JP3467049B2 - Video camera and photometric method thereof - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a video camera (including a still / movie video camera and a still video camera) that performs photometry of an object using a video signal obtained from a solid-state electronic image pickup device and determines exposure conditions. And its photometric method.

[0002]

BACKGROUND ART In a camera having an automatic exposure (so-called AE) function, photometry is necessary to determine an exposure condition. There are various methods for photometry. One of them is to arrange a photometric element in front of the camera. Although this method has a simple configuration, it has an essential problem that the photometric area does not match the shooting area. This problem is particularly noticeable when the field of view is changed using a zoom lens. In order to solve this problem, it is necessary to change the photometric area of the photometric element in conjunction with the zoom lens of the imaging system, which requires a large-scale mechanism.

A method in which a photometric element is incorporated in the image pickup optical system so that the photometric area coincides with the image pickup area (so-called TTL photometry).
There is also. This method requires a beam splitter, an optical path changing element, etc. in the image pickup optical system, which leads to a decrease in sensitivity due to an increase in size of the optical system and a decrease in light transmittance. Moreover, when a mirror is used, there are problems in terms of durability and reliability.

Therefore, in a video camera equipped with a solid-state electronic image pickup device (CCD or the like) to obtain a video signal representing a subject image, the video signal output from the solid-state electronic image pickup device is integrated over an appropriate photometric region. A method of obtaining a photometric value is considered. According to this method, there is an advantage that the image pickup area and the photometric area are completely coincident with each other, and an extra optical system for increasing the size is not required. Also,
By electrically processing the video signal obtained from the solid-state electronic image sensor, variations such as average photometry, partial photometry, and split photometry are possible, and it is possible to set the exposure conditions corresponding to various shooting environments. The range of applications expands.

However, the dynamic range of the CCD is narrow at the limit of about 4 EV. Therefore, if there is a high-luminance portion in the photometric area, the video signal of the high-luminance portion is saturated and accurate photometric value data cannot be obtained, and an error occurs in the photometric value of the entire photometric area. There is a problem. In that case, there is a problem that proper exposure conditions are not set in the video camera and the subject is not properly exposed.

[0006]

DISCLOSURE OF THE INVENTION It is an object of the present invention to provide a video camera and a photometric method therefor capable of performing accurate photometry by using a video signal obtained from a solid-state electronic image pickup device and setting an appropriate exposure condition. And

[0007]

[0008]

[0009]

[0010]

[0011]

[0012]

According to a first aspect of the present invention, in a video camera provided with an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the image signal, a video signal outputted from the solid-state electronic image pickup device. Based on the luminance signal component extracting means for extracting the component relating to the luminance signal from, and the component relating to the luminance signal obtained from a partial area within the photographing area among the components relating to the luminance signal extracted by the luminance signal component extracting means. Among the components relating to the luminance signal extracted by the partial photometric value calculating means for calculating the partial photometric value and the luminance signal component extracting means, the luminance signal obtained from the entire area within the photographing area and larger than the partial area Average photometric value calculating means for calculating the average photometric value based on the component, partial photometric value calculated by the partial photometric value calculating means When the determination means determines whether the partial photometric value is within the first range defined for the partial photometric value, and the determination means determines that the partial photometric value is not within the first range. Based on at least one of the partial photometric value and the average photometric value so that the partial photometric value approaches the first range and the average photometric value approaches the second range defined for the average photometric value, respectively. Exposure condition determining means for determining a new exposure condition for the photometric value recalculation process, and the solid-state electronic image pickup device corresponding to the partial area and the whole area according to the new exposure condition determined by the exposure condition determining means. The components related to the luminance signal are respectively extracted from the video signals output from the light receiving regions of, and the partial photometric value and the The luminance signal component extraction means to the photometric value recalculation processing of fine average photometric value, characterized in that it comprises a control means for controlling the partial photometric value calculating means and the average photometric value calculating means.

The present invention also provides the above photometric method.

According to the first invention, the partial photometric value and the average photometric value are calculated. It is determined whether the calculated partial photometric value falls within a first range defined for the partial photometric value. When the partial metering value is not within the first range, the partial metering value and the partial metering value are set so that the partial metering value approaches the first range and the average metering value approaches the second range defined for the average metering value, respectively. New exposure conditions for the photometric value recalculation process are determined based on at least one of the average photometric values. The photometry value recalculation processing of the partial photometry value and the average photometry value is performed again according to the determined new exposure condition.

[0016]

According to the present invention, when the reliability of the calculated partial photometric value is low, the partial photometric value calculation process and the average photometric value calculation process are performed again. Even if there is a high-brightness part in some areas and the video signal of that high-brightness part is saturated and the accurate average photometric value cannot be obtained due to the effect, if the partial photometric value is not accurate, The partial photometric value calculation process and the average photometric value calculation process are repeated. Therefore, a relatively accurate average photometric value can be obtained.

It is preferable that the photometric value recalculation process be completed by repeating a predetermined number of times.

According to a second aspect of the present invention, in a video camera having an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the video signal, a video signal outputted from the solid-state electronic image pickup device. A luminance signal component extracting means for extracting a component relating to the luminance signal from the luminance signal component, and a component relating to the luminance signal obtained from a plurality of predetermined regions of the photographing region among the components relating to the luminance signal extracted by the luminance signal component extracting device. Photometric value calculating means for calculating each photometric value, and determining means for determining whether or not all of the plurality of photometric values calculated by the photometric value calculating means are within the ranges corresponding to the plurality of predetermined areas, respectively. , The determination means determines that at least one of the plurality of photometric values is not within the corresponding range. Is at least one of said corresponding plurality of photometric values to approach within the scope of the range photometric value is determined not fall within the corresponding when the
Exposure condition determining means for determining a new exposure condition for the photometric value recalculation process, and the solid-state electrons corresponding to the plurality of predetermined regions according to the new exposure condition determined by the exposure condition determining means. Extracting the luminance signal component from the video signal output from the light receiving area of the image sensor, and extracting the luminance signal component so as to calculate each photometric value corresponding to the plurality of predetermined areas from the extracted luminance signal component And a control means for controlling the photometric value calculation means.

The present invention also provides the above photometric method.

