JP2667726B2 - Video camera - Google Patents

Description

The present invention relates to a video camera having a zoom mechanism.

[Related Art] A recent home video camera is provided with a zoom mechanism.

The zoom mechanism is configured such that, for example, when a zoom switch provided on a video camera body is pressed, a zoom lens position is moved by a zoom motor.

[Problems to be Solved by the Invention] When a user images a subject such as a container, when the subject is small, the user operates a zoom switch to enlarge the subject to a predetermined size and then image the subject.

In other words, when trying to capture an image of a subject in a certain size, the user must operate the zoom switch while checking the size of the subject in the viewfinder.
It was very troublesome.

Therefore, the present invention is such that the subject is automatically magnified to a certain size and imaged, and when the subject is present at a predetermined position on the screen, the subject is further magnified and imaged.

[Means for Solving the Problems] A video camera according to the present invention is a video camera having a zoom mechanism, wherein the zoom mechanism is operated based on position information of the subject, and the zoom means is configured to image the subject in a fixed size. A subject detection unit that detects that a subject is present at a predetermined location on the screen based on an image pickup signal obtained from the image pickup device; And an additional zoom means for further enlarging and picking up an image of a subject having a fixed size.

[Operation] In the present invention, it is possible to automatically magnify a subject to a certain size and take an image. Therefore, the user does not need to operate the zoom switch to enlarge the subject to a certain size.

Further, according to the present invention, when the subject is present at a predetermined position in the screen, for example, in the center, the subject is further magnified and imaged. Therefore, the subject can be imaged in a more magnified state. On the contrary, when the subject does not exist at a predetermined position in the screen, the subject is not further enlarged, and it is easy to catch the subject in the screen.

Embodiment An embodiment of the present invention will be described below with reference to FIG. This example is applied to a VTR with a built-in camera.

In FIG. 1, image light from a subject (not shown) is supplied to an image pickup device 2, for example, a CCD solid-state image pickup device via an image pickup lens 1.

The output signal of the image pickup device 2 is level-adjusted by the AGC circuit 3 and then supplied to the process circuit 4. From the process circuit 4, a luminance signal Y and a color difference signal (red difference signal R-
Y, blue difference signal BY) is output.

The luminance signal Y output from the process circuit 10 is supplied to the encoder 7 via the gamma correction circuit 5 and the amplifier 6. The color difference signals RY and BY output from the process circuit 4 are also supplied to the encoder 7.

In the encoder 7, a synchronization signal is added to the luminance signal Y, a burst signal is added to the color difference signal, color modulation is performed, and the carrier color signal C is formed.
Further, the luminance signal Y and the carrier color signal C are added to form a color video signal SV.

The color video signal SV formed by the encoder 7 is VTR
It is supplied to the section 8 as a recording signal. The operation of the VTR unit 8 is controlled by a controller 13 having a microcomputer (not shown) which will be described later.

Reference numeral 11 denotes a conventionally well-known focus sensor, and a subject position signal output from the focus sensor 11 is supplied to the focus motor 12 as a control signal.

The focus adjustment lens 1F that constitutes the imaging lens 1 is moved by the focus motor 12 based on the subject position signal. Thereby, the subject is automatically brought into focus.

The focus motor 12 is provided with a sensor (not shown) for detecting its rotation angle. The output signal of this sensor corresponds to the position of the focus adjustment lens 1F, that is, the position of the subject, and is supplied to the controller 13 as subject position information.

Reference numeral 14 denotes a zoom motor for moving the zoom lens 1Z constituting the imaging lens 1. The rotation of the zoom motor 14 is controlled by the controller 13.

A zoom sensor 15 detects the position of the zoom lens 1Z. The output signal of the zoom sensor 15 corresponds to the position of the zoom lens 1Z, that is, the zoom magnification, and is supplied to the controller 13 as zoom magnification information.

 Reference numeral 16 is a recording mode setting switch.

When the switch 16 is connected to the side, the normal recording mode is set. In the normal recording mode, the zoom motor 14 is not automatically controlled by the controller 13 at the time of recording. For example, even when the subject FL is small as shown in FIG. The second
In FIG. 3 and FIG. 3 described later, a broken line indicates a 70% frame of the screen.

When the switch 16 is connected to the side, the first zoom recording mode is set. In the first zoom recording mode, the zoom motor 14 is automatically controlled by the controller 13 at the time of recording, and for example, as shown in FIG.
When the FL is small, the subject FL is enlarged and imaged so as to fill approximately 70% of the frame as shown in FIG.

