JP3255436B2 - Imaging equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographing apparatus capable of photographing a still image.

[0002]

2. Description of the Related Art In the field of magnetic recording in recent years, demands for high-density recording have been increasing, and video tape recorders (V
TR), the running speed of the tape is reduced, and higher-density magnetic recording is performed.

[0003] When the running speed of the tape decreases, for example, when an audio signal is recorded using a fixed head, the relative speed cannot be increased so that the reproduced sound quality deteriorates. As one means for solving this problem, there is a method in which the length of a track operated by a rotary head is made longer than before, and an audio signal whose time axis is compressed is sequentially recorded in an extended portion thereof.

More specifically, in a rotary two-head helical scan type VTR, a magnetic tape is conventionally wound around a rotary cylinder by 180 degrees or more. In this method, a magnetic tape is wound around a rotary cylinder by (180 + θ) degrees or more. This is a method of recording an audio signal that is PCM-formed and time-axis-compressed in the wound “θ” portion.

FIG. 12 is a diagram showing a tape running system of such a VTR, and FIG. 12 is a diagram showing a recording locus on a magnetic tape by the VTR shown in FIG. Here, 1 is a magnetic tape, 2 is a rotary cylinder, 3 and 4 are heads mounted on the cylinder 2, 5 is a video signal recording area of a track formed on the tape 1, and 6 is a PCM audio signal recording area. Part. The video area 5 is traced by 180 degrees of the rotating cylinder 2 by the heads 3 and 4, and 6 is traced by θ of the rotating cylinder 2.

As described above, as an example of applying the method of recording a digital signal in another area while recording a video signal, it has been proposed to record a still image as a digital signal in the digital signal recording area. I have. If the image is a still image, it is possible to record all the information on the magnetic tape by scanning the PCM area a plurality of times. According to this method, not only can a still image be photographed using the same photographing apparatus and the same recording medium as for moving image photographing, but also, in a conventional VTR, the running of the tape is stopped and the video signal of the same track is reproduced. It is possible to obtain a higher quality still image than a still image.

[0007]

However, in the above conventional example, a still image is photographed by using a lens system originally designed for moving image photographing and its control system, and thus has the following disadvantages.

(1) In moving image shooting, even if the focus is slightly out of focus at the beginning of shooting, or if another subject is in focus in a near-far conflict state, it is resolved by, for example, slightly moving the camera. If you look at the playback image, you won't feel much discomfort.

[0009] However, in the case of still image shooting, if all frames are not shot with good focus, a low quality image will result.

(2) In a system originally designed for moving image photographing, automatic focusing is performed so that a user does not feel uncomfortable when moving image photographing is performed. Not necessarily.

(3) Most conventional consumer video camera systems do not have a function of adjusting the aperture or the like with priority to depth, and there is little need to have such a function. Was.

However, the lack of the depth priority adjustment function when photographing a still image means that a desired image cannot be obtained depending on the situation of the subject.

Accordingly, an object of the present invention is to provide
An object of the present invention is to provide a photographing apparatus configured to be able to take a good still image regardless of subject conditions.

[0014]

According to the present invention, there are provided a depth setting means for setting a plurality of depths by changing an aperture, and a plurality of still images at a plurality of depths set by the depth setting means by an image pickup device. A photographing apparatus comprising: a still image photographing means for photographing; and a control means for changing a gain of an output signal of the image sensor in accordance with an aperture changed by the depth setting means to set a plurality of depths. is there. Further, the present invention provides a motion detection unit configured to detect a motion of a subject, a depth setting unit that sets a plurality of depths by changing an aperture according to a detection result of the motion detection unit, and a depth setting unit. And a still image photographing means for photographing a plurality of still images at a plurality of depths.

[0015]

[0016]

[0017]

Embodiments of the present invention will be described below in detail.

Embodiment 1 FIG. 1 is a block diagram of a first embodiment to which the present invention is applied. In the figure, reference numeral 101 denotes a first group lens for performing focus adjustment, 102 denotes a variable power lens, 103 denotes a correction lens,
Reference numeral 04 denotes an aperture, 105 denotes a fixed fourth group lens, and 106 denotes an image sensor.

Reference numerals 107, 108, and 109 denote motors for focus adjustment, magnification adjustment, and aperture adjustment, respectively. 11
Reference numerals 0, 111, and 112 are drivers for driving the respective motors. Reference numerals 113, 114 and 115 are encoders for detecting the position of each lens and the aperture state.

Reference numeral 116 denotes an AGC (automatic gain control) circuit,
117 is a high-pass filter, 118 is a comparator for outputting a photometric value signal for adjusting the aperture, and 119 is a microprocessor. 120, 121, 122, and 123 are pull-up resistors. 124 is a zoom tele switch,
Reference numeral 125 denotes a zoom wide switch, and reference numeral 126 denotes a still image shooting release button.

