JP2000278578A - Electronic still camera - Google Patents

Abstract

(57) [Summary] [PROBLEMS] In an electronic still camera which displays by a display means having a smaller number of pixels than the number of pixels of a recorded image signal at the time of reproduction, whether the focus of the display image is good or not, or A means is provided for more reliably determining whether the focus position is good or bad. SOLUTION: At the time of photographing, focal point position information indicating a focused position in a photographed image area is created in an image control unit 4, and the focal point information is reproducible in association with an image signal. The focal position information is reproduced together with the recorded image signal during reproduction, and the position indicated by the focal position information is displayed on the reproduced image displayed on the display means 3 to confirm the focus position. However, the quality of the focus can be determined more reliably by enlarging and displaying an image near the focal position.

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 for recording a subject image in a predetermined area as an image signal, and more particularly, to displaying an input image signal or a recorded image signal on a display device. Alternatively, when the number of pixels that can be displayed by the display device is very small with respect to the number of pixels of the recording image signal, whether the focus of the display image is good or bad,
Alternatively, there is provided means for more reliably determining the quality of the focal position in the display image.

[0002]

2. Description of the Related Art Generally, an electronic still camera is provided with a liquid crystal display device for displaying an input image or a recorded image, and the number of displayable pixels of the liquid crystal display device is determined by the number of pixels of the recorded image. Very few compared to. For example, if the solid-state imaging device, which is an image input device of an electronic still camera, has about 1.3 million pixels, the number of pixels of a recorded image is generally 1280 in the horizontal direction and 102 in the vertical direction.
There are four pixels. On the other hand, if the number of displayable pixels of the liquid crystal display device is about 80,000 pixels, it becomes 320 pixels in the horizontal direction and 240 pixels in the vertical direction. In addition, since the electronic still camera displays the entire image when displaying the input image or the recorded image, it is necessary to display the input image after performing a thinning process. One in one,
It will be thinned out by a factor of 4.27 in the vertical direction.

An outline of a conventional electronic still camera will be described below with reference to FIG. FIG. 6 shows a schematic block diagram of a conventional electronic still camera. Reference numeral 9 denotes an optical system for forming an image of a subject on the surface of a solid-state image sensor, and reference numeral 10 denotes an image signal (optical image) of the formed subject image (optical image). signal)
, An A / D converter for converting an analog signal obtained from the solid-state imaging device into a digital signal, and 12 for correcting an image signal obtained from the A / D converter and for luminance and color difference. Alternatively, an input image processing unit for performing a process of converting the image into an RGB image signal, an image control memory 13 used for temporarily storing an input image and compressing / expanding an image, and 14 transmitting various external commands The control switch group 15 is the control switch group 14
An interface unit for transmitting a signal from the CPU 16 to the CPU 16. The CPU 16 performs various controls inside the electronic still camera, 17 is a display image control unit that performs a thinning process of an input image or a recorded image, 18 is a display image control memory that stores a thinned image, Reference numeral 19 denotes a liquid crystal display unit for displaying an image in the display image control memory;
Is an image compression unit for compressing an input image or decompressing a recorded image, 21 is an internal bus for transferring image signals and other control data between blocks, and 22 is for data transfer between the image recording unit and the internal bus. Section 23 is an image recording section for storing image signals.

The operation of the electronic still camera configured as described above will be described below. When recording an input image, a subject image is formed on a solid-state imaging device 10 through an optical system 9 in FIG. 6 and processed by an A / D converter 11 and an input signal processing unit 12, and then an RGB signal or It becomes a luminance / color difference signal, and temporarily
Stored in AM13. The image data stored in the RAM 13 is again sent to the display image control unit 17 through the internal bus 21, subjected to a thinning process, transferred to the RAM 18, and displayed on the liquid crystal display unit 19. The image data stored in the RAM 13 passes through the internal bus 21 and is subjected to image compression calculation by the image compression unit 20 to reduce the amount of data.
The image data is again sent to the interface unit 22 through the internal bus 21 and added to the image attached information, and then recorded on the recording medium by the image recording unit 23. This series of operations is realized by the CPU 16 responding to the command sent from the control switch group 14 performing all control. Although not described in the above description, the flow of the CPU operation command starts from focusing of the optical system and continues until it is recorded on the recording medium.

