JP2009244490A - Camera, camera control program and camera control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a shake correcting function act appropriately according to a user. <P>SOLUTION: A shake amount evaluated value until previous time corresponding to a photographing condition is read out (step S110). Specifically, in a step S103, when a person is selected as a photographic scene or a subject, and a photographing condition of a photographing condition setting data memory corresponding thereto is set, and also a user A is set, user A's shake amount evaluated value is read out from a user's camera shake result data memory. Whether or not the read-out shake evaluated value of the photographing condition for the user is equal to or above a prescribed value is determined (step S111). When it is determined as NO, and the shake evaluated value of the photographing condition for the user is under the prescribed value, a camera shake correction function is set to OFF. When the shake evaluated value of the photographing condition is equal to or above the prescribed value, the camera shake correction function is set to ON (step S113). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a camera that captures an image of a subject and records it as a still image, a control program for the camera, and a camera control method.

Conventionally, in scenes and shooting conditions that increase camera shake (dark subjects, long exposure times, long focal lengths, close-up macro shooting, when not using a tripod), the camera automatically switches to shake reduction mode, Various cameras that change the correction parameters have been proposed (see Patent Documents 1, 2, and 3).
Japanese Patent Laid-Open No. 03-170919 JP 2003-280059 A JP 2004-361486 A

  However, in such a conventional camera, whether or not blur correction is performed and the control details of the blur correction are determined regardless of the skill level of each user and the degree of camera shake. For this reason, depending on the user, there is a problem that the blur correction is insufficient or, conversely, the processing time and the processing load increase due to unnecessary blur correction.

  The present invention has been made in view of such conventional problems, and an object thereof is to provide a camera capable of appropriately executing a blur correction function at the time of shooting, a control program for the camera, and a camera control method. To do.

  In order to solve the above-mentioned problem, the invention described in claim 1 is a photographing means, a blur correcting means for correcting a blur of an image photographed by the photographing means, a blur detecting means for detecting a blur of the camera body, and the blur detection. Blur information storage means for storing blur information indicating blur of the camera body detected by the means in correspondence with shooting conditions set for the camera, and the blur information according to the shooting conditions set for the camera. The image processing apparatus includes: an acquisition unit that acquires corresponding blur information from the storage unit; and a control unit that controls the operation of the blur correction unit based on the blur information acquired by the acquisition unit.

  Further, the invention according to claim 2 is the invention according to claim 1, wherein the control means should correct blurring of an image photographed by the photographing means based on the blur information obtained by the obtaining means. It is characterized in that there is provided a judging means for judging whether or not the blur correction means is operated or stopped according to the judgment result of the judging means.

The invention according to claim 3 is the invention according to claim 1, wherein the control means is
A blur amount determining unit configured to determine whether or not a blur amount indicated by the blur information acquired by the acquiring unit is equal to or greater than an allowable blur amount, and the blur correction unit is configured according to a determination result of the blur amount determining unit; It is characterized by operating or stopping.

  According to a fourth aspect of the present invention, in the first, second, or third aspect of the invention, the blur correction unit is a blur correction mechanism that drives an optical system included in the photographing unit.

  According to a fifth aspect of the invention, in the first aspect of the invention, the blur correction unit is an image correction unit that corrects an image captured by the photographing unit.

  According to a sixth aspect of the present invention, in the invention according to any one of the first to fifth aspects, the blur information storage unit is detected by the blur detection unit each time shooting is performed by the shooting unit. Further, the blur information is updated based on the blur of the camera body.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein the blur information storage means stores the blur information together with information indicating a user of the camera. Features.

  According to an eighth aspect of the present invention, there is provided a computer having a camera including a photographing unit, a blur correcting unit that corrects a blur of an image captured by the photographing unit, and a blur detecting unit that detects a blur of the camera body. According to the blur information storage means for storing blur information indicating the blur of the camera body detected by the blur detection means in correspondence with the shooting conditions set in the camera, and according to the shooting conditions set in the camera, It is characterized by functioning as acquisition means for acquiring corresponding blur information from the blur information storage means and control means for controlling the operation of the blur correction means based on the blur information acquired by the acquisition means.

  The invention described in claim 9 is a camera control method comprising a photographing unit, a blur correcting unit for correcting blur of an image photographed by the photographing unit, and a blur detecting unit for detecting blur of the camera body. A blur information storing step for storing blur information indicating blur of the camera body detected by the blur detection unit in a storage unit in association with a shooting condition set in the camera, and shooting set in the camera An acquisition step of acquiring corresponding blur information from the storage unit according to conditions, and a control step of controlling the operation of the blur correction unit based on the blur information acquired by the acquisition unit step. And

  According to the present invention, it is possible to execute an appropriate blur correction function according to shooting conditions. Accordingly, the blur correction function can be appropriately executed without causing an increase in processing time until photographing due to unnecessary execution of the blur correction function and an increase in processing load on the apparatus main body.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(First embodiment)
1A is a front view of a digital camera 1 common to each embodiment, FIG. 1B is a side perspective view, and FIG. 2 is a rear view. The main body 2 of the digital camera 1 is provided with a release button (shutter switch) 3 and a power switch 4 having a half-press function on the upper surface portion, and a grip portion 5, a strobe 6 and an image pickup device on the front portion. A light receiving window 7 of the lens unit is arranged. Also, on the back side, a mode changeover switch 8 for switching between a shooting mode and a playback mode, a zoom operation key 9, a cursor key 10, a determination / OK key 11, and a DISP key which is also used as an on / off key for displaying a shake amount 12, a menu key 13 and a display unit 14 including an LCD that also functions as an electronic viewfinder are arranged. The display unit 14 displays a blur amount display unit 14a according to the mode. Further, as shown in FIG. 1B, a first angular velocity sensor 16 for detecting a vertical angular velocity and a second angular velocity sensor 17 for detecting a horizontal angular acceleration are disposed inside. A rotary mirror 18, a lens group 19, an image sensor 20, and the like are arranged.

  3A is a front view of the rotary mirror 18, and FIG. 3B is a side view. The rotary mirror 18 is a rotary mirror using an electromagnetic voice coil, and is provided at a Yaw rotary gimbal 182 whose upper and lower central parts are fixed to a vertical Yaw rotary shaft 181 and at the left and right central parts of the Yaw rotary gimbal 182. A Pitch rotation shaft 183 and a Pitch rotation gimbal 184 disposed in the Yaw rotation gimbal 182 are provided with the center of both sides fixed to the Pitch rotation shaft 183, and a mirror 185 is disposed on the Pitch rotation gimbal 184. Yes. Then, the mover moves linearly in the left-right direction by a rack and pinion (not shown) provided between the mover of the YCM VCM (voice coil motor) actuator 186 and the Yaw rotation shaft 181, so that the Yaw rotation gimbal 182 Is driven to rotate about the Yaw rotation shaft 181. Further, the mover moves vertically in a vertical direction by a rack and pinion (not shown) provided between the mover of the pitch driving VCM actuator 187 and the pitch rotation shaft 183, so that the pitch rotation gimbal 184 is moved to the pitch rotation shaft 183. It is comprised so that it may be rotationally driven centering on.

  FIG. 4 is a block diagram showing a specific circuit configuration of the digital camera 1. In the figure, the operation unit 23 is configured by the switches and key groups shown in FIGS. 1 and 2 such as the release button 3 and the power switch 4, and operation information of the switches and key groups is input via an input circuit 24. Is input to the control unit 25. The control unit 25 is a microcomputer including a CPU and its peripheral circuits, a RAM that is a working memory of the CPU, and the like, and controls each unit.

  The control unit 25 includes a display memory 26, a display drive block 27, an image buffer memory 28, an image signal processing unit 29, a compression encoding / decompression decoding unit 30, a still image / moving image memory 31, a clock circuit 70, a program A memory 32, a data memory 33, a memory IF 34, an external I / O interface 35, a communication control block 36, a power supply control block 37, and a photographing control unit 38 are connected. The display memory 26 temporarily stores various display data displayed on the display unit 14. The display drive block 27 drives the display unit 14, and the image buffer memory 28 temporarily stores the image data when processing it.

  The image signal processing unit 29 is a DSP that executes various processes on an image signal taken in by the control unit 25 from an image sensor described later. The compression encoding / decompression decoding unit 30 decompresses the image data processed by the image signal processing unit at the time of recording, and decompresses and decodes the recorded image data at the time of reproduction. The still image / moving image memory 31 records and saves image data (still image data) captured by operating the release button 3. The clock circuit 70 measures the current time and supplies it to the control unit 25. The program memory 32 includes a control program of the control unit 25 shown in a flowchart to be described later, a shooting control program for each shooting scene such as “person shooting mode” and “night scene shooting mode”, target subject type information for each shooting scene, the target Feature amount data corresponding to the type of subject is stored.

  The data memory 33 includes a scene-specific shooting condition setting data memory 331, a user's camera shake result data memory 332, and a camera shake correction setting data memory 333. The memory IF 34 is connected to a removable external memory medium 39. The external I / O interface 35 is connected to the USB connector 40, the communication control block 36 is connected to the antenna 42 via the wireless LAN transmission / reception unit 41, and the battery 43 is connected to the power control block 37. The electric power from the battery 43 is supplied to each unit via the power control block 37 and the control unit 25.

  The photographing control unit 38 is connected to each irradiation drive unit 44 for driving the irradiation angle of the strobe 6 and a strobe illumination driving unit 45 for driving the irradiation. The light receiving angle driving unit 47 to be driven, the color temperature detecting unit 48 for detecting and outputting the color temperature from the photometric / ranging sensor 46, the photometric unit 49 for detecting and outputting the photometric data, and the distance measuring data are detected and output. A distance measuring unit 50 is connected. Furthermore, the first and second angular velocity sensors 17 and 17 are connected to the photographing control unit 38 via angular velocity detectors 51 and 52 and integrators 53 and 54, respectively.

  On the other hand, the zoom lens unit 55 is provided with the rotary mirror 18, the lens group 19, and the image pickup device 20, and a drive mechanism 56 that rotates the rotary mirror 18 and is inserted into the lens group 19. A diaphragm 57 is provided, and a shutter 58 is disposed in front of the image sensor 20.