Reference numeral 127 denotes a mode switch for switching between normal still image shooting (normal still image shooting mode) and still image shooting (bracket still image shooting mode) specific to this embodiment. Here, the bracket still image photographing mode refers to a photographing mode in which a plurality of images are recorded when a still image is photographed, and the photographing conditions are slightly changed every time the image is recorded.

129 is a still image memory, 130 is a memory control circuit, 131 is a recording circuit for converting the still image information read from the image memory 129 into a recordable video signal, 132 is a recording amplifier, 133 is a magnetic head, 134
Is a magnetic tape.

FIG. 2 is an external view showing the entire configuration of the embodiment shown in FIG. Here, 201 is the entire VTR according to the present embodiment, 202 is a zoom switch having the same function as the switches 124 and 125 shown in FIG. 1, 126 is a release button for photographing a still image (see FIG. 1),
A switch 127 selects between the above-described bracket still image shooting mode and the normal still image shooting mode (see FIG. 1).
It is. When the switch 127 is set to the “bracket” side, every time the release button 126 is pressed, the depth becomes a preset value, and still image shooting is performed in that state (see FIG. 3 for details). And will be described later in detail).

FIG. 3 is a work flowchart for executing the bracket still image shooting mode, and FIG. 4 is a recording state diagram of the magnetic tape 134 when the bracket still image shooting is performed.

An image memory 129 shown in FIG. 4 (see FIG. 1) uses a field memory or a frame memory for temporarily taking in a still image. That is, when the release button 126 is pressed, the image at that moment is taken into the image memory 129. The captured image signal is
As described in the conventional example, it is recorded in the PCM area. At this time, in order from the first still image, 401, 402, 40
3 will be recorded. This record contains
Usually, a period of ten to several tens of vertical synchronization periods is required.

Next, steps S301 to S301 shown in FIG.
According to S316, a processing procedure of bracket still image shooting according to the present embodiment will be described.

First, when execution of the flow is started in step S301 (hereinafter, the word "step" is omitted), counters m and n are reset to 1 and 0 in S302 and S303, respectively.

In step S304, it is determined whether or not a recording standby (Rec pause) state, which is a well-known function (not shown). If it is determined in S304 that the camera is in the Rec pause state, it is determined in S305A whether or not the release button 126 has been pressed. If not, the process returns to S305 assuming that the photographer has selected the depth, and waits. Continue. Also, if the release button 126 is pressed,
In step S307, the counter n is incremented by 1, the depth is fetched in step S308, and the depth is stored in the n-th storage area in step S309.

After storing the n depth states in this way,
When the Rec pause state is released in S304, S305
At B, it is determined whether or not the release button 126 has been pressed. While the release button 126 is not pressed, S31
In 0 and S311, the m-th depth is read out according to the order of the stored values stored in S309, and the aperture and the like are adjusted to that value.

After confirming that the release button 126 has been pressed in S305B, it is confirmed in S312 whether or not the aperture adjustment in S311 has been completed. If the adjustment has not been completed, the process returns to S305B to inhibit release. I do. Further, even if it is determined in step S312 that the aperture adjustment or the like is completed, in step S313, the information in the image memory 129 is not completely recorded from the output of the memory control circuit 130 and the recording circuit 131. Is determined not to be changed, the process returns to S305B to prohibit the release.

When the above condition is satisfied and writing of the image signal into the memory 129 is permitted, in S314,
The output of the image memory 129 is recorded on the magnetic tape 134 via the recording circuit 131, the recording amplifier, and the magnetic head 133. Then, the counter m is incremented by 1 in S315.

In step S316, it is determined whether or not all the set still images have been shot, based on the value of m. If the shooting has not been completed, the above operation is repeated from step S304. Prepare for shooting.

Embodiment 2 FIG. 5 is a flowchart showing a second embodiment of the present invention. In the present embodiment, shooting is performed by changing the depth by a predetermined depth width with respect to the state of the aperture or the like determined by the camera to be appropriate.

When the operation is started in S501 of FIG.
At 502, the value of the counter m is reset to 1.

Next, it is determined in step S503 whether or not the camera is in the Rec pause state. If the camera is in the Rec pause state, whether or not the release button has been pressed is detected in step S504. If the release button has not been pressed, the operation from step S503 is repeated, and when this button has been pressed, the processing from step S505 is executed to store the depth condition.

That is, in S505, the aperture value and the focal length under the photographing conditions automatically adjusted by the camera are read to calculate the depth, and the result is stored in the memory 1 in S506. Further, in S507, the depth calculated above is 1
A shallow depth is set, and the state of the aperture at this time is calculated and stored in the memory 2 in S507. In S508, S507
In the same manner as described above, a one-step deeper depth is calculated, and the state of the system at that time is stored in the memory 3.

