JP2004312536A - Photographing equipment, blurring detection method of photographing equipment, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect the blurring of a simply photographed image without requiring a sensor etc. and also alleviating a burden on software. <P>SOLUTION: This photographing equipment is provided with a lens optical system 22 which obtains image data of a digital value by photographing an object image, a CCD 23, a sample-and-hold circuit 26 and an A/D converter 27 and a control part 32 which calculates a focus evaluation value from the obtained image data, detects the blurring of the image by comparing focus evaluation values of a plurality of pieces of the calculated image data and performs warning output of generation of the blurring, for example, by a display part 17 according to a detection result. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photographing apparatus suitable for a digital camera or the like, a blur detection method of the photographing apparatus, and a program.
[0002]
[Prior art]
2. Description of the Related Art Recently, digital cameras have become higher in performance and have been significantly reduced in size, so that blurring tends to occur during shooting. Methods for detecting the occurrence of blur generally include a method of directly detecting blur using an acceleration sensor and a method of performing image analysis using software.
[0003]
As a method of performing image analysis with software, for example, a plurality of temporally continuous images including before and after the shutter key operation are acquired corresponding to one shutter key operation, and an image with the smallest “motion degree” is obtained. There is a technology that determines that there is little blurring and records it.
[0004]
(For example, refer to Patent Document 1.)
[0005]
[Patent Document 1]
JP-A-02-172366
[0006]
[Problems to be solved by the invention]
The method of directly detecting blur using the above-described sensor requires at least two calculations corresponding to the vertical and horizontal directions of an image to be mounted in the camera, and has a disadvantage in that the manufacturing cost is increased accordingly.
[0007]
In addition, a method of performing image analysis by software is to calculate the “motion degree” from a plurality of captured images and detect the degree of blurring. Recently, a plurality of image data having a high definition and a large data amount are obtained. Since it is necessary to perform analysis processing after storing in the memory for the number of sheets, not only the processing on software is complicated, but also hardware resources such as a large capacity memory are required, which is a burden in designing a digital camera. It was big.
[0008]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to detect a blur of an image photographed easily without requiring a sensor or the like and also reducing a load on software. It is an object of the present invention to provide a photographing apparatus capable of performing the above, a blur detection method of the photographing apparatus, and a program.
[0009]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a photographing means for photographing a subject image to obtain digital image data, a calculating means for calculating a focus evaluation value from the image data obtained by the photographing means, and a calculating means for calculating the focus evaluation value. And a blur detecting means for comparing the focus evaluation values of the plurality of image data to detect the blur of the image.
[0010]
With such a configuration, if the apparatus performs AF (automatic focusing), image blur is detected based on a change in the calculated focus evaluation value. Also, since the determination can be made on software only by a change of one parameter called a focus evaluation value without using image data, it is possible to detect image blurring very easily.
[0011]
According to a second aspect of the present invention, in the first aspect of the present invention, there is further provided a warning unit for outputting a warning of occurrence of a blur according to a detection result of the blur detection unit.
[0012]
With this configuration, in addition to the operation of the first aspect of the present invention, when a blur is detected, this is warned and the user is made aware of the blur. Move to operation.
[0013]
According to a third aspect of the present invention, in the first aspect of the present invention, there is further provided a shake correcting means for correcting a shake according to a detection result of the shake detecting means.
[0014]
With such a configuration, in addition to the effect of the first aspect of the present invention, it is possible to capture an image in which the generated blur is corrected and the blur is always suppressed.
[0015]
According to a fourth aspect of the present invention, in the second aspect of the present invention, the warning means displays and outputs visual information indicating occurrence of blur.
[0016]
With such a configuration, in addition to the effect of the invention described in claim 2, the occurrence of blurring is displayed and output on a screen of a monitor display unit using a character message, a symbol mark, or the like. In this case, it is possible to immediately recognize this and shift to shooting again.
[0017]
According to a fifth aspect of the present invention, in the second aspect of the present invention, the warning means loudspeaker outputs audio information indicating occurrence of blur.
[0018]
According to such a configuration, in addition to the operation of the invention described in claim 2, the occurrence of blurring is output by, for example, a voice message or a beep sound, so that the user remains in the optical viewfinder. However, it is possible to immediately recognize the occurrence of blurring and shift to shooting again.
[0019]
According to a sixth aspect of the present invention, in the second aspect of the invention, the blur detecting means detects a degree of the blur, and the warning means outputs the degree of the blur detected by the blur detecting means. It is characterized by the following.
[0020]
With such a configuration, in addition to the effect of the invention described in the second aspect, the user himself / herself can determine whether or not to shift to shooting again according to the degree of the generated blur.
[0021]
According to a seventh aspect of the present invention, in the first aspect, the calculating means calculates a focus evaluation value from the image sharpness of the image data.
[0022]
With such a configuration, in addition to the operation of the first aspect of the present invention, blurring can easily occur without adding any other circuit in a general device equipped with a contrast type AF function. Can be detected.
[0023]
According to an eighth aspect of the present invention, in the first aspect of the present invention, the calculating means calculates a focus evaluation value from a plurality of areas in the image data.
[0024]
With such a configuration, in addition to the operation of the first aspect of the present invention, the occurrence of blur can be detected with higher accuracy.
[0025]
According to a ninth aspect of the present invention, in the second aspect of the present invention, a recording unit for recording the image data obtained by the photographing unit, and whether or not the recording of the image data is executed in response to the warning by the warning unit. Instruction means for instructing, and recording control means for controlling whether or not to execute recording of the image data obtained by the photographing means on the recording means in accordance with the contents of the instruction by the instruction means. I do.
[0026]
With such a configuration, in addition to the effect of the second aspect of the present invention, the user can arbitrarily select the recording of an image photographed after warning of the occurrence of blurring.
[0027]
According to a tenth aspect of the present invention, a photographing step of photographing a subject image to obtain digital value image data, a calculating step of calculating a focus evaluation value from the image data obtained in the photographing step, and a calculating step of calculating And a blur detection step of detecting the blur of the image by comparing the focus evaluation values of the plurality of pieces of image data.
[0028]
According to such a method, if the apparatus performs AF, the blur of the image is detected from the change of the calculated focus evaluation value, so that not only the sensor and the like are not required but also the software Since the determination can be made only by a change of one parameter called the focus evaluation value without using data, it is possible to detect image blurring very easily.
[0029]
According to an eleventh aspect of the present invention, there is provided a program to be executed by a computer built in a photographing apparatus, comprising: a photographing step of photographing a subject image to obtain digital value image data; The computer is characterized by causing a computer to execute a calculation step of calculating a focus evaluation value and a blur detection step of comparing the focus evaluation values of a plurality of pieces of image data calculated in the calculation step and detecting a blur of an image.
[0030]
With such a program content, a device that performs AF always detects a blur of an image from a change in a calculated focus evaluation value, so that not only a sensor and the like are not required but also software Since the determination can be made only by the change of one parameter called the focus evaluation value without using the image data, it is possible to detect the blur of the image very easily.
[0031]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment in which the present invention is applied to a digital camera having a contrast AF function will be described below with reference to the drawings.
[0032]
FIG. 1 is a perspective view showing the external configuration, in which FIG. 1 (A) mainly shows the configuration on the front side and FIG. 1 (B) shows the configuration mainly on the back side.
[0033]
In this digital camera 1, a photographic lens 2, a self-timer lamp 3, an optical finder window 4, a microphone unit 5, a strobe light emitting unit 6, and a rubber grip 7 are disposed on a front surface of a substantially rectangular thin plate-like body. A power key 8 and a shutter key 9 are arranged on the right end side (for the user).
[0034]
The rubber grip 7 is made of rubber which is disposed so that the right middle finger, ring finger, and little finger can securely grip the housing when the user holds the digital camera 1 with the right hand from the right side of the housing during shooting. It is a band-like projection.
[0035]
A power key 8 is a key operated every time the power is turned on / off, and a shutter key 9 instructs a shooting timing in a shooting mode.
[0036]
On the back of the digital camera 1, a mode switch (SW) 10, a speaker unit 11, a menu key 12, a cross key 13, a set key 14, an optical finder 15, a strobe charge lamp 16, and a display unit 17 are arranged.
[0037]
The mode switch 10 is configured by, for example, a slide key switch, and switches between a recording mode “R” and a reproduction mode “P” which are basic modes.
[0038]
The menu key 12 is operated when selecting various menu items and the like.
[0039]
The cross key 13 is integrally formed with keys for moving a cursor in up, down, left, and right directions, and is operated when moving a displayed menu item or the like.
[0040]
The set key 14 is arranged at the center position of the cross key 13 and is operated to set the contents of the menu item selected at that time.
[0041]
The strobe charge lamp 16 is an LED lamp disposed close to the optical finder 15, and is used when the user of the digital camera 1 is looking into the optical finder 15 or when viewing the display unit 17. Even so, the charge state of the strobe and the like are visually recognized by the user.
[0042]
The display unit 17 is configured by a color liquid crystal panel with a backlight, and performs monitor display of a through image as an electronic finder in a recording mode, and reproduces and displays a selected image or the like in a reproduction mode.
[0043]
Although not shown, on the bottom surface of the digital camera 1, for example, a USB (Universal) is provided as a memory card slot for attaching and detaching a memory card used as a recording medium and a serial interface connector for connecting to an external personal computer or the like. Serial Bus) connector and the like are provided.
[0044]
Next, the electronic circuit configuration of the digital camera 1 will be described with reference to FIG.
In the same figure, in the recording mode which is the basic mode, the focus position and the aperture position are moved by driving the motor (M) 21 and disposed behind the photographing optical axis of the lens optical system 22 constituting the photographing lens 2. The CCD 23, which is an image pickup device, is scanned and driven by a timing generator (TG) 24 and a vertical driver 25, and outputs a photoelectric conversion output corresponding to a light image formed at regular intervals for one screen.
[0045]
The photoelectric conversion output is appropriately adjusted in gain for each of RGB primary color components in the state of an analog value signal, sampled and held by a sample and hold circuit 26, converted to digital data by an A / D converter 27, and converted into color data. A color process including a pixel interpolation process and a γ correction process is performed in the process circuit 28, and a digital luminance signal Y and color difference signals Cb and Cr are generated, and are output to a DMA (Direct Memory Access) controller 29.
[0046]
The DMA controller 29 converts the luminance signal Y and the color difference signals Cb and Cr output from the color process circuit 28 into the DMA controller 29 once using the composite synchronizing signal, the memory write enable signal, and the clock signal from the color process circuit 28. And a DMA transfer is performed to a DRAM 31 used as a buffer memory via a DRAM interface (I / F) 30.
[0047]
The control unit 32 includes a CPU, a ROM fixedly storing an operation program executed by the CPU including a shake detection process in a recording mode described later, a RAM used as a work memory, and the like. After the DMA transfer of the luminance and chrominance signals to the DRAM 31, the luminance and chrominance signals are read out from the DRAM 31 via the DRAM interface 30 and written into the VRAM 34 via the VRAM controller 33. Put in.
[0048]
The digital video encoder 35 periodically reads out the luminance and color difference signals from the VRAM 34 via the VRAM controller 33, generates a video signal based on the data, and outputs the video signal to the display unit 17.
[0049]
The display unit 17 functions as a monitor display unit (electronic finder) in the recording mode as described above, and performs a display based on the video signal from the digital video encoder 35, so that the VRAM controller 33 can acquire the display at that time. An image based on the embedded image information is displayed in real time.
[0050]
When the shutter key 9 constituting the key input unit 36 is operated at a timing at which the user wants to take a still image while the image at that time is displayed on the display unit 17 in real time as a monitor image, a trigger signal is generated. Occurs.
[0051]
The control unit 32 stops the path from the CCD 23 to the DRAM 31 immediately after the completion of the DMA transfer of the luminance and color difference signals for one screen taken from the CCD 23 to the DRAM 31 at that time in response to the trigger signal, Transit to the record save state.
[0052]
In this recording and storage state, the control unit 32 transmits the luminance and chrominance signals for one frame written in the DRAM 31 via the DRAM interface 30 to each of the Y, Cb, and Cr components by 8 pixels by 8 pixels. Is written in a unit called a basic block of JPEG (Joint Photograph Coding Experts Group) circuit 37, and the JPEG circuit 37 is an adaptive discrete cosine transform (ADCT) and entropy coding system. Data compression by processing such as conversion.
[0053]
Then, the obtained code data is read out from the JPEG circuit 37 as a data file of one image, and the memory card 38 which is removably mounted as a recording medium of the digital camera 1 or is fixedly incorporated in the digital camera 1. The data is written into one of the built-in memories 39.
[0054]
Then, with the compression processing of the luminance and chrominance signals for one frame and the completion of the writing of all the compressed data to the memory card 38 or the built-in memory 39, the control unit 32 activates the path from the CCD 23 to the DRAM 31 again.
[0055]
The control unit 32 is further connected to an audio processing unit 40, a USB interface (I / F) 41, and a flash drive unit 42.
[0056]
The sound processing unit 40 includes a sound source circuit such as a PCM sound source. When recording a sound, the sound processing unit 40 digitizes the sound signal input from the microphone unit (MIC) 5 and converts the sound signal into a predetermined data file format, for example, an MP3 (MPEG-1 audio layer). 3) Create an audio data file by data compression in accordance with the standard and send it to the memory card 38 or the built-in memory 39, while compressing the audio data file sent from the memory card 38 or the built-in memory 39 when playing back the sound. The analog signal is converted into an analog signal, and the loudspeaker (SP) 11 is driven to emit a loudspeaker.
[0057]
The USB interface 41 performs communication control when transmitting and receiving image data and the like to and from another information terminal device such as a personal computer connected by wire through a USB connector.
[0058]
The strobe driving unit 42 flashes the strobe light emitting unit 6 based on the control from the control unit 32 after charging a large-capacity strobe capacitor (not shown) at the time of capturing a still image.
[0059]
The key input unit 36 includes the power key 8, the mode switch 10, the menu key 12, the cross key 13, the set key 14, and the like in addition to the shutter key 9 described above. This signal is sent directly to the control unit 32.
[0060]
However, at the time of shooting a moving image instead of a still image, a memory card of a still image data file obtained by compressing the still image data by the JPEG circuit 37 while the shutter key 9 of the key input unit 36 is continuously operated. 38 or the recording to the built-in memory 39 is executed continuously in time, and when the operation of the shutter key 9 is completed, or when a predetermined time limit, for example, 30 seconds has elapsed, the series of still image data files is stored. Collectively reset as a motion JPEG data file.
[0061]
Also, in the reproduction mode which is the basic mode, the control unit 32 selectively reads out the image data recorded in the memory card 38 or the built-in memory 39, and the procedure completely reverses the procedure in which the JPEG circuit 37 compresses the data in the recording mode. The compressed image data is decompressed, and the decompressed image data is stored in the DRAM 31 via the DRAM interface 30. The stored content of the DRAM 31 is stored in the VRAM 34 via the VRAM controller 33. The image data is periodically read out to generate a video signal, and the display unit 17 reproduces and outputs the video signal.
[0062]
If the selected image data is not a still image but a moving image, the individual still image data constituting the selected moving image file is played back continuously in time, and the playback of all still image data ends. At this point, reproduction and display are performed using only the still image data located at the head until the next reproduction instruction is issued.
[0063]
Next, the operation of the above embodiment will be described.
The following processes are basically executed by the control unit 32 based on a program fixedly stored in advance.
[0064]
FIG. 3 shows the contents of processing in the recording mode. At first, the process waits until the shutter key 9 of the key input unit 36 is half-pressed (step A01).
[0065]
That is, the shutter key 9 detects a pressing operation with a two-stage stroke, locks the photographing condition in the first-stage operation, so-called half-pressed state, and actually locks in the second-stage operation, so-called full-press state. Is performed.
[0066]
When the shutter key 9 is half-pressed, this is determined in step A01, AF processing is performed to obtain a focus position, and at the same time a focus evaluation value is obtained (step A02), then AE (automatic exposure) An aperture value and a shutter speed for obtaining an appropriate exposure are obtained by the processing (step A03), and the photographing conditions are locked.
[0067]
FIG. 4 illustrates the focus evaluation value obtained during the AF processing. When a focusing lens among a plurality of lenses constituting the lens optical system 22 is moved, the sharpness (contrast value) of the obtained image is set to the apex position at the apex and becomes lower as the focus position deviates. Therefore, for the image obtained at that time, the position where the contrast value becomes highest by moving the focusing lens is set as the focus position, and the contrast value is acquired and held as the focus evaluation value of the image. It is.
[0068]
By repeatedly determining whether or not the shutter key 9 is fully pressed (step A04) and whether or not the shutter key 9 is still half-pressed (step A05) from the state in which the photographing conditions are locked, the shutter is released. While confirming that the key 9 is half-pressed, it waits until the key 9 is fully pressed.
[0069]
Here, when the half-pressed state of the shutter key 9 is released, this is determined in step A05, the lock of the shooting condition is unlocked, and the process returns to step A01 again.
[0070]
Then, when the shutter key 9 is fully pressed, this is determined in step A04, and the state shifts to the image data recording / saving state. That is, after obtaining image data by imaging (step A06), a contrast value as a focus evaluation value is obtained from the obtained image data as in the case of step A02 (step A07).
[0071]
Next, the focus evaluation value obtained from the photographed image is compared with the focus evaluation value obtained at the time of the AF processing in step A02 as a reference, and it is determined whether or not blur has occurred depending on whether or not the focus evaluation value is within a predetermined range. (Step A08).
[0072]
When it is determined that the focus evaluation value obtained from the photographed image is out of the predetermined range with respect to the focus evaluation value obtained at the time of the AF processing and blur has occurred, a warning message indicating that blur has occurred is issued. For example, after displaying and outputting on the display unit 17 (step A09), the image data obtained by shooting is filed and stored in the memory card 38 or the built-in memory 39 (step A10). Then, the process returns to step A01 to prepare for the next photographing again.
[0073]
The display of the warning message indicating that the blur has occurred may be performed after recording and saving (step A10).
[0074]
If it is determined in step A08 whether or not blur has occurred, and if it is determined that blur has occurred, blur correction may be performed instead of displaying a warning message in step A09. Good. In this case, the blur correction may be performed using a technique generally used in image processing or the like, and the details thereof will not be described herein.
[0075]
By performing the blur correction in this way, even when the captured image is blurred, the user can automatically record the image in which the blur is suppressed without concern.
[0076]
FIG. 5 illustrates a blur warning message displayed on the display unit 17 in step A09.
FIG. 5A shows an example centered on the text message “blur warning!”. The text message is displayed on the display unit 17 by superimposing the text message on the captured image, and the Is visually warned to the user.
FIG. 5B illustrates a person and a symbol imitating the fluctuation of the person. The symbol is superimposed on the captured image and displayed on the display unit 17 as in FIG. 5A. This visually warns the user that the blur has occurred.
[0077]
If it is determined in step A08 that the focus evaluation value obtained from the captured image is within a predetermined range with respect to the focus evaluation value obtained at the time of the AF processing, and that no blurring has occurred, By omitting the processing of step A09, the image data obtained by the photographing is filed as it is, and recorded and saved in the memory card 38 or the built-in memory 39 (step A10). The process returns to step A01 to prepare for the next photographing again.
[0078]
As described above, if the camera performs AF, the image blur is detected from the change of the calculated focus evaluation value, so that dedicated sensors such as an acceleration sensor for detecting the blur are not required. Not only that, but also on software, the determination can be made based on only a change of one parameter called a focus evaluation value without using image data, and therefore, image blur can be detected extremely easily.
[0079]
In particular, since a camera that performs AF of a contrast method calculates an in-focus evaluation value from the image sharpness of image data, it does not originally require sensors for AF as a camera that performs AF of an active method. The present invention can be applied to shake detection while keeping the configuration of the camera simple.
[0080]
Further, in the above-described embodiment, the occurrence of blur due to a character message, a symbol mark, or the like is displayed and output on the display unit 17. Therefore, even if a blur occurs, the user can immediately recognize the blur and shift to shooting again.
[0081]
In the above-described embodiment, the description has been given assuming that the display unit 17 displays a character message, a symbol mark, and the like accompanying the detection of a shake. However, the present invention is not limited to this. Lighting driving may be performed in a color or blinking pattern, or furthermore, not limited to a visual warning, and may be output from a speaker unit 11 as a voice message or a beep sound.
[0082]
In this case, even when the user of the digital camera 1 is looking into the optical viewfinder 15 without using the display unit 17 for displaying the through image on the monitor, the detection of the blur can be recognized.
[0083]
Further, in the processing content in the recording mode shown in FIG. 3, it has been described that the image data obtained by the photographing is recorded in the memory card 38 or the built-in memory 39 regardless of whether or not the blur is detected. Alternatively, when occurrence of blurring is detected during image capturing, whether or not to record the image data may be left to the user's judgment.
[0084]
Hereinafter, another operation example of the present embodiment will be described with reference to FIG.
In the case of FIG. 6, since the operation contents are completely the same up to step A08 in FIG. 3, the same steps are denoted by the same reference numerals and the description of the processing contents up to step S08 is omitted.
[0085]
However, if it is determined in step A08 that the focus evaluation value obtained from the captured image is out of the predetermined range with respect to the focus evaluation value obtained at the time of the AF processing, and that blurring has occurred, blurring has occurred. For example, a warning message as shown in FIG. 5 (A) or FIG. 5 (B) is output and displayed on the display unit 17 and
"The captured image may be blurred
Do you want to record images?
Yes, No"
A message prompting the user to select the presence or absence of a record is displayed using a text message such as “”. On the other hand, for example, the operation of responding to the selection after the “Yes” side is highlighted as a tentative selection state (step A11). The process waits for the execution (Step A12).
[0086]
Then, when it is determined that a response operation has been performed, it is next determined whether or not the recording is approved based on the operation content (step A13).
[0087]
Here, if it is determined that the “No” side has been selected as the response operation to the text message, the shooting and recording operations corresponding to the operation of the shutter key 9 at that time are performed in response to the operation. The process is interrupted, and the process returns to step A01.
[0088]
If it is determined in step A13 that the "yes" side has been selected as the response operation to the text message, the image data obtained by shooting is filed and stored in the memory card 38 or the built-in memory 39. (Step A10) The above-described series of processes related to photographing are completed, and the process returns to step A01 to prepare for the next photographing.
[0089]
If it is determined in step A08 that the focus evaluation value obtained from the captured image is within a predetermined range with respect to the focus evaluation value obtained at the time of the AF processing, and that no blurring has occurred, By omitting the processing of steps A11 to A13, the image data obtained by the shooting is directly converted into a file and recorded and stored in the memory card 38 or the built-in memory 39 (step A10). Then, the process returns to the process from step A01 to prepare for the next photographing again.
[0090]
As described above, in addition to the effect on the operation described in the processing contents of FIG. 3 described above, when blurring during shooting is detected, the fact is notified and notified, and then whether or not to execute recording is left to the user. As a result, the user can arbitrarily select to record an image captured.
[0091]
In the above-described embodiment, the focus evaluation value obtained from the captured image is simply compared with the focus evaluation value obtained at the time of the AF processing in step A02, and the blur is determined based on whether the focus evaluation value is within a predetermined range. Although it has been described that it is determined whether or not the blur has occurred, instead of performing the processing corresponding to the presence or absence of the blur alternatively, the degree of the blur is displayed on the display unit 17 and the May be selected to determine whether or not recording is performed.
FIG. 7 shows a display example of such a bar graph BG on the display unit 17, in which the lower left end of the screen is obtained from the photographed image based on the focus evaluation value obtained during the AF processing. Since the focus evaluation value is only about 1/3, and the contrast is greatly reduced, it indicates that there is a great concern about occurrence of blur.
[0092]
By notifying and outputting the specific degree of occurrence of the blur as described above, the user himself / herself can determine whether or not to shift to shooting again in accordance with the degree of the generated blur.
[0093]
Further, as described above, the detection of blur is calculated from the focus evaluation value. The focus evaluation value is calculated using only the “spot AF” calculated only from the center area of the image, or the focus area is determined by focusing on the center area. May be based on “center-weighted AF”, which is calculated in consideration of the area described above, or may be based on “multi-point AF”, which mainly detects a plurality of predetermined areas in an image.
[0094]
FIG. 8 illustrates a case where a total of three focus areas are arranged on the left and right sides of the focus area AFA with the center of the image interposed therebetween. AF processing is executed at each of the three places, and the closest AF processing is performed. The focus evaluation value in the area AFA at a distance is selected, and is used as the overall focus evaluation value.
[0095]
As described above, by calculating the focus evaluation value from a plurality of regions, accurate AF processing can be performed corresponding to various compositions, and as a result, the occurrence of blur can be detected with higher accuracy. Also leads to.
[0096]
Further, in the above embodiment, the focus evaluation value obtained at the time of the AF processing is compared with the focus evaluation value obtained at the time of shooting, and it is determined whether or not blur has occurred depending on whether or not the focus evaluation value is within a predetermined range. For example, in a through image captured from a CCD after shooting, the shutter key is pressed halfway to obtain a focus evaluation value, and the focus evaluation values before and after shooting are compared. It may be determined whether or not the error has occurred.
[0097]
By comparing the focus evaluation values a plurality of times in this way, the occurrence of blur can be detected with higher accuracy.
[0098]
Although the above-described embodiment is applied to a digital camera, the present invention is not limited to this, and a mobile phone or a PDA (Personal Digital Assistant: personal digital assistant) having a camera function for performing AF processing is provided. Similarly, the present invention can be applied to portable information terminals).
[0099]
In addition, the present invention is not limited to the above-described embodiment, and can be variously modified and implemented without departing from the gist thereof.
[0100]
Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent features. For example, even if some components are deleted from all the components shown in the embodiments, at least one of the problems described in the column of the problem to be solved by the invention can be solved and the effects described in the column of the effect of the invention can be solved. When at least one of the effects described above is obtained, a configuration from which this component is deleted can be extracted as an invention.
[0101]
【The invention's effect】
According to the first aspect of the present invention, if the apparatus performs AF (automatic focusing), the image blur is detected from a change in the calculated focus evaluation value, so that a sensor or the like is not required. Instead, it is possible to judge only by a change of one parameter called a focus evaluation value without using image data on software, so that image blur can be detected very easily.
[0102]
According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, when a blur is detected, a warning is given to the user to recognize the blur, so that the user can immediately take a picture again. Then, it is possible to shift to a coping operation.
[0103]
According to the third aspect of the invention, in addition to the effect of the first aspect of the invention, it is possible to capture an image in which the generated blur is corrected and the blur is always suppressed.
[0104]
According to the fourth aspect of the present invention, in addition to the effect of the second aspect of the present invention, for example, the occurrence of blurring is displayed and output on a screen of a monitor display unit by a text message or a symbol mark. Even when the image is generated, it is possible to visually recognize this immediately and shift to photographing again.
[0105]
According to the fifth aspect of the invention, in addition to the effect of the second aspect of the invention, since the occurrence of blurring is output by, for example, a voice message or a beep sound, the user remains in the optical viewfinder. In this state, it is possible to immediately recognize the occurrence of blurring and shift to shooting again.
[0106]
According to the invention described in claim 6, in addition to the effect of the invention described in claim 2, the user himself / herself can determine whether or not to shift to shooting again in accordance with the degree of blurring that has occurred.
[0107]
According to the seventh aspect of the present invention, in addition to the effect of the first aspect of the present invention, a general apparatus equipped with a contrast type AF function can easily shake without adding any other circuit or the like. Occurrence can also be detected.
[0108]
According to the invention of claim 8, in addition to the effect of the invention of claim 1, the occurrence of blur can be detected with higher accuracy.
[0109]
According to the ninth aspect of the present invention, in addition to the effect of the second aspect of the present invention, it is possible to select the recording of an image arbitrarily shot by the user after warning of the occurrence of the blur.
[0110]
According to the tenth aspect of the present invention, if the apparatus performs AF, the image blur is detected from a change in the calculated focus evaluation value, so that not only the sensor is not required but also the software is used. Can be determined only by a change in one parameter called a focus evaluation value without using image data, so that blurring of an image can be detected very easily.
[0111]
According to the eleventh aspect of the present invention, if the apparatus performs AF, the image blur is detected from the change of the calculated focus evaluation value, so that not only the sensor is not required but also the software Can be determined only by a change in one parameter called a focus evaluation value without using image data, so that blurring of an image can be detected very easily.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an external configuration of a digital camera according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of an electronic circuit according to the embodiment.
FIG. 3 is a flowchart showing still image shooting processing in a recording mode according to the embodiment;
FIG. 4 is an exemplary view showing a display screen at the time of a shake detection warning according to the embodiment;
FIG. 5 is an exemplary view showing a blur warning message displayed on the screen according to the embodiment;
FIG. 6 is a flowchart showing another processing content of still image shooting in the recording mode according to the embodiment;
FIG. 7 is an exemplary diagram showing a display example of the degree of blurring generated on the display unit according to the embodiment;
FIG. 8 is a view showing an example of the arrangement of a plurality of focus areas according to the embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Digital camera, 2 ... Shooting lens, 3 ... Self-timer lamp, 4 ... Optical finder window, 5 ... Microphone unit (MIC), 6 ... Strobe light emitting unit, 7 ... Rubber grip, 8 ... Power key, 9 ... Shutter key , 10 mode switch (SW), 11 speaker unit (SP), 12 menu key, 13 cross key, 14 set key, 15 optical finder, 16 strobe charge lamp, 17 display unit, 21 Motor (M), 22: Lens optical system, 23: CCD, 24: Timing generator (TG), 25: Vertical driver, 26: Sample / hold circuit (S / H), 27: A / D converter, 28: Color process circuit, 29 DMA controller, 30 DRAM interface (I / F), 31 DRAM, 32 controller, 33 VRAM controller , VRAM, 35 digital video encoder, 36 key input unit, 37 JPEG circuit, 38 memory card, 39 internal memory, 40 audio processing unit, 41 USB interface (I / F), 42: Strobe drive unit, AFA: Focus area, BG: Bar graph.

Claims (11)

Photographing means for photographing a subject image to obtain digital value image data;
Calculating means for calculating a focus evaluation value from image data obtained by the photographing means;
An image-capturing apparatus comprising: a blur detection unit configured to compare a focus evaluation value of a plurality of image data calculated by the calculation unit and detect a blur of an image. 2. The photographing apparatus according to claim 1, further comprising a warning unit that outputs a warning of occurrence of a blur according to a detection result of the blur detection unit. 2. The photographing apparatus according to claim 1, further comprising: a shake correcting unit that performs shake correction in accordance with a detection result of the shake detecting unit. 3. The photographing apparatus according to claim 2, wherein said warning means displays and outputs visual information indicating occurrence of blur. 3. The photographing apparatus according to claim 2, wherein the warning unit outputs voice information indicating occurrence of blurring. The blur detecting means detects a degree of blur,
3. The photographing apparatus according to claim 2, wherein the warning unit outputs the degree of blur detected by the blur detection unit. 2. The photographing apparatus according to claim 1, wherein said calculating means calculates a focus evaluation value from an image sharpness of the image data. 2. The photographing apparatus according to claim 1, wherein said calculating means calculates a focus evaluation value from a plurality of regions in the image data. Recording means for recording image data obtained by the photographing means,
Instruction means for instructing whether or not to execute recording of image data in response to the warning by the warning means,
3. A recording control unit according to claim 2, further comprising a recording control unit for controlling whether or not to execute recording of the image data obtained by said photographing unit on said recording unit in accordance with the contents of said instruction unit. Shooting equipment. A photographing step of photographing a subject image to obtain digital value image data;
A calculating step of calculating a focus evaluation value from the image data obtained in the photographing step;
A blur detection step of comparing focus evaluation values of a plurality of image data calculated in the calculation step and detecting blur of the image. A program to be executed by a computer built in the imaging device,
A photographing step of photographing a subject image to obtain digital value image data;
A calculating step of calculating a focus evaluation value from the image data obtained in the photographing step;
A computer-readable storage medium storing a program for causing a computer to execute a blur detection step of detecting a blur of an image by comparing focus evaluation values of a plurality of image data calculated in the calculation step.

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