According to the second aspect of the invention, each photometric value representing the brightness of a plurality of predetermined areas of the photographing area is calculated. It is determined whether all of the calculated photometric values are within the ranges corresponding to the predetermined regions. When at least one photometric value of the plurality of photometric values is not within the corresponding range, a new exposure condition for the photometric value recalculation processing is determined so as to approach the corresponding range. According to the determined new exposure condition, recalculation processing of each photometric value corresponding to the plurality of predetermined areas is performed. Highly reliable and relatively accurate photometric values can be obtained.

Also in the second aspect of the invention, the photometric value recalculation process is repeated so that the photometric value determined not to be within the corresponding appropriate range is determined to be within the corresponding appropriate range, and the photometric value is determined. It is preferable to count whether or not the value recalculation process is repeated a predetermined number of times, stop the photometric value recalculation process in response to counting the predetermined number of times, and set the already calculated value as the photometric value.

As a result, the photometric value can be obtained even when photometry is performed on an extremely bright or extremely dark subject for which photometric processing is impossible.

In both the first invention and the second invention, the range is empirically determined to be most suitable under trial and error in accordance with accuracy, error, etc. used in the video camera. To be

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment in which the present invention is applied to a digital still camera will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing a digital circuit of an embodiment of the present invention.
It is a block diagram which shows the electric constitution of a still camera.

A clock signal generation circuit (hereinafter referred to as CG) 1 includes a clock signal CLK, a horizontal transfer pulse H for driving the horizontal transfer path of the CCD 4, a substrate extraction pulse SUB for sweeping unnecessary charges, and an A field vertical transfer. A pulse VA and a B field vertical transfer pulse VB are generated. Further, CG1 generates a field index signal FI and an X timing signal XTM for strobe emission.

The clock signal CLK is given to a synchronizing signal generating circuit (hereinafter referred to as SSG) 2, and the SSG2 generates a horizontal synchronizing signal HD and a vertical synchronizing signal VD based on the clock signal CLK and gives it to CG1.

The horizontal transfer pulse H is given to the CCD (solid-state electronic image pickup device) 4, and the substrate extraction pulse SUB and the A field vertical transfer pulse VA are passed through the V driver 5.
The B field vertical transfer pulse VB is applied to the CCD 4 via the V driver 6.

The field index signal FI, the X timing signal XTM and the horizontal synchronizing signal HD are
Given to 3. A shutter enable signal TS indicating that the exposure condition has been set from the CPU 3 to the CG 1.
An electronic shutter control signal TS1 for starting exposure in EN and CCD 4 is applied.

In the CCD 4, the substrate extraction pulses SUB, A
By the field vertical transfer pulse VA, the B field vertical transfer pulse VB, and the horizontal transfer pulse H, interlaced shooting is performed, and video signals of the A field and the B field (color sequential signals of GRGB) are alternately generated every one field period. Are sequentially read. The driving of the CCD 4 (imaging and reading of a video signal) is performed at least at the time of photographing and in the photometric processing prior thereto.

The diaphragm 21 is controlled by a diaphragm control circuit 22 operated by the CPU 3. A subject image is formed on the CCD 4 via the diaphragm 21, and a video signal representing the subject image is output.

The video signals of the A field and the B field output from the CCD 4 are given to a color separation circuit 8 through a correlated double sampling circuit (CDS) 7 and three primary colors representing a subject image, G (green), R ( Red) and B
It is separated into (blue) color signals.

The color signals G, R and B are subjected to color balance adjustment by a gain control circuit (hereinafter referred to as GCA) 9 and then gradation correction is performed by a gamma correction circuit 10 for clamping and re-loading. Input to the sampling circuit 11.

The clamp and resampling circuit 11 is
The three color signals R, G, B are clamped and re-converted into GRGB color sequential signals by resampling. This color sequential signal is input to the gain control and blanking circuit 12. The gain control and blanking circuit 12 amplifies the color sequential signal to an appropriate level for recording and adds the blanking signal to it. The output signal of the circuit 12 is subsequently converted into digital image data by the A / D converter 13.

As will be described later in detail, prior to photographing, photometric processing and exposure control (control of iris and shutter speed) based on the photometric value are performed. This photometric processing is GCA9.
Based on the output signal of Shooting is performed after such photometric processing and exposure control. Then, the video signal obtained from the CCD 4 by photographing is the above-mentioned circuit 10, 1
It becomes digital image data through 1, 12 and 13 and is processed by Y / C separation, data compression, etc. by an image data processing circuit (not shown) and then recorded on a recording medium such as a memory card. Become.

For photometric processing, a Y _L combining circuit 14, a gate circuit 15, an integrating circuit 16 and an amplifying circuit 17 are provided. An example of a specific electrical configuration of these circuits is shown in FIG. The CPU 3 outputs a window signal WIND that controls the gate circuit 15 and a reset signal HLRST that resets the integration circuit 16. These signals WIND
The timing of HLRST will be described later. Further, in this embodiment, the CPU 3 has an A / D converter 18 built-in.

The color signals R, G and B output from the gain control circuit 9 are added by the Y _L synthesizing circuit 14,
A relatively low frequency luminance signal Y _L (hereinafter simply referred to as luminance signal Y _L
Is generated). The luminance signal Y _L passes through the gate circuit 15 while the window signal WIND is being applied in the required horizontal scanning period. The integrating circuit 16 is reset when the reset signal HLRST is given,
After that, the luminance signal Y _L input from the gate circuit 15 is integrated. The integrated signal of the integrating circuit 16 is amplified by the amplifying circuit 17, and immediately before the integrating circuit 16 is reset, the A /
Converted to digital integral data by D converter 18,
It is taken in by the CPU 3. The reference voltage divisions V1 and V2 of the integrating circuit 16 and the amplifying circuit 17 give an appropriate offset thereto.

In this embodiment, average photometry (hereinafter referred to as AV photometry) that measures the average brightness of almost the entire field of view, and average brightness of the upper part of about 1/3 of the field of view are measured. Average upper metering (hereinafter referred to as AV upper metering), average lower metering (hereinafter referred to as AV lower metering) that measures the average brightness of the lower part of the field of view, and brightness of the main subject in the field of view The spot photometry (hereinafter, referred to as SP photometry) for measuring is performed.

SP photometry is effective when the brightness of the main subject in the field of view and the brightness of the background are different and it is necessary to set an appropriate exposure condition in accordance with the brightness. Further, in the case of outdoor photography, the sky is often captured in the upper area within the field of view. Therefore A
When V photometry is performed and the exposure condition is determined accordingly and the image is taken, the lower region in the visual field may become dark. In such a case, AV lower photometry is effective.

Further, if there is a very dark or very bright portion in a specific portion within the field of view, the photometric value obtained due to saturation will be inaccurate. For this reason, the CPU 3 has an appropriate range according to the exposure condition corresponding to each photometry.
If the obtained photometric value is not within the proper range, both photometrics are performed. Also,
When AV photometry is performed, the photometric value obtained as AV photometry may be partially saturated even within an appropriate range. In this case, the photometric value obtained by AV photometry cannot be said to be proper. Therefore, if even one of the photometric values obtained by the AV upper photometry, the AV lower photometry or the SP photometry is out of the proper range, the re-photometry is performed for the AV photometry.

Since it is considered that the A field image and the B field image which form one frame represent the field images at substantially the same time, in this embodiment, the video signal of the A field is AV upper photometry, AV lower photometry and AV lower photometry. For AV photometry, the B field video signal is used for SP photometry, respectively. The AV upper photometry is performed in almost the first half of the A field, and the AV lower photometry is performed in the latter half of the A field. AV metering value is A
It is calculated from the integrated value for V upper photometry and the integrated value for AV lower photometry.

Further, in this embodiment, the integration by the integration circuit 16 and the A / D conversion operation and addition processing by the A / D converter 18 are alternately performed every horizontal scanning period.

FIG. 3 shows an AV upper photometry area, an AV lower photometry area, an AV photometry area, and an SP photometry area, which are set in the photographing area 20 of the CCD 4.

The AV upper photometry area is almost 1 of the photographing area 20.
Set over the upper part of / 3. In this embodiment, AV
The upper photometry area is set for a period of 40 μs after 16.15 μs has elapsed from the falling edge of the horizontal synchronizing signal HD (at the start of the horizontal scanning period) in the horizontal direction, and the vertical direction from the 35th horizontal scanning line. It is set up to the 100th horizontal scan line.

The AV lower photometry area is almost 2 of the photographing area 20.
Is set over the lower region of / 3. In this embodiment, the AV lower photometry area is set for a period of 40 μs after the lapse of 16.15 μs from the trailing edge of the horizontal synchronizing signal HD (the start point of the horizontal scanning period) in the horizontal direction, and the 101st position in the vertical direction. It is set between the horizontal scan line and the 246th horizontal scan line.

The AV metering area is a combination of the AV upper metering area and the AV lower metering area.
It is set over almost all 20 areas. In this embodiment, A
In the V photometry area, after the lapse of 16.15 μs from the falling edge of the horizontal synchronizing signal HD (at the start of the horizontal scanning period) in the horizontal direction, 40
The period is μs, and the vertical direction is from the 35th horizontal scanning line to the 246th horizontal scanning line.

The SP photometric area is set as a small area at an arbitrary position within the photographing area 20. In this embodiment, the SP metering area is set at the center of the photographing area 20, and the horizontal direction is 14 μs after 29.15 μs has elapsed from the fall of the horizontal synchronizing signal HD.
In the vertical direction from the 101st horizontal scan line to the
It is set up to the 208th horizontal scan line.

Both the AV upper photometry and the AV lower photometry are performed in the A field period, and only the setting lines of the horizontal scanning lines in the vertical direction are different. Because of this
In both of the V upper photometry and the AV lower photometry, FIG.
As shown in, from the fall of the horizontal synchronizing signal HD
Window signal WIN with pulse width 40 μs after 16.15 μs
D is supplied to the gate circuit 15. This window signal W
While IND is applied, the gate circuit 15 allows the input luminance signal Y _L to pass through, and the luminance signal Y _L is supplied to the integrating circuit 16
To enter.

The integrating circuit 16 has already been reset in the preceding field and integrates the luminance signal Y _L which has passed through the gate circuit 15 and is input. Window signal WIND
Becomes L level and the input of the luminance signal Y _{L to} the integrating circuit 16 is stopped, the integrated output of the integrating circuit 16 is held as it is and the integrated output of the integrating circuit 16 is A / D converted in the CPU 3. It is converted into digital data by the device 18. In this embodiment, the time required for A / D conversion is
15 μs. After that, the integrating circuit 16 is reset by the horizontal line reset signal HLRST given from the CPU 3 to prepare for the next integrating operation.

A memory attached to the CPU 3 (for example, RA
M) has an AV upper integrated data storage area for storing data obtained by AV upper photometry and an AV lower integrated data storage area for storing data obtained by AV lower photometry.

The AV upper integrated data storage area is cleared in synchronization with the 34th horizontal synchronizing signal HD. A / D
The integrated value converted into digital data by the converter 18 is added to the previous data (which is cleared in the first case and is zero) and stored in this AV upper integrated data storage area.

The A / D conversion by the A / D converter 18, the reset of the integrating circuit 16 and the addition processing of the integrated data are performed by the following steps.
It is performed in the 36th horizontal scanning period.

As described above, the integration of the luminance signal Y _L by the integrating circuit 16 on one horizontal scanning line in the AV upper photometry area, and the A / D conversion and integration of the integrated signal obtained by this integration The resetting of the circuit 16 and the addition of the integrated data to the memory are alternately repeated every horizontal scanning period. Then, this repetition is performed until the 100th horizontal scanning period.

At the 101st horizontal scanning period, AV
It becomes the processing of lower photometry.

The AV lower integrated data storage area is cleared in synchronization with the 100th horizontal synchronizing signal HD. A /
The integrated value converted to digital data by the D converter 18 is the previous data in this AV lower integrated data storage area (it is zero because it is cleared in the first case).
Is added and stored.

The A / D conversion by the A / D converter 18, the reset of the integrating circuit 16 and the addition processing of the integrated data are performed in the next 102nd horizontal scanning period as in the case of the AV upper photometry.

The integration of the luminance signal Y _L by the integrating circuit 16 on one horizontal scanning line in the AV lower photometry area, A / D conversion of the integrated signal obtained by this integration, reset of the integrating circuit 16 and memory The addition of the integral data to the above is alternately repeated every horizontal scanning period as in the case of the AV upper photometry. Then, this repetition is performed until the 246th horizontal scanning period, that is, over the entire AV lower photometry area.

Thus, the AV photometric value is obtained from the data stored in the AV upper integrated data storage area and the data stored in the AV lower integrated data storage area.

In SP photometry in the B field period, as shown in FIG. 5, the window signal WIND having a pulse width of 14 μs is the 101st horizontal synchronizing signal HD.
Is given to the gate circuit 15 29.15 μs after the fall of
During this period, the integrating circuit 16 integrates the input luminance signal Y _L. The window signal WIND is output every other horizontal scanning period.
It is performed until the 207th horizontal scanning period. The A / D conversion of the integrated signal output from the integrating circuit 16 into the integrated data, the resetting of the integrating circuit 16 and the addition of the integrated data in the memory are performed in the same horizontal scanning operation as the above-mentioned AV photometry. Will take place during the period.

In this way, the luminance signal Y _L is integrated every other horizontal scanning period, and A / D conversion and other processing are performed in the next horizontal scanning period after the integration. Even if a D converter is used, it can be sufficiently dealt with. Then, even if the integration is performed every other horizontal scanning line, even SP photometry can be performed on 54 horizontal scanning lines so that a sufficient amount of integration data can be obtained to obtain a photometric value. .

In the above description, AV upper part, AV lower part and AV metering are performed in the A field period, and SP metering is performed in the B field period. Conversely, SP metering is performed in the A field period and AV upper part in the B field period. , AV lower part and AV metering may be performed, or needless to say, only AV metering (AV upper part, AV lower part metering) or SP metering may be carried out in both fields or one field. .

FIG. 6 is a graph showing the relationship between the brightness value and the voltage (detection voltage) for each horizontal scanning range of the AV photometric area input to the A / D converter 18 of the CPU 3. The detection voltage shown on the vertical axis in FIG. 6 corresponds to the integrated amount of one horizontal scanning range (40 [μs] in time) of the AV photometric area, and is calculated when this voltage is added to the entire AV photometric area. The luminance value shown on the horizontal axis of FIG. 6 is obtained.

Graphs A _{1 to} A ₄ for calculating the brightness value
Determines which graph to use depending on the exposure conditions. The graph of A ₁ is used when the aperture is F3.5 and the shutter speed is 1/15 sec. The graph of A ₂ is used when the aperture is F3.5 and the shutter / speed is 1/120 sec.・ When the speed is 1/60 seconds, the graph of A ₃ is used, and the aperture is F14 and the shutter speed is 1/240.
At the time of second, the glara of A ₄ is used.

In this digital still camera, the photometric accuracy range is set in order to obtain a relatively reliable photometric value in consideration of integration error, A / D conversion error and the like. This photometric accuracy range is about 375 [mv] from the detection voltage to 3000
It is set to about [mV]. The photometric accuracy range is about 3 EV when expressed using the EV value. When the obtained detected voltage is outside this photometric range, the exposure conditions are changed to perform both photometric measurements.

Although FIG. 6 is for the AV photometric area, appropriate ranges are also set for the AV upper photometric area, the AV lower photometric area, and the SP photometric area. SP
Since the horizontal scanning range of the photometric area is narrow, the magnitude of the detected voltage in the proper range will be small.

FIG. 7 is a flow chart showing the overall operation of the photometric processing performed by the CPU 3, and FIGS. 8 to 18 are flow charts showing the procedure of the re-photometric determination processing. Further, FIG. 19 shows the relationship between the photometric parameters set by the CPU 3, the exposure conditions (aperture value, shutter speed) and the photometric area.

When the photometric processing is started, the photometric parameter is set to 0 to initialize the exposure conditions (step 31). The photometric counter is set to 0 (step 32).

Subsequently, the photometric conditions corresponding to the photometric parameters are set (step 33). In the initial setting, the photometric parameter is set to 0, so refer to it and set the aperture to F3.5 and the shutter speed to 1 so that the photometric condition is EV10.5.
It is set to / 120. If the aperture 21 is not set to that aperture value (NO in step 34), the number of drive pulses required to set F3.5 is calculated (step 35) so that the aperture value matches the photometric conditions. Aperture driven by aperture drive circuit 22
21 is driven (step 36).

Further, the CCD 4 is driven by the drivers 5 and 6.
It is driven so that the shutter speed matches the photometric conditions (step 37).

The video signal output from the CCD 4 is a CD
S7, through the color separation circuit 8 and GCA9 Y _L synthesizing circuit
Given to 14. As a result, as described above, the Y _L combining circuit
14, the gate circuit 15, the integrating circuit 16, and the amplifying circuit 17 are driven (step 38). From AV upper photometry data, AV lower photometry data and SP photometry data, AV upper brightness value,
The AV lower luminance value, the AV luminance value and the SP luminance value are calculated (step 39).

If each calculated brightness value is outside the proper range, accurate exposure control cannot be performed. For this reason, it is determined from the respective brightness values whether or not re-photometry is necessary (step 40). The procedure of this re-photometry determination process is shown in FIGS. 8 to 18. This processing will be described next.

Subsequently, the photometric counter is incremented (step 41). When the re-photometry is no longer necessary, the photometry processing ends (step 42).

Of the flowcharts showing the procedure of the re-photometry determination process of FIGS. 8 to 18, FIGS. 8 to 10 show the determination process by the first photometry, and FIGS. 11 to 17 show the second photometry. FIG. 18 shows the determination processing by the third photometry processing.

Referring to FIG. 8, since the photometry counter is set to 0 in the first photometry processing, AV
It is determined whether or not the brightness value (EV value) is within the proper range of EVs 9 to 12 (YES in step 51 of FIG. 8, step 52). Next, it is determined whether the AV lower luminance value is within the proper range of EV9 to 12 (step 53 in FIG. 8). If it is within the appropriate range, the SP luminance value is further within the proper range of EV9 to 12. It is determined whether or not it is within the range (step 54 in FIG. 8). When the SP brightness value is also within the proper range, it is determined whether the AV upper brightness value is within the proper range of EVs 9 to 12 (FIG. 8).
Step 55).

When the AV photometric value, the AV lower photometric value, the SP photometric value, and the AV upper luminance value are all within the proper luminance range of EVs 9 to 12, the photometric parameter is set to 1 and the photometric processing ends. (FIG. 8 step 57, FIG. 7 step 42).

The AV luminance value or the AV lower luminance value is EV9.
If the following is true, the photometric parameter is set to 2 (see FIG. 8).
Step 58). EV when the photometric parameter is set to 2
The shutter speed is slowed down so that the photometric condition is 7.5.
It is set to 1/15 second. In addition, re-photometry is performed based on all areas (step 33 in FIG. 7).

Even if both the AV luminance value and the AV lower luminance value are within the proper range, when the SP luminance value is EV9 or less (steps 52 to 54 in FIG. 8), according to the value of the AV upper luminance value. The setting of photometric parameters can be changed (step 59 in FIG. 8).

The SP brightness value is EV9 or less, and AV
When the upper luminance value is EV9 or less, the photometric parameter is set to 3 (step 60). As a result, the aperture value F3.5,
At the shutter speed of 1/15 second, re-photometry of all areas of the AV area, AV upper area, AV lower area and SP area is performed (step 60 in FIG. 8).

When the SP brightness value is EV9 or less and the AV upper brightness value is EV9 to 12, the photometric parameter is set to 4, the aperture value is F3.5, the shutter speed is 1/15 seconds, and the AV area, AV Re-photometry of the lower area and the SP area is performed. Since the AV upper luminance value is in the proper range, re-photometry is not performed (step 61 in FIG. 8).

When the AV upper luminance value is EV12 or more, the photometric parameter is set to 9. When the photometric parameter is set to 9, accurate photometry cannot be performed because the SP area is dark (step 54 in FIG. 8), and accurate photometry cannot be performed because the AV upper area is too bright (step 8 in FIG. 8). 59). At this time, the AV luminance value cannot be obtained without error, and the already calculated AV luminance value is used as the luminance value of the AV area. However, re-photometry is performed on the AV upper area and the SP area in order to calculate accurate luminance values in the SP area and the AV upper area (step in FIG. 8).
62). In this case, AV obtained by re-photometry is preferable.
The AV brightness value may be corrected with reference to the upper brightness value and the SP brightness value.

When all of the AV luminance value, the AV lower luminance value and the SP luminance value are within the proper range and the AV upper luminance value is EV9 or less, the photometric parameter is set to 5 (step 63 in FIG. 8). . In this case, re-photometry is performed only in the upper AV region with an aperture value of 3.5 and a shutter speed of 1/15 seconds. When the photometric parameter is set to 5, all of the AV brightness value, AV lower brightness value and SP brightness value are EV9.
It is within the proper range of ~ 12 and only the AV upper area is dark (steps 52 to 55 in Fig. 8). In this state, if re-photometry is performed with an aperture value of F3.5 and a shutter speed of 1/15 second, the AV lower luminance value and the SP luminance value become large, and neither falls within the proper range. Therefore, the AV luminance value includes many errors. Therefore, re-photometry is performed only on the upper part of the AV.

When the AV brightness value is EV12.5 or higher (see FIG. 8)
Step 52), the setting of the photometric parameter changes according to the SP brightness value (step 71 in FIG. 9). SP brightness value is EV
When it is less than 12.5, the photometric parameter is set to 12 (Fig. 9).
Step 72), if EV12.5 or above
It is set to 13 (step 73 in FIG. 9). In this case, re-photometry is performed at an aperture value of F14 and a shutter speed of 1/60 seconds in both cases, but when the SP brightness value is EV12.5 or less, the SP brightness value is considered to be within the proper range, so the AV area other than the SP area is considered. , AV upper area and AV lower area are re-metered. SP
When the brightness value is EV12.5 or higher, all areas are re-metered.

Even when the AV luminance value is within the proper range of EV9 to 12 (step 52 in FIG. 8) and the AV lower luminance value is EV12.5 or more, the setting of the photometric parameter changes according to the value of the SP luminance value. (FIG. 9, step 74).

When the SP brightness value is EV12.5 or less, the photometric parameter is set to 10 (step 75 in FIG. 9), and EV12.5
In the above case, the photometric parameter is set to 11 (step 76 in FIG. 9). In this case as well, re-photometry is performed at an aperture value of F14 and a shutter speed of 1/60 seconds, and the SP brightness value is EV1.
When the brightness is 2.5 or less, the SP brightness value is considered to be within an appropriate range, so that the AV area, the AV upper area, and the AV lower area other than the SP area are re-metered. When the SP brightness value is EV12.5 or higher, all areas are re-metered.

Both the AV luminance value and the AV lower luminance value are within the proper range of EV9 to 12, and the SP luminance value is EV1.
When it is 2.5 or more (steps 52, 53, 54 in FIG. 8), the setting of the photometric parameter changes according to the value of the AV upper luminance value (step 76 in FIG. 10).

When the AV upper luminance value is EV9 or less, the photometric parameter is set to 6 (step 79 in FIG. 10), and EV is set.
When it is 12.5 or more, the photometric parameter is set to 7 (step 82 in FIG. 10). When the AV upper luminance value is EV9 to 12, the photometric parameter is set according to the value of the AV luminance value (step 78 in FIG. 10).

When the AV upper luminance value is EV12.5 or more, it can be judged that the AV upper luminance value gives a large error to the AV luminance value. Therefore, when the photometric parameter is set to 7, the aperture value F14 and the shutter are set. Re-photometry of all areas is performed at a speed of 1/60 seconds (step 82 in FIG. 10).

When the AV upper luminance value is within the range of EV9 to 12 (step 76 in FIG. 10) and the AV luminance value is EV11.5 or less (step 78 in FIG. 10), the photometric parameter is set to 6 and the aperture value is set. All areas are re-metered at F14 and shutter speed 1/60 seconds (step 79 in Fig. 10). At this time, the AV brightness value is compared with the AV brightness value obtained by re-photometry, and the AV brightness value obtained in order to use the more accurate one is stored (step 80 in FIG. 10).

When the AV upper luminance value is in the range of EV9 to 12 (step 76 in FIG. 10) and the AV luminance value is EV12.5 or more (step 78 in FIG. 10), the photometric parameter is set to 13 and the aperture value F14, All areas are re-metered at a shutter speed of 1/60 seconds (step 79 in Fig. 10).

When the AV luminance value, the AV lower luminance value and the SP luminance value are all within the proper range, the AV upper luminance value is E
When V12 or more (steps 52 to 55 in FIG. 8), the setting of the photometric parameter changes according to the value of the AV brightness value (step 83 in FIG. 10). When the AV brightness value is EV11.5 or less, the photometric parameter is set to 8 (step 84 in FIG. 10), and when the AV brightness value is EV11.5 or more, the photometric parameter is set to 12 (step 86 in FIG. 10). In both of these cases, the aperture value is set to F14 and the shutter speed is set to 1/60 second, and A
The photometry of the V area, the AV upper area, and the AV lower area is performed again. However, when the AV brightness value is EV11.5 or less, the AV brightness value is stored for comparison with the AV brightness value obtained by re-photometry (step 85 in FIG. 10).

When the first photometric process is completed, the photometric counter is incremented (step 4 in FIG. 7).
1), photometric counter becomes 1. When re-photometry is performed, an image is taken at an aperture value and shutter speed according to the photometric area, and the respective brightness values are calculated (steps 33 to 39 in FIG. 7).

Referring to FIG. 11, if the photometric parameter is larger than 5, it is determined whether the value of the photometric counter is 1 or not (steps 90 and 91), and re-photometric determination processing is performed according to the magnitude of the photometric parameter. (Steps 92 to 99).

If the photometric parameter is set to 6 (YES in step 92 of FIG. 11), the SP obtained by re-photometry
The brightness value is determined (step 102 in FIG. 12). If the SP brightness value is within the proper range of EV13 to 16, the AV brightness value is determined (step 103 in FIG. 12). AV brightness value is EV12.5
In the following cases, the stored AV brightness value (step 80 in Fig. 9) is judged to be more appropriate and is loaded (Fig.
12 step 104) The photometric processing is completed (step 12 in FIG. 12).
Five ). When the AV brightness value is EV12.5 or more, it is determined that the brightness value obtained by the re-photometry is more appropriate, and the photometry processing ends (step 105 in FIG. 12).

Even if the SP brightness value is EV16 or more, the magnitude of the AV brightness value is determined (step 102 in FIG. 12,
106). When the AV brightness value is EV14.5 or more, the photometric parameter is set to 15 and when the AV brightness value is EV14.5 or less, the photometric parameter is set to 17 (FIGS. 12, steps 107 and 110).
), Anyway, aperture value F14, shutter speed 1/240
Re-photometry is performed for all areas in seconds (step 108 in FIG. 12).

When the photometric parameter is set to 7 (step 93 in FIG. 11), the value of the AV upper luminance value is determined (step 101 in FIG. 12), and the AV upper luminance value is changed from EV12.
If it is up to 15, the same processing as when the photometric parameter is 6 is performed (steps 102 to 108 and 110 in FIG. 12). AV
When the upper luminance value is EV15.5 or higher, the SP luminance value is judged (step 109 in FIG. 12), and when it is EV16 or higher, the photometric parameter is set to 17 (step 110 in FIG. 12).
When the SP brightness value is EV13 to 16, the SP brightness value is appropriate, so the photometric parameter is set to 16, and the AV outside the SP area is set.
The area, the AV upper area, and the AV lower area are re-photometered (step 111 in FIG. 12).

When the photometric parameter is set to 9 (step 94 in FIG. 11), the photometric parameter is reset to 19 (step 112 in FIG. 12), the aperture value F14, the shutter speed 1 /
In 60 seconds, the AV area, the AV upper area, and the AV lower area are re-metered.

When the photometric parameter is set to 10 (step 95 in FIG. 11), the value of the re-photometered AV lower luminance value is determined (step 113 in FIG. 13), and the AV lower luminance value is in the range of EV12 to 15 If it is within the range, it is within the proper range and the photometric processing is terminated (step 114 in FIG. 13). If the AV lower brightness value is EV15 or higher, the photometric parameter is set to 18,
Aperture value F14, shutter speed 1/240, AV area, AV
Re-photometry is performed on the upper area and the AV lower area (step 116 in FIG. 13).

When the photometric parameter is set to 8 (step 95 in FIG. 10), the value of the re-photometered AV upper luminance value is determined (step 117 in FIG. 13). When the AV upper brightness value is EV12 to 15, the AV brightness value is further determined (step 118 in FIG. 13), and when the AV brightness value is EV12.5 or less, the stored AV brightness value is loaded (FIG. 12).
Step 119) Since the stored AV brightness value is relatively appropriate, the photometric processing is completed (step 120 in FIG. 12),
When the AV brightness value is EV12.5 or higher, the AV brightness value obtained by both photometry is judged to be more appropriate than the stored AV brightness value, and the photometry processing is completed (step 120 in FIG. 13).

When the AV upper luminance value is EV 15.5 or more, the measurement parameter is set to 23 (step 121 in FIG. 13).
), The aperture value is F14 and the shutter speed is 1/240, and re-photometry is performed (step 122 in FIG. 13). At this time A
Only the upper V region is in a bright state. At this time, if the photometry is performed again with the aperture value F14 and the shutter speed of 1/240 second,
The luminance value of the area other than the AV upper portion becomes too low, and as a result, the AV luminance value includes many errors. Therefore AV
Only the upper luminance value is re-metered.

When the photometric parameter is 11 (step 97 in FIG. 11), the value of the re-photometered AV luminance value is determined (see FIG.
14 steps 123).

When the AV lower luminance value is EV15 or less, SP
The brightness value is determined (step 124 in FIG. 14), and if the SP brightness value is within the range of EV13 to EV16, each brightness value obtained by re-photometry is determined to be appropriate, and the photometric processing is terminated (FIG. 14). Step 125). When the SP brightness value is EV16 or more, the photometric parameter is set to 20, and re-photometry of the entire area is performed with the aperture value F14 and the shutter speed of 1/240 seconds (steps 126 and 127 in FIG. 4).

Even if the AV lower luminance value is EV15 or more, S
A determination process of the P brightness value is performed (step 12 in FIG. 14).
8). If the SP brightness value is within the range of EV13 to 16, the photometric parameter is set to 21 (step 129 in FIG. 14), the aperture value F14 and the shutter speed of 1/240 seconds are set to A outside the SP area.
Re-photometry processing is performed on each of the V area, the AV upper area, and the AV lower area (steps 129 and 12 in FIG. 14).
7). When the SP brightness value is EV16 or more, the photometric parameter is set to 22, and re-photometry is performed for all areas (step 130 in FIG. 14).

If the photometric parameter is set to 12 (step 98 in FIG. 11), the value of the AV luminance value obtained by re-photometry is determined (step 131 in FIG. 15).

If the value of the AV luminance value is between EV12 and EV15 and is determined to be an appropriate value, the value of the AV lower luminance value is also determined (step 132 in FIG. 15). The lower AV brightness value is also EV12-
If it is determined that the value is between 15 and an appropriate value, the value of the AV upper luminance value is also determined (step 133 in FIG. 15), and all the luminance values of the AV luminance value, the AV upper luminance value and the AV lower luminance value. Is within the range of EV12 to 15, all the brightness values obtained by re-photometry can be judged to be appropriate values, and the photometry processing is terminated (step 134 in FIG. 15).

The AV luminance value or the AV lower luminance value is EV15.
In the above case, the photometric parameter is set to 24 (step 137 in Fig. 15), the aperture value is F14, and the shutter speed is 1/240 sec.
Areas other than the P area are re-metered (step 136 in FIG. 15,
137). Further, when the AV upper luminance value is EV15 or more, the photometric parameter is set to 23, and only the AV upper area is re-photometered at the aperture value F14 and the shutter speed of 1/240 seconds (steps 135 and 136 in FIG. 15).

When the photometric parameter is set to 13 (step 99 in FIG. 11), the AV luminance value, the AV lower luminance value, the AV upper luminance value and the SP luminance value obtained by re-photometry are changed as necessary. Value judgment is performed (Fig. 16 step)
137-140).

The AV luminance value, the AV lower luminance value, and the AV upper luminance value are all within the range of EV12 to 15, and SP
If the brightness value is within the range of EV13 to EV16, it can be determined by re-photometry that an appropriate brightness value has been obtained, and the photometric processing is terminated (step 141 in FIG. 16).

When the AV luminance value, the AV lower luminance value and the AV upper luminance value are all within the range of EV12 to 15 and only the SP luminance value is EV16 or more, the value of the AV luminance value is determined (step in FIG. 16). 142). If the AV brightness value is EV14.5 or less, the AV brightness value is stored (step 143 in FIG. 16), and A
If the V luminance value is EV14.5 or more, the AV luminance value is not stored, and re-photometry of all areas is performed with the aperture of F14 and the shutter speed of 1/240 seconds (steps 144 and 146 in FIG. 16).
).

The AV luminance value or the AV lower luminance value is EV15.
In the above case, the SP brightness value is determined (step 150 in FIG. 17). If the EV brightness value is within the range of EV 13 to 16, the photometric parameter is set to 28 (step 151 in FIG. 17), and EV is set.
If the brightness value is EV16 or higher, the photometric parameter is set to 29 (step 152 in FIG. 17). When the SP brightness value is within the proper range of EV13-16, re-photometry other than the SP area is performed, and when the SP brightness value is EV16 or more, re-photometry is performed for all areas (step 152 in FIG. 17).

Even when the AV upper brightness value is EV15 or more (step 138 in FIG. 16), the value of the SP brightness value is determined (step 147 in FIG. 17). If the EV brightness value is within the proper range of EV13 to 16, the photometric parameter is set to 26 (step 148 in FIG. 17), and if the EV brightness value is EV16 or more, the photometric parameter is set to 27 (step 149 in FIG. 17). When the SP brightness value is within the range of EV13 to 16, re-photometry other than the SP region is performed, and when the SP brightness value is EV16 or more, re-photometry of all regions is performed (step 149 in FIG. 17).
).

When the photometric parameter is set to 5 or less (YES in step 90 in FIG. 11), the subject is dark and the photometric processing is terminated because the photometry is impossible (step 155 in FIG. 18).
).

When the first re-photometry is performed, the photometric counter becomes 2. Therefore, in the second re-photometry, the determination made in step 91 of FIG. 11 is NO, and FIG. 18 step 15
Move on to step 3.

It is determined whether the photometric parameter is set to 15, 20, or 25 (step 18 in FIG. 18).
153), if any of the parameters is set AV
The value of the brightness value is determined (step 154 in FIG. 18), and when the magnitude of the AV brightness value is EV14.5 or more, the stored A
The V luminance value is loaded and the photometric processing is completed (steps 155 and 154 in FIG. 18).

When the photometric parameters are other than 15, 20, and 25 (NO in step 153) or when the AV brightness value is EV14.5 or less, the AV brightness value already obtained is used as the brightness value in the AV area and the photometric processing is performed. End (Fig. 18, step 156)
).

In the photometric parameter determination processing shown in FIG. 1, if neither is suitable, error processing is performed (step 100 in FIG. 11).

[Brief description of drawings]

FIG. 1 is a block diagram of a digital still camera according to an embodiment of the present invention.
It is a block diagram which shows the electric constitution of a video camera.

2 is a circuit diagram showing a more specific electrical configuration of a circuit portion required for photometry in the digital still video camera of FIG.

FIG. 3 shows a photometric area set within a shooting area.

FIG. 4 is a time chart when performing average photometry.

FIG. 5 is a time chart when spot photometry is performed.

FIG. 6 shows the relationship between the detection voltage input to the CPU and the subject brightness.

FIG. 7 is a flowchart showing a procedure of photometric processing by a CPU.

FIG. 8 is a flowchart showing a part of the procedure of re-photometry determination processing.

FIG. 9 is a flowchart showing a part of a procedure of re-photometry determination processing.

FIG. 10 is a flowchart showing a part of a procedure of re-photometry determination processing.

FIG. 11 is a flowchart showing a part of the procedure of re-photometry determination processing.

FIG. 12 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 13 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 14 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 15 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 16 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 17 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 18 is a flowchart showing a procedure of re-photometry determination processing.

FIG. 19 shows a relationship between a photometric parameter and an exposure condition corresponding thereto.

[Explanation of symbols]

3 CPU (control means) 4 CCD (solid-state electronic image pickup device) 14 Y _L combining circuit 15 gate circuit 16 integrating circuit 17 amplifying circuit 18 A / D converter 20 shooting area

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Izumi Miyake 3-1146 Izumi, Asaka City, Saitama Prefecture, Fuji Photo Film Co., Ltd. (56) References JP-A-4-170275 (JP, A) JP-A 2-78379 (JP, A) JP-A 1-217429 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 5/225-5/247

Claims (8)

(57) [Claims] 1. A video camera provided with an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the image signal, wherein the video signal output from the solid-state electronic image pickup device relates to a luminance signal. Luminance signal component extraction means for extracting a component, and among the components related to the luminance signal extracted by the above-mentioned luminance signal component extraction means, the partial photometric value is calculated based on the components related to the luminance signal obtained from a partial area within the photographing area. Partial photometric value calculating means for calculating, of the components related to the luminance signal extracted by the luminance signal component extracting means, the portion within the photographing region and in the portion
The average photometric value calculating means for calculating the average photometric value based on the component relating to the luminance signal obtained from the whole area larger than the area , and the partial photometric value calculated by the partial photometric value calculating means is defined for the partial photometric value. and judging means for judging whether fall first within range, the by determination means, when said portion photometric value is determined not to fall in the first range <br/>囲内is the partial light measurement value There in the first range, the average photometric value average photometric value
It said to approach each second range stipulated in use
At least one of the partial photometric value and the average photometric value
New exposure conditions for photometric recalculation processing
Exposure condition determining means for constant, as well as a new exposure conditions determined by the exposure condition determining means
According to the conditions, components relating to the luminance signal are respectively extracted from the video signals output from the light receiving regions of the solid-state electronic image pickup device corresponding to the partial region and the whole region , and the partial photometric value and A video camera comprising: the luminance signal component extracting means, the partial photometric value calculating means, and the control means for controlling the average photometric value calculating means so as to perform recalculation processing of the average photometric value. 2. The photometric value recalculation processing using the luminance signal component extracting means and the photometric value calculating means, which is performed based on the determination processing by the determining means, is performed by the determining means to determine the partial photometric value as the first predetermined and within the limits of photometric values recalculated control means for repeating as the average photometric value is determined to the second within range, based on the photometric value recalculation process of the control of the photometric value recalculation control means Counting means for counting whether or not it has been repeated a number of times, and
The video camera according to claim 1, further comprising: stop control means for stopping the photometering value recalculation process using the already calculated value as the photometering value. 3. A video camera provided with an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the image signal, wherein the video signal output from the solid-state electronic image pickup device relates to a luminance signal. Luminance signal component extracting means for extracting a component, and among the components relating to the luminance signal extracted by the luminance signal component extracting means, respective photometric values based on the components relating to the luminance signal obtained from a plurality of predetermined regions of the photographing region. photometric value calculating means for calculating, all of the plurality of photometric values calculated by the photometric value calculating means, determining means for determining whether falls within range that corresponds respectively to the plurality of predetermined areas, the determination by means, when at least one photometric values of the plurality of photometric value is determined to be not within the corresponding on Kihan囲内Closer on Kihan囲内the photometric value is determined not within the corresponding on Kihan囲内corresponding
At least Tsunimoto of Ku said plurality of photometric values as
To determine new exposure conditions for photometric recalculation
Exposure condition determining means, and a new exposure strip determined by the exposure condition determining means
According to the situation, a component related to a luminance signal is extracted from a video signal output from the light receiving region of the solid-state electronic image pickup device corresponding to the plurality of prescribed regions, and the extracted components related to the luminance signal are corresponded to the plurality of prescribed regions. A video camera comprising: a luminance signal component extracting means and a control means for controlling the photometric value calculating means so as to calculate each photometric value. The method according to claim 4, wherein said determination means according to the determination process photometric value recalculation processing using the luminance signal component extraction means and the photometric value calculating means is performed based on, fall on Kihan囲内corresponding with the determination process photometric value recalculation control means determined photometric value that no repeats, as determined with the corresponding upper Kihan囲内, based on the photometric value recalculation processing a predetermined number of control of the photometric value recalculation control means Counting means for counting whether or not it has been repeated, and according to the fact that the counting means has counted a predetermined number of times,
4. The video camera according to claim 3, further comprising: stop control means for stopping the photometric value recalculation process using the already calculated value as the photometric value. 5. A video camera provided with an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the image signal, wherein the video signal output from the solid-state electronic image pickup device relates to a luminance signal. A component is extracted, and one of the components related to the extracted luminance signal in the imaging area is extracted.
Calculated partial photometric value on the basis of the component relating to the luminance signal obtained from the light receiving region of the solid-state electronic image sensing device corresponding to the part of the partial area, of the component relating to the luminance signal extracted the imaging area
And the average photometric value is calculated based on the component related to the luminance signal obtained from the light receiving area of the solid-state electronic image sensor corresponding to the entire area larger than the partial area , and the calculated partial photometric value is used for the partial photometric value. The first defined in
If judged whether falls within range, the range of exposure conditions the partial photometric value is the first when the said portion photometric value is determined not to fall to the first within range, the average A photometric value is defined for the average photometric value.
It said portion photometry so as to approach each second proper ranges
Value and at least one of the above average photometric values
A new exposure condition for the recalculation processing of the photometric value is determined, and the video signals output from the light receiving regions of the solid-state electronic image pickup device corresponding to the partial region and the entire region according to the determined new exposure condition. A photometric method for a video camera, in which the components related to the luminance signal are extracted from each of them, and the partial photometric value and the average photometric value are recalculated from the extracted components related to the luminance signal. The method according to claim 6, wherein said photometric value recalculation process, the partial light measurement value is repeated as the first within range and the average photometric value is determined to the second range <br/>囲内, the metering The video according to claim 5, wherein whether or not the value recalculation process is repeated a predetermined number of times is counted, and the photometric value recalculation process is stopped in response to counting the predetermined number of times and the already calculated value is set as the photometric value. Camera photometric method. 7. A video camera provided with an image pickup optical system including a solid-state electronic image pickup device for converting an incident light image into a video signal and outputting the image signal, wherein the video signal outputted from the solid-state electronic image pickup device relates to a luminance signal. extracting the components, of the components regarding the extracted luminance signal, the imaging area
Then, each photometric value is calculated based on the component related to the luminance signal obtained from the light receiving area of the solid-state electronic image pickup device corresponding to the plurality of areas, and all of the calculated plurality of photometric values fall within the plurality of predetermined areas. br /> determines whether falls within range that corresponds to each of the exposure conditions when the at least one photometric values of the plurality of photometric value is determined to be not within the corresponding on Kihan囲内, upper as determined by photometric values and non fit into corresponding on Kihan囲内approaches corresponding on Kihan囲内
Based on at least one of the multiple photometric values
A new exposure condition for light value recalculation processing is determined, and a luminance signal is output from a video signal output from a light receiving region of the solid-state electronic image pickup device corresponding to the plurality of predetermined regions according to the determined new exposure condition. Extract the components,
A photometric method for video cameras that recalculates the photometric value from the extracted components related to the luminance signal. The method according to claim 8, wherein said photometric value recalculation process, the corresponding upper Symbol
Repeat as photometric value is determined not fall within range is determined corresponding <br/> on Kihan囲内counts whether repeated a predetermined number of times the photometric value recalculation process, a predetermined number counting The photometric method of the video camera according to claim 7, wherein the photometric value recalculation process is stopped in response to the request, and the already calculated value is used as the photometric value.