JP2001157216A - Image pickup device and image pickup method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To pick up an object image where no false color is produced without the need for an optical LPF. SOLUTION: When a shutter key is operated, two shots are consecutively executed (step S2). The picked-up 1st image is compared with the 2nd image (step S3) to discriminate whether or not a false color signal is produced (step S4). In the discrimination as to whether or not a false color signal is produced, whether or not there is any color change between the 1st and 2nd images is discriminated, and when any color change exists, it is discriminated that the false color signal is produced, and when no color change exists, it is discriminated that no false color signal is produced. In the case that it is discriminated that no false color signal is produced, whether or not the 1st image data have already been recorded is discriminated (step S5) and when the 1st image data have not been recorded, the 2nd image data are recorded in a recording memory and stored (step S6).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an imaging apparatus and an imaging method using a solid-state imaging device.

[0002]

2. Description of the Related Art Conventionally, a CCD is used by an imaging lens.
2. Description of the Related Art There is known an imaging apparatus that forms a subject image on a (charge-coupled device) and records the image data in a memory. In this imaging apparatus, as shown in FIG. 4, an optical LPF (low pass filter) 33 is disposed between an imaging lens 31 and a single-plate CCD 32, and
By cutting high frequency range by PF33,
We are trying to remove false colors.

That is, as shown in FIG. 5, a CCD color separation filter 34 of the single-plate CCD 32 and a stripe 37 in which black stripes 35 and white stripes 36 are repeated at the same pitch.
In the illustrated state, there is an output at "R" of the CCD color separation filter 34, but no output at "G" and "B". Therefore, in spite of the fact that the stripes 37 are formed by repeating the black stripes 35 and the white stripes 36,
The data becomes red, and this red signal is a false color signal. Therefore, in the conventional imaging apparatus, the optical LPF 33 is disposed between the imaging lens 31 and the CCD 32 to reduce the response in a high frequency range, thereby removing a false color signal.

[0004]

However, the optical L
When the PF is used, the response of a low-frequency component that is not related to a false color is also reduced due to its characteristics, which is one of the causes of lowering the quality of a captured image. In addition, when there is no high-frequency component causing a false color in the subject image, the arrangement of the optical LPF has no merit and merely adversely affects the image.

The present invention has been made in view of such a conventional problem, and provides an image pickup apparatus and an image pickup method capable of picking up a subject image without generation of a false color without using an optical LPF. It is intended to do so.

[0006]

According to a first aspect of the present invention, there is provided an imaging apparatus for imaging an object image a plurality of times, and a plurality of images captured by the imaging means. And a recording unit that records the subject image for which it has been determined that no false color signal has been generated by the determination unit. That is, when the shutter operation is performed, the subject image is captured a plurality of times, for example, two subject images are continuously captured. At this time, since the imaging is usually performed by holding the imaging device by hand, it is extremely unlikely that the first and second images are exactly the same, and a slight difference occurs between the two. Therefore, when a monochrome stripe is picked up as the subject image, the relative position between the monochrome stripe and the color separation filter changes between the first and second times, and the generation state of the false color signal also changes. Therefore, the two captured subject images are compared, and if there is no color change between them, it can be determined that no false color signal has been generated at the time of capturing the subject image. Then, in this case, the captured subject image is recorded, so that only the subject image having no false color signal is recorded.

In the image pickup apparatus according to the second aspect of the present invention, the recording means records only one subject image for which it has been determined by the determining means that no false color signal has been generated. That is, as described above, when the shutter operation is performed, the subject image is captured a plurality of times, for example, two subject images in succession, but one of the subject images determined to have no false color signal is generated. Only are recorded. Therefore, duplicate recording of identical subject images is avoided.

In the image pickup apparatus according to the third aspect of the present invention, an image pickup means for picking up a subject image a plurality of times and a plurality of subject images picked up by the image pickup means are compared to generate a false color signal. Determining means for determining whether or not a false color signal has occurred, and, if the determining means determines that a false color signal has occurred, comparing the location where the false color signal has occurred with its surroundings to determine the correct color Means and recording means for recording a subject image for which it has been determined that the place where the false color signal has been generated has the correct color.

