JPH11196325A - Photographing device, photographing system, photographing method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photographing device and a method capable of easily avoiding an adverse effect of flash lighting. SOLUTION: First and second flash lighting parts 1, 2 are oppositely arranged around a photographing lens 3. A picture free from shadows due to flash lighting is obtained as follows. Namely, the 1st flash lighting part 1 is actuated, a 1st picture is photographed and its data are stored in a memory. Then, the 2nd flash lighting part 2 is actuated, a 2nd image is photographed and its data are stored in the memory. Then, operations for reading the 1st and 2nd image data from the memory, comparing their corresponding pixel data with each other and storing the data having larger luminance in the memory are executed for all pixel data to obtain the data of an image free from shadows due to flash lighting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographing device such as a digital camera, a photographing system, a photographing method, and a storage medium storing a program for realizing the photographing method, and more particularly to photographing using a flash.

[0002]

2. Description of the Related Art Heretofore, in a camera using a silver halide film, when taking a flash, the shadow of the flash light may come out of an unexpected place to break the image. For example, in portrait photography with a wall on the back, a shadow appears on the wall, resulting in an annoying image, or when a close-up of a three-dimensional object is taken, an accurate shape cannot be grasped due to the shadow.

[0003] Conventionally, as a method of preventing this, a method of softening a shadow, for example, irradiating an umbrella-shaped reflecting member called an umbrella with a flash light to illuminate a subject with the reflected light in order to enlarge a light emitting portion. I was Also, a special so-called close-up strobe for preventing shadows from appearing only in close-up photography has been commercialized.

Another problem in flash photography is that
For example, one often experiences troubles such as the reflection of the glass of a shop window and the shining of glasses when photographing a person. To prevent that glass reflection,
It was necessary to predict the occurrence of reflected light in advance, shift the angle between the glass and the photographing optical axis, and move the flash light emitting unit away from the camera to a position where reflection does not occur.

[0005]

However, the method using the reflecting member is very large in size, and is not generally used because the location of the photographing, the skill of the photographer, and the like are large.

[0006] Although a technique using a special strobe for close-up photography is effective in that it does not cast shadows during close-up photography,
In other photographing, since the light emitting portion of the flash is close to the photographing optical axis, for example, in a person photographing, a phenomenon called so-called red-eye is likely to occur and reflection is likely to occur.

Regarding the reflection of glass or the like, which is another problem, the photographer often depends on the photographer's skill to some extent, and can be dealt with only by experienced photographers. Did not.

The present invention has been made under such circumstances, and has as its object to provide a photographing apparatus, a photographing system, a photographing method, and a storage medium that can easily avoid the adverse effects of flash emission. Things.

[0009]

In order to achieve the above-mentioned object, according to the present invention, a photographing apparatus is set as follows in (1) to (7), and a photographing system is set as follows in (8). To the next (9) and the storage medium to the next (1)
0).

(1) A first flash light emitting portion disposed at a predetermined distance from the optical axis of the photographing lens, and a second flash light emitting portion disposed at a position different from the first flash light emitting portion and the optical axis of the photographing lens. Flash light emitting portion, and the first flash light emitting portion and the second flash light emitting portion were alternately fired and photographed, and the data of the two photographed images was combined to generate one image. Control means for controlling the result image data to be stored in the memory means.

(2) In the photographing apparatus according to the above (1), when the control means combines the data of the two photographed images, the control means preferentially combines data having higher luminance among the image data. An imaging device that does

(3) In the photographing apparatus according to the above (1), the control means preferentially composes data of lower luminance among the image data when composing the data of the two photographed images. An imaging device that is a thing.

(4) In the photographing apparatus according to the above (1), the control means averages and combines the image data when combining the data of the two photographed images.

(5) A first flash light emitting portion arranged at a position separated from the optical axis of the photographing lens by a predetermined amount, and a first flash light emitting portion and a position substantially symmetrical with respect to the optical axis of the photographing lens. When taking a second flash light-emitting portion and shooting each of the first flash light-emitting portion and the second flash light-emitting portion alternately, when taking a first image using the first light-emitting portion Is to emit a flash immediately before the end of the integration of the image signal of the photoelectric conversion element, and then to emit a flash immediately after the start of the integration of the image signal of the photoelectric conversion element during the second image capturing using the second flash emission unit. A photographing apparatus comprising:

(6) The photographing apparatus according to the above (1) or (5), further comprising a mechanical shutter, wherein exposure start of photographing by light emission of the first flash unit is performed by an electronic shutter, and The photographing apparatus in which the exposure of the photographing by the light emission of the flash light emitting unit is completed by the mechanical shutter.

(7) The photographing apparatus according to (4), wherein gamma conversion of an image signal is performed before combining the data of the two photographed images.

(8) A photographing device in which a first flash light-emitting portion and a second flash light-emitting portion are separately arranged around a photographing lens, and the first flash light-emitting portion emits light from the photographing device for photographing. Receiving the signal of the first image and the signal of the second image photographed by emitting light from the second flash unit, and combining the signal of the first image and the signal of the second image to obtain a desired image. An imaging system comprising: a computer that forms a signal of the image.

(9) A photographing method using a photographing device in which a first flash light-emitting unit and a second flash light-emitting unit are spaced apart around a photographing lens, wherein the first flash light-emitting unit emits light. A first step of photographing, a second step of photographing the second flash unit by emitting light, and a signal of the image photographed in the first step and an image signal of the image photographed in the second step. A third step of synthesizing the signals to obtain a signal of a required image.

(10) A storage medium storing a program for realizing the photographing method according to the above (9).

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to embodiments of a digital camera. The present invention can be similarly implemented in the form of a photographing method and a storage medium storing a program for realizing the photographing method.

[0021]

(Embodiment 1) FIG. 1 is an external view schematically showing a "digital camera" according to Embodiment 1 (embodiments 2 to be described later).
The appearance of the third embodiment is also as shown in FIG. ). In FIG. 1, reference numeral 1 denotes a first flash light emitting unit, 2 denotes a second flash light emitting unit, 3 denotes a photographing lens, and 4 denotes a finder opening.

FIG. 2 is a circuit block diagram of the present embodiment.
In the figure, 5 is a CCD (photoelectric conversion element), 6 is CC
AGC / CDS circuit that samples and holds the output of D5 to adjust the signal level, 7 is an A / D conversion circuit that A / D converts the output of AGC / CDS circuit 6, and 8 is the output of A / D converted CCD5. To generate an image signal for each pixel by interpolation, and further generate an image signal separated into a luminance signal and a chrominance signal. Reference numeral 9 denotes a memory circuit that temporarily holds the processed image signal, 10 denotes a CPU that controls the flow of the signal, and 11 denotes a flash memory that finally stores the captured image. 12 is a booster circuit for generating a high-voltage power supply for flash light emission, 13 is a main capacitor which receives the output of the booster circuit 12 and stores the energy of flash light emission, and 14a and 14b are triggers for generating high-voltage pulses for triggering flash light emission. Circuits, 15a and 15b are xenon tubes that emit flash light, and 16a and 16b are control elements generally called IGBTs that control the current flowing through the xenon tubes 15a and 15b to control the amount of flash light emission. 17a,
Reference numeral 17b denotes a photoelectric sensor such as an SPC which is disposed near the xenon tubes 15a and 15b and receives a part of the flash light and feeds back the light emission amount of the flash. Reference numeral 18 denotes a flash light which comprehensively controls the operation of the flash light emitting unit. It is a control circuit.

Next, a specific operation will be described with reference to the drawings.

First, when the photographer wishes to take a picture without the shadow of the flash light for photographing such as close-up photography, the mode is set by a switch (not shown) or the like, and preparation for operation is started in accordance with the mode. . When a release button (not shown) is pressed toward the subject, a photographing operation is started, and after a photographing preparation operation such as auto focus (not shown) is performed, a first exposure is started. CCD5
Immediately before the end of the exposure operation (integration of the image signal), the first flash light emitting section 1 (15a) emits light. At this time, the flash light emission control circuit 18 is controlled based on the output of the first feedback sensor 17a so that the light emission amount becomes a preset light emission amount.
Is controlled by Immediately after that, the image signal is transferred to the vertical CCD and the transfer of electric charge is started, and at the same time, the second exposure is started. Immediately after the start of the exposure, the second flash sensor 2 (15b) starts to emit light so that the second feedback sensor 1 can emit the same amount of light as the first light emission.
It is controlled by the flash light emission control circuit 18 based on the output of 7b.

The image signal read in the first exposure is the signal AG
Image processing circuit 8 passing through C / CDS 6, A / D conversion circuit 7
Are separated into a luminance signal and a color difference signal, and stored in the memory 9. Thereafter, the image signal read by the second exposure is stored in another place of the memory 9 in the same manner.

Thereafter, the luminance signal and the color difference signal of each corresponding point are sequentially read out from the two image signals, and the luminance signals are compared to be synthesized into one image using the higher level or equivalent luminance signal and color difference signal. And store it in the memory 9 again. At this time, the first exposure signal or the second exposure signal may be rewritten to save the capacity of the memory 9. Thereafter, the combined image signal is read out, and compression processing and various data are added by the CPU 10 or the like and stored in the flash memory 11, and a series of operations is completed. These timings are shown in FIG.

FIG. 4 is a flowchart showing an outline of the operation of the above-described mode for taking a picture without the shadow of flash emission. In step S (step) 41, image data obtained by the light emission of the first flash light emitting unit 1 is acquired from the CCD 5, and in step S42, A / D conversion is performed and image processing (separation into a luminance signal and a color difference signal) is performed. To store. At S43 in parallel with S42, the second flash light emitting unit 2 is
The image data obtained by the light emission is acquired, A / D converted and image-processed in S44, and stored in the memory 9. S45, S46
Then, the luminance signal and the color difference signal of both images are read from the memory 9 and the luminance signals are compared. When the level of the second data is higher than the level of the first data and when the level is the same, the process goes to S47. Then, the second data is stored in the memory 9, and at other times, the first data is stored in the memory 9. S
At 49, it is determined whether or not all pixel data has been compared. If not, the process returns to S45, and S45 to S49.
Is repeated until the comparison of all pixel data is completed. In this flowchart, the processing in S42 is performed in parallel with the processing in S43 and S44 for the purpose of speeding up the processing. However, the processing in S43 and S44 may be performed after the processing in S42.

Next, the operation for taking a picture in which the reflected light of the flash is canceled will be specifically described.

The mode is set via a switch (not shown) in the same manner as in the case of the above-described photographing for eliminating the shadow. A shooting preparation operation is started and a first exposure is started in the same manner as the shooting for eliminating the shadow. Similarly, the first flash unit 1 is caused to emit light immediately before the completion of the exposure, and the second exposure is started simultaneously with the reading of the image signal. Each image signal is taken into the memory 9. The operations up to this point are exactly the same as those of the above-described shooting for eliminating shadows.

After that, the image signal of each corresponding point is read out from both the captured image signals, and the data of the luminance signal and the chrominance signal having the lower luminance signal level or equivalent are adopted. Combine. Similarly, the completed image signal is temporarily stored in the memory 9 and then subjected to compression processing and various data by the CPU 10 and then to the flash memory 1.
Written to 1.

FIG. 5 schematically shows the operation of the mode for taking a picture in which the reflected light of the flash light emission is canceled as described above.
Is shown in the flowchart of FIG. The processing of S51 to S55 is shown in FIG.
And the description is omitted.

In this mode, when the data level of the second sheet is lower than or equal to the data level of the first sheet in S56, the second data is stored in the memory 9 in S57. Otherwise, the first data is stored in the memory 9 in S58. The process in S59 is the same as S49.

That is, according to the present embodiment, a simple operation can be performed at the time of flash photographing of a so-called digital camera using a photoelectric conversion element for capturing an image, and photographing can be performed by using a device while avoiding the adverse effects of flash light emission. In the past, silver halide cameras required a large amount of equipment for shooting and it was very difficult to shoot without a professional photographer. Thus, a highly useful digital camera is realized.

In addition, it is possible to avoid that the glasses of glasses, which are common in portraits of people generally performed, shine or fly white due to the reflection of glossy objects such as glass. It is an extremely useful new value added only by a digital camera that can be monitored.

In some cases, there is no shadow of the subject at all, but there is a case where there is no shadow of the subject, but when there is a dark shadow, it is difficult to see the shadow. To cope with this, an arbitrary average is obtained by taking two images in the present embodiment, separating the two images into a luminance signal and a color difference signal, appropriately performing gamma conversion, and then taking an average of the two image signals. It is possible to generate an image having the strength of the shadow. After generating the image, the gamma conversion may be performed again to obtain an originally desired image signal. Alternatively, instead of gamma conversion, addition may be performed by multiplying by a coefficient at the time of addition. For example, it is also possible to add a half image signal of a darker method to a brighter image signal, add the divided signal, and divide by 1.5 to add a slight shadow. In this embodiment, it is assumed that processing is performed in the camera. However, depending on the application, it may be more convenient to perform processing on a personal computer afterwards so that more detailed settings can be made. For such applications, the camera is also set to have a mode in which a paired signal is added as it is without combining two images in the camera and saved as two images and processed by a personal computer. It is also effective.

The layout of the light emitting portion of the flash is preferably arranged symmetrically with respect to the optical axis of the photographing lens, but does not necessarily have to be point symmetric. If the positions of the light emitting units are not exactly the same, there are some effects. The distance from the optical axis does not need to be the same.

As described above, according to this embodiment,
By simply setting the mode in advance, it is possible to easily obtain a photograph without the shadow of the flash emission, a photograph in which the reflected light of the flash emission is canceled, and the like.

(Embodiment 2) The hardware configuration of this embodiment is such that a mechanical shutter (mechanical shutter) is added to the configuration of Embodiment 1 (FIG. 2). In the first embodiment, there is no problem when the light of the flash is sufficiently stronger than the ambient light. However, when the ambient light cannot be ignored, the time difference between the first image integration and the second image integration (1/30 second for a frame in the case of a normal video, and further time difference for a digital camera depending on the number of pixels). (There is a possibility that the image becomes large), and the image is blurred by exposure to ambient light. To prevent this, it is effective to use an electronic shutter and a mechanical shutter together, control the start of the first exposure with the electronic shutter, and perform the completion of the second exposure with the mechanical shutter. This embodiment realizes this. As in the first embodiment, when a release button (not shown) or the like is pressed, a mechanical shutter (not shown) starts to open according to a command from the CPU 10 after a predetermined shooting preparation operation. After the first image integration started immediately before and after the image integration is once reset, the integration of the image signal is performed again, and then the reading operation is started. This is a so-called electronic shutter mode in which the actual time after reset is set to, for example, about 1/500 second. Similarly, the first flash emission is performed immediately before the completion of the exposure, and the second image integration is started simultaneously with the completion of the first exposure. Immediately, the flash is emitted and the mechanical shutter is closed. 1/500 from the start of integration with the mechanical shutter
The closing operation is performed in about seconds. Thereafter, reading of the second image signal is performed at a predetermined timing.

As described above, the exposure time is determined by the electronic shutter for the integration of the first image signal, and the exposure time is determined by the mechanical shutter for the integration of the second image signal. As a result, the time lag of the exposure is very small. It is possible to capture image signals of two screens. In this case, the main exposure is by flash, so even if a slight error occurs between the first exposure time and the second exposure time, the result is hardly affected. FIG. 6 shows the timing.

(Embodiment 3) FIG. 7 is a block diagram showing a configuration of a "digital camera" which is Embodiment 3. In the figure, C
CD5, AGC / CDS6 and A / D7 are the same blocks as in the first embodiment. In the present embodiment, the A / D-converted image signal is directly loaded into the memory 9 first. Then, C
The PU 10 compares the data of the two screens for each pixel according to the same purpose as in the first embodiment, and collects the higher-level data into one image signal, or collects the lower-level data into one image signal. The data is sent to the image signal processing unit 8 for the first time after performing an operation such as making a single image signal, and the image signal is separated and synthesized into a luminance signal and a color difference signal. Thereafter, similar to the first embodiment, the CPU 10 performs processing such as compression again, and adds various data and writes the data to the flash memory 11.

In this embodiment, as compared with the first embodiment, the processing of the image signal processing section is only for one screen, so that the processing section can be used even if the processing speed is low.
Therefore, it can be configured with a very simple circuit and can be applied to a relatively inexpensive camera. However, when an image is monitored or the like, display can be performed only after complete processing, but in the first embodiment, it is also possible to display the progress of the first photographing result, the second photographing result, and the like.

[0042]

As described above, according to the present invention,
The adverse effects of flash emission can be easily avoided.

[Brief description of the drawings]

FIG. 1 is an external view of a first embodiment.

FIG. 2 is a circuit block diagram of a first embodiment;

FIG. 3 is a timing chart showing the operation of the first embodiment;

FIG. 4 is a flowchart showing an operation of taking a picture without shadow of flash emission.

FIG. 5 is a flowchart showing an operation of taking a picture in which reflected light of flash light is canceled.

FIG. 6 is a flowchart illustrating the operation of the second embodiment.

FIG. 7 is a block diagram illustrating a configuration of a third embodiment;

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 First flash unit 2 Second flash unit 3 Photographic lens

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 5/91 H04N 5/91 J

Claims (10)

[Claims] 1. A first flash light emitting unit disposed at a position separated by a predetermined amount from an optical axis of a photographing lens, and a second flash light emitting unit disposed at a position different from the first flash light emitting unit and the optical axis of the photographing lens. Flash light emitting portion, the first flash light emitting portion and the second flash light emitting portion alternately emit light, each photographed, the result of generating one image by combining the data of the two captured images Control means for controlling the image data to be stored in the memory means. 2. A photographing apparatus according to claim 1, wherein said control means preferentially combines data having a higher luminance among the image data when combining the data of the two photographed images. An imaging device, comprising: 3. The photographing apparatus according to claim 1, wherein said control means preferentially combines lower-luminance data of the image data when combining the data of the two photographed images. An imaging device characterized by the above-mentioned. 4. The photographing apparatus according to claim 1, wherein the control means averages and combines the image data when combining the data of the two photographed images. . 5. A first flash light emitting unit disposed at a position separated by a predetermined amount from an optical axis of a photographing lens, and a first flash light emitting unit disposed at a position substantially symmetrical with respect to the optical axis of the first flash light emitting unit and the photographing lens. At the time of shooting the first image using the first flash unit, the second flash unit and the first flash unit and the second flash unit are alternately flashed to shoot each. A flash is emitted immediately before the end of the integration of the image signal of the photoelectric conversion element, and a flash is emitted immediately after the start of integration of the image signal of the photoelectric conversion element during the second image shooting using the second flash emission unit. A photographing apparatus comprising: a control unit for controlling. 6. The photographing apparatus according to claim 1, further comprising a mechanical shutter, wherein an exposure start of photographing by light emission of said first flash light emitting unit is performed by an electronic shutter, and said second flash light emitting unit is provided. A photographing apparatus that terminates exposure for photographing by emitting light from the mechanical shutter. 7. The photographing apparatus according to claim 4, wherein gamma conversion of an image signal is performed before combining data of the two photographed images. 8. A photographing device in which a first flash light-emitting unit and a second flash light-emitting unit are arranged separately around a photographing lens, and the first flash light-emitting unit emits light from this photographing device for photographing. The signal of the first image and the second
A computer that receives a signal of a second image captured by emitting light from the flash light emitting unit and combines the signal of the first image and the signal of the second image to form a signal of a required image An imaging system characterized by the following. 9. A photographing method using a photographing device in which a first flash light-emitting unit and a second flash light-emitting unit are spaced apart around a photographing lens, wherein the first flash light-emitting unit emits light. A first step of photographing, a second step of photographing the second flash unit by emitting light, a signal of the image photographed in the first step, and a signal of the image photographed in the second step And obtaining a signal of a required image by combining the two. 10. A storage medium storing a program for realizing the photographing method according to claim 9.