  Further, the photographing control unit 38 includes an electric mirror Y direction driving unit 59, an electric mirror X direction driving unit 60, a focus lens driving unit 61, a zoom lens driving unit 62, an aperture driving unit 63, a shutter driving unit 64, and a video signal. A processing unit 65 and a timing control & driver 66 are connected. The electric mirror Y direction drive unit 59 drives the drive mechanism 56 to operate the rotary mirror 18 in the vertical direction, and the electric mirror X direction drive unit 60 operates in the left and right direction. The focus lens driving unit 61 drives the focus lens in the lens group 19, and the zoom lens driving unit 62 zooms in the lens group 19 to enlarge or reduce the subject image in accordance with the operation of the zoom operation key 9. The lens is driven. The aperture driving unit 63 drives the aperture 57, and the shutter driving unit 64 drives the shutter 58. The video signal processor 65 is supplied with an A / D circuit that converts an analog signal from the image sensor 20 into a digital signal, a CDS that holds the digital image signal from the A / D circuit, and an image signal from the CDS. It consists of a gain adjustment amplifier (AGC), which is an analog amplifier.

  FIG. 5 is a conceptual diagram showing configurations of the scene-specific shooting condition setting data memory 331 and the user's camera shake result data memory 332. The scene-specific shooting condition setting data memory 331 stores sample images and shooting condition setting data (scene-specific shooting program) according to the shooting scene or subject such as “person” or “landscape”. The shooting condition setting data includes EV shift (exposure correction), strobe, white balance, ISO sensitivity, etc. In addition, the user's camera shake result data memory 332 includes, for each piece of information indicating the user, such as the user A, the user B, and the user C, the acceleration sensors 51, The blur amount in the vertical direction and the horizontal direction of the digital camera 1 detected by the user in 52 is updated and recorded.

  FIG. 6 is a flowchart showing the processing procedure of the present embodiment. When the control unit 25 controls each unit based on the program stored in the program memory 32, the digital camera 1 operates as shown in this flowchart. First, it is determined whether or not a shooting mode has been set by a user operation on the operation unit 23 (step S101). If the shooting mode is not set and another mode is set, other mode processing is executed according to the set mode (step S102).

  When the shooting mode is set, the shooting condition setting data (by scene) stored in the shooting condition setting data memory 331 is selected according to the shooting scene or subject selected from the shooting condition setting data memory 331 for each scene. Shooting conditions are set based on the shooting program) (step S103). For example, when “person” is selected as the shooting mode, EV shift (exposure correction): ± 0, strobe: auto, white balance: auto, ISO sensitivity: auto, etc. are set. . In setting the shooting conditions, information for identifying the photographer, such as user A, user B, and user C, is also set according to the operation on the operation unit 23.

  Next, photometric processing and AF processing are executed (step S104), and a through image of the subject image is displayed on the display unit 14 (step S105). Therefore, the user adjusts the direction of the digital camera 1 while viewing the through image displayed on the display unit 14. Further, it is determined whether or not the release button 3 has been half-pressed (step S106). If the release button 3 has not been half-pressed, other key processing is executed (step S107).

  When the release button 3 is half-pressed by the user, the determination in step S106 is YES, and the process proceeds from step S106 to step S108 to detect the vertical direction and horizontal direction of the digital camera 1 detected by the two acceleration sensors 51 and 52. Are detected and sequentially recorded in the data memory 33 (step S108). Further, photometric processing and AF processing are executed (step S109).

  Next, the previous blur amount evaluation value corresponding to the shooting condition is read (step S110). That is, assuming that “person” is selected as the shooting scene or subject in step S103, the shooting conditions in the shooting condition setting data memory 331 corresponding thereto are set, and the user A is set, the user's camera shake is set. The blur evaluation value of user A (blur amount data for each user) is read from the result data memory 332.

  In this embodiment, the shake amount data for each user is recorded in the camera shake result data memory 332. However, the feature amount of the shake for each user may be recorded. In this case, the feature amount of camera shake is read out as a shake amount evaluation value.

  Then, it is determined whether or not the blur evaluation value of the shooting condition for the user read in step S110 is equal to or greater than a predetermined value (step S111). If this determination is NO and the blur evaluation value of the shooting condition for the user is less than a predetermined value, it is estimated that the camera shake in the shooting condition of the user is small and no camera shake correction is necessary. The Therefore, in this case, the camera shake correction function is set to OFF.

  Thereby, when the user performs shooting under shooting conditions with less camera shake, it is possible to prevent an unnecessary camera shake correction function from operating.

  Further, as a result of the determination in step S111, when the blur amount evaluation value of the photographing condition is equal to or greater than a predetermined value, the camera shake correction function is set to ON, and the rotary mirror 18 and the electric mirror Y direction driving unit are set. The camera shake correction device including 59 and the electric mirror X direction driving unit 60 is activated (step S113).

  Therefore, it is possible to perform blur correction according to the skill level and the degree of occurrence of camera shake that are different for each user. Therefore, the blur correction function can be appropriately generated according to the user without increasing the processing time and the processing burden due to unnecessary blur correction.

  In step S114 following step S113, it is determined whether or not the release button 3 that has been half-pressed is fully pressed. If not, the process returns to step S106. When the release button 3 that has been half-pressed by the user is fully pressed, the determination in step S114 is YES. Accordingly, the process proceeds from step S114 to step S115, an exposure timer is set according to the photometric value and the exposure condition, and timer timing is started (step S115). Further, the blur amount in the vertical direction and the horizontal direction (Yaw / Pitch direction) of the digital camera 1 detected by the both acceleration sensors 16 and 17 is detected and sequentially recorded in the data memory 33 (step S116).

  Next, it is determined whether or not the camera shake correction function is ON (step S117). When the process of step S112 is executed and the camera shake correction function is OFF, the process proceeds to step S120 without executing the processes of step S118 and step S119. If the camera shake correction function is ON by executing the process of step S113, the shake correction amount in the Yaw / Pitch direction is calculated from the shake amount in the Yaw / Pitch direction detected in step S116. This is calculated and stored in the camera shake correction setting data memory 333 (step S118). Then, in accordance with the shake correction amount calculated and stored in the camera shake correction setting data memory 333, the camera shake correction device in the Yaw / Pitch direction, that is, the electric mirror Y direction driving unit 59 and the electric mirror X direction driving unit 60, Drive to execute the blur correction process (step S119).

  FIGS. 7A to 7C show an operation mode of the mirror 185 at the time of camera shake detection in this embodiment, and FIG. 7A shows a state in which no camera shake occurs. B) shows a state in which camera shake has occurred, and FIG. 10C shows a state in which camera shake correction has been performed. That is, when the camera shake occurs as shown in FIG. 7B from the state of FIG. 7A, and as a result, the optical axis P becomes P ′ shifted by + θ °, the lens group 19, the diaphragm 57 and R guided to the image sensor 20 via the shutter 58 are also shifted to R ′, and blurring occurs by the difference of D. In this case, the processing in step S119 corrects camera shake by rotating the mirror 185 by −θ / 2 ° according to + θ °, as shown in FIG. It can be guided to the image sensor 20.

  Then, the exposure / photographing operation is started according to the photographing condition set in step S103 (step S120), and the shutter 58 is opened by the processing in step S120, and the image sensor 20 is exposed. Next, it is determined whether or not the exposure time counted by the exposure timer has ended, that is, whether or not the remaining time of the exposure timer has become “0” (step S121), and the exposure time ends. If not, the process returns to step S116, and the process from step S116 is repeatedly executed. When the exposure time is over, the exposure / photographing operation is stopped and the shutter 58 is closed, as well as camera shake detection (angular velocity sensors 16, 17, angular velocity detectors 51, 52, integrators 53, 54), camera shake correction device. (Electric mirror Y direction driving unit 59 and electric mirror X direction driving unit 60) are stopped (step S122).

  Further, the captured image is compressed and encoded, and the compressed and encoded captured image is recorded in the external memory medium 39 (step S123), and the captured image is displayed for review (step S124). Further, the blur amount data is totaled for each photographing mode, photographing condition, and user, and the evaluation value is updated (step S125).

  That is, the current shooting is by user A, “person” is selected as the shooting mode, EV shift (exposure correction): ± 0, strobe: auto, white balance: auto, ISO sensitivity: auto as shooting conditions. ... Is set, the evaluation value of the user A recorded in the area 332A shown in FIG. 5 in the user's camera shake data memory 332 is detected in step S116 and sequentially recorded. The blur amount in the pitch direction or an evaluation value based on this blur amount is updated.

  Therefore, the data in the camera shake result data memory 332 of the user is updated every time the user performs shooting, and the determination in step S111 is performed based on the updated data. Thus, based on the latest data of the user, it is possible to control whether the shake correction function is turned ON or OFF when the user performs shooting under the shooting conditions, and the shake correction function is accurately turned ON / OFF. Control can be performed.

  In this embodiment, the evaluation value is updated in step S125. However, the shooting condition setting data in the shooting condition setting data memory 331 for each scene may be updated based on the evaluation value and the blur amount. Good. In other words, by changing the shooting condition setting data in the shooting condition setting data memory 331 according to the camera shake amount detected and recorded in step S116, the shooting condition is such that a camera shake correction effect corresponding to the camera shake amount occurs. Shooting can be performed, and an appropriate camera shake correction effect can be obtained depending on shooting conditions.

  FIG. 8 is a diagram showing a specific configuration example of the angular velocity sensors 16 and 17. In this example, a piezoelectric vibration gyro 81 using a ceramic bimorph vibrator has a support pin (also a lead wire) 81 a and a piezoelectric element 82. The vibration gyro 81 is connected to the HPF 82, the LPF 83, and the like to constitute a circuit. In the vibration gyro 81, the Coriolis force generated by the rotation is converted into a voltage signal by a piezoelectric element by a circuit as shown in each figure (C), and a voltage proportional to the angular velocity can be detected. When used for camera shake detection, when shooting while standing on a stationary ground, there are generally many camera shakes of about 3 to 10 Hz, but when shooting while walking, it is slightly higher, about 10 to 18 Hz. When shooting while riding, blurring of about 20 to 25 Hz also occurs. Therefore, an ultra-compact sensor with a response of 50 Hz and a detection range of about ± 360 deg / sec so as to cope with the occurrence of blurring of about 0.5 to 25 Hz. Is available.

  In addition, in order to remove the temperature drift of the stationary output due to the change in ambient temperature, an HPF (high pass filter) (with a cutoff frequency fc = 0.3 to 0.5 Hz) is connected to the sensor output, and the DC component is An LPF (low-pass filter) that removes high-frequency components above the response frequency (with a cut-off frequency of about fc = 1 kHz to 4 kHz) is connected to remove the vibration noise inside the sensor (around 20 to 25 Hz). To do. Vibration due to camera shake can be detected as an angular velocity signal by a gyro, integrated and calculated by a microcomputer circuit or the like, converted into angular displacement, and a camera shake correction amount can be determined based on the angular velocity and angular displacement.

  FIG. 9 is a diagram illustrating a specific configuration example of a camera shake amount detection circuit. As shown in the figure, a drive unit 103 is connected to a Yaw direction angular velocity sensor (vibration gyro) 101 and a Pitch direction angular velocity sensor (vibration gyro) 102, and a sensor detection circuit unit 104 and a digital signal processing unit 105 are provided. Via the control unit 106. The control unit 106 includes an input / output interface 1061, a CPU 1062, and the like, and is connected to a data memory 109, a program memory 108, and a clock circuit 109. The data memory 109 is provided with a camera shake result data memory 1071 for each user. Yes. The sensor detection unit 104 includes an HPF, a differential amplifier, an LPF, and an A / D converter D provided for each angular velocity sensor 101 and 102, and the digital signal processing unit 105 is configured for each angular velocity sensor 101 and 102. The HPF is provided with a phase compensation circuit and an integration circuit.

  By using such a camera shake amount detection circuit, the vibration waveform of camera shake illustrated in FIG. 10A and the frequency characteristics of camera shake illustrated in FIG. ) And (b-2), the frequency characteristics of camera shake (unexperienced person, during moving shooting) can be recorded in the camera shake result data memory 1071 for each user.

  FIGS. 11A to 11C are diagrams illustrating another example of the configuration of the shake correction device, which is a MEMS rotation mirror type shake correction device using an electromagnetic Lorentz force. As shown in FIG. 11A, an outer turntable 202 and an inner turntable 203 are respectively mounted on a MEMS substrate 201 such as a silicon substrate via a torsion bar (torsion spring) 204. A mirror 205 is mounted on the inner turntable 203. Further, the MEMS base 201 is mounted on the outer turntable 202 as shown in FIG. 11B and FIG. 11C which is a cross-sectional view taken along the line AA ′ in FIG. 11B. A magnet 206 is arranged on each of the four circumferences of the outer turntable 202, a printed circuit board 207 and a yoke 208 are provided, and a connector 210 connected to the printed circuit board 207 is provided.

  Therefore, according to the shake correction apparatus, it is possible to make it thinner than the rotary mirror shown in FIG. 3, and therefore it can be easily mounted on a small digital camera.

(Second Embodiment)
FIG. 12 is a flowchart showing a processing procedure in another embodiment of the present invention. In this embodiment, an allowable blur amount is calculated according to the image size at the time of reproduction output, such as the size of the printing paper on which an image is printed after shooting and the screen size of the display unit 14, and blur reduction shooting is performed based on the calculated amount. It is what you want to do.

The control unit 25 executes processing according to this flowchart based on the program stored in the program memory 32. First, shooting conditions such as the exposure setting time T are set (step S201), and the size of the printing paper is selected according to the operation of the operation unit 23 by the user (step S202). Further, it is determined whether or not “view a printed image from the diagonal distance of the printing paper” is selected by an operation on the operation unit 23 by the user (step S203). If this is selected, the allowable blur δ is set according to the image size Y using the following exemplary formula (step S204).
(Example) Allowable blur δ = (image size Y / paper size Sp) × paper size Sp × tan (3 ′) = Y × tan (3 ′)

When “Appreciate the printed image from the diagonal distance of the printing paper” is not selected and “Appreciate from a certain clear viewing distance” is selected, the printing paper size Sp is set using the following exemplary formula. Accordingly, the allowable blur δ is set (step S205).
(Example) Allowable blur δ = (Y / Sp) × 250 (mm) × tan (3 ′)

Next, photometric processing, zoom processing, and AF processing are executed (step S206), and lens focal length information (f) is read (step S207). Then, using the following exemplary formula, an allowable blur amount is set according to the allowable blur amount δ, the lens focal length f, and the set exposure time T (seconds) (step S208).
(Example) Allowable blurring amount (angle) θB = 2 × tan−1 (δ / 2f)
Allowable blurring amount (angular velocity) ωB = θB / T

  In this way, the allowable blur amount is, for example, allowable blur (permissible circle of confusion) according to the imaging size (diagonal) Y or according to the inspection imaging size Y and the enlargement magnification to the printing paper. δ is obtained, and an angle of view corresponding to the allowable blur δ is determined as an allowable blur angle θ according to the allowable blur δ and the focal length f of the photographing lens.

That is, the shooting angle of view θ is calculated from the focal length f (mm) and the image size (diagonal) Y (mm), and the angle of view θ = 2 × tan−1 (Y / 2f),
Although the appearance and impression are different between blur and blur, if it is considered acceptable with the same size, allowable blur angle (θB) / angle of view (θ) = allowable blur (δ) / image size (Y )
Allowable blur angle θB = 2 × tan−1 (δ / 2f)
Permissible blur angular velocity ωB = allowable blur angle θB / exposure time T = 2 × tan−1 (δ / 2f) / T,
Can be set.

  Then, the blur amount (angle θ, angular velocity ω) of the user stored in advance in the data memory 33 is read and compared with the allowable blur amount (angle θB, angular velocity ωB) (step S209), θ ≧ θB, or It is determined whether or not ω ≧ ωB (step S210). As a result of this determination, if θ ≧ θB or ω ≧ ωB, and the amount of shake of the user is greater than or equal to the allowable shake, it is determined that camera shake correction is necessary, and camera shake correction is turned on (step S112). ). If θ ≧ θB or ω ≧ ωB is not satisfied and the amount of shake of the user is less than the allowable shake, it is determined that camera shake correction is unnecessary, and camera shake correction is turned off (step S211).

  In other words, in the present embodiment, the camera shake correction is turned ON / OFF depending on whether the camera shake amount of the user is greater than or less than the allowable shake amount, thereby preventing camera shake shooting more accurately. Unnecessary camera shake correction function can be prevented from operating.

  (Third embodiment)

  Although omitted in the flowchart shown in FIG. 12, in this embodiment as well, the processing of S114 to S125 is executed and the captured image is compressed and encoded as in the first embodiment described above. It is stored in the external memory medium 39. Therefore, in the first and second embodiments, the photographed image is stored in the external memory medium 39 without being subjected to the blur correction process. In the third embodiment, the photographed image is blurred. The correction processing is performed and then recorded in the external memory medium 39.

  FIG. 13 is a flowchart showing the processing content of the blur correction processing that is performed immediately before recording a photographed image in the memory medium 33 in the present embodiment. First, the outline will be described. The captured image is subjected to Fourier transform and discrete Fourier transform (DFT) (step S601), and a Fourier transform image of a degraded image is generated (step S602). Also, p (u, v) or PSF is estimated by PSF method, zero cross method, Hough transform method, inverse filter method, etc. (step S603), linear blur evaluation value, blur direction angle (θ), blur distance. (L) is calculated (step S604). Further, straight blurring (zero crossing in the θ direction with a period of 1 / L) is calculated by P (u, v) = sin (πfL) / πfL, (f = ucos θ + vsin θ) (step S605), and I (u, v) = G (u, v) / P (u, v) is calculated (step S609), and i (x, y) = Σu = 0M-1Σv = 0n-1I (u, v) W1-uxW2-by (however, , W1 = exp (−j2π / M), W2 = exp (−j2π / N)) (step S610).

  Alternatively, p (u, v) or PSF is similarly estimated by the PSF method, zero-cross method, Hough transform method, inverse filter method, or the like (step S606), the evaluation value of the linear blur, the radius of the focus spread (r) Is calculated (step S607). Further, the defocus (the concentric zero crossing with a cycle of 1.01π / r) is P (u, v) = 2 · J1 (r−R) / r · R, (the first kind Bessel when J1 = 1). Function) (step S608), and the processes of steps S609 and S610 are executed.

  That is, in the present embodiment, after a deteriorated image such as an image with blurring or an image with defocusing is converted into an image signal in the frequency domain by Fourier transform or the like, a PSF (focal point) with blurring or defocusing is generated. Distribution function, point spread function), and based on the estimated PSF function, the estimated PSF function is calculated with an inverse function on the degraded image in the frequency domain, and the obtained frequency domain image is obtained. By returning to the image signal of the spatial domain by inverse Fourier transform or the like, the blurring image or the blurred image is corrected and the image is restored.

In general, in the image restoration by the PSF method, an original image i (x, y) free from blurring and blurring is regarded as a degraded image by degrading the degradation component p (x, y) that causes blurring and blurring.
If g (x, y) = p (x, y) * i (x, y) (* is a convolution operation),
p (x, y) is obtained as PSF (Point Spread Function), LSF (Line Spread Function), etc. If p (x, y) can be estimated well, the original image i (x, y) can be restored by deconvolution (deconvolution integration).

That is, when a deteriorated image g (x, y) such as a photographed image is converted into a frequency axis by Fourier transform or the like, and G [u, v] is obtained,
Since G [u, v] = P [u, v] · I [u, v] (convolution is multiplication of Fourier transforms on the frequency axis), the degradation component P [u, v ] In the frequency domain and if P [u, v] can be estimated, 1 / P [u, v] is calculated and obtained as an inverse filter, and G [u, v] is multiplied as follows. In addition, the original image i (x, y) can be restored by calculation.
I [u, v] = G [u, v] / P [u, v] (division between Fourier transforms)
i (x, y) = inverse Fourier transform {I [u, v]}
= Σu = 0M−1Σv = 0n−1 · I (u, v) W1uxW2vy (W1 = exp (−j2π / M), W2 = exp (−j2π / N)),

Incidentally, the Fourier transform F [u, v] of the image (x, y) is the discrete Fourier transform (DFT).
F [u, v] = (1 / MN) Σx = 0M−1Σv = 0N−1f (x, y) W1uxW2vy
(W1 = exp (−j2π / M), W2 = exp (−j2π / N))

In the discrete cosine transform (DCT),
F [u, v] = (4√MN) C (u) C (v) ・ ΣxΣvf (x, y) · cos {(2x + 1) uπ / 2M} cos {(2y + 1) uπ / 2N}
However, C (u), C (v) = 1√2 (u, v = 0), C (u), C (v) = 1 (u, v ≠ 0)
However, various high-speed calculation algorithms such as butterfly type computation for fast Fourier transform (FFT) have been developed, and these may be used.

  In the following, the estimation method of PSF and P [u, v] in this PSF method is used for estimation of linear blur amount and estimation of focus and defocus amount. Based on this, an example of restoring a “straight line blur” image and a “focus blur” image will be described. In general, the amplitude distribution of G [u, v] obtained by Fourier transforming an image f (x, y) without blurring or blurring becomes a straight blurring pattern as shown in (b) in step S602, and is near the center. Depending on the blur angle, several high-frequency components appear in the form of several elongated slanted ellipses that are distorted or distorted.

