JP2008092299A - Electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for a user to promptly confirm a failure image in photography of the failure image. <P>SOLUTION: This electronic camera is provided with an imaging part (12), an image determination part (16) and a display part (19). The imaging part photographs a subject image to generate data about a photographed image. The image determination part determines whether the photographed image has a failure. When determined that the photographed image has a failure, the display part enlarges a partial area of the failure image including a failure part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electronic camera having a function of notifying a user of taking a failed image.

Conventionally, as shown in Patent Document 1, an electronic camera that notifies a user with voice or the like at the time of shooting a failed image and prompts re-shooting is known.
JP 2004-120256 A

However, in the above-mentioned Patent Document 1, the user cannot quickly confirm what kind of failed image was taken. For this reason, there is still room for improvement in that the user cannot quickly determine how to perform appropriate shooting at the time of re-shooting and may repeatedly shoot the same failed image as the previous time.
The present invention is to solve the above-mentioned problems of the prior art. An object of the present invention is to provide a means by which a user can quickly confirm what kind of failure image was taken when the failure image was taken.

An electronic camera according to a first aspect includes an imaging unit, an image determination unit, and a display unit. The imaging unit captures a subject image and generates captured image data. The image determination unit determines whether the captured image is a failed image. When the image determination unit determines that the image is a failure image, the display unit enlarges and displays the partial region of the failure image including the failure part.
In a second aspect based on the first aspect, the image determination unit performs image analysis on the captured image data, and determines a captured image as a failed image when a failure location is detected in the image analysis.

In a third aspect based on the second aspect, the image determination unit divides the captured image into a plurality of small regions and executes image analysis. Further, the display unit displays an enlarged image of the small area where the failure point is detected.
According to a fourth invention, in any one of the first to third inventions, the failure image includes a shooting failure caused by any of camera shake, subject blur, red-eye state, and blinking state.

According to a fifth invention, in any one of the first to fourth inventions, when the image determination unit determines that the image is a failure image, the identification data indicating the failure image is associated with the captured image data. The electronic data camera further includes an identification data generation unit.
In a sixth aspect based on the fifth aspect, the identification data generation unit further includes failure type data indicating the type of shooting failure in the identification data.

  In the present invention, the failure location that is the basis for the determination when the failure image is captured is enlarged and displayed on the display unit, and the user can quickly confirm what failure image was captured.

FIG. 1 is a block diagram showing the configuration of the electronic camera of this embodiment. In the present embodiment, an example of detecting a camera shake failure image will be described as an example of a failure image. Further, the present invention can be applied to an electronic camera having a solid-state imaging device such as a CCD or a CMOS, and can also be applied to still image shooting of a movie camera.
The electronic camera includes a photographic lens 11, an image sensor 12, an analog processing unit 13, a buffer memory 14, an image processing unit 15, an image determination unit 16, a recording I / F 17, a release button 18, and a monitor 19. And a CPU 20 and a bus 21. Note that the buffer memory 14, the image processing unit 15, the image determination unit 16, the recording I / F 17, the monitor 19, and the CPU 20 are connected via a bus 21.

The photographing lens 11 is composed of a plurality of lens groups such as a zoom lens for changing a photographing magnification and a focusing lens for adjusting a focus position. The photographing lens 11 is configured such that the position in the optical axis direction can be adjusted by a lens driving unit (not shown). In FIG. 1, the photographing lens 11 is illustrated as a single lens for convenience.
The image sensor 12 photoelectrically converts the light beam that has passed through the photographing lens 11 to generate an analog image signal of the subject image. Here, in the shooting mode of the electronic camera, the image sensor 12 captures a recording image (main image) at the time of release, and outputs a through image by thinning out at predetermined intervals even during standby for shooting. The through image data is used for image display on the monitor 19 and various arithmetic processes by the CPU 20.