In this case, the subject is, for example, an adult, and the zoom magnification is calculated based on the subject position information supplied from the rotation angle sensor of the focus motor 12. That is, the zoom magnification is increased as the subject position is farther and the subject size is smaller. This also applies to the following second zoom recording mode.

When the subject originally exceeds the 70% frame of the screen, the image is captured as it is.

When the switch 16 is connected to the side, the second zoom recording mode is set. In this second zoom recording mode, the zoom motor 14 is automatically controlled by the controller 13 during recording, and as shown in FIG.
When the FL is small, the subject FL is enlarged and imaged so as to fill the screen as shown in FIG. In addition,
When the subject originally goes over the screen, the image is taken as it is.

Reference numeral 17 denotes a zoom switch. When the switch 17 is connected to the T side while the switch 16 is connected to the side, the controller 13 controls the zoom motor 14 to move the zoom lens 1Z in the TELE direction to sequentially increase the zoom magnification. Go. On the other hand, when the switch 17 is connected to the W side while the switch 16 is connected to the side, the zoom motor 1Z is
Moved in the DE direction, the zoom magnification is gradually reduced.

Further, the luminance signal Y added with the sync signal output from the encoder 7 is supplied to the sync separation circuit 18, and the separated vertical sync signal Vsync and horizontal sync signal Hsync are supplied to the controller 13 as reference sync signals. .

The luminance signal Y output from the encoder 7 is integrated by an integrator 19 and then supplied to one input terminal of a comparator 20. The reference voltage Vr is applied to the other input terminal of the comparator 20.
ef is supplied. The level of this reference voltage Vref is, for example,
Set to 70IRE.

The output signal of the integrator 19 is output from the comparator 20 to the reference voltage Vref.
A signal of high level "H", for example 5V, is output when the above is reached, and a signal of low level "L", for example 0V is output when the voltage is lower than the reference voltage Vref.

Generally, since the brightness of the FL of the subject is high, for example, FIG.
The output signal of the integrator 19 corresponding to the line a on the screen is
As shown in FIG. A, the portion corresponding to the subject FL is higher than the reference voltage Vref. Therefore, the output signal of the comparator 20 becomes as shown by the solid line in FIG. The broken line in FIG. 9B shows the output signal of the comparator 20 when the output signal of the integrator 19 is equal to or higher than the reference voltage Vref in the entire 70% frame range of the screen.

The output signal of the comparator 20 is supplied to the controller 13. The controller 13 calculates the ratio of the output signal of the comparator 20 to the high level "H" within the 70% frame of the screen.

When the output signal of the comparator 20 is at the high level "H" in the entire 70% frame of the screen, as shown by the alternate long and short dash line p in FIG. Ratio.

The controller 13 determines that the subject exists within the 70% frame of the screen when the final ratio is equal to or higher than the predetermined value, which is 70% or higher in this example (see the solid line q in FIG. 5). On the other hand, when the final ratio is smaller than the predetermined value (see the broken line r in the figure), it is determined that the subject does not exist within the 70% frame of the screen.

As described above, when the switch 16 is connected to the side, the subject FL is enlarged and imaged so as to fill the 70% frame of the screen during recording (see FIGS. 2B and 3A).
If the subject FL exists within the 70% frame of the screen and the subject position is not substantially infinity, the zoom magnification is further increased by a predetermined magnification, for example, 1.1 to 1.2 times. That is,
An additional zoom operation is performed. As a result, as shown in FIG. 3B, the subject FL screen is imaged larger than the 70% frame. To determine whether the subject position is almost infinite,
This is performed based on subject position information from a rotation angle sensor to which the focus motor 12 is attached.

When the subject FL no longer exists within the 70% frame of the screen or when the subject position becomes substantially infinite, the additional zoom operation is canceled and the size of the subject FL is returned to the original size (FIG. 2). B and FIG. 3A).

Reference numeral 21 denotes a recording switch, and this switch 21 is connected to the controller 13.

In the above configuration, the operation at the time of recording is performed according to the flowchart of FIG.

In the figure, when the recording switch 21 is turned on, it is determined in step 31 whether or not the focus has been stabilized based on the subject position information.