That is, as described above, the two captured subject images are compared, and if there is no color change between the two, it is determined that no false color signal has been generated in capturing the subject image. be able to. Therefore, if the color changes between the two, it can be determined that a false color signal has been generated at the time of capturing the subject image. When a false color signal is generated, the correct color is determined by comparing the portion of the subject image where the false color has occurred with the surrounding area. For example, the color around the place where the false color occurs is determined as the correct color at the place where the false color occurs. Then, of the two subject images, a subject image in which only the portion where the false color has occurred is determined to be the correct color is recorded, whereby a subject image without false color is recorded. Becomes

Further, in the image pickup apparatus according to the present invention, an image pickup means for picking up an object image a plurality of times and a plurality of object images picked up by the image pickup means are compared, and a false color signal is obtained. Determining means for determining whether or not a false color signal has occurred, and, if the determining means determines that a false color signal has occurred, comparing the location where the false color signal has occurred with its surroundings to determine the correct color Means, correction means for correcting the location where the false color signal is generated to the correct color in accordance with the determination by the determination means, and recording means for recording the subject image corrected by the correction means.

That is, when a false color is included in each captured image of a subject, the correct color of the portion including the false color is determined, and the portion where the false color occurs is corrected to the correct color. And then record the subject image. Therefore, in the case of this imaging device, unlike the imaging device of claim 3,
Even if all of the captured subject images include a false color, the subject image is recorded without the false color by being corrected.

Further, in the image pickup apparatus according to the present invention, there is further provided a selecting means for selecting, from among the plurality of subject images, a subject image having many portions determined to be correct by the determining means. The correction means corrects the subject image selected by the selection means. In other words, the subject image selected by the selection unit has many portions determined to be correct colors and has few portions to be corrected, so that correction can be easily performed.

In the image pickup apparatus according to the present invention, an image pickup means for picking up a subject image a plurality of times and a plurality of subject images picked up by the image pickup means are compared to generate a false color signal. Determining means for determining whether or not a false color signal has occurred; and correcting means for correcting the place where the false color signal has occurred to a predetermined color such as black and white when the determining means determines that a false color signal has occurred. Recording means for recording the subject image corrected by the means.

In other words, in the case of this imaging apparatus, the correct color is not determined and the correction is performed as in the invention of claim 4, but the place where the false color occurs is simply changed to a predetermined color of white or black. Correct and record. Therefore, the correction process is facilitated, and a subject image without false colors is recorded by the easy correction process.

Further, in the image pickup apparatus according to the present invention, the correcting means corrects only one subject image, and the recording means controls only the subject image corrected by the correcting means. Record Therefore, no time is required for the correction process, and duplicate recording of the same subject image is avoided.

In the imaging method according to any one of the eighth to eleventh aspects, the same effect can be obtained by including the steps corresponding to the various means in the imaging device according to the above aspect.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a main part of a digital camera according to an embodiment of the present invention. As shown in FIG. 1, the digital camera includes an imaging lens 1 composed of a plurality of lenses, and a CCD 2 is arranged behind the imaging lens 1.

FIG. 2 is a block diagram showing a schematic configuration of the digital camera. An output signal from the CCD 2 is processed by a signal processing circuit 7 and is taken into a display RAM 10 and a work RAM 14 by a CPU 8. C
PU8 operates based on a program,
The digital camera controls various components of the digital camera. The CCD 2 and the display RAM 10 are connected, and a key input unit 11, an external I / F control unit 12,
The ROM 13, the working RAM 14, and the recording memory 15 are connected.

The key input unit 11 includes a power key operated when the power is turned on and off, a shutter key operated when two image data are stored in the work RAM 14 as described later, and a recording standby mode. There are provided various keys such as a mode key for selectively setting the playback mode and the playback mode. The external I / F control unit 12 controls data input / output with an external device such as a personal computer connected to the digital camera. The ROM 13 stores an operation program of the CPU 8 and the like, and the CPU 8 operates based on the operation program and controls each unit. Working RAM
Reference numeral 14 is used not only as a work area for the CPU 8 but also for recording two image data taken in with the operation of the shutter key.

The display RAM 10 stores the CCD 2 processed by the signal processing circuit 7 in the recording standby mode.
The image data of the subject image based on the output signal from is stored at each predetermined timing. When the display circuit 16 drives the display element 17 based on the image data, the subject image formed on the CCD 2 by the imaging lens 1 is displayed on the display element 17 composed of an LCD. In the reproduction mode, the image data read from the recording memory 15 is stored, and the display circuit 16 drives the display element 17 based on the image data, so that the recorded image data is An image based on the image is displayed on the display element 17.