  The analog processing unit 13 is an analog front end circuit having a CDS circuit, a gain circuit, an A / D conversion circuit, and the like. The CDS circuit reduces the noise component of the output of the image sensor by correlated double sampling. The gain circuit amplifies the gain of the input signal and outputs it. In this gain circuit, the imaging sensitivity corresponding to the ISO sensitivity can be adjusted. The A / D conversion circuit performs A / D conversion of the output signal of the image sensor. The output of this A / D conversion circuit is connected to the buffer memory 14. In FIG. 1, illustration of individual circuits in the analog processing unit 13 is omitted.

The buffer memory 14 temporarily records captured image data before and after image processing by the image processing unit 15 and image analysis by the image determination unit 16.
The image processing unit 15 performs various kinds of image processing on the digital image signal at the time of release in the above-described shooting mode to generate data of the main image. Further, the image processing unit 15 generates a display image on the monitor 19 from data of the through image and the main image according to an instruction from the CPU 20. The image processing unit 15 can also execute compression / decompression processing of the data of the main image.

The image determination unit 16 performs an image analysis on the data of the main image, and executes a failure image determination process for determining whether or not the captured image is a failure image.
A connector for connecting the recording medium 22 is formed in the recording I / F 17. The recording I / F 17 executes data writing / reading with respect to the recording medium 22 connected to the connector. The recording medium 22 is composed of a hard disk, a memory card incorporating a semiconductor memory, or the like. In FIG. 1, a memory card is illustrated as an example of the recording medium 22.

The release button 18 receives from the user an instruction input to start AF operation before shooting by a half-press operation and an instruction to start exposure at the time of shooting by a full-press operation. The output of the release button 18 is connected to the CPU 20.
The monitor 19 displays various images according to instructions from the CPU 20. The monitor 19 in this embodiment is a liquid crystal monitor. On the monitor 19, a through image is displayed as a moving image during shooting standby in the shooting mode. If the image determination unit 16 determines that the shooting has failed, the monitor 19 displays a magnified display of a partial area of the captured image that includes the failure location that is the basis for the determination. The monitor 19 can also display a menu screen on which various setting items can be input in a GUI (Graphical User Interface) format, a reproduction display screen of the main image, and the like.

  The CPU 20 is a processor that performs overall control of each unit of the electronic camera. The CPU 20 executes a known AF calculation, AE calculation, auto white balance (AWB) calculation and the like in the contrast detection method based on the through image data. Further, when the image determination unit 16 determines that the image is a failed image, the CPU 20 records identification data indicating that the captured image is a failed image in association with the captured image data.

Hereinafter, an example of the operation at the time of photographing by the electronic camera of the present embodiment will be described with reference to the flowchart of FIG.
Step 101: The CPU 20 drives the imaging device 12 to start acquiring a through image. The image sensor 12 outputs an image signal of a through image at predetermined intervals, and the through image is sequentially displayed on the monitor 19. Therefore, the user can determine the shooting composition based on the through image on the monitor 19.

Step 102: The CPU 20 determines whether or not the release button 18 is half-pressed by the user. If the release button 18 is half-pressed (YES side), the CPU 20 proceeds to S103. On the other hand, when the release button 18 is not half-pressed (NO side), the CPU 20 waits for a half-press operation of the release button 18 by the user.
Step 103: The CPU 20 executes AF of the photographing lens 11 based on the through image. Further, the CPU 20 executes AE calculation and AWB calculation based on the data of the through image, and determines the shooting conditions (exposure time, aperture value, imaging sensitivity, etc.) of the main image.

Step 104: The CPU 20 determines whether or not the release button 18 has been fully pressed by the user. When the release button 18 is fully pressed (YES side), the CPU 20 proceeds to S105. On the other hand, when the release button 18 is not fully pressed (NO side), the CPU 20 waits for the user to fully press the release button 18.
Step 105: The CPU 20 drives the image sensor 12 based on the shooting conditions in S103 to take a main image. The image signal of the main image output from the image sensor 12 is temporarily recorded in the buffer memory 14 via the analog processing unit 13.