In order to confirm the reproduction of a recorded image,
The image data recorded on the recording medium is read from the image recording unit 23, sent to the image compression unit 20 via the interface unit 22 and the internal bus 21, and the decompression calculation of the compressed image data is performed. It is temporarily stored in the RAM 13 via the internal bus 21. The image data stored in the RAM 13 is sent again to the display image control unit 17 through the internal bus 21, and after the thinning process is performed,
18 and displayed on the liquid crystal display unit 19. By this reproduction confirmation operation, the already recorded image data can be confirmed, and it is possible to determine whether or not to erase the recorded data. As described above, this series of operations is performed by the CPU 16 responding to a command sent from the control switch group 14.
Is realized by performing all the controls.

[0006] All the displays in the above electronic still camera are subjected to thinning-out processing in order to display the entire image. For example, if thinning-out is performed to a quarter in both the vertical and horizontal directions, the thinning-out processing is generally performed in the vertical direction. A method of taking an average value of 16 pixels of 4 pixels and 4 pixels in the horizontal direction and allocating one pixel is adopted.

[0007]

However, in the conventional electronic still camera, when displaying an image, a means for confirming whether or not the image is in focus is not considered.
The liquid crystal display is based on the assumption that the entire image is displayed, and a thinning process is performed. For this reason, the first problem is that it is not possible to confirm from the image displayed on the liquid crystal whether the image is in focus due to the deterioration of the high frequency component due to the thinning process. There is also a second problem that it is not possible to confirm where the focus has been set.

[0008]

In order to solve the above-mentioned problems, in an electronic still camera according to the present invention, when focusing is performed, a position of an object to be focused is searched for, and a focal position in an imaging screen is focused. It is configured to be recorded together with an image as position information. When displaying an image, a function of enlarging and displaying not only the entire image but also an image in a certain area centered on the focused position based on the focal position information is added, so that the first image is displayed. To solve the problem. Further, the second problem is not solved by adding a function for indicating where in the entire image is focused based on the focal position information with a predetermined mark on the entire image. is there.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the first aspect of the present invention, a subject image in a predetermined area is recorded as an image signal, and at the time of reproduction, the recorded image signal is recorded. In an electronic still camera displaying by a display unit having a smaller number of pixels than the number of pixels, at the time of recording, focus position information indicating a focused position in the area is created,
An electronic still camera characterized in that the focus position information is recorded in a reproducible manner in association with the image signal, and a focus position indicating a focused position in the shooting region together with the recorded image signal. Since the information is recorded, even at the time of reproduction, even in the display means having a small number of pixels, it is possible to confirm the focal position in the reproduced image by using the focal position information and to enlarge and display an image near the focal position. It is possible to more reliably determine the quality of focusing.

According to a second aspect of the present invention, a subject image in a predetermined area is recorded as an image signal, and during reproduction, the recorded image signal is smaller than the number of pixels of the recorded image signal. In an electronic still camera displaying by a display unit of the number of pixels, at the time of recording, focus position information indicating a focused position in the area is created, and the focus position information is recorded in a reproducible manner in association with the image signal. In addition, at the time of reproduction, the focal position information is reproduced together with the recorded image signal, and a predetermined range including the position indicated by the focal position information is enlarged and displayed on the display means. Since this is a still camera, it records the recorded image signal and the focal position information indicating the focused position in the shooting area. In even, based on the focus position information, the determination the quality of the focus due to enlarge the image in the vicinity of the focus position in which allows more reliably.

According to a third aspect of the present invention, an image of a subject in a predetermined area is recorded as an image signal, and during reproduction, the recorded image signal is smaller than the number of pixels of the recorded image signal. In an electronic still camera displaying by a display unit of the number of pixels, at the time of recording, focus position information indicating a focused position in the area is created, and the focus position information can be reproduced in association with the image signal. An electronic still camera which records the focal position information together with the recorded image signal during reproduction and displays the position indicated by the focal position information on a reproduced image displayed on the display means. At the time of reproduction, even in the display means having a small number of pixels, the position indicated by the focal position information is displayed on the reproduced image displayed on the display means, so that the reproduced image Confirmation of definitive focus position is intended to perform more reliably. (Embodiment) An embodiment of the present invention described in claims 1 to 3 of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic block diagram of an electronic still camera according to an embodiment of the present invention.
It comprises an optical system 1, a solid-state imaging device 2, a liquid crystal display unit 3, an image control unit 4, an image memory 5, a shutter switch 6, a display changeover switch 7, and a position search unit 8. The basic configuration of recording, reproducing, and displaying an image is the same as the detailed block diagram of the conventional electronic still camera shown in FIG. 6, and the operation of the electronic still camera according to the embodiment of the present invention will be described. FIG. 6 is also referred to. FIG. 2 shows a control flow of the electronic still camera according to the embodiment of the present invention.

In FIG. 1, a command is received from a shutter switch 6 and an object is formed on the surface of a solid-state image sensor 2 through an optical system 1 to form an object image (optical image).
Is processed by the image processing unit 4 and then written into the image memory 5. After the image data written in the image memory 5 is processed again by the image processing unit 4, the image data is displayed on the liquid crystal display unit 3, the image data written in the image memory is subjected to a compression process, and recorded on another recording medium. I do. This series of basic operations are operations at the time of recording in the above-described conventional electronic still camera. However, in the present embodiment,
At this time, the shutter switch 6 for issuing a recording command is operated in two steps. In the first step, the focus is adjusted by lightly touching or lightly pressing the shutter switch, and an image for later-described comparison is formed at the focused position. Record
In the second stage, a normal image for storage is recorded by depressing a shutter switch without newly performing focus adjustment.

Then, by comparing the recorded image when the first-stage shutter switch is pressed and the image when the second-stage shutter switch is pressed, the photographing area when the first-stage shutter switch 6 is pressed is obtained. For the second
Focus position information indicating a focus position on a photographed image when the second-stage shutter switch is pressed obtained by detecting motion information indicating how much the photographing area has moved when the shutter switch of the second stage is pressed. Is created and recorded so as to be reproducible in association with an image signal. The motion detection can be obtained by calculating a difference value between two pixels including peripheral pixels.

The operation of the electronic still camera according to the present embodiment when recording an image will be described in more detail with reference to FIGS. 1, 2 and 6. When the electronic still camera is turned on and enters the recording mode, the entire image of the image input from the lens is normally displayed on the liquid crystal display unit. At this time, as shown in the flow of FIG.
The shutter switch (shutter switch 6 in FIG. 1) in the control switch group 14 has not been pressed yet, and as a control, first, the image data stored in the solid-state imaging device 10 through the optical system 9 by the instruction of the CPU 16 is A / A. After being converted into a digital signal by the D converter 11, the input processor 12 performs image correction, and transfers the image data to the display controller 17 via the internal bus 21. The image data transferred at this time is proportional to the number of pixels of the solid-state imaging device 10. For example, if the solid-state imaging device has a pixel number of 1280 × 960, the image data is RGB data of 8 bits each of 1280.
When the liquid crystal of the liquid crystal display section has a 320 × 240 pixel display, it is necessary to perform a process of thinning out the image data by a factor of four in both the vertical and horizontal directions. At 17, a thinning-out process is performed, and 320 × 240 pixels are written into the memory 18. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed. At this time, the image displayed on the liquid crystal is the entire image of the image input through the lens, and a series of these operations is performed when the shutter switch (the shutter switch 6 in FIG. 1) of the switch group 14 is pressed. Until it is done.

As a first-stage operation, a first focus adjustment command is issued by touching or lightly pressing the two-stage shutter switch 6 in the present embodiment, and the optical system 9 is operated and determined in advance. Location,
For example, the focus is adjusted so that the center of the shooting area is focused. Next, the image data stored in the solid-state imaging device 10 is transferred from the internal bus 21 to the area I of the memory 13. Next, in response to an instruction from the CPU 16, the memory 13
A part of the image data stored in the area I of the
The image data is transferred to the display system control unit 17 through the interface, converted into a display image, and then transferred to the memory 18. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed. At this time, for example, if the image captured by the solid-state imaging device is 1280 × 960 pixels and the liquid crystal display is 320 × 240 pixels, the display system control unit 17 performs a 1/4 thinning process in both the vertical and horizontal directions and displays the image. It will be. Further, the adjusted focus is fixed and held as long as the first focus adjustment command is not canceled. Next, as the operation of the second stage, when the two-stage shutter switch 6 is pressed, a second recording command is issued, and at that time, the focus is not adjusted again, and the image is stored in the solid-state imaging device 10 at that time. The obtained image data is transferred from the internal bus 21 to the area II of the memory 13. Memory 1
3 is stored in the internal bus 2
1 is transferred to the display system control unit 17 again. At this time, the data is similarly transferred to the memory 18 after the thinning process is performed to a quarter in both the vertical and horizontal directions. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed. At this time, the image displayed on the liquid crystal is the entire image input through the lens. Here, the image signals of the area I and the area II of the memory 13 are compared, and the first
Detects the movement information of how much the shooting area has moved from the position where the step shutter switch is pressed to the position where the second step shutter switch is pressed, and a photographed image when the second step shutter switch obtained by this movement information is pressed. Create focal position information indicating the focal position on the top,
It is configured to record.

Further, the image data recorded again in the area II of the RAM 13 is transferred to the image compression section 20 in accordance with an instruction of the CPU 16 and subjected to image compression calculation processing to reduce the data amount. Finally, the compressed and reduced data and position information are transferred to the image recording unit 23 through the internal bus 21 and the interface 22, and recorded on a recording medium provided in the image recording unit 23.

The operation from when the shutter switch 6 is pressed and the first and second commands are issued to when recording is performed on the recording medium ends, and the electronic still camera waits for a new command. Return to the environment. Also here
The control flows of A and B shown in FIG. 2 may be exchanged, and the control flow of B may be realized as a form included in A.

Next, the operation at the time of reproduction will be described with reference to FIG. 1, FIG. 3, FIG. 4, and FIG. When the electronic still camera is turned on and enters the playback mode, normally nothing is displayed on the liquid crystal display unit, or one of the already recorded image data is displayed. The purpose of reproducing the recorded image is to confirm whether the recorded image is beautifully taken or to determine whether to save or delete the recorded image. Therefore, in the present embodiment, assuming that the user of the electronic still camera has finished selecting an image to be judged, the following operation will be described.

When an already recorded image to be reproduced in the reproduction mode is selected, the image data is called from a recording medium provided in the image recording section 23 by an instruction of the CPU 16, and the interface 22 and the internal bus 21 are read. Is transferred to the image compression unit 20 through In the image compression unit 20, since the transmitted image data is data subjected to image compression processing, the image data is subjected to decompression processing, returned to data in a reproducible format, and decompressed to the memory 13 through the internal bus 21. Transfer data.

Next, the decompressed image data stored in the memory 13 is transferred to the display system controller 17 through the internal bus 21. The image data transferred at this time has the size of the recorded image. For example, if the image data is a recorded image having 1280 × 960 pixels, the image data is 8 bits for each of RGB or 1280 × 960 pixels. 960
In the case where the liquid crystal of the liquid crystal display unit has a 320 × 240 pixel display, the image data needs to be thinned out to a quarter in both the vertical and horizontal directions as in the recording mode. A thinning process is performed in the display control unit 17, and 320 × 240 pixels are written into the memory 18. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed. At this time, the image displayed on the liquid crystal becomes the whole image of the recorded image, and the selected image is reproduced.

Here, when the user of the electronic still camera tries to enlarge the image for the purpose of checking the focus, for example,
A command to enlarge an image is transmitted to the CPU 16 through the interface 15 from the display changeover switch 7 of FIG. 1 which is one of the control switches 14. Next, the CPU 16
From the recording medium provided in the image recording unit 23, the focus position information of the corresponding image is called, and the image data at the focused position is transferred from the memory 13 through the internal bus 21 based on the focus position information. Then, the data is transferred to the display system control unit 17, converted into a display image, and then transferred to the memory 18. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed.
At this time, as shown in FIG. 5, a recorded image area is defined as an area A, and an image area centered on a focused position to be transferred to the display system control unit 17 is defined as an area B. The image is 1280 × 960 pixels, the liquid crystal display is 320 × 240 pixels, and the display system control unit captures 64 images.
If the number of pixels is 0 × 480 pixels, the display control unit 17 performs a thinning process of half in both the vertical and horizontal directions, and the area B is displayed on the entire liquid crystal screen. As a result, the above-described series of operations from the issuance of the enlargement command to the display of the enlarged image makes it possible to confirm the focus of the recorded image more reliably.

Next, for the currently reproduced image whose focus has been confirmed, a determination is made as to whether to save or delete the record. If it is determined that the image is to be stored, no action is taken and it is determined to be deleted. In this case, a command from the CPU 16 is transmitted to the image recording unit 23 by a predetermined operation, and the recorded image data is deleted. When the above operation is completed, the process returns to the beginning of the image reproduction mode again.

In this embodiment, the size of the image to be enlarged and displayed is 640 × 480, and the number of liquid crystal display pixels is three.
The size is set to 20 × 240. However, if control is performed so that the size of the image to be enlarged and displayed is equal to the size of the image that can be displayed on the liquid crystal, the focus can be confirmed more reliably.

Further, in the present embodiment, the recording data storage determination processing is performed immediately after the image enlargement processing. However, after the image enlargement processing, a processing for canceling the enlargement switch may be inserted. The flow and the flow of FIG. 3A are inserted. In FIG. 3, after all the operations are completed, the operation returns to the operation of transferring the image data of the recording unit to the compression unit. However, it is more natural to return to the operation of selecting a new image. Mode.

Next, an embodiment of the present invention described in claim 3 of the present invention will be described with reference to FIGS. 1, 4 and 6. When the electronic still camera is turned on and enters the playback mode, normally nothing is displayed on the liquid crystal display unit, or one of the already recorded image data is displayed. The purpose of reproducing the recorded image is to confirm whether the recorded image is beautifully taken or to determine whether to save or delete the recorded image. Therefore, in the present embodiment, assuming that the user of the electronic still camera has finished selecting an image to be judged, the following operation will be described.

When an already recorded image to be reproduced in the reproduction mode is selected, the image data is called out from the recording medium provided in the image recording section 23 by the instruction of the CPU 16, and the interface 22 and the internal bus 21 are read. Is transferred to the image compression unit 20 through In the image compression unit 20, since the transmitted image data is data subjected to image compression processing, the image data is subjected to decompression processing, returned to data in a reproducible format, and decompressed to the memory 13 through the internal bus 21. Transfer data.

Next, the decompressed image data stored in the memory 13 is transferred to the display controller 17 through the internal bus 21. The image data transferred at this time has the size of the recorded image. For example, if the image data is a recorded image having 1280 × 960 pixels, the image data is 8 bits for each RGB or 1280 × 960 data in the form of luminance and color difference. In the case where the liquid crystal of the liquid crystal display unit has a 320 × 240 pixel display, the image data needs to be thinned out to a quarter in both the vertical and horizontal directions as in the recording mode. A thinning process is performed in the display system control unit 17 to make 320 × 240 pixels and the memory 1
8 is written. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed.
At this time, the image displayed on the liquid crystal becomes the whole image of the recorded image, and the selected image is reproduced.

Here, when the user of the electronic still camera attempts to display a mark for confirming the focus position on the image, the mark is obtained by operating the display changeover switch 7 shown in FIG. The received focus position confirmation command is transmitted to the CPU 16 through the interface 15. Next, in response to an instruction from the CPU 16, focal position information is called from a recording medium provided in the image recording unit 23, and based on the focal position information, a signal in the memory 13 is used, for example, in such a form as to surround the focused position. The mark is overwritten, the image data overwritten with the mark is transferred to the display system control unit 17 through the internal bus 21, converted into a display image, and then transferred to the memory 18. Then, the written image data is repeatedly transferred to the liquid crystal display unit 19, and the liquid crystal display is performed.
Thus, after the focus position confirmation command is issued, a mark indicating the focused position is added, so that it is possible to surely confirm where in the entire image the image is focused.

Next, for the currently reproduced image whose focus has been confirmed, a determination is made as to whether to save or delete the record. If it is determined that the image is to be stored, no action is taken, and it is determined to be deleted. In this case, a command from the CPU 16 is transmitted to the image recording unit 23, and the recorded image data is deleted.

When the above operation is completed, the process returns to the beginning of the image reproduction mode. Further, in this embodiment, the storage data storage determination processing is performed immediately after the focus position confirmation. However, after the focus position confirmation, a cancellation processing of the focus position confirmation switch may be performed. And the flow of FIG. 4A is inserted. FIG. 4
In this example, after all operations are completed, the operation returns to the operation of transferring the image data of the recording unit to the compression unit. However, returning to the operation of selecting a new image is a more natural reproduction mode.

The above two reproduction modes may be used not only alone but also in combination. In other words, the same effect can be obtained by a method such as confirming the focal position with a mark at the time of image reproduction and then enlarging and displaying the image at the confirmed position.

[0032]

As described above, according to the present invention, when the image is recorded, the focused position is recorded, so that when the image is reproduced and displayed, the focused position is enlarged and the image is displayed. Alternatively, by indicating the position where the entire image is focused by a predetermined mark, it is possible to more reliably confirm whether the recorded image is in focus or where it is in focus.

[Brief description of the drawings]

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

FIG. 2 is a control flow chart during recording in the electronic still camera.

FIG. 3 is a control flow chart at the time of reproduction in the electronic still camera.

FIG. 4 is a control flowchart at the time of another reproduction in the electronic still camera.

FIG. 5 is a view showing an example of an image area displayed on the display device of the electronic still camera.

FIG. 6 is a schematic block diagram of a conventional electronic still camera.

[Explanation of symbols]

 Reference Signs List 1 optical system 2 solid-state imaging device 3 display device 4 image control unit 5 image memory 6 shutter switch 7 display changeover switch 8 position search unit 9 optical system 10 solid-state imaging device 11 A / D conversion circuit 12 input signal processing circuit 13 image recording memory Reference Signs List 14 control switch group 15 interface circuit 16 CPU circuit 17 display image signal processing circuit 18 image display memory 19 image display element 20 image compression calculation circuit 21 internal bus 22 interface circuit 23 recording circuit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor, Hirokatsu Mizuki 1-8, Koshinmachi, Takamatsu City, Kagawa Prefecture Matsushita Hisashi Denshi Kogyo Co., Ltd. F-term (reference) 5C022 AA13 AB22 AB68 AC03 AC52 AC69

Claims (3)

[Claims] An electronic still which records a subject image in a predetermined area as an image signal and displays the recorded image signal by a display means having a smaller number of pixels than the number of pixels of the recorded image signal during reproduction. An electronic still camera, wherein, at the time of recording, focus position information indicating a focused position in the area is created, and the focus position information is recorded in a reproducible manner in association with the image signal. . 2. An electronic still which records a subject image in a predetermined area as an image signal and displays the recorded image signal by a display means having a smaller number of pixels than the recorded image signal during reproduction. In the camera, at the time of recording, focus position information indicating a focused position in the area is created, and the focus position information is recorded so as to be reproducible in association with the image signal, and at the time of reproduction, the recording is performed. An electronic still camera which reproduces the focal position information together with an image signal, enlarges a predetermined range including the position indicated by the focal position information, and displays the enlarged range on the display means. 3. An electronic still which records a subject image in a predetermined area as an image signal and displays the recorded image signal by a display means having a smaller number of pixels than the recorded image signal during reproduction. In the camera, at the time of recording, focus position information indicating a focused position in the area is created, and the focus position information is recorded so as to be reproducible in association with the image signal, and at the time of reproduction, the recording is performed. An electronic still camera which reproduces the focal position information together with an image signal and displays a position indicated by the focal position information on a reproduced image displayed on the display means.