In the present embodiment according to the above configuration, when the recording standby mode is set, the CPU 8
The control is executed according to the flowchart shown in FIG. 3 based on the program stored in M13. That is,
The standby state is maintained until the shutter key provided on the key input unit 11 is operated (step S1). If the shutter key is operated, two shots (2
Is performed (step S2). By the processing in step S2, the CCD 2 continuously outputs the image signal of the subject image twice within a predetermined minute time according to the instruction from the CPU 8, and this image signal is processed by the signal processing circuit 7, It is stored in the working RAM 14. Therefore, the work RAM 14 stores the image data of the time when the user of the digital camera operates the shutter key (first image) and the subject image (second image) a minute after this.

Next, the first and second images stored in the working RAM 14 are compared (step S3), and it is determined whether or not a false color signal has been generated (step S4).
In determining whether or not the false color signal has been generated, it is determined whether or not there is a color change between the first and second images, and if there is a color change, a false color signal is generated. It is determined that no false color signal has been generated if there is no color change.

That is, since the image is usually picked up by holding the digital camera by hand, it is extremely unlikely that the first and second images will be exactly the same, and there will be a slight difference between the two. Therefore, when a monochrome stripe is picked up as the subject image, the relative position between the monochrome stripe and the color separation filter changes between the first and second times, and the generation state of the false color signal also changes. Therefore, the two captured subject images are compared, and if there is no color change between them, it can be determined that no false color signal has been generated at the time of capturing the subject image.

Then, in this case, it is determined whether or not the first image data has already been recorded in the recording memory 15 (step S5). Is recorded and stored in the recording memory 15 (step S6). Therefore, when no false color has occurred in any of the first and second captured images, only one of the image data is recorded in the recording memory 15. Therefore, duplicate recording of identical subject images can be avoided, and the recording memory 15 can be used efficiently.

On the other hand, if it is determined in step S4 that a false color signal has been generated, the "correct color" is determined by comparing the place where the false color signal is generated with the surrounding colors (step S7).
That is, the location where the false color has occurred is compared with the surrounding colors, and the same color as the surrounding color is determined as the “correct color” of the location where the false color has occurred. Next, of the two subject images,
An image having more "correct colors" where a false color signal is generated is selected (step S8).

Further, it is determined whether or not the portion where the false color signal of the image selected in step S8 has occurred is only the "correct color" (step S9). If there is only the "correct color", the image data of the subject image selected in step S8 is recorded and stored in the recording memory 15 (step S10). No subject image will be recorded.

If the image selected in step S8 contains not only the "correct color" but also a false color signal as a result of the determination in step S9, the place where the false color signal is generated is determined. Correct to “correct color” (step S
11). Here, as described in step S7, the “correct color” is the same color as the color around the location where the false color has occurred, and the location where the false color has occurred is corrected to the same color as the surrounding color. Is done. Then, the corrected image data of the subject image is recorded and stored in the recording memory 15 (step S12).

In the present embodiment, step S11
In the above, the place where the false color is generated is corrected to “correct color”, but it may be simply corrected to white or black. In this case, since the correction process is simple,
A subject image without false colors can be recorded by a simple correction process. Even in this case, step S8 is performed in advance.
Since either one of the subject images is selected, only one subject image is stored after correction, and the recording memory 15 can be used efficiently. Also, it was assumed that two images were taken continuously, but the number is not limited to two, but three,
Four or more images may be compared.

Further, two shots are taken continuously after the shutter key is pressed, but the image before the shutter key is pressed may be automatically taken as the first image to be compared. good.

[0030]

As described above, according to the present invention, a plurality of captured subject images are compared, and a subject image determined to have no false color signal or a portion where the false color is generated has a correct color. Since a subject image determined to be present and a subject image in which a portion where a false color occurs is corrected to a correct color or a predetermined color are recorded, a subject image without a false color is recorded without using an optical LPF. be able to. Therefore, a subject image free from false color is recorded without demerits caused by using the optical LPF, such as a decrease in response of a low-frequency component irrelevant to false color and a decrease in image quality. be able to.