  Further, G [u, v] obtained by Fourier transform of the defocused degraded image g (x, y) becomes a defocused pattern as shown in (d), and the high-frequency component in the center part is missing or distorted in a concentric manner. It becomes a pattern. Similarly, when both straight blurring and out-of-focus blur occur, a pattern having both features is obtained as shown in FIG.

(Estimation of blur direction and blur distance by PSF method)
FIG. 14 shows an estimation method of the blur direction (θ), blur distance (L), and spread radius (r) of the focal blur in the conventional PSF method. The blur direction (θ) is G [u, v]. The blur distance (L) or the focal spread radius (r) is obtained by sequentially calculating the restored images iL and iL + 1 and calculated from the correlation value C (L). The calculation is repeated until the correlation value C (L) is saturated to a degree of correlation equal to or greater than a predetermined value. However, since this method takes time to calculate, there is also a method of obtaining in the following multi-gradation Hough conversion.

FIG. 15 is a diagram illustrating a method of estimating the blur direction (θ), the blur distance (L), or the spread radius (r) of the focal blur by PSF method and multi-gradation Hough conversion. A circle in the center of the free spectrum of the degraded image G [u, v] such as straight line blurring is expressed in the θ-ρ space by the Hough conversion method (used widely for estimation and detection of straight lines passing through a plurality of points). And a Hθ (ρ) waveform cut out for each angle θ of the H (θ, ρ) value.
The entropy E (θ) = ΣρPlog2 (1 / P) (0 ° ≦ θ <180 °) is obtained,
The angle θ at which E (θ) is minimized can be estimated as the linear blur direction (θ).
(However, P = (θ, ρ) / HSUM (θ), HSUM (θ) is the sum of the in-circle pixel values, and is HSUM (θ = Σ (−R ≦ 0 ≦ R) H (θ, ρ)). .)
Further, when the period (T1) of the minimum point of the Hθ (ρ) waveform in the blur direction (θ) is obtained, the blur distance (L) = 1 / TL is obtained.

Further, a C (ρ) waveform obtained by averaging H (θ, ρ) from 0 ° to 179 ° in the θ-axis direction,
C (ρ) = ΣρHθ (ρ) / 180 (0 ° ≦ θ <180 °)
From the period (Tr) of the minimum point of the C (θ) waveform, the radius (r) of the focal blur spread is
Radius (r) = 1.01 × π × Tr
MN) C (u) C (v) .ΣxΣvf (x, y) .cos {(2x + 1) uπ / 2M} cos {(2y + 1) uπ / 2N}

(Hough conversion)
By the way, in Hough conversion (also called Hough conversion or Hugh conversion), a point on a two-dimensional coordinate xy plane is generally a curve on a θ-ρ bright surface by a conversion formula of (ρ = x / cos θ + y · sin θ). In addition, a straight line on the xy plane can be converted and inversely converted to a point on the θ-ρ bright surface, respectively. For example, when it is desired to obtain a straight line L passing through points A, B, and C on the xy plane, curves A ′, B ′, and C ′ on the θ-ρ plane obtained by converting the points A, B, and C are used. When the intersection point P (θ, ρ) intersecting is obtained, the point P (θ1, ρ1) is inversely transformed on the xy plane, the length of the perpendicular line dropped from the zero point is ρL, and the angle of the perpendicular line Is a straight line to be obtained.

  The Hough conversion is widely used in the field of image processing, such as extracting a straight line region from a two-dimensional image in this way, so the details are omitted, but in the above multi-gradation Hough conversion, this Hough conversion The brightness (brightness or density having gradation) of the array H (θ, ρ) is defined as a multi-gradation two-dimensional image with H (θ, ρ) = f (x, y), as described above. When calculating the intersection of a plurality of curves, brightness (gradation value) is added, and the point at which the gradation value becomes the maximum can be used as an intersection to quickly determine by approximation calculation.

  As described above, the direction (angle θ) of the linear blur image is obtained from G [u, v] obtained by Fourier transforming the degraded image g (x, y) on the frequency axis by the zero cross method or multi-gradation Hough conversion. ) And the straight blurring distance (number of pixels L), or the focal spread radius (number of pixels r) of the defocused image is estimated by the above-described calculation, and based on these, the blurring is corrected by image processing. Or restore an image with less blur.

  Note that the blur information recorded in the data memory 33 is not limited to the amount of camera shake and the actual image blur data, but the frequency, direction, vibration waveform, waveform characteristics, frequency component, Fourier transform coefficient, etc. of the blur are detected. It is also possible to record camera shake feature data or image blur frequency, image motion vector, resolution, contrast, histogram, frequency characteristics of the image, Fourier transform, DCT transform, etc. Good.

  Also, record the shooting conditions (shooting brightness, exposure time, focal length, shooting distance, strobe conditions) when the amount of camera shake or image blur exceeds a predetermined threshold, and the cumulative score. It may be simplified or the amount of recorded data may be compressed.

  Alternatively, based on the recorded data of the camera shake amount and image shake amount of the individual user, the camera shake amount and image shake under the predetermined shooting conditions of the time are determined from the secular change, proficiency level, and data for each shooting condition. An amount or the like may be predicted and calculated, and the correction mode and the correction parameter may be automatically set according to the predicted camera shake amount and image blur amount.

  As shown in FIG. 4, the digital camera 1 includes a communication control block 36 and a transmission / reception unit 41 such as a wireless LAN. Therefore, when the digital camera 1 is connected to a manufacturer's server via a network using these, camera shake or image blur performance data (or image feature data, shooting condition data, (Score data) is automatically transmitted to the server, and the server records and records the above-mentioned camera shake performance data in a database for each individual or for each shooting condition, and manages and analyzes the blur characteristics for each individual user or for each shooting condition. The camera control program and correction parameters may be updated and written on the basis of aggregate analysis data from a large number of users.

  In the embodiment, the present invention is applied to the digital camera 1 having the external structure shown in FIG. 1. However, the present invention is not limited to this, and is not limited to this. A camera, a main body and a lid, one side with an LCD finder and the other with a monitor, a two-fold digital camera, a digital camera that can take a picture of the user by user operation, two screens with two adjacent screens The present invention can be applied to various devices such as an imaging device having another structure, such as a digital camera that displays a single continuous image, or a mobile phone having an imaging function.

(A) is a front view of a digital camera common to each embodiment of the present invention, and (B) is a rear view. 2 is a side perspective view of the digital camera. FIG. (A) is a front view of the rotary mirror 18, and (B) is a side view. It is a block diagram which shows the circuit structure of the digital camera. It is a conceptual diagram which shows the imaging condition setting data memory for every scene, and the camera shake result data memory of a user. It is a flowchart which shows the process sequence in 1st Embodiment. (A) is a state without camera shake, (B) is a state where camera shake has occurred, and (C) is a diagram showing a state where camera shake is corrected. It is a figure which shows the piezoelectric vibration gyro using a ceramic bimorph vibrator. It is a figure which shows the specific structural example of the detection circuit of camera shake amount. It is a figure which shows the example of a waveform recorded. It is a figure which shows the other structural example of a blurring correction apparatus. It is a flowchart which shows the process sequence in 2nd Embodiment of this invention. It is a flowchart which shows the processing content of the blurring correction process in 3rd Embodiment. It is a figure which shows the example of the estimation method of a blur amount and a blur amount. Blur direction, blur distance, or focus by PSF method and multi-gradation Hough conversion

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Digital camera 2 Main body 3 Release button 14 Display part 16 1st acceleration sensor 17 2nd angular velocity sensor 18 Rotating mirror 19 Lens group 20 Imaging element 23 Operation part 24 Input circuit 25 Control part 26 Display memory 27 Display drive block 28 Image buffer Memory 29 Image signal processing unit 30 Compression encoding / decompression decoding unit 31 Still image / moving image memory 32 Program memory 33 Data memory 38 Shooting control unit 39 External memory medium 51 Angular velocity detection unit 65 Video signal processing unit 331 Shooting condition setting data Memory 332 Camera shake result data memory

Claims (9)

Photographing means;
A blur correction unit that corrects blur of an image captured by the shooting unit;
Blur detection means for detecting camera shake,
Blur information storage means for storing blur information indicating blur of the camera body detected by the blur detection means in correspondence with shooting conditions set in the camera;
An acquisition unit configured to acquire corresponding blur information from the blur information storage unit in accordance with a shooting condition set in the camera;
A camera comprising: control means for controlling the operation of the shake correction means based on the shake information acquired by the acquisition means. The control means includes
Based on the blur information acquired by the acquisition unit, a correction determination unit that determines whether or not to correct blur of an image captured by the imaging unit,
2. The camera according to claim 1, wherein the blur correction unit is operated or stopped according to a determination result of the correction determination unit. The control means includes
A blur amount determining unit that determines whether or not a blur amount indicated by the blur information acquired by the acquiring unit is greater than or equal to an allowable blur amount;
2. The camera according to claim 1, wherein the blur correction unit is operated or stopped according to a determination result of the blur amount determination unit.   The camera according to claim 1, wherein the blur correction unit is a blur correction mechanism that drives an optical system included in the photographing unit.   The camera according to claim 1, wherein the blur correction unit is an image correction unit that corrects an image captured by the photographing unit.   6. The blur information storage unit updates the blur information based on a blur of the camera body detected by the blur detection unit each time shooting is performed by the shooting unit. Any one described in the camera. The camera according to claim 1, wherein the blur information storage unit stores the blur information together with information indicating a user of the camera. A computer having a camera comprising: an imaging unit; a blur correction unit that corrects blur of an image captured by the imaging unit; and a blur detection unit that detects blur of the camera body;
Blur information storage means for storing blur information indicating blur of the camera body detected by the blur detection means in correspondence with shooting conditions set in the camera;
An acquisition unit that acquires corresponding blur information from the blur information storage unit according to the shooting conditions set in the camera;
A camera control program that functions as a control unit that controls the operation of the blur correction unit based on the blur information acquired by the acquisition unit. A camera control method comprising: an imaging unit; a blur correction unit that corrects blur of an image captured by the imaging unit; and a blur detection unit that detects blur of the camera body,
A blur information storage step for storing blur information indicating blur of the camera body detected by the blur detection unit in a storage unit in association with shooting conditions set in the camera;
An acquisition step of acquiring corresponding blur information from the storage unit according to the shooting conditions set in the camera;
And a control step for controlling the operation of the shake correcting means based on the shake information acquired by the acquiring means step.

Images