  Step 106: In response to an instruction from the CPU 20, the image processing unit 15 reads the main image data buffered in S105 and performs image processing such as defective pixel correction, gradation correction, interpolation, and color conversion. Thereafter, the image processing unit 15 compresses the data of the main image after the above-described image processing in the JPEG format or the like. The main image data after the compression processing is finally recorded on the recording medium 22 by the CPU 20.

Step 107: Further, the image processing unit 15 performs resolution conversion of the main image according to an instruction from the CPU 20, and generates a freeze image in which the entire main image is reduced. Then, the CPU 20 displays the freeze image on the monitor 19 for a predetermined time after shooting. Note that the operations of S106 and S107 are performed almost simultaneously.
Step 108: The CPU 20 instructs the image determination unit 16 to execute a failed image determination process. The image determination unit 16 reads the main image data buffered in S105 (or the main image data recorded on the recording medium 22) and determines whether the main image is a failed image. Then, the image determination unit 16 outputs the analysis result data of the main image to the CPU 20.

  Here, the data indicating the analysis result includes data indicating whether or not the main image has failed to be captured. In addition, the analysis result data in the case where the main image has failed to capture includes failure type data indicating the type of shooting failure (for example, camera shake) and the failure location indicating the location of the failure location that is the basis for the determination. Data (for example, data specifying a partial region of the main image including a failed part) is further included. The specific content of the failed image determination process in S108 will be described later with reference to FIG.

  Step 109: The CPU 20 determines whether or not the main image captured this time is a failed image based on the result of the failed image determination process in S108. If the main image is a failed image (YES side), the CPU 20 proceeds to S110. On the other hand, when the main image is not a failed image (NO side), after the main image data is recorded on the recording medium 22, the CPU 20 ends a series of processes and enters a standby state for the next shooting.

  Step 110: The CPU 20 enlarges and displays the failed part of the main image on the monitor 19. Specifically, the CPU 20 outputs failure location data in the analysis result data (S 108) to the image processing unit 15. The image processing unit 15 trims the partial area of the main image including the failed part based on the failure part data, and enlarges the image of the partial area according to the resolution of the monitor 19. Then, the CPU 20 displays the enlarged image of the partial area on the monitor 19 for a predetermined time.

Step 111: Based on the analysis result data (S108), the CPU 20 generates identification data indicating that the main image is a failed image. Then, the CPU 20 records the identification data on the recording medium 22 in association with the data of the main image. Thereafter, the CPU 20 ends a series of processes and enters a standby state for the next shooting.
Here, the identification data can include the above-mentioned failure type data and failure location data. When recording the main image data in a file format that conforms to the Exif (Exchangeable image file format for digital still cameras) standard, the type data is recorded in the header of the main image data file using the MakerNote tag. May be. Of course, the type data may be recorded in a separate file independent of the data file of the main image.

Next, the failure image determination process (S108) will be specifically described with reference to the flowchart of FIG. Note that FIG. 3 illustrates an example of camera shake detection.
Step 201: The image determination unit 16 performs a two-dimensional differential operation (for example, differential filter processing or the like) on the data of the main image to generate an edge extraction image obtained by extracting the contour component of the main image.

  Step 202: The image determination unit 16 divides the edge extraction image (S201) into rectangular regions of a predetermined size. As an example, in this embodiment, the edge extraction image is divided into four equal parts vertically and horizontally and divided into 16 rectangular areas. Then, the image determination unit 16 determines the rectangular area having the largest edge element among the rectangular areas (that is, the rectangular area having the largest number of non-zero pixels whose pixel values are other than zero) as the attention area. To do.

Step 203: The image determination unit 16 extracts a range corresponding to the position of the attention area (S202) of the edge extracted image in the main image as the attention area of the main image. In FIG. 4, the main image in a camera shake state is schematically shown. FIG. 5 shows the result of extracting a region of interest from the main image of FIG.
Step 204: The image determination unit 16 performs a Fourier analysis on the attention area (S203) of the main image. Then, the image determination unit 16 calculates the sum of the power spectra of the high frequency components exceeding the predetermined frequency F in the attention area of the main image.

Step 205: The image determination unit 16 determines whether or not the sum of the power spectrum in S204 is larger than the threshold value T. If the sum of the power spectrum is larger than the threshold T (YES side), the image determination unit 16 proceeds to S206. On the other hand, when the sum total of the power spectrum is equal to or less than the threshold T (NO side), the image determination unit 16 proceeds to S207.
Step 206: In this case, the image determination unit 16 determines that the main image is not shaken. Then, the image determination unit 16 outputs to the CPU 20 analysis result data indicating that the main image is not a photographing failure. Thereafter, the CPU 20 returns to S109 in FIG.

  Step 207: In this case, the image determination unit 16 determines that the main image is shaken. Then, the image determination unit 16 outputs to the CPU 20 analysis result data including data indicating that the main image has failed to be photographed, failure type data indicating camera shake, and failure location data indicating the region of interest. To do. Thereafter, the CPU 20 returns to S109 in FIG. Here, in S110 of FIG. 2, if the CPU 20 displays on the monitor 19 an image obtained by enlarging the attention area of the main image, the CPU 20 can easily indicate the failed part of the main image to the user. In addition, in FIG. 6, the example of a display of the enlarged image corresponding to the main image of FIG. 4 is shown.

Hereinafter, the operational effects of the electronic camera in the present embodiment will be described.
In the electronic camera according to the present embodiment, when the image determination unit 16 determines that the image is a failure image, an enlarged image of the failure portion due to camera shake is displayed on the monitor 19 (S108 to S110). Therefore, the user can clearly recognize the state of the failed image captured this time from the enlarged image of the failed part displayed on the monitor 19. Then, it becomes easy for the user to determine how to correct the shooting conditions by re-shooting, and more efficient shooting is possible.

In the present embodiment, when the image determination unit 16 determines that the image is a failed image, identification data indicating that the main image is a failed image is recorded on the recording medium 22 in association with the data of the main image ( S111). Therefore, the user can easily extract data relating to the failed image from the captured image data group in the recording medium 22 by using the identification data.
For example, (1) when the main images on the recording medium 22 are sequentially played back in a slide show, the data of the failed images are excluded from the playback target, and (2) the data of the failed images are batched. Can be easily deleted, and (3) when the failed image is processed and corrected after completion of shooting, the data of the failed image to be corrected can be easily selected. Further, if the failure type data included in the identification data is used, the condition setting for extracting the failure image can be subdivided. In this case, failure images with different causes can be extracted separately, which further improves user convenience.

(Supplementary items of the embodiment)
(1) In the above embodiment, an example in which camera shake is detected in the failure image determination process has been described. However, the present invention is not limited to this, and it is also possible to detect red-eye, blinking eyes, subject blur, and the like by failure image determination processing.
For example, when red eyes are detected in the failure image determination process, it can be performed as follows. Here, the red eye refers to a phenomenon in which when a person is flash photographed using a camera or the like, the photographed person's eyes appear red like a rabbit eye. The eyes are red because the capillaries in the retina of the eye are reflected, and precisely the pupil part of the eyes is red. Depending on the shooting conditions, the eye may appear golden, and such a gold eye is also referred to as a red eye in this specification.

  First, the image determination unit 16 performs a known face detection process on the main image data. As an example, the image determination unit 16 detects a face area from the main image based on feature points such as eyebrow, eye, nose, and lip end points, face contour points, head vertices, and chin lower end points. Alternatively, the image determination unit 16 may extract the outline of the skin color area based on the color information of the subject, and may detect the face area by performing matching with a template of a face component prepared in advance. Second, the image determination unit 16 searches for a pupil region from the face region when a face can be detected from the main image. Third, the image determination unit 16 determines whether or not the color component of the pixel in the pupil region satisfies the conditional expression for red eyes. If the conditional expression is satisfied, the image determination unit 16 determines that the main image is a failed image in the red eye state. .

  Further, when detecting blinking in the failed image determination process, it can be performed in the following manner. First, the image determination unit 16 performs a known face detection process on the main image data. Second, secondly, the image determination unit 16 searches for the eye part from the face area when the face can be detected from the main image, and blinks the main image when the eye part cannot be detected. It is determined as a failed image.

  Furthermore, when detecting a subject blur in the failed image determination process, it can be performed as follows. In this case, the image determination unit 16 performs wavelet analysis on the main image data, and divides the main image data into four subbands LL, HL, LH, and HH. Here, since the HL sub-band includes a high-frequency component only in the vertical direction, the contour of the subject blurred in the horizontal direction does not appear. On the other hand, since the LH subband includes a high-frequency component only in the horizontal direction, the contour of the subject blurred in the vertical direction does not appear. The HH subband includes high-frequency components in both the vertical direction and the horizontal direction. Therefore, the image determination unit 16 can identify only the subject that has shaken in the horizontal direction in the image by comparing the subbands of HL and HH. Further, the image determination unit 16 can identify only the subject that is blurred in the vertical direction in the image by comparing the subbands of LH and HH.

  Of course, each algorithm in the above-described failure image determination processing is merely an example, and other known algorithms may be substituted. For example, the above-described camera shake detection may be performed by frequency analysis using wavelet analysis. At this time, it is also possible to distinguish between subject blur and camera shake using the output of a mechanical blur detection sensor (not shown). The image determination unit 16 can also detect subject blur by comparing two images with different shooting timings.

(2) In the above-described embodiment, the CPU 20 may display an enlarged image of the failed part after shooting instead of the freeze image.
(3) At the time of shooting a failed image in the above embodiment, the CPU 20 may cause the user to select whether or not to record the failed image data on the recording medium 22. In this case, the recording capacity of the recording medium 22 can be utilized more effectively during shooting.

(4) At the time of shooting the failed image in the above embodiment, the CPU 20 only associates the identification data with the main image data and records it on the recording medium 22, and displays an enlarged display of the failed part on the monitor 19. It may be omitted.
It should be noted that the present invention can be implemented in various other forms without departing from the spirit or main features thereof. For this reason, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The present invention is defined by the claims, and the present invention is not limited to the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

The block diagram which shows the structure of the electronic camera of this embodiment A flowchart showing an example of an operation at the time of photographing by the electronic camera of the present embodiment FIG. 2 is a flowchart for explaining the failed image determination process in S108 of FIG. The figure which shows this book image of the camera shake state typically The figure which shows the result of having extracted the attention area | region from the main image of FIG. The figure which shows the example of a display of the enlarged image corresponding to the main image of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Shooting lens, 12 ... Image sensor, 13 ... Analog processing part, 14 ... Buffer memory, 15 ... Image processing part, 16 ... Image determination part, 17 ... Recording I / F, 18 ... Release button, 19 ... Monitor, 20 ... CPU, 21 ... bus, 22 ... recording medium

Claims (6)

An imaging unit that captures a subject image and generates data of the captured image;
An image determination unit for determining whether the captured image is a failure image;
When the image determination unit determines that the image is a failure image, a display unit that enlarges and displays a partial area of the failure image including a failure point;
An electronic camera comprising: The electronic camera according to claim 1,
The image determination unit performs image analysis on data of the captured image, and determines the captured image as the failed image when the failure location is detected in the image analysis. The electronic camera according to claim 2,
The image determination unit divides the photographed image into a plurality of small regions, performs the image analysis,
The electronic camera is characterized in that the display unit displays an enlarged image of the small area in which the failed part is detected. The electronic camera according to any one of claims 1 to 3,
The camera according to claim 1, wherein the failed image includes a shooting failure caused by any of camera shake, subject blur, red-eye state, and blinking state. The electronic camera according to any one of claims 1 to 4,
An electronic camera, further comprising: an identification data generation unit that associates identification data indicating the failure image with data of the captured image when the image determination unit determines that the image is the failure image . The electronic camera according to claim 5,
The identification data generation unit further includes failure type data indicating a type of shooting failure in the identification data.

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