Further, since the correction is performed by selecting a subject image having many portions determined to be correct colors and having few portions to be corrected, correction can be easily performed.
In addition, even if a plurality of images are taken in response to one shutter operation, only the selected and corrected subject image or only one subject image determined to have no false color signal is recorded. Accordingly, it is possible to efficiently record images while avoiding duplicate recording of subject images having the same identity.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an arrangement configuration of an imaging lens to a CCD of a digital camera according to an embodiment of the present invention.

FIG. 2 is a schematic block diagram of the digital camera.

FIG. 3 is a flowchart illustrating a processing procedure of a CPU according to the embodiment;

FIG. 4 shows a conventional digital camera from an imaging lens to a CCD.
FIG. 2 is a cross-sectional view showing an arrangement configuration up to this point.

FIG. 5 is an explanatory diagram showing a principle of generating a false color signal.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 imaging lens 2 CCD 7 signal processing circuit 8 CPU 11 key input unit 14 working RAM 15 recording memory

Claims (11)

[Claims] An imaging unit that captures a subject image a plurality of times; a determination unit that compares a plurality of subject images captured by the imaging unit to determine whether or not a false color signal is generated; Recording means for recording a subject image determined to have no false color signal. 2. The imaging apparatus according to claim 1, wherein the recording unit records only one subject image for which the determination unit has determined that no false color signal has been generated. 3. An image pickup means for picking up a subject image a plurality of times, a plurality of subject images picked up by the image pickup means, and a judging means for judging whether or not a false color signal has been generated; When it is determined that a false color signal is generated, a determination unit that determines a correct color by comparing a location where the false color signal is generated and its surroundings, and the false color signal is generated by the determination unit. Recording means for recording a subject image determined to have a correct color at a location. 4. An image pickup means for picking up an object image a plurality of times, a plurality of object images picked up by the image pickup means, and a judgment means for judging whether or not a false color signal is generated, When it is determined that the false color signal is generated, a determination unit that determines a correct color by comparing a location where the false color signal is generated and its surroundings, and according to the determination by the determination unit, the false color signal is An image pickup apparatus comprising: a correction unit that corrects a generated portion to the correct color; and a recording unit that records a subject image corrected by the correction unit. 5. The image processing apparatus according to claim 1, further comprising: a selection unit that selects a subject image having many portions determined to be correct colors by the determination unit from among the plurality of subject images, wherein the correction unit selects the subject selected by the selection unit. The imaging device according to claim 4, wherein the image is corrected. 6. An image pickup means for picking up an object image a plurality of times, a judgment means for comparing a plurality of object images picked up by the image pickup means and judging whether or not a false color signal is generated, and When it is determined that a false color signal is generated, a correction unit that corrects a portion where the false color signal is generated to a predetermined color such as black and white, and a recording unit that records a subject image corrected by the correction unit are provided. An imaging device, comprising: 7. The imaging apparatus according to claim 6, wherein the correction unit corrects only one subject image, and the recording unit records the subject image corrected by the correction unit. 8. An imaging step of imaging a subject image a plurality of times, a determining step of comparing the plurality of subject images captured in the imaging step to determine whether or not a false color signal is generated; A recording step of recording a subject image determined to have no false color signal. 9. An image capturing step of capturing a subject image a plurality of times, a determining step of comparing the plurality of subject images captured in the capturing step to determine whether or not a false color signal has been generated; If it is determined that a false color signal has been generated, a portion where the false color signal is generated is compared with its surroundings,
An imaging method, comprising: a determining step of determining a correct color; and a recording step of recording a subject image in which the location where the false color signal is generated is determined to be a correct color in the determining step. 10. An imaging step of imaging a subject image a plurality of times, a comparing step of comparing the plurality of subject images captured in the imaging step to determine whether or not a false color signal is generated; If it is determined that a false color signal has been generated, a portion where the false color signal is generated is compared with its surroundings,
A determining step of determining a correct color; a correcting step of correcting a portion where the false color signal is generated to the correct color in accordance with the determination in the determining step; and a recording step of recording a subject image corrected in the correcting step. An imaging method, comprising: 11. An image capturing step of capturing a subject image a plurality of times, a determining step of comparing the plurality of subject images captured in the capturing step to determine whether or not a false color signal is generated; When it is determined that a false color signal is generated, a correction process of correcting a portion where the false color signal is generated to a predetermined color such as black and white, and a recording process of recording the subject image corrected in the correction process are performed. An imaging method characterized by including: