as AF distance measurement and AE and AWB, the appropriate charge accumulation time of the solid-state image sensor is calculated based on the measurement time, and the charge is stored in the solid-state image sensor for the calculated time. The distance measurement and photometry information necessary to calculate the distance measurement and each photographing condition are collected.

〔Example〕

FIG. 1 is a circuit diagram showing an embodiment of a still video camera according to the present invention. In the figure, a central control circuit 1 (under IX, referred to as CPU 1) is a microcomputer that controls the drive of each of the following actuators to intensively perform the photographing operation of the camera and the recording of images.

The silver image element 2 (hereinafter referred to as ccD2) is disposed at a position corresponding to the film surface of the camera, and is a CO
This is a solid-state image sensor such as D. In addition, as described later, CC
D2 has autofocus (AF) calculation, automatic exposure (AE)
) calculation and auto white balance (AWB) calculation.

During shooting, the video signal captured by C0D2 is input to the color separation circuit 16 via the switch SW1, and the eye color separation circuit 16 separates the signal components of each color of red (R), green (G), and blue (B). After being separated into two, each signal is input to the matrix circuit 17 via a switch SW4. Then, the matrix circuit 17 converts the RGB signal components into a luminance signal E y 1 color difference signal (ER-EY) and (EB-
EY) is generated, and these signals are recorded on the floppy disk of the recording section 18.

The C0D2 imaging and video signal readout operations are performed by the CPU.
1, the control signal from the CCD drive circuit 3 is used. The overflow detector 4 detects the amount of charge flowing into the overflow drain of the CCD 2 to detect that the accumulated charge of the C0D2 has overflowed. The cpui uses this detection signal to detect C0 as described later.
The time Tov (hereinafter referred to as overflow time) from when D2 starts accumulating charges until the accumulated charges overflow is measured.

The clock generator 5 is controlled by the control signal from CPtJl.
It generates a basic tarok signal with a pulse period synchronized with the signal readout timing of one pixel of 0D2. This basic clock signal is the CCD output from the CCD drive circuit 3.
It is generated in synchronization with the start of output of the horizontal control pulse of 0D2, and is stopped at the same time as the output ends. The basic clock signal is then input to the counter 6, and is used for the designated count value of the photometry area measured by the counter 6, as will be described later.

In this embodiment, in addition to photographing, the C0D2 is also used as a light receiving element to obtain photometric information necessary for AF calculation, measurement of the overflow time, AE calculation, AWB operation, etc. The switches sW1 to SW5 are used to switch the processing circuit for the video signal received by the CCD 2 in accordance with each of the above calculations.

The switch SW1 is switched by a control signal of CPtJl in accordance with each process such as AF calculation, AE calculation, AWB calculation, photographing and recording. That is, in AF calculation, switch SW1 is connected to the b terminal, and C0D2
The video signal from switch SW5 and switch SW3
The signal is input to the A/D converter 20 via the A/D converter 20. The A/DII converter 20 converts the input analog video signal into a digital signal and outputs it to CPtJl. Further, in the AE calculation, the switch SW1 is connected to the C terminal, and the video signal is inputted to the integrator 8.9 via the switch SW2. The video signals integrated by the integrators 8 and 9 are input to the A/D conversion I20 via the switch SW3, and after being A/D converted, are input to the CPU 1. ,・For shooting/recording, switch S
W1 is connected to the a terminal, and the video signal is sent to the color separation circuit 1.
Enter 6.

In the AWB calculation, the R color signal separated by the color separation circuit 16 is directly input to the integrator 10, and the G and B color signals are input to the integrators 8 and 9 via the switch SW2, respectively. After the signals 8 to 10 are integrated for a certain period of time, they are each input to the A/D converter 20 via the switch SW3, and after being A/D converted, the signals are input to the CPU.

On the other hand, in photographing and recording, as described above, the signal components of each color of RGB are input to the matrix circuit 17, and the luminance signal and color difference signal generated by the matrix circuit 17 are recorded on the floppy disk of the storage section 18. .

The switch SW2 is switched by a control signal from the CPU 1, and is connected to the C1 terminal and the C2 terminal in the AE calculation, and as described above, the video signal of C0D2 is connected to the integrator 8.
．． Go to 9. In the AWB calculation, the G and B signal components connected to the C1 and C2 terminals and separated by the color separation circuit 16 are respectively input to the integrator 8.9.

Switch SW3 is the same as switch SW1 and switch SW2.
Similarly, it is switched by a control signal from CPLll,
In AF operation, it is connected to the h terminal and the switch SW
The video signal output from 5 is input to the A/D converter 20. In addition, in the AE calculation, the integrated signals connected to the C terminal and the f terminal and output from the integrators 8 and 9 are input to the A/D converter 20, and in the AWB calculation, the C terminal and the f It is connected to the terminal and the C terminal, and inputs the integral signals output from the integrators 8 to 10 to the A/D converter 20, respectively.

The switch SW4 connects the color separation circuit 16 and the matrix circuit 1.
This is a switch for turning on/off the connection with 7. For example, in the AWB calculation described above, each color separated color signal is input to the integrators 8 to 10, so the color separation circuit 1
6 and the matrix circuit 17 are turned off.

The switch SW5 is connected to the switch circuit 7 in the AF operation.
The on/off operation is controlled by the control signal from C0.
The video signal is outputted to the A/D converter 20 only during the period when the pixel signal used for focus detection is outputted from D2.

The counter 6 counts the basic tarock pulses from the clock generator 5 or the horizontal control pulses from the COD drive circuit 3, and when the counted value reaches a predetermined value input from the CPU, outputs a switching control signal to the switch circuit 7. It is something to do.

The switch circuit 7 is a circuit that controls the on/off of the switch SW5 and the integration operations of the integrators 8 to 10 based on the switch control signal inputted from the counter 6, respectively, for a predetermined period of time.

The integrators 8 to 10 are controlled by the control signal from the switch circuit 7.
The video signal of D2 is integrated for a predetermined period of time.

The circuit block 11 is an optical system drive unit that controls the driving of optical system members such as a photographic lens, and the circuit block 12 is an LE
It consists of D or LCD, and the shooting mode, exposure control value,
This is a display device that displays information necessary for photography, such as the number of images to be taken and the charging status of the flash. Further, the circuit block 13 is a flash circuit including a booster circuit and a flash emission drive circuit, the circuit block 14 is a motor drive section consisting of an AF motor that drives a photographing lens, and a motor that drives a mirror, and a circuit block 15 is a flash circuit that includes a booster circuit and a flash emission drive circuit. This is a group of operation switches including a main switch, a release switch, a mode select switch, and other various data input switches for photographing. Further, the D/A converter 19 converts the white balance data outputted from the CPU to the matrix circuit 17 into analog.

Next, use CCD2 to perform AF calculation, AE calculation, and AW calculation.
A method for obtaining 11 degree information for B calculation will be explained.

FIGS. 2(a) to 2(d) are side sectional views showing an embodiment of the optical system of a still video camera according to the present invention. Same figure (
a) When shooting is not performed (hereinafter referred to as normal time), (
b) shows the configuration of the optical system during AF photometry, (C) shows the configuration of the optical system during AWB photometry, and (d) shows the configuration of the optical system during overflow time measurement, AE11 light, and exposure. In the same figure (a), lens A is a photographing lens that focuses the object image on the imaging surface of C0D2, and lens B focuses the image point of the object image on CCD2.
A lens for shifting the focus to the front of the imaging surface,
The low-pass filter C is an optical low-pass filter that cuts high frequency components of light. In addition, in the same figure (b), the optical system is an AF optical system, and in the same figure (C), the diffuser plate E diffuses the light so that the light is evenly incident on the imaging surface of the CCD 2. be.

FIG. 3 is a perspective view showing an example of the above-mentioned AF optical system, which is a basic AF optical system of a phase difference detection method consisting of a well-known condenser lens D1 and a separator lens D2 in an AF-eye reflex camera. It is. During AF photometry, the AF optical system and focusing lens B are inserted on the optical axis of the photographing lens A10 - bus filter C and C0D2 of the optical system at the time of shooting, and the AF optical system and C0D2 are used to adjust the AF sensor. It is designed to configure modules.

At this time, in the imaging area of C0D2, areas 2a and 2b of the imaging area are used as AF detection areas, as shown in the figure.

The focus shifting lens B is provided to shift the focus plane from the imaging plane of C0D2 to the equivalent imaging plane f' in front of the condenser lens c11, as described above.
As shown in FIG. 2(b), it is inserted between the photographing lens A and the low-pass filter C during AF photometry. In addition, this focusing lens B is inserted in order to prevent the CCD 2 from being burnt by sunlight even in normal times, as shown in Fig. 2 (a), and even when the lens is at the infinity focusing position, the C0D2 is The camera is designed to be out of focus on the imaging surface.

First, before performing AF calculation, AE calculation, and AWB calculation, the overflow time Tov of the CCD 2 is set under the brightness condition of the subject. This overflow time T□v
is set in order to accurately perform photometry for AF calculation, AE calculation, and AWB calculation within the dynamic range of C0D2.

Since the optical system is normally in a defocused state as shown in FIG. 2(a), in setting the overflow time Tov (hereinafter referred to as Tov setting), first, the focusing lens B is retracted from the optical path. The optical system is set as shown in FIG. 2(d), and after refreshing the CCD 2 and removing residual @ charges, exposure is performed until the accumulated charges overflow, and the time Tov is measured. Note that if the subject brightness is low and the time until overflow is extremely long, the exposure is stopped after a certain period of time to.

Next, a photometry method for AWB calculation will be explained.

First, the optical system driving section 11 is driven to move the optical system as shown in FIG.
After refreshing C0D2 to remove residual charges, it is exposed for the overflow time Tov. In addition, a diffuser plate E is inserted between the focusing lens B and the low-pass filter C of the optical system, and the C
Since the light amount on the entire imaging surface of CD2 is made equal, CCD2 will not overflow even if exposed until the overflow time Tov.When the exposure of CCD2 is completed, CPU1 sets switch SW1 to terminal a and switch SW
2 to the C1 terminal and C2 terminal, and switch SW4
Turn off. The video signal of the CCD 2 is separated into RGB signal components by a color separation circuit 16, and then each is sent to an integrator 8.
．． 9 and 10, and the integrator 8.9 and 10
(, is integrated during the horizontal readout period of the pixel signal of CD2.

The counter 6 integrates the horizontal read signal input from the CCD drive circuit 3 during the horizontal read period! ! 18.9 and 10
A switching control signal is output to the switch circuit 7 so that the integration is performed. When the integration of integrators 8.9 and 10 is completed, CPtJl sequentially switches the C terminal, f terminal, and Q terminal of switch SW3, and converts each integrated signal into an A/D converter.
The converter 20 converts the data into digital data and imports the data.

Next, a photometry method for AF calculation will be explained.

First, the optical system driving section 11 is driven to configure the optical system as shown in FIG. 2(b). Thereafter, C0D2 is refreshed to remove residual charges, and then exposed for the overflow time Tov. In addition, since the focus shift lens B is inserted into the optical system and the focus is shifted from the imaging surface of C0D2, the CCD2 will not go over 70- even if the exposure is made up to fllTov at the time of overflow. When the exposure ends at C0D2, the CPU1 switches the switch S.
After connecting W1 to the b terminal and connecting the switch SW3 to the h terminal, the accumulated charge is output to the A/D converter 20 via the switch SW5, and converted into a digital signal by the A/D converter 20. , and import it as AF calculation data. At this time, the on time of the switch SW5 is set to t by the switch circuit 7.
Of the video signals output from the CCD 2, only the output signals of a specific period are output to the A/D converter 20 via the switch SW3. That is, C0D2
In order to use the video signal of a specific area within the imaging area of , as photometric information for AF, by counting horizontal control pulses and turning on switch SW5 for a certain period of counting, the image signal from the image area of CCD 2 is used for AF. The photometric area (AF area) is specified and the video signal of C0D2 of the photometric area is taken into CPtJl. Therefore, the CPU 1 outputs a count value to the counter 6 to specify the AF area. The horizontal control pulses output from the CCD drive circuit 3 are counted at the same time as reading starts, and when the predetermined count value m has been counted, a count end signal is output to the switch circuit 7.

The switch circuit 7 turns on the switch SW5 in response to the count end signal. Thereafter, when the horizontal control pulse is counted once (for one horizontal scan), a count end signal is output to the switch circuit 7. switch circuit 7
turns off the switch SW5 in response to the count end signal.

Next, a photometry method for AE calculation will be explained.

First, the optical system driving section 11 is driven to move the optical system as shown in FIG.
d), and after refreshing the CCD 2 and removing residual charges, it is exposed for a period of 1E between the appropriate FRs for AE photometry. During AE photometry, the optical system is the same as when setting the overflow time Tov, so if the overflow time @Tov is taken as the photometry time, an overflow will occur, so the proper opening tE is the overflow time Tov.
It is set shorter and calculated using the following formula.

tx-Tov/n Here, n is a constant obtained in advance through experiments.

When the exposure of C0D2 is completed, CPIJl is switched to switch S.
Connect W1 to the C terminal, connect switch SW2 to the C1 terminal and C2 terminal, read out the video signal 9 from the CCD 2,
The video signal is integrated by integrators 8 and 9 to produce a luminance signal. Thereafter, the cpui switches the C terminal and the f terminal of the switch SW3 to digitally convert the integral signals of the integrals a8 and 9 using the A/D converter 20, respectively, and capture them.

In the AE calculation of this embodiment, the exposure control value is calculated using a spot photometry value obtained by spot-metering the center of the shooting screen and an average photometry value obtained by averaging the photometry around the periphery of the shooting screen. , 11111ta of C0D2 is divided into a spot photometry area and an average photometry area, and the video signals of each photometry area are integrated for a predetermined time by the integrators 8 and 9, respectively, to obtain luminance information of each photometry area. There is a need.

Therefore, the iw1 specified count value for dividing the photometric area from the ms area of C0D2 and integrating the video signal of each area for a predetermined time is sent from the CPU 1 to the counter 6.
is input.

First, the counter 6 outputs a switching control signal to the switch circuit 7 at the same time that the horizontal control pulse from the COD drive circuit 3 is input, and counts the horizontal control pulse.

The switch circuit 7 outputs a signal for starting the integration of the integrator 8 in response to the switching control signal, and causes the video signal outputted from the CCD 2 to be integrated (integration of the brightness of the average photometry area). When the count number of horizontal control pulses reaches nl, counting of the basic clock signal from the clock generator 5 is started. Basic clock signal count number 1
When the counter 6 outputs a switching control signal to the switch circuit 7, the switch circuit 7 outputs an integration stop signal and an integration start signal to the integrator 8 and the integrator 9, respectively. As a result, the integrator 8 stops the integration, and the integrator 9 integrates the video signal output from the C0D2 (integration of the brightness of the spot photometry area). Furthermore, when the pulse count reaches 2, the counter 6 outputs a switching tjl1m signal to the switch circuit 7, and the switch circuit 7 outputs an integration start signal and an integration stop signal to the integrator 8 and integrator 9, respectively. . As a result, the integrator 9 stops the integration, and the integrator 8 again integrates the video signal output from the C0D2 (integration of the luminance of the average photometry area).

When the input of the basic clock signal is stopped, the counter 6 outputs a switching control signal to the switch circuit 7, and the switch circuit 7 outputs an integration stop signal to the integrator 8, so that the integration of the integrator 8 is stopped. The above operation is performed until the count number of horizontal control pulses is n1 to n2.

Next, when the count number of horizontal control pulses reaches 02, the same operation as described above when the count number of horizontal control pulses is from 1 to n1 is performed (integration of the luminance of the average photometry area).

As mentioned above, in AE photometry, the pulse period of the basic clock signal is synchronized with the readout period of the C0D2 pixel signal, so the number of readout pixel signals is counted and a separate integrator is used for each area specified count. By integrating the imaging signal output from the CCD 2, the photometry area of the imaging screen is divided to obtain a spot photometry value and an average photometry value.

FIGS. 4(a) and 4(b) show time charts of the above-mentioned AE photometry operation. In the figure, the horizontal control pulse is “Hiaf” for one line of the C0D2 video signal input from the COD drive circuit 3 to the clock generator 5.
The basic tarok signal is generated periodically during the generation period of the horizontal control pulse, and the pulse period is equal to the signal reading period of one pixel read out from the CCD 2. is equal to

Further, when the P1 output of the switch circuit 7 is l-1-1i, the integrator 8 performs an integrating operation, and when the P2 output is High, the integrator 9 performs an integrating operation (in other words, Pl is high
In the +ah state, the output of C0D2 is input to the integrator 8, and input to the integrator 9 is blocked. And P2 is H
In the high state, the output of C0D2 is input to the integrator 9, and the input to the integrator 8 is blocked). Therefore, in the case of FIG. 4(a), the pixel signal read out in the period of one horizontal control pulse is such that Pl is Htg in the period of horizontal control pulses 1 to n1 and n2 to n3.
h, so it is integrated by the integrator 8, and in the case of FIG. 4(b), the integrator 8 is integrated in the periods ■ and
are divided and integrated respectively. FIG. 5 is a front view of the CCD 2, where the hatched area is the spot photometry area (the area integrated by the integrator 9), and the other area is the average photometry area (the area integrated by the integrator 8). ).

Next, FIGS. 6(a) to 6(C) show a second embodiment of the optical system. In this figure, the same members as in FIGS. 2(a) to 2(d) are given the same reference numerals. Also, lens F
is a diffuser lens, and mirror G is a total reflection mirror. Under normal conditions, the optical system is in the state (a), and the diffuser lens F
The diffused light is totally reflected by the mirror G, passes through the low-pass filter C, and enters the CCD 2.

The light incident on the CCD 2 is diffused by a diffuser plate lens F to prevent the C0D 2 from being burnt by sunlight. Further, photometry for AWB calculation is also performed using the optical system configuration shown in (a), and this embodiment differs from the first embodiment in that it uses external light that is different from the subject light.

For photometry in AF calculation, use the optical system in (a) to retract the low-pass filter C from the optical path of the subject light, raise the mirror G, and
This is done with the configuration shown in (b) in which the F optical system is inserted in front of the imaging surface of the CCD 2. Further, Tov measurement, photometry for AE calculation, and exposure are performed with the configuration shown in (C). The focal length changes with the low-pass filter C, and when the O-bus filter C is set in the optical path of the subject light, the focus is on the CCD2.
When the low-pass filter C is retracted from the optical path of the subject light, the focus is on the AF
It is made to match the equivalent plane f' of the optical system.

Moreover, FIGS. 7(a) to 7(C) show a third embodiment of the optical system. The figure (a) shows the normal time. Even if the photographing lens A is adjusted to the infinite position when not photographing, it is kept out of focus on the imaging surface of C0D2 in order to prevent C0D2 from being burnt by sunlight as described above.

(b) shows the configuration at the time of AFfi light, in which an AF optical system is inserted at the focal position in the configuration of (a). (
C) shows the configuration at the time of Tov measurement, photometry and exposure of AE calculation, and in the configuration of (a), taking lens A and C0
A low-pass filter C is inserted between the filter and D2. As mentioned above, since the focal length changes due to the low-pass filter C, the W/iI! of CCD2! A low-pass filter C is inserted at a position where the plane is in focus.

Next, the shooting ffi of the still video camera according to the present invention is
[Explain the J sequence. First, the main routine will be explained using the flowchart shown in FIG.

CPU 1 starts operating upon power-on clear or reset (#0). When the CPU 1 starts operating, it clears the RAM area and each flag, performs initial settings such as setting the lens optical system to the state shown in FIG. 2(a) (normal state) (#i), and changes the state of the main switch So. Check (#2). If the switch So is OFF, no photographing operation is performed, so if #16 jumps and the flash circuit 13 is boosting the voltage, the boosting is stopped. Subsequently, all switches in the operation switch group 15 except switch So are set to O.
Check whether it is in the OFF state (#17), and if it is not in the OFF state, return to #2. If it is in the OFF state, the CPL
ll enters the HALT state (#18), and when any switch in the operation switch group 15 is operated and a change occurs in the switch, the CPU 1 is taken out of the HALT state,
Return to #2 (#19), HALT state is a low consumption state in which the CPU 1 returns to the normal state at regular intervals and returns to the normal state when it moves to #19 or when there is a switch interrupt. .

If the switch So is ON in #2, it is determined whether the switch So is switched from OFF to ON for the first time (#3). If it is turned ON for the first time, it is necessary to boost the voltage of the flash circuit 13. Set the boost flag indicating this (#4), and move the photographing lens A to the initial position (#5). In the AF calculation of this embodiment, the amount of focus deviation from the current lens position is calculated, and the taking lens A is driven by the amount of deviation to focus, so information on the distance to the subject is not required. Since the AE calculation requires information on the distance to the object, the position of the photographing lens A is initialized, and the CPU calculates the distance to the object based on the amount of movement of the photographing lens from the initial position. #
If the switch So of No. 2 continues to be in the ON state, the above #
4. Since #5 has already been executed, jump to #6. Next, check the condition of the deck lid (#11), and if it is open, reset the boost flag so that no picture will be taken or stop boosting the flash circuit 13 to save power (#11), and jump to #9. do. If the deck lid is closed, check whether the switch S1 is ONL (#7). If it is OFF, move to #9. If it is ON, check whether it is still in the ON state or not. ON
It is determined whether the switch has been made (#8). switch S
If the switch S1 has now been switched from OFF to ON, the process moves to the "S1 routine" to be described later, and if the switch S1 continues to be in the ON state, the process moves to #9. This determination in #8 is to prevent photographing from being performed one after another while the switch S1 is kept pressed.

In #9, the state of the mode changeover switch is checked, and if it is ON, it is determined whether the mode changeover switch continues to be in the ON state (#10). mode selector switch O
If the N state does not continue (when it is switched to ON now), the modes such as single-frame shooting, continuous shooting, and self-timer shooting are switched [mode switching routine] (not shown)
Move to.

If the mode selector switch is OFF or continues to be ON, check whether the boost flag is set (#12>. If the boost flag is not set, proceed to #16. Perform the processing from #16 onwards. If the boost flag is set, determine whether charging is complete (#13); if completed, #
Move to 16. If charging is not completed, boosting is started and a boosting timer is started. Then, check whether the boost timer has timed out, that is, whether the boost has been completed (#15). If it has timed out, proceed to the "rB-C routine" (not shown), perform a battery check, and check if the time has expired. If not, return to #2.

Next, the "S1 routine" will be explained using FIG. In the S1 routine, AF, A
E, AWB is performed to prepare for shooting.

When entering the 81 routine from the main routine, first, if the voltage is being increased, the voltage increasing operation is stopped (#20). Next, it is checked whether the release mode is not the self-timer mode (#21).

If it is not the self-timer mode, the spindle motor that rotates the floppy disk of the recording section 18 is turned on.

In self-timer mode, the spindle motor is not driven until just before the release, so the process moves to #23 without turning on the spindle motor to save power.
In steps 23 to #26, set the Tov and AW described above, respectively.
Performs B calculation, AF calculation and operation, and AE calculation. Then, when the AE calculation in #26 is completed, the white balance (WB) data (D/A
(converted into analog by the converter 19) to the 7-trix circuit 17 (#27), connect the switch SW1 to the a terminal, and turn on the switch SW4 (928). continue,
Check whether the boost flag is set in the AE calculation in #26 (#29). If the boost flag is set, monitor the voltage of the main capacitor of the flash circuit 13 and check whether charging has been completed. confirm(
#31) If the boost flag is not set or charging is completed, the process moves to #3o and switch S2
Check the status. If charging is not completed in #31, step-up is performed in #32 to #37, and the spindle motor is turned off.
If it is NL, turn it off (#32) and start boosting the voltage (#33). When charging is completed, stop boosting and return to #2 (#38). The reason why the spindle motor is stopped in step #32 is to save power by boosting the voltage, and since the release operation does not start unless the switch S1 is turned off once the voltage increases, there is no need to drive the spindle motor. #3, 4 to #37 determine whether there are any changes in the deck lid, switch So, and switch S1 during the charging period, and each time the deck lid is opened or the switches So and Sl are turned off during the charging period, the first This flow returns to #2 to execute the main flow.

If switch S2 is OFF in #30, #39 to #4
1, and until the switch S2 is turned on (until the release operation starts), it is determined whether there are any changes in the deck lid, switch So, and switch S1. , when the switches So and Sl are turned off, the process returns to #2 so that the main flow is executed from the beginning. If switch S2 is ON, check whether the release is not in self-timer mode (#42), and if it is in self-timer mode, LE
Execute the "self routine" (not shown) that counts a predetermined time while flashing D etc. (#43), turn the spindle motor ONL (#44), and run the "S2 routine" (
(described later) is executed (#45). If the release is not in self-timer mode, #43 and #44 are skipped and the "S2 routine" is executed. Execute the "S2 routine" and after the release is finished, check if it is not in continuous shooting mode (#46), and if it is in continuous shooting mode, repeat #23~
Execute #45 and perform the release operation. If it is not continuous shooting mode, turn off the spindle motor (#47), and if the release mode is self-timer mode or continuous shooting mode, set it to single mode (#48 to #4).
9). Then, set the focusing lens B and bring the optical system to the state shown in FIG. 2(a)), set the boost flag, and return to main routine #2 (#50.
#51).

Next, the Tov setting routine in #23 will be explained using FIG.

First, the optical system driving section 11 is driven to retract the focusing lens B, and the optical system is changed to a Tovfull fixed moon optical system (the optical system shown in FIG. 2(d) is established) (#101).

Next, the residual charge of C0D2 is removed and initialization is performed (
#102), C0D2 exposure is started (#103).

Further, at the same time as the exposure of C0D2 is started, the timer 1 (iov) built in the CPIJl starts counting up (#104), and sets the time tO in the timer 2 and starts counting down (#105). Note that the time to is a time limit for when it takes a long time for C0D2 to overflow due to low brightness or the like. continue,
When an overflow of C0D2 is detected (#106),
Stops the count up of timer 1 (tov) and returns C0.
Stop the exposure of D2 (#108.#109). In addition,
If C0D2 does not overflow even when timer 2 counts down to O (YES in #107), stop counting up of timer 1 (tov) at that point,
Exposure of C0D2 is stopped (#108.#109). Then, the count time of timer 1 (jov) is stored in the memory in the RAM as the overflow time Tov, and S
Return to 1 routine.

Next, the AWB calculation routine of #24 will be explained with reference to FIG.

First, drive the optical system drive unit 11, set the focusing lens B and the diffuser plate E, and create an optical system for AWBmIi (create the optical system as shown in FIG. 2 (C)) (#201>. Continued Then, initialize C0D2 (#202) and start timer 2.
Overflow time Tov set in #110 for (t)
(#203>, and start exposure of CCD2 (#204). At the same time as the start of exposure of C0D2, timer 2 (
t), and when it reaches t-0, stop the exposure of C0D2 (#2゜6, #205).
207), then the switch SW1 is connected to the a terminal, the switch SW2 is connected to the dl and d2 terminals, and the switch SW
Turn off integrator 8.4 (#208 to #210).
Integration of each color signal component of R9G and B by 9 and 10 is started (#211). When the integration is finished, switch SW
3 is connected to the ewA child, and the integral signal of G is A/D converted and taken into the CPU 1 (#212 to #216). Next, it is connected to the f terminal of switch SW3, A/D converts the integrated signal of B, and takes it into CPU1 (#217 to #
220), switch SW3 is connected to the q terminal, A/D converts the integral signal of R, and inputs it into CPU1 (#22
1 to #224). Then, CPtJl is the R, G, B
AWB calculation is performed based on the data of each integral signal (#22
5), return to S1 routine.

Next, the AF screen #25 will be explained using FIG. 12.

First, the optical system drive unit 11 is driven to retract the diffuser plate E, and the AF optical system is inserted to create an optical system for AF calculation (
(#301), then,
Set the counter (COtJNT) built in CPLJ 1 to O (#302).

In this embodiment, in order to achieve reliable focusing, the focusing operation is performed again after the focus determination, and the focus determination is confirmed twice. The counter (COLINT) counts the number of times. Therefore, the counter (COUN) is displayed at the beginning of the AF screen.
Reset the value of T), C0D21)] period,
(#303), set the overflow time Tov set in #110 to timer 2 (t) (#304)
, C0D2 is started (#305). At the same time as the exposure of C0D2 starts, the timer 2 (t) starts counting down (#306), and when it reaches t-0, the exposure of CCD2 is stopped (#307, #308).Subsequently, switch SW1 is set to b The switch SW3 is connected to the h terminal (#309.#310), and the counter 6 is connected to the above-mentioned AF
Input the specified count value for the I-area finger window (#311). Subsequently, the switch circuit 7 changes the 0N10FF operation of the switch SW5 to 1i1 according to the switching control signal from the counter 6.
1, the AF area video signal of C0D2 is output to the A/D converter, and the CPU takes in the digitally converted AF area video signal as AF data (#312 to #
315). The CPU 1 performs AF calculation based on the AF data (#316) and calculates the defocus amount OF (#3
17). Next, it is determined whether the camera is in focus based on the defocus ID F (9318), and if it is not in focus, the process moves to #319 and a focusing operation is performed. Note that in the focus determination, if the defocus IDF is less than or equal to a predetermined value, it is determined that the image is in focus. The focusing operation is performed using the defocus amount D.
Convert F to the number of driving pulses ND for the photographing lens, and (#31
9) After driving the photographing lens A until the number of drive pulses Nφ reaches the number of pulses ND (#320 to #322),
Returning again to the flow from #304 to #318, the AF calculation is performed, and the operation of determining focus after driving the photographic lens is repeated.

When it is determined that the focus is in focus in #318, the counter (COUNT
) should be added to #323), and if the value is not 2, then
Returning to #304, the focusing operation is performed again (#324), and the value of the counter (CoUNT) becomes 2. When this happens, the movement 1 of the photographing lens A at the time of focusing (the number of pulses from the start of lens drive to the stop of drive) is calculated (#325). The CPU 1 calculates the amount of movement from the initial lens position, calculates the object distance from the amount of movement of the lens A (#326), displays focus by lighting an LED (#327), and returns to #2 of the main routine. do.

Next, the AE screen will be explained using FIG. 13.

First, the optical system drive section 11 is driven to retract the focusing lens B1, the diffuser plate E, and the AF optical system to create an AE optical system (the optical system shown in FIG. 2(d)). 4
01). Next, initialize CGD 2 (#402),
Set the appropriate time j=Tov/n for AE photometry in timer 2 (t) (#403) and start exposure of C0D2 (
#404). Simultaneously with the start of exposure of C0D2, timer 2 (t
), and when it reaches t-0, stop the exposure of C0D2 (#406, #4
07). Next, switch SW1 is connected to the C terminal, and switch SW2 is connected to the 01 and C7 terminals (#408.#4
09), a count value specifying the average photometry tR area and the spot photometry area is set in the counter 6 (#410).

Subsequently, the pixel signal output from the CCD 2 is divided into a spot photometry area and an average photometry area by switching control of the switch circuit 7, and integrated by the integrators 8 and 9, respectively (#411). After the integration of integrators 8 and 9 is completed (YES in #412), switch SW3 is connected to the C terminal (#413), and the integrated signal of the average photometry area is converted to A/D.
Convert and import the average photometric data into CPU 1 (#
414-#416).

Subsequently, switch SW3 is connected to the f terminal (#417
), A/D converts the integral signal of the spot photometry area and imports the spot photometry data into CPIJl (#418~
#420). In CPLJl, the AE calculation described later is performed based on the average photometry data and spot photometry data (
#421 (#500)), shutter speed Tv and flash firing start time TVF if flash is required.
is determined (#422), and the process returns to the main routine (#423).

Next, the AE calculation in #421 will be explained using the flowchart of FIG. 14.

First, the average brightness BV2 and the center brightness Bvt are calculated from the average photometric data, the spot photometric data, and the integration time t (#501 and #502). In addition, A.E.
In operations, variable values shown in uppercase letters are apex values. Next, calculate the brightness difference Δ3v (=Bv2 Bvl) by taking the difference between the average brightness BV2 and the center brightness Bv1 (#503), and subtract the correction value α from the center brightness 8vt to find the main subject brightness Bvs (=Bv1- α) (#5
04). Note that the correction value α is stored in advance in the CPUI, and a predetermined value is determined based on the distance Dv to the subject and the brightness difference ΔBv.

Next, the average brightness BV2 is used as the sub-subject brightness Bv^
Set the standard value δ for backlight judgment from the main subject brightness 8vs (#506). The semi-value δ is also stored in the CPU 1 in advance, and the main subject brightness Bvs
A predetermined value is determined by Next, the brightness difference Δ3vl between the main subject brightness Bvs and the sub-subject brightness BVA
(=BvA-Bvs) and the reference value δ are compared to determine whether it is backlit or frontlit (#507), ΔBV' ≦δ
If so, it is determined that the subject is in front light, and the weighted average of the main subject brightness Bvs and the sub-subject brightness BVA is taken as the main subject brightness Bvs of the AE calculation in front light (#509). Note that the main subject brightness Bvs' is calculated by the following equation.

Bvs =<Bvs+7 ・8v ^)
/8Δ3 v l > 6, it is determined that the subject is backlit and the main subject brightness Bvs is set to AE during backlighting? The main subject degree of tll11 is set to Bvs'(65.10').

In the case of front light determination, the main subject brightness Bvs' is compared with the camera shake limit brightness BVH to determine whether the exposure control mode is natural light mode or dark flash mode (#509
), natural light mode is a mode in which exposure is controlled using natural light without using a flash. Further, the dark flash mode is a mode in which the brightness of the subject is dark, so the amount of light is supplemented with flash light, and the exposure side is performed. BVS'>B
If it is VH, it is determined that it is natural light mode, and the main subject brightness is 8.
vs, control shutter speed Tv from C0D2's 180 sensitivity Sv and open aperture value Avo (#5
12). Note that the control shutter speed Tv is calculated using the following equation.

Tv=Bvs +5v-Av.

Next, compare the control shutter speed Tv and the maximum shutter speed TVM (6513), Tv≧TVM.
If so, the TVM is set as the control shutter speed Tv (#514). Here, the maximum shutter speed TVM is the maximum shutter speed in the shutter function of C0D2.

#514 sets the control shutter speed Tv to the maximum shutter speed Tvm when the calculated value of the shutter speed exceeds the maximum shutter speed IIJ! ! It is something to do. Next, convert the set control shutter speed Tv to the actual shutter speed iv [seconds] (#515), reset the flash necessity flag, and #
422 (#516.#546). Note that the shutter speed jv is calculated by the following formula, and below,
Shutter speeds converted to seconds are expressed in lowercase letters.

tv, 2-Tv In the exposure control mode determination of #509, Bvs<BV)!
If so, it is determined that it is the dark flash mode, the shutter speed TVH at the camera shake limit is set to the ill all shutter speed Tv, and the control shutter speed tv is calculated from the control shutter speed Tv (#517). Next, flash guide number IvSISO sensitivity S
Aperture controlled by v and distance to subject III D v! IAv is calculated (1518). In this example,
Flash t with the so-called flashmatic method! II
The 1ilJ 1111 aperture value Av in the case of 1ilJ 1111 is calculated using the following formula.

Av-1v+5v-Dv ""■ Next, compare the control aperture value Av and the open aperture value Avo #519), and if Avo≦Av, the control aperture value A
Difference ΔAv between v and open aperture value Avo (=Av−Avo
) is calculated, and the necessary flash emission time tp (i.e., flash light amount) is calculated from the ΔAv (
#520. #521). The shorter the distance Dv from the subject, the larger the control aperture value Av calculated from equation (2).

Furthermore, if the subject is close, the amount of light from the flash may be small, so the larger the ill III aperture value Av, the shorter the flash emission time ty. Next, #5
III m shutter speed tv calculated in step 17 and the flash emission time 1. Calculate the flash emission control time tvp (-tv-ty) by taking the difference between
523), set the flush required flag and #42
Return to step 2 (#545.#546).

In #519, if Avo > Av, the subject is far away (,
Since it is determined that the amount of light from the flash is not sufficient to reach the subject, the total flash firing time tyo is set to the flash firing time 1 so that the flash fires fully within the time of M It shutter speed jv calculated in #517. ．． Toshiki #522), Etvro and the III i at the time of the light emission
Calculate the flash emission control time tvp (-iv-ty) from the LD shutter speed tv #523),
The flashing necessary flag is set and the process returns to #422 (#545.#546).

Next, in the case of backlight determination in #507, the sub-subject brightness BVA
The value obtained by subtracting 1 from the camera shake limit brightness BVH is compared to determine whether the backlight is bright or dark (#5
11). (BVA-1) If <BVH, it is determined that there is dark backlight, and the process moves to #517 above to perform AE calculation processing for dark flash mode. (BVA-1>≧BVH, it is determined that there is bright backlight. , the process moves to #524, and AE calculation processing for the backlight flash mode, which will be explained below, is performed.

In the backlight flash mode, in order to overexpose the secondary subject by 1 EV, the control i brightness value BVT is set to a value obtained by subtracting IEV from the secondary subject brightness (#524).

Next, the main subject brightness Bvs and the ti11wJ brightness value B
Find the difference in VT and calculate the exposure compensation value ΔEVN (-BVB-
BVT) (#525). This exposure compensation value ΔEVN
For example, when exposure is controlled using only natural light based on the exposure compensation value BVT, the exposure amount of the main subject falls short of the appropriate exposure amount, and the amount of light corresponding to this exposure compensation value ΔEVN is corrected with the flash. This allows the main subject to be properly exposed. Next, it is determined whether the exposure correction value ΔEVN exceeds -IEV (#526), Δ
If EVN > -1, the exposure compensation value ΔEVN is fixed at -1 (#527). This means that the exposure compensation value ΔEVN will be a negative value due to backlight conditions, etc., but if it is greater than -1, the calculation will be simplified. In order to do this, ΔEVN is fixed to -1. Next, it is determined whether the exposure correction value ΔEVN is less than 13EV (#528), and if ΔEVN≦-3, the correction value is 7f! : Set to 0 #530), ΔEVN>-3
If so, calculate the correction value K using the following formula (#529)
.

K--(ΔE V N + 3) / 2--■The correction value is the correction value ΔE of the flash guide number 1v.
It is used as VFL and is a correction value for the amount of flash light emitted. If 8EVN≦-3, the brightness difference between the main subject and the sub-subject is large and overexposure will not occur even if the flash is fired at full capacity, so the flash output amount is not corrected, and when ΔEVN>-3 Next, the guide number 1v is corrected using the correction value calculated using the simple calculation formula (2), and the amount of light emitted by the flash is corrected.

Next, set the correction value ΔEVFL to the correction value K #53
1) The guide number Iv is corrected by subtracting the correction value ΔEvpt from the guide number 1v (#532). In other words, the corrected guide number! ■ is expressed by the following formula.

Iv'-Iv-ΔEVFL ・・・・・・■ΔEVF
L is a value from O to -1, and the closer it is to -1, the smaller the brightness difference between the main subject and the sub-subject, so from formula Number Iv becomes larger.

The above-mentioned steps #524 to #532 perform correction based on the luminance difference of the subject, and the closer ΔEVFL is to −1, the more the amount of light emitted by the flash is reduced. Subsequently, in the following step, the flash light emission start time tF is set in consideration of the distance to the subject and correction based on the luminance difference of the subject.

Following #532, the corrected guide number Iv'
ISO sensitivity Sensitivity S increases from distance Dv to subject l1l
The aperture value Av is calculated (#533).

Note that Av is calculated by the following formula.

Av=Iv' +5v-Dv Next, the shutter speed Tv is controlled by the following formula from the control@brightness value BVT, ISO sensitivity Sv and open aperture value Avo.
is calculated (#534).

Tv-BvT+5v-Av.

Next, it is determined whether the control shutter speed Tv is between the maximum shutter speed TVM and the camera shake limit shutter speed TVH (#535° #536), Tv
If ≧TVM, then tlIJw? ”/Taspeed Tv
The maximum shutter speed is TvM (#537), Tv
If ≦TVH, the control shutter speed Tv is set to the camera shake limit shutter speed TVH (#538). Then, the calculated control shutter speed Tv is calculated from the formula 0, t
Convert to v (#539).

Next, compare the control aperture value Av calculated in #533 with the open aperture value Avo (#540). If Avo>Av, the subject is considered to be far away, so when the flash is fully emitted, rllll i FO when the flash fires! tF and #541'), then move to #549. If Avo≦Av, calculate the difference ΔAv (=Av−Avo) between the I control aperture value Av and the open aperture value Avo (#542), and calculate the required flash emission time 1. is calculated (#543). Next, #539
The shutter speed tv calculated in 1. and the light emission time 1. Take the difference between the flash and the xi time fl! 1tvy
Calculate (=tv - tp) #544), set the flush required flag, and return to #422 (#
545, #546).

FIGS. 15(a) to 15(d) are diagrams showing an example of the timing at which the flash described above starts emitting light.

FIG. 5A shows a case where the subject is far away and the flash is set to emit all the light within the controlled shutter speed jv. Figures (b) and (c) show cases in which the subject is relatively close and the subject is very close in dark flash mode, respectively.The closer the subject is, the more the flash starts firing just before the end of the COD exposure. I come to do it. FIG. 4(d) shows the start timing of flash emission in the backlight flash mode. Since the backlight flash mode is bright backlight, exposure is controlled so that the sub-subject is overexposed by 1 EV. As a result, the controlled shutter speed tv becomes between the maximum shutter speed tVM and the camera shake limit shutter speed tVH. Furthermore, the control time tvy for flash emission is longer than the control shutter speed tv for the flash emission time tF.
and moves as the control shutter speed tv changes. °In addition, in backlight flash mode, the amount of light from the flash is corrected based on the brightness difference between the main subject and sub-subject, so even if the distance to the subject is the same as in dark flash mode, the MI@t of flash emission is
lltvy may be different.

Next, the S2 routine will be explained using FIG. 16.

First, initialize CCO2 (#601) and check whether the flush required flag is set (#6
02). If the flag is set, set the control shutter speed tv calculated by the AE screen, that is, the exposure time iv, to the timer 2 (tl) built in the CPtJl #6゜3), and set the flash emission start time. Set tvy to timer 3 (t2) (#604). continue,
Start the exposure of C0D2 (#605), and when it opens, start the countdown of timer 2 (tl) and timer 3 (t2) (#606), and then start the countdown of timer 3 (t2).
) becomes 0, fires the flash (#608.#
609). When timer 2 (tl) reaches 0 (exposure time t
v progress), stop the exposure of C0D2 (#607.#6
14). In addition, since the flash emits light during exposure,
typ < tv, and timer 3 (t2) is timer 2
(tt) becomes O sooner.

Next, read out the video signal that has accumulated charge in C0D2.#
615), the video signal is processed by the color separation circuit 16 and the matrix circuit 17 (#616), and is recorded on a floppy disk or the like in the recording section 18, and the process returns to the S1 routine (#617 and #618).

If the flash necessity flag is reset in #602, the flash will not be emitted, so the exposure time tv obtained from the AE screen is set in timer 2 (tl), and charge is accumulated in C0D2 for the exposure time. (#610~#
614). Then, the C0D2 reads out the video signal in which the charge has been accumulated, processes the video signal in the color separation circuit 16 and the matrix circuit 17, records it on a floppy disk, etc. in the recording section 18, and returns to the S1 routine. (#614-#618).

〔Effect of the invention〕

As described above, according to the present invention, the solid-state imaging device preferably measures the time for the accumulated charge of the imaging device to overflow before photographing, and performs photometry based on the overflow time. By calculating the charge accumulation time of the element, for example, each photometric information for AEill calculation, AF calculation, AWB calculation, etc. is collected using only the solid-state image sensor for imaging. There is no need for a dedicated photometric element for collecting data, and the camera can be configured compactly. Moreover, it contributes to a reduction in the number of parts and can reduce product costs.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of the circuit configuration of a still video camera according to the present invention, and FIGS. 2(a) to (d) are diagrams showing one embodiment of the optical system of the still video camera according to the present invention. Figure 3 shows an example of the AF optical system, Figure 4 (a)
(b) is AEIII! A diagram showing a time chart of optical operation, Figure 5 is a view of the COD viewed from the front, and Figures 6 (a) to (
C) is the second optical system of the still video camera according to the present invention.
7(a) to 7(C) are diagrams showing a third embodiment of the optical system of a still video camera according to the present invention, and FIG. 8 is a diagram showing a third embodiment of the optical system of a still video camera according to the present invention.
Figure 9 shows the main routine of the n sequence, Figure 9 shows the subroutine 81, Figure 10 shows the Tov setting routine of the subroutine, Figure 11 shows the AWB calculation routine of the subroutine, Figure 12. 13 shows the AE screen of the subroutine, FIG. 14 shows the AE operation routine of the subroutine, and FIGS. 15(a) to (d)
16 is a diagram showing the start timing of flash emission, and FIG. 16 is a diagram showing routine 82 of the subroutines. DESCRIPTION OF SYMBOLS 1... CPU, 2... CCD, 3... CCD drive circuit, 4... Overflow detector, 5... Clock generator, 6... Counter, 7... Switch circuit,
8-10... Integrator, 11... Optical system drive unit, 20
...A/D converter, A...Photographing lens, B...Focusing lens, C...Low pass filter, D...
・・AF optical system, Dl... Condenser lens, Dl・
... Separator lens, E... Diffusion plate, F... Diffusion plate lens, G... Total reflection mirror SW1 to SW5...
switch. Patent applicant Minolta Camera Co., Ltd. Representative
People Patent Attorney Etsu Kotani Shunma
Chief Patent Attorney 1) Masamukai Patent Attorney Takao Ito (a) n! 1-nl, n舅n2^n3 Figure (b) Figure

Claims (1)

[Claims] 1. In a still video camera that takes pictures with a solid-state image sensor, there is a means for measuring the time until the accumulated charge of the solid-state image sensor reaches a certain amount, and distance measurement and photometry based on the time obtained by the measuring means. means for calculating each charge accumulation time in the solid-state image sensor for performing the above, and means for calculating the AF control condition and each photographing condition by accumulating the charge in the solid-state image sensor for each calculated time. A still video camera featuring