As described above, the condition setting for the variable depth bracket shooting has been completed, so the flow returns to S503 to wait for the execution of the shooting.

After confirming that the Rec pause state has been released in step S503, the process waits for the release button to be pressed in step S509. If the button is pressed, the m-th depth setting information is read in S510, and the depth is adjusted in S511. In step S512, it is confirmed that the depth adjustment has been completed.
If it is confirmed that there is no problem even if the contents of the memory are rewritten in 512, shooting is performed on the memory in S514. Next, the value of the counter is incremented by 1 in S515, and it is determined in S516 whether or not shooting has been completed for all setting conditions. If the shooting has been completed, the process returns to S502, the counter is reset to 1, and the next bracket shooting command is waited. If not completed, the operation is repeated from S503.

With the above arrangement, it is possible to perform shooting at an appropriate depth for the aperture value automatically determined by the camera, and at deeper and shallower depths. Therefore, even if a plurality of subjects with different subject distances exist in one screen, the number of photographing failures due to the influence of perspective conflict is reduced.

Further, a still image at a plurality of depths can be automatically taken in the vicinity of an appropriate depth for a rapidly moving subject, so that a still image closest to the most aimed focus can be selected later.

Embodiment 3 FIG. 6 shows a third embodiment of the present invention. In the present embodiment, the depth is determined by detecting the movement of the subject.

First, a block for starting execution of the algorithm in this embodiment in step S601.

In step S602, the movement of the subject is detected by tracking or digital processing.

In step S603, the moving speed of the subject is detected.
In step S604, an optimal shutter speed is determined from the result of step S603 by referring to a table or the like.

The speed at which the subject moves is detected by the algorithm shown in FIG. 6, and the depth is determined by how much the subject moves during the time from when the shutter is pressed until the start of shooting a still image. By setting multiple depths at the center and shooting multiple still images,
Even if the selection in S604 is slightly incorrect, there is a high probability that a plurality of still images that have been captured at an appropriate depth are included.

Further, it is possible to change the nature of a still image, such as a relatively deep and a shallow subject, for one subject.

Further, in recent years, since the moving object prediction technology has been improved, some exposure times can be determined based on the prediction result.

Embodiment 4 FIG. 7 is a view for explaining a fourth embodiment of the present invention. In the present invention, when the depth is changed by changing the aperture, a satisfactory image may not be obtained due to an insufficient amount of exposure. Therefore, as shown in FIG. 7, the gain of the AGC circuit 116 (see FIG. 1) for amplifying the output signal of the image sensor is changed for the determined depth (aperture value), and a sufficient signal level is obtained. Like

In the manner described above, by controlling the aperture value, the depth is set to an advantageous condition for photographing, and the gain of the AGC circuit 116 is determined in advance in order to adjust the signal level which is increased or decreased by the aperture. , The AGC circuit can be quickly followed, and the effect of increasing or decreasing the exposure amount due to the aperture can be absorbed to perform photographing.

Embodiment 5 FIG. 8 is a flowchart for explaining a fifth embodiment of the present invention. In the present embodiment, the extension of the subject distance in the distance direction is detected in advance by the focusing means, and the depth is determined in a form corresponding to the extension.

In FIG. 8, when the process is started in S801, the bracket number counter S is reset in S802.

Next, in S803, it is detected whether or not it is a movie shooting (movie). If it is a movie, an operation for grasping the spread in the distance direction is performed only when the release button is pressed in S804. In this operation, first, after focusing on the subject in S805, the focus lens position is captured, and in S806, the subject distance is converted from the focus lens position.

In S807, the object distance of the S-th object is stored, and in S808, S is incremented by one. This is repeated a required number of times, and the depth at the time of shooting is determined based on the extension of the subject distance stored in S807.

Thereafter, when the still image shooting mode (still mode) is determined in S803, the stored object distance information is read in S810.

Next, grouping of subject distances is performed in S811. This grouping is used to change the depth of the subject, for example, in the vicinity of the center or all subjects when performing bracket shooting, and is selected by other means (not shown). If this group is divided into m, S
In step 812, depth calculation is performed sequentially from the first group in the same manner as in the first embodiment, and the depth is changed in step S813.
14. Still image shooting is performed in S815.

Finally, in S816, it is determined whether or not the photographing of all m groups has been completed, and if completed, a series of processing ends.

Embodiment 6 FIG. 9 shows a sixth embodiment of the present invention. In the present embodiment described below, a plurality of image memories are provided, and a plurality of still images are sequentially stored at a high speed in these image memories by pressing the release button once.

When a plurality of memories are used as in this embodiment, the configuration around the image memory is as shown in FIG. FIG.
0, 1001, 1002 and 1003 are image memories, 1004 is a switch for selecting these image memories,
Reference numeral 1005 denotes a switch for selecting the content of the image memory to be recorded, and reference numeral 1006 denotes a control circuit for controlling the switches 1004 and 1005. This switch control circuit 100
6 communicates with the microprocessor 119 and the recording circuit 131 because it is necessary to control the switches 1004 and 1005 in accordance with the timing of recording and release.

Next, a control procedure in this embodiment will be described with reference to FIG.

In S901 of FIG. 9, the aperture value encoder 1
The output of the F.15 is fetched, and based on the result, the microprocessor 119 converts it into an F value in S902.

Next, in S903, the depth B at that time is determined based on the result of S902.

In the next steps S904 and S905, the depths A and C are determined by one step before and after the above B (one step is an offset value determined by some method with respect to the reference depth).

While performing the processing in steps S901 to S905, the process waits until the release button 126 is pressed. It should be noted that the release button 126 is used during the moving image mode.
Is pressed at least once at S901 to S90.
5 needs to be performed.

When the release button 126 is pressed,
If it is determined in S305 that the camera is in the release state, the process proceeds to S90.
9 are performed. That is, S906 to S9
In each step 08, three still images exposed at the depths A, B, and C are obtained.

As described in the conventional example, a still image is recorded in a PCM area or the like on a magnetic tape at the same head / tape relative speed as when a moving image is shot. For example, if a still image is to be recorded in a recording area for a winding angle of 30 degrees as in the conventional example, a recording time of several to several tens of tracks, that is, several to several tens of vertical synchronization periods is required.

Considering the photo opportunity, this recording time is not negligible, and to solve this, a memory such as 1101, 1102, 1103 in FIG. 11 is prepared. If these memories are calculated for the number of bracketed shots or the recording time and the bracket interval, and are prepared for the minimum number of images that can be shot without increasing the bracket interval, shooting can be performed without missing a photo opportunity.

For example, if it takes two bracket intervals to record an image in the memory 1101 in the PCM area 1104, and if still images are recorded in 1102 and 1103 during that time, 4100 will be stored in 1101 upon completion of recording in 1104.
It becomes possible to store the still image information of the sheet. As described above, if the rotation of the three memories is performed, any number of bracket shootings can be performed successively.

With the above arrangement, it is possible to perform shooting at an appropriate depth for the aperture value automatically determined by the camera, and at deeper and shallower depths. Therefore, even if a plurality of subjects with different subject distances exist in one screen, the number of photographing failures due to the influence of perspective conflict is reduced. In addition, a still image at a plurality of depths can be automatically taken near an appropriate depth for a subject with a lot of movement, so that a still image closest to the target focus can be selected later.

If the reproduced images are re-input to the plurality of memories and subjected to digital processing, a still image having a wide dynamic range with respect to the contrast can be synthesized as a result.

[0070]

As described above, according to the present invention, it is possible to provide a photographing apparatus capable of photographing a good still image regardless of subject conditions.

[0071]

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is an external view showing the overall configuration of the present embodiment.

FIG. 3 is a flowchart illustrating a control procedure according to the present embodiment.

FIG. 4 is a diagram showing a recording area on a magnetic tape in the embodiment.

FIG. 5 is a flowchart showing a second embodiment of the present invention.

FIG. 6 is a flowchart showing a third embodiment of the present invention.

FIG. 7 is a flowchart showing a fourth embodiment of the present invention.

FIG. 8 is a flowchart showing a fifth embodiment of the present invention.

FIG. 9 is a flowchart showing a sixth embodiment of the present invention.

FIG. 10 is a block diagram showing a mode of use of a memory in the embodiment shown in FIG. 9;

FIG. 11 is a diagram showing a recording area on a magnetic tape when three image memories are used.

FIG. 12 is an explanatory diagram of a conventional technique.

FIG. 13 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 104 Aperture 106 Image sensor 115 Encoder 119 Microprocessor 126 Release button 127 Mode switch 129 Image memory 133 Magnetic head 134 Magnetic tape

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 5/235 G03B 7/08

Claims (2)

(57) [Claims] A depth setting unit that sets a plurality of depths by changing an aperture; a still image shooting unit that shoots a plurality of still images with an imaging device at a plurality of depths set by the depth setting unit; A photographing apparatus comprising: a control unit configured to change a gain of an output signal of the image sensor in accordance with an aperture changed by the depth setting unit to set a plurality of depths. 2. A motion detecting means for detecting a motion of a subject, a depth setting means for setting a plurality of depths by changing an aperture in accordance with a detection result of the motion detecting means, and setting by the depth setting means. A photographing device for photographing a plurality of still images at a plurality of depths.