When the focus is stabilized, it is determined in step 32 whether or not the zoom recording mode is set. If the switch 16 is connected to the normal recording mode, the
Then, the recording operation of the VTR unit 8 is started.

When the switch 16 is connected to the side or the side and the zoom recording mode is set, in step 33, the zoom magnification is calculated based on the subject information, and after that, the zoom motor 14 is controlled and the zoom operation is performed. (See FIGS. 2B and 2C) In step 34, the recording operation of the VTR unit 8 is started.

Next, in step 35, it is determined whether or not the current mode is the first zoom recording mode. When the switch 16 is connected to the side or the side and is not in the first zoom recording mode,
Proceed to step 42.

When the switch 16 is connected to the side and is in the first zoom recording mode, it is determined in step 36 whether or not the subject position is substantially infinite based on the subject position information. If it is determined that the size is not substantially infinite, step 37
It is determined whether or not the subject is within the 70% frame of the screen. If it is determined that it is within the 70% frame, it is determined in step 38 whether the additional zoom operation has already been performed. When the additional zoom operation is being performed,
Proceeding to step 42, if the additional zoom operation has not been performed, the additional zoom operation is performed in step 39,
After the subject FL is further enlarged, the process proceeds to step 42.

When it is determined in step 36 that the subject position is substantially infinite, and when it is determined in step 37 that the subject is not within the 70% frame, in step 40, the additional zoom operation has already been performed. Is determined. When the additional zoom operation is not performed, the process proceeds to step 42, and when the additional zoom operation is performed, the process proceeds to step 41 after the additional zoom operation is canceled in step 41.
Proceed to 42.

In step 42, it is determined whether the recording switch 21 is off. If the recording switch 21 is not off,
Returning to 35, the same operation as described above is repeated.

If the recording switch 21 is off, step 43
Then, the recording in the VTR section 8 is terminated and ends.

As described above, according to the present example, by turning on the recording switch 21 with the switch 16 as the side or the side, the zoom motor is controlled by the controller 13 based on the subject position information.
14 is controlled, and the subject FL is automatically enlarged to a certain size, imaged, and recorded.

Therefore, the user does not need to perform the troublesome operation of enlarging the subject FL to a certain size by operating the zoom switch 17 as in the conventional case, which is convenient.

Further, since the additional zoom operation is performed in the second zoom recording mode, the subject FL can be imaged with a larger magnification. When the subject FL does not exist within the 70% frame, the additional zoom operation is canceled.
It becomes easier to catch FL again.

Note that the 70% frame of the screen set in the above embodiment is an example, and it is a matter of course that the present invention is not limited to this. The size of the frame may be arbitrarily set by the user without being described above.

Further, although the above-described embodiment applies the present invention to the camera-integrated VTR, the present invention can be applied to other video cameras as well.

[Effects of the Invention] As described above, according to the present invention, a subject can be automatically enlarged to a certain size and imaged, and the user can operate the zoom switch to obtain a certain size of the subject. This eliminates the need for an enlargement operation, and is easy to use.

Further, according to the present invention, when the subject is present at a predetermined position in the screen, the subject is further magnified and imaged, so that the subject can be imaged in a more magnified state. Conversely, when the subject does not exist at a predetermined position in the screen, the subject is not further enlarged,
The subject can be easily captured on the screen.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram for explaining each recording mode, FIG. 3 is a diagram for explaining an additional zoom operation, and FIG. 4 is a diagram for showing a comparator. FIG. 5 is a diagram for explaining the subject position determination, and FIG. 6 is a flowchart showing the recording operation. 1 ... imaging lens 1F ... focus adjustment lens 1Z ... zoom lens 2 ... imaging element 4 ... process circuit 7 ... encoder 8 ... VTR section 11 ... focus sensor 12 ... focus motor 13 ... controller 14 ...... Zoom motor 15 ...... Zoom sensor 16 ...... Recording mode switch 17 ...... Zoom switch 19 ...... Integrator 20 ...... Comparator 21 ...... Recording switch

Claims (1)

(57) [Claims] 1. A video camera having a zoom mechanism, wherein the zoom mechanism is operated based on the position information of the subject to image the subject in a fixed size, and the subject is obtained from an image pickup signal obtained from an image pickup device. Subject detecting means for detecting that the subject is present at a predetermined location on the screen, and an additional zoom means for further enlarging and imaging the subject of a certain size by the zoom means when the subject is present at the predetermined location on the screen. A video camera comprising: