JPH0738838A - Electronic still camera - Google Patents

Abstract

(57) [Abstract] [Purpose] In an electronic still camera, it is possible to select captured video information before recording on a medium. In an electronic still camera in which video information is recorded in a memory card 1 via a frame memory 25 for temporarily storing video information from an image sensor 21, a transfer control switch 31 interlocked with a shutter key and A video information reproducing system 40 is provided, the video information on the frame memory 25 is reproduced on the video display element 43, the photographer confirms the contents, and only the necessary video information is read from the frame memory 25 to the memory card 1. Transfer to.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic still camera.

[0002]

2. Description of the Related Art Conventionally, an electronic still camera in which information obtained from a solid-state image pickup device such as a two-dimensional CCD image sensor is electrically processed and recorded as a still image on a magnetic floppy disk or a solid-state memory. It has been known.

An electronic still camera basically uses an aperture and a shutter similar to those of a photographic camera using a silver salt film, and so-called AE automatically adjusts the aperture and the shutter based on the light amount of image pickup light. , Proper exposure is performed.

The still picture recorded on a predetermined medium is electronically reproduced by a still video player or reproduced as a hard copy by a still video printer (see Journal of the Television Society, Vol. 39, No. 9, etc.). ).

[0005]

As described above, in the conventional electronic still camera, the photographed still image is viewed by using a separate reproducing device, and the appropriateness of the exposure, the quality of the subject composition, etc. Will be confirmed after shooting. Therefore, when the photographed still image has an overexposure or underexposure or a poor composition, a problem arises in that the predetermined recording medium is not effectively used.

It is an object of the present invention to record before recording on a medium.
It is an object to provide an electronic still camera that allows selection of captured image information.

[0007]

In order to solve the above-mentioned problems, the electronic still camera according to the present invention has an image pickup device 21 and at least one screen from this image pickup device when the reference numerals of the embodiments described later correspond to each other. Storage device 25 for temporarily storing the video information of the above, video information reproducing means 40 including a video display device for reproducing and monitoring the video information stored in the storage device 25, and storage in the storage device 25. It is characterized in that it is provided with transfer control means 30 and 31 for controlling transfer of the generated video information to the storage medium.

[0008]

According to the present invention having the above structure, the memory element 25
The video information temporarily stored in the video display device 43 can be displayed on the video display element 43, the contents of the video information can be confirmed by the photographer, and the recorded video information can be selected before recording on the medium 1. Is possible.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an electronic still camera according to the present invention will be described below with reference to FIGS.

FIG. 1 shows the configuration of an embodiment of the present invention. In FIG. 1, the optical system represented by the lens 11 includes a diaphragm and an optical shutter (not shown) as described above. The exposure amount of the imaging light passing through the lens 11 is controlled by the control mechanism associated with each. Further, 20 is an image pickup system, and 30 is a system control circuit (microcomputer).

In this example, a CCD solid-state image pickup device 21 is mounted on the image pickup system 20. The image sensor 21 has an electronic shutter function 21sh for controlling the charge accumulation period and the like, and the color video signal output from the image sensor 21 is supplied to the analog processing circuit 22 and subjected to predetermined signal processing. In the A / D converter 23, for example, it is converted into a digital signal of 8 bits / 1 pixel sample and supplied to the digital processing circuit 24. The digital video signal for one screen from the processing circuit 24 is temporarily stored in the frame memory 25.

In this embodiment, a compression circuit 26c having a variable data compression ratio, such as the so-called JPEG method, is inserted between the frame memory 25 and the memory card 1, and the frame memory 25 is passed through the compression circuit 26c.
The above video information is transferred to the memory card 1 according to the transfer control described later.
Transferred to.

Further, in this example, a three-contact changeover switch 31 is provided which is interlocked with a two-stage shutter release key (not shown). This switch 31 is connected to the contact n when the shutter release key is not pressed,
It is connected to the contact m by half-pushing, and is connected to the contact r when it is pushed all the way in.

From the system control circuit 30, an exposure control signal Sex is supplied to the electronic shutter 21sh, and control signals Sca, Scb, Scc are supplied to the frame memory 25, the compression / expansion circuit 26, and the memory card 1, respectively. .

Further, in this embodiment, a reproducing system 40 is provided. The digital video signal from the frame memory 25 is supplied to the reproduction processing circuit 41, is subjected to predetermined signal processing, is returned to the original analog video signal in the D / A converter 42, and serves as an electronic viewfinder. , To the liquid crystal display element 43. Then, the video information read from the memory card 1 is passed through the expansion circuit 26e,
The image is supplied to the reproduction system 40 and reproduced, and the reproduced image is displayed on the liquid crystal display element 43.

Next, with reference to FIG. 2, the operation of selectively recording the picked-up image according to the embodiment of the present invention will be described.

In the initial state in which the two-stage shutter release key is not depressed, the changeover switch 31 has the contact n.
Connected to the side. Then, when the user half-presses the two-stage shutter release key, the switch 31 causes the contact m.
Switched to the side. When this is detected in step S1, the control signal Sex from the system control circuit 30 is output.
As a result, the electronic shutter 21sh is appropriately opened / closed to perform a predetermined exposure on the image sensor 21, and the frame memory 25 is set to the writing state for one frame period by the control signal Sca from the system control circuit 30. It

In this state, one frame of video information from the image pickup device 21 is written in the frame memory 25 through the analog processing circuit 22 to the digital processing circuit 24 (step S2). That is, the still image to be captured and recorded is captured in the frame memory.

In the next step S3, the frame memory 25 is brought into a read state by the control signal Sca from the system control circuit 30. And this memory 25
The video information read from the playback processing circuit 41, D /
It is supplied to the viewfinder 43 via the A converter 42 and reproduced on the screen.

Then, the user sees the reproduced image on the viewfinder 43 and selects whether the video information stored in the frame memory 25 is appropriate or not.

There is no problem in the reproduced image by the user,
When it is determined that the recording should be performed, the user can press the shutter release key down to the second stage. Then, the switch 31 is switched to the contact r side. When this is detected in step S4, the compression / expansion circuit 26 is set to the compression mode by the control signal Scb from the system control circuit 30, and the memory card 1 is set to the writing state by the control signal Scc.

In this state, the video information on the frame memory 25 is transferred to and recorded in the memory card 1 (step S5). Then, when the shutter release key is released, the movable contact of the switch 31 is returned to the n-contact side (step S6), and the still photography of one image ends.

If the user determines that there is any problem in the reproduced video, the user releases the shutter release key. Then, the movable contact of the switch 31 is returned to the contact n side, which is determined in step S7, and by the control signal Scc from the system control circuit 30,
The memory card 1 is set to the write-protected state, and the frame memory 25 is cleared by the control signal Sca (step S8).

As a result, the video information of the current shooting, which has some problems, is discarded, and the next still shooting is performed. If the image information of the shooting is overwritten in the frame memory 25 next time, the memory 25 need not be cleared in step S8.

As described above, in this embodiment, the video information temporarily stored in the frame memory 25 is reproduced on the screen of the viewfinder 43 so that before the final recording in the memory card 1, It is possible to check whether the exposure is appropriate or the composition of the subject, and it is possible to select the captured video information, so that the memory card 1 can be used effectively.

Further, in the above embodiment, 32 is a reproduction switch. The reproduction switch 32 is connected to the system control circuit 30, and when the switch 32 is operated, the mode control signal Scb from the control circuit 30 causes
The compression / expansion circuit 26 is set to the expansion mode, and the memory card 1 is set to the read state by the control signal Scc.
The video information compressed and recorded in the memory card 1 is
It is read out by this control, expanded by the circuit 26, and supplied to the reproduction system 40. Then, the reproduced image is displayed on the viewfinder 43.

In the above embodiment, the frame memory 25 has a capacity for one screen, but it is also possible to temporarily store video information for a plurality of screens.

Next, another embodiment of the electronic still camera according to the present invention will be described with reference to FIG.

The structure of another embodiment of the present invention is shown in FIG. In FIG. 3, parts corresponding to those in FIG. 1 above are denoted by the same reference numerals, and redundant description will be omitted.

In the embodiment of FIG. 3, between the digital processing circuit 24 of the image pickup system 20A and the frame memory 25,
The compression / expansion circuit 26 is inserted, and the digital processing circuit 2
One screen of digital video signal from 4 is compressed,
The digital video signal, which is temporarily stored in the frame memory 25 and is read from the frame memory 25 in a compressed state, is passed through the recording processing circuit 27 to the memory card 1
Recorded in.

Further, the digital video signal read out from the frame memory 25 in a compressed state is supplied to the reproducing system 40 through the expansion circuit 26e, and the electronic viewfinder 4 is operated.
A normal image is reproduced on the screen 3.

Then, the system control circuit 30 supplies the control signal Scd to the recording processing circuit 27 and the reproduction processing circuit 41. The rest of the configuration is the same as in FIG.

In the embodiment of FIG. 3 as well, similar to the embodiment of FIG. 1, the photographer can confirm the composition of the subject before the final recording on the memory card 1, and the frame It is possible to select the video information on the memory 25.

Also in this example, although not shown, a reproduction key is provided and the compressed and recorded signal is read from the memory card 1 by operating the reproduction key, and the reproduction signal is expanded. By supplying it to the reproduction processing circuit 41, reproduction processing can be performed.

[0035]

As described above, according to the present invention, a storage element for temporarily storing video information of at least one screen from the image pickup element is provided, and the video information is predetermined through the storage element. In the electronic still camera adapted to record on the recording medium, a transfer control switch and a video information reproducing system are provided, the video information on the storage element is reproduced on the video display element, and the photographer confirms the content. Since only the necessary video information is transferred from the storage element to the recording medium, it is possible to obtain an electronic still camera capable of selecting captured video information before recording on the medium.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of an electronic still camera according to the present invention.

FIG. 2 is a flow chart for explaining the operation of the embodiment of the present invention.

FIG. 3 is a block diagram showing the configuration of another embodiment of the present invention.

[Explanation of symbols]

20, 20A Imaging system 21 Solid-state imaging device 25 Frame memory 26 Data compression / expansion circuit 30 System control circuit (microcomputer) 31 Transfer control switch 40 Reproduction system 43 Liquid crystal display device (electronic viewfinder)

Claims (5)

[Claims] 1. An image pickup element, a storage element for temporarily storing at least one screen of image information from the image pickup element, and an image for reproducing and monitoring the image information stored in the storage element. An electronic still camera comprising: video information reproducing means including a display element; and transfer control means for controlling transfer of the video information stored in the storage element to a storage medium. 2. The electronic still camera according to claim 1, wherein the storage element can temporarily store video information for a plurality of screens. 3. The electronic still camera according to claim 1, wherein the video information from the storage element is data-compressed and transferred to the recording medium. 4. The electronic still camera according to claim 1, wherein the image information from the image pickup device is data-compressed and stored in the storage device. 5. The image information recorded on the recording medium is reproduced and displayed on the image display device.
The electronic still camera described in.