JP2015105975A - Image shake correction device, control method thereof, program and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make operability of panning or the like compatible with an image shake correction performance.SOLUTION: An image shake correction device 100 includes: a low frequency component attenuation part 102 for attenuating a low frequency component of output from a shake detection part 101; a frequency separation part 103 for separating output of the low frequency component attenuation part 102 into a low frequency signal and a high frequency signal; first calculation parts 104 and 105 each for calculating a first shake correction amount on the basis of the high frequency signal; second calculation parts 108 and 109 each for calculating a second shake correction amount on the basis of the low frequency signal; a first image shake correction part 107 for correcting image shake on the basis of the first shake correction amount; a second image shake correction part 111 for correcting image shake on the basis of the second shake correction amount; and a panning control part 112 in which, if output calculated on the basis of a high frequency angular velocity signal is equal to or greater than a predetermined value, a separation frequency of the frequency separation part 103 is made higher and if output calculated on the basis of a low frequency angular velocity signal is equal to or greater than a predetermined value, an attenuation start frequency of the low frequency component attenuation part 102 is made higher.

Description

  The present invention relates to a technique for correcting shake of a captured image using a plurality of image shake correction means.

  In recent years, with the downsizing of imaging devices and the increase in the magnification of optical systems, attention has been paid to the fact that shakes in the imaging devices are a major cause of degrading the quality of captured images. Various image blur correction functions have been proposed for correcting shake of captured images. As a conventional image blur correction function mounted on an imaging apparatus, there is a method of controlling by using a plurality of image blur correction units together (for example, see Patent Document 1).

  Japanese Patent Application Laid-Open No. 2004-228561 discloses a method of separating angular velocity sensor signals into a low frequency band and a high frequency band and correcting shake of a captured image by different image shake correction units.

Japanese Patent No. 451897

  However, although the concept of separating the angular velocity sensor signal into the low frequency band and the high frequency band is disclosed in the above-described conventional example, the correction amount saturation countermeasure at the time of panning is not disclosed. In the image blur correction technique, it is important to correct a shake that is not intended by the photographer and not to correct a motion of an image caused by a camera work such as panning performed intentionally.

  The present invention has been made in view of the above-described problems, and an object thereof is to improve operability of camera work such as panning and image blur correction performance when correcting image blur using a plurality of image blur correction units. It is to realize coexistence.

  An image shake correction apparatus according to the present invention includes a shake detection unit that detects a shake of an imaging apparatus, a low frequency component attenuation unit that attenuates a low frequency component of an output of the shake detection unit, and an output of the low frequency component attenuation unit. Separating means for separating the signal into a low frequency signal and a high frequency signal, a first calculation means for calculating a first shake correction amount based on the high frequency signal, and a second shake correction amount based on the low frequency signal. Second calculation means for calculating, first image shake correction means for correcting shake of the photographed image based on the first shake correction amount, and photographed image based on the second shake correction amount. A second image blur correction unit that corrects a shake, and a control unit that determines a motion of the imaging apparatus based on an output calculated based on the high-frequency signal or the low-frequency signal and changes the control. , The control means is the high-frequency signal When the output calculated based on the low frequency signal is higher than a predetermined value, the separation frequency of the separation means is increased. When the output calculated based on the low frequency signal is higher than the predetermined value, the low frequency component attenuation means The attenuation start frequency is increased.

  According to the present invention, it is possible to realize both camera work operability such as panning and image blur correction performance when correcting image blur using a plurality of image blur correction units.

1 is a block diagram showing a configuration of an image shake correction apparatus according to a first embodiment of the present invention. FIG. 3 is a block diagram illustrating an example of first and second image shake correction units. The flowchart for demonstrating the process which a panning control part performs in 1st Embodiment. The figure which shows an example of the filter characteristic of a low frequency component attenuation | damping part and a frequency separation part. The flowchart for demonstrating the process which a panning control part performs in 2nd Embodiment. FIG. 9 is a block diagram illustrating a configuration of an image shake correction apparatus according to a third embodiment. The flowchart for demonstrating the process which a panning control part performs in 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, image blur correction control in either the horizontal direction or the vertical direction of the image will be described, and the image blur correction control in the other direction is the same control, and thus description thereof will be omitted.

(First embodiment)
FIG. 1A is a block diagram showing a configuration of an image blur correction apparatus according to the first embodiment of the present invention. Each component of the image blur correction apparatus 100 in FIG. 1A and the operation of an example thereof will be specifically described. The image shake correction apparatus 100 is mounted on an imaging apparatus such as a digital camera or a video camera that captures a subject image.

  The angular velocity sensor 101 detects a shake applied to the image blur correction apparatus 100 as an angular velocity signal, and supplies the angular velocity signal to the low frequency component attenuation unit 102. The low frequency component attenuating unit 102 has a function of changing its characteristics in an arbitrary frequency band, and attenuates the low frequency component included in the angular velocity data from the angular velocity sensor 101 to output a signal in the high frequency band. To do. FIGS. 1B and 1C show examples of the configuration of the low frequency component attenuating unit 102. The low-frequency component attenuating unit 102 may be configured by only the HPF 201 (high-pass filter) as shown in FIG. 1B, or the LPF 202 (low-pass filter) from the input signal as shown in FIG. 1C. The output may be subtracted by the subtracter 203. The change in the characteristics of the low-frequency component attenuation unit 102 can be realized by making the cut-off frequency of the HPF 201 or LPF 202 variable.

  The frequency separation unit 103 further separates the output of the low frequency component attenuation unit 102 into a high frequency angular velocity signal (high frequency signal) and a low frequency angular velocity signal (low frequency signal), and supplies them to the sensitivity calculation units 104 and 108, respectively. . FIGS. 1D and 1E show examples of the configuration of the frequency separation unit 103. FIG. For example, in the example shown in FIG. 1D, the output after passing the input signal through the HPF 204 is a high-frequency angular velocity signal, and the output obtained by subtracting the output of the HPF 204 from the input signal by the subtractor 205 is the low-frequency angular velocity signal. . Further, in the example shown in FIG. 1E, the output after passing the input signal through the LPF 206 is a low frequency angular velocity signal, and the output obtained by subtracting the output of the LPF 206 from the input signal by the subtractor 207 is the high frequency angular velocity signal. . Further, the frequency separation unit 103 can change the separation frequency band by changing the cutoff frequency of the HPF 204 or the LPF 206.

  Each block of the sensitivity calculation unit 104, the integrator 105, and the limiter 106 is a block that calculates the image blur correction amount of the first image blur correction unit 107 based on the high-frequency angular velocity signal from the frequency separation unit 103. The sensitivity calculation unit 104 multiplies the high-frequency angular velocity signal by a coefficient indicating how much the first image shake correction unit 107 should be driven, that is, sensitivity, to correct the shake detected by the angular velocity sensor 101. Is supplied to the integrator 105. The integrator 105 has a function capable of changing the characteristics in an arbitrary frequency band, integrates the output from the sensitivity calculation unit 104, and calculates the correction amount of the first image shake correction unit 107. The limiter 106 limits the output of the integrator 105 so that the first image blur correction unit 107 is driven inside the correctable range.

  Each block of the sensitivity calculation unit 108, the integrator 109, and the limiter 110 is a block that calculates the image blur correction amount of the second image blur correction unit 111 based on the low frequency angular velocity signal from the frequency separation unit 103. The sensitivity calculation unit 108 multiplies the low-frequency angular velocity signal by a coefficient indicating how much the second image shake correction unit 111 should be driven, that is, sensitivity, to correct the shake detected by the angular velocity sensor 101. The result is supplied to integrator 109. The integrator 109 has a function capable of changing the characteristics in an arbitrary frequency band, integrates the output from the sensitivity calculation unit 108, and calculates the correction amount of the second image blur correction unit 111. The limiter 110 limits the output of the integrator 109 so that the second image blur correction unit 111 is driven inside the correctable range.

  The first image blur correction unit 107 and the second image blur correction unit 111 may be configured as shown in FIGS. 2A to 2C, for example. FIG. 2A illustrates a shake caused by an operation such as shifting the correction optical system 305 in the imaging optical system in the imaging apparatus in a direction perpendicular to the optical axis or rotating about an arbitrary point on the optical axis. An example of an image blur correction unit to be corrected is shown.

  The subtractor 301 subtracts the output of the position detection unit 306 that detects the position of the correction optical system 305 from the input signal, and supplies the deviation data as a result to the control filter 302. The control filter 302 includes an amplifier that amplifies input data with a predetermined gain, and a phase compensation filter. The deviation data supplied from the subtractor 301 is supplied to the control filter 302, subjected to signal processing by the amplifier and the phase compensation filter, and then output to the motor driving unit 303. The motor 304 is a voice coil type motor for driving the correction optical system 305, and the correction optical system 305 is moved by being driven from the motor drive unit 303. The position detection unit 306 includes a magnet and a hall sensor provided at a position facing the magnet, detects the amount of movement of the correction optical system 305, and supplies the detection result to the subtractor 301 described above. Thus, a feedback control system is configured to follow the amount of movement of the correction optical system 305 with respect to the input signal. The correction optical system 305 is a correction system capable of optically correcting image blur by deflecting the direction of the optical axis in accordance with the amount of movement. The correction optical system 305 is driven according to the output of the limiter 106 or the limiter 110 to correct the shake. can do.

  FIG. 2B illustrates an example of an image shake correction unit that corrects shake by shifting the image sensor 310 in the imaging apparatus in a direction perpendicular to the optical axis. In FIG. 2B, compared to FIG. 2A, the object to be driven to correct the shake is only changed from the correction optical system 305 to the image sensor 310, and thus description thereof is omitted.

  FIG. 2C illustrates an example of an image shake correction unit that electronically corrects shake in the imaging apparatus. In FIG. 2C, an image memory 321, a signal processing unit 322, an image sensor 323, and a recording medium / display device 324 are provided in an image pickup apparatus on which the image shake correction apparatus 100 is mounted. The imaging element 323 converts the subject image formed by the imaging optical system of the imaging apparatus into an electrical signal as a captured image signal, and supplies the electrical signal to the signal processing unit 322. The signal processing unit 322 generates a video signal (video signal) based on, for example, the NTSC format from the signal obtained by the image sensor 323 and supplies the video signal to the image memory 321. The memory readout control unit 320 changes the readout position of the image from the image memory 321 in accordance with the output of the limiter 106 or the limiter 110, thereby outputting a video signal whose electronic shake is corrected from the image memory 321.

  Further, the memory read control unit 320 can output a video signal to the recording medium / display device 324 to display an image on the display device or record the image on the recording medium. The recording medium is a magnetic recording medium such as a hard disk or an information recording medium such as a semiconductor memory, and the display device is a device such as a liquid crystal display element (LCD) that displays an image.

  It should be noted that whether the assignment of the first image shake correction unit 107 and the second image shake correction unit 111 is any of FIGS. 2A to 2C can be arbitrarily changed. For example, as disclosed in the prior art document, the first image blur correction unit 107 has the configuration shown in FIG. 2A and the second image blur correction unit 111 has the configuration shown in FIG. Alternatively, the second image blur correction unit 111 may be configured as shown in FIG. If there are two types of correction optical systems, both the first image blur correction unit 107 and the second image blur correction unit may be configured as shown in FIG.

  Returning to FIG. 1A, the panning control unit 112 performs panning determination based on the high-frequency angular velocity signal and the low-frequency angular velocity signal, which are outputs of the frequency separation unit, or the outputs of the integrator 105 and the integrator 109. The characteristics of the frequency separation unit 103 and the low frequency component attenuation unit 102 are changed.

  An example of a processing method executed by the panning control unit 112 will be described in detail below with reference to the drawings. FIG. 3 is a flowchart showing a processing flow of the panning control unit 112. The process of the flowchart in FIG. 3 is repeatedly performed at intervals of, for example, 1/60 second.

  In S100, the panning control unit 112 determines whether the output of the integrator 105 is equal to or greater than a predetermined value. If it is determined in S100 that the output of the integrator 105 is smaller than the predetermined value, the process proceeds to S101. In S101, the panning control unit 112 determines whether the high-frequency angular velocity signal from the frequency separation unit 103 is equal to or greater than a predetermined value. If it is determined in S101 that the high-frequency angular velocity signal is smaller than a predetermined value, the process proceeds to S102. If it is determined in S100 that the output of the integrator 105 is greater than or equal to a predetermined value, or if it is determined in S101 that the high-frequency angular velocity signal is greater than or equal to a predetermined value, panning has been performed or a large shake has occurred. It is determined that it has occurred, and the process proceeds to S103.

  In S103, the separation frequency of the frequency separation unit 103 is set higher than the reference separation frequency (the separation frequency that is initially set), and the frequency band of the shake that is corrected by the first image shake correction unit 107 is shifted to the high frequency side. In S102, it is determined that the shake is small or the panning is finished. If the separation frequency of the frequency separation unit 103 is high in S103, a process of returning the separation frequency to the reference separation frequency is performed. After S102 or S103, the process proceeds to S104.

  In S104, the panning control unit 112 determines whether the output of the integrator 109 is equal to or greater than a predetermined value. If it is determined in S104 that the output of the integrator 109 is smaller than the predetermined value, the process proceeds to S105. In S105, the panning control unit 112 determines whether or not the low frequency angular velocity signal from the frequency separation unit 103 is equal to or greater than a predetermined value. If it is determined in S105 that the low frequency angular velocity signal is smaller than the predetermined value, the process proceeds to S106. If it is determined in S104 that the output of the integrator 105 is greater than or equal to a predetermined value, or if it is determined in S105 that the low frequency angular velocity signal is greater than or equal to a predetermined value, panning has been performed or a large fluctuation has occurred. Is determined, and the process proceeds to S107.

  In S107, the cut-off frequency (attenuation start frequency) of the low-frequency component attenuating unit 102 is set higher than the reference cut-off frequency (the cut-off frequency set first), and the frequency band of the angular velocity signal input to the frequency separating unit 103 is set. Shift to high frequency side. In S106, it is determined that the shake is small or panning is completed. If the cutoff frequency of the low frequency component attenuation unit 102 is high in S107, the process of returning the cutoff frequency to the reference cutoff frequency is performed. Do. After S106 or S107, this process ends.

  Next, the process of the flowchart of FIG. 3 will be described in more detail. The first image blur correction unit 107 and the second image blur correction unit 111 each have a correctable range defined by a limiter 106 and a limiter 110. Therefore, it is necessary to control each of the first image blur correction unit 107 and the second image blur correction unit 111 so as not to reach the correction limit.

  In the flowchart of FIG. 3, the processes of S100 to S103 are processes for controlling the first image blur correction unit 107 so as not to reach the correctable limit. When the output of the integrator 105 becomes large in S100, or when the high-frequency angular velocity signal becomes large in S101, the risk that the first image shake correction unit 107 reaches the correctable limit increases. Since the amplitude of human shake becomes smaller as the frequency becomes higher, the input to the integrator 105 is limited by increasing the separation frequency of the frequency separation unit 103 and shifting the frequency band of the high-frequency angular velocity signal to a high frequency in S103. Can do. As a result, it is possible to prevent the first image blur correction unit 107 from reaching the correctable limit.

  Specifically, the process of S103 is performed by the following control. The graph of FIG. 4B is a graph showing the frequency versus gain characteristics of the HPF 204 when the frequency separation unit 103 has the configuration shown in FIG. In FIG. 4B, the solid line indicates the characteristic when the process of S102 is performed, and the dotted line indicates the characteristic when the process of S103 is performed. In S103, by changing the cutoff frequency of the HPF 204 from f11 (reference separation frequency) to f12 (> f11), the frequency band of the high-frequency angular velocity signal that is the output of the HPF 204 can be shifted to the high-frequency side.

  Also, the graph of FIG. 4D is a graph showing the frequency vs. gain characteristics of the LPF 206 when the frequency separation unit 103 has the configuration shown in FIG. In FIG. 4D, the solid line is the characteristic when the process of S102 is performed, and the dotted line is the characteristic when the process of S103 is performed. In S103, by changing the cutoff frequency of the LPF 206 from f21 (reference separation frequency) to f22 (> f21), the frequency band of the low frequency angular velocity signal that is the output of the LPF 206 can be shifted to the high frequency side. Since the high frequency angular velocity signal is the difference between the input signal and the low frequency angular velocity signal, shifting the frequency band of the low frequency angular velocity signal to the high frequency side means that the frequency band of the high frequency angular velocity signal is shifted to the high frequency side. Be the same.

  In the flowchart of FIG. 3, the processes of S104 to S107 are processes for controlling the second image blur correction unit 111 so as not to reach the correctable limit. When the output of the integrator 109 increases in S104, or when the low-frequency angular velocity signal increases in S105, the risk that the second image blur correction unit 111 reaches the correctable limit increases. At this time, it is possible to limit the input to the integrator 109 by shifting the separation frequency of the frequency separation unit 103 to a lower side and further attenuating the low frequency angular velocity signal. However, this method has the following problems. Occurs. That is, the amount of attenuation of the low-frequency angular velocity signal is turned to the high-frequency angular velocity signal side, and the risk that the first image blur correction unit 107 reaches the correctable limit increases. In order to avoid this, in the present embodiment, the low-frequency component attenuating unit 102 is disposed in front of the frequency separating unit 103. In S107, the cutoff frequency of the low frequency component attenuating unit 102 is increased, and the frequency band input to the frequency separating unit 103 is shifted to the high frequency side to attenuate the low frequency component of the low frequency angular velocity signal. The input to 109 can be restricted. Accordingly, it is possible to prevent the second image shake correcting unit 111 from reaching the correctable limit without affecting the first image shake correcting unit 107.

  Specifically, the process of S107 performs the following control. The graph of FIG. 4A is a graph showing the frequency versus gain characteristic of the HPF 201 when the low frequency component attenuating unit 102 has the configuration shown in FIG. For comparison with the frequency separation unit 103, it is assumed that the frequency separation unit 103 has the configuration illustrated in FIG. 1D and the characteristics illustrated in FIG. 4B described above. In FIG. 4A, the solid line indicates the characteristic when the process of S106 is performed, and the dotted line indicates the characteristic when the process of S107 is performed. In S107, the output frequency band of the HPF 201 can be shifted to the high frequency side by changing the cutoff frequency of the HPF 201 from f10 (reference cutoff frequency) to f11 (> f10). The frequency separation unit 103 frequency-separates the signal that has passed through the low frequency component attenuation unit 102. Therefore, as shown in FIGS. 4A and 4B, the separation frequency of the frequency separation unit 103, that is, the cutoff frequency of the HPF 204 is preferably relatively higher than the cutoff frequency of the low frequency component attenuation unit 102. .

  Further, the graph of FIG. 4C is a graph showing the frequency vs. gain characteristics of the LPF 202 when the low frequency component attenuating unit 102 has the configuration shown in FIG. For comparison with the frequency separation unit 103, it is assumed that the frequency separation unit 103 has the configuration illustrated in FIG. 1E and the characteristics illustrated in FIG. 4D described above. In FIG. 4C, the solid line indicates the characteristic when the process of S106 is performed, and the dotted line indicates the characteristic when the process of S107 is performed. In S107, by changing the cutoff frequency of the LPF 202 from f20 (reference cutoff frequency) to f21 (> f20), the frequency band of the output of the LPF 202 can be shifted to the high frequency side. Since the output of the low frequency component attenuator 102 is the difference between the input signal and the LPF 202, shifting the frequency band of the output of the LPF 202 to the high frequency side means that the frequency band of the output of the low frequency component attenuator is on the high frequency side. It becomes the same as shifting to.

  As described with reference to FIGS. 4A and 4B, the frequency separation unit 103 frequency-separates the signal that has passed through the low-frequency component attenuation unit 102. Therefore, as shown in FIGS. 4C and 4D, the separation frequency of the frequency separation unit 103, that is, the cutoff frequency of the LPF 206 is preferably relatively higher than the cutoff frequency of the low frequency component attenuation unit 102. .

  As described above, in the first embodiment of the present invention, the low frequency component attenuating unit 102 is arranged in the previous stage of the frequency separating unit 103. Then, when there is a risk that the first image blur correction unit reaches the correctable limit, the separation frequency of the frequency separation unit 103 is increased, and when there is a risk that the second image blur correction unit reaches the correctable limit, the frequency is low. The cutoff frequency of the frequency component attenuator 102 is increased. As a result, even when a large shake such as panning occurs, the two image shake correction units appropriately prevent each from reaching the correctable limit, and immediately after the large shake such as panning converges, It is possible to perform optimal image blur correction control that returns to image blur correction.

(Second Embodiment)
Next, an example of the operation of the image shake correction apparatus according to the second embodiment of the present invention will be described. In the present embodiment, the configuration of the image blur correction apparatus is the same as that of the block diagram of FIG. Further, the difference from the first embodiment is that an integrator 105 and an integrator 109 are added as control targets of the panning control unit 112 as indicated by a dotted arrow in the block diagram of FIG.

  FIG. 5 is a flowchart showing a flow of processing executed by the panning control unit 112 in the second embodiment of the present invention. The flowchart of FIG. 5 is obtained by adding the processes of S200 to S203 to the flowchart of FIG. 3, and the processes common to those in FIG.

  In S100, when it is determined that the output of the integrator 105 is equal to or greater than the predetermined value, the process proceeds to S201, and when it is determined that the output is smaller than the predetermined value, the process proceeds to S200. In S201, after the process of making the time constant of the integrator 105 shorter than the reference time constant (the time constant that is set first), the process proceeds to S103. In S200, when the process of shortening the time constant of the integrator 105 is performed in S201, the process of returning to the reference time constant is performed, and then the process proceeds to S101.

  If it is determined in S104 that the output of the integrator 109 is equal to or greater than the predetermined value, the process proceeds to S203, and if it is determined that the output is smaller than the predetermined value, the process proceeds to S202. In S203, the process of making the time constant of the integrator 109 shorter than the reference time constant is performed, and then the process proceeds to S107. In S202, when the process of shortening the time constant of the integrator 109 is performed in S203, the process of returning to the reference time constant is performed, and then the process proceeds to S105.

  As described above, the processes in S103 and S107 are processes for limiting the inputs to the integrator 105 and the integrator 109. However, when the time constants of the integrator 105 and the integrator 109 are long, it takes a long time for the increased output to converge to near zero, and the image blur correction unit may reach the correction limit during that time. Get higher. Therefore, in the process of S201, when the output of the integrator 105 is equal to or greater than a predetermined value, control is performed so that the output of the integrator 105 is quickly converged to near zero. Similarly, in the process of S203, when the output of the integrator 109 is greater than or equal to a predetermined value, the output of the integrator 109 is controlled to converge to near zero quickly. Thus, the first image blur correction unit 107 and the second image blur correction unit 111 can be more strongly prevented from reaching the correctable limit.

  As described above, in the second embodiment of the present invention, when the outputs of the integrator 105 and the integrator 109 are further increased in addition to the processing of the first embodiment, the time constant of the integrator is obtained. Added a process to shorten. As a result, even when a large shake such as panning occurs, the two image shake correction units are further prevented from reaching the correctable limit, and immediately after the large shake such as panning converges, It is possible to perform optimal image blur correction control that returns to image blur correction.

(Third embodiment)
Next, an example of the operation of the image shake correction apparatus according to the third embodiment of the present invention will be described. FIG. 6 is a block diagram showing a configuration of an image shake correction apparatus 400 according to the third embodiment of the present invention. In the block diagram of FIG. 6, the same reference numerals are given to the blocks common to FIG.

  In FIG. 6, a motion vector detection unit 401 is a block that detects a motion vector from a luminance signal of a video generated based on an output of an imaging element (not shown) provided in an imaging device in which the image blur correction device 400 is mounted. It is. The panning control unit 112 performs panning determination based on the output of the angular velocity sensor 101 or the output of the motion vector detection unit 401, and changes the characteristics of the frequency separation unit 103 and the low frequency component attenuation unit 102.

  FIG. 7 is a flowchart showing a flow of processing executed by the panning control unit 112 in the third embodiment of the present invention. In the flowchart of FIG. 7, the processes common to those in FIG.

  In S300, the panning control unit 112 determines whether the output of the angular velocity sensor 101 is equal to or greater than a predetermined value. If it is determined in S300 that the output of the angular velocity sensor 101 is smaller than the predetermined value, the process proceeds to S301. In S301, the panning control unit 112 determines whether or not the motion vector output from the motion vector detection unit 401 is equal to or greater than a predetermined value. If it is determined in S301 that the motion vector output is smaller than the predetermined value, the process ends after performing the processes in S102 and S106. If it is determined in S300 that the output of the angular velocity sensor 101 is greater than or equal to a predetermined value, or if it is determined in S301 that the motion vector output is greater than or equal to a predetermined value, panning has been performed or a large shake has occurred. After determining that it has occurred and performing the processing of S103 and S107, this processing ends.

  The determinations in S300 and S301 are processes for detecting that a very large shake has occurred in the image shake correction apparatus 400. In this case, both the high-frequency angular velocity signal and the low-frequency angular velocity signal, which are the outputs of the frequency separation unit 103, become large outputs, and both the first image blur correction unit 107 and the second image blur correction unit 111 may reach the correction limit. There is sex. Therefore, in the flowchart of FIG. 7, when it is detected in S300 and S301 that a very large shake has occurred, the processing of S103 and S107 is performed to simultaneously limit the inputs to the integrator 105 and the integrator 109. doing. This prevents the first image blur correction unit 107 and the second image blur correction unit 111 from reaching the correctable limit even when a very large blur occurs in the image blur correction apparatus 400. .

  Note that the processing of S300 is not limited to using the output of the angular velocity sensor 101 for determination. For example, an angular acceleration signal obtained by differentiating the output of the angular velocity sensor 101 may be used for determination, or an integrated angle signal may be used for determination. Any process may be used as long as it is a determination using a signal based on the signal of the angular velocity sensor 101. Similarly, the process of S301 may be any process as long as it is a determination using a signal based on the motion vector output. Further, the process of S301 is not an essential process in the present embodiment. It is possible to detect that a large shake has occurred in the image shake correction apparatus 400 only by the process of S300, and the process of S301 is a process that plays an auxiliary role of S300.

  Moreover, this embodiment can also be combined with the second embodiment. Specifically, in the flowchart of FIG. 7, the processing of S200 and S202 may be performed after the processing of S106, and the processing of S201 and S203 may be performed after the processing of S107. As a result, when a large shake occurs in the image blur correction apparatus 400, the input to the integrator 105 and the integrator 109 is limited by the processing of S103 and S107, and at the same time, the integrator 105 and the processing of S201 and S203 are performed. The output of the integrator 109 can be easily converged near zero. As a result, even when a very large shake occurs in the image shake correction apparatus 400, the first image shake correction unit 107 and the second image shake correction unit 111 are more strongly prevented from reaching the correctable limit. be able to.

  As described above, in the third embodiment of the present invention, when the output of the angular velocity sensor 101 or the output of the motion vector detection unit 401 is increased, the separation frequency of the frequency separation unit 103 is increased, and The cut-off frequency of the low-frequency component attenuator 102 in the previous stage of the frequency separator 103 is increased. As a result, even when a very large shake such as a sharp panning occurs, the two image shake correction units are prevented from reaching the correction limit, and immediately after a large shake such as panning converges, It is possible to perform optimal image blur correction control that returns to the image blur correction.

  Although the present invention has been described in detail based on preferred embodiments thereof, the present invention is not limited to these specific embodiments, and various forms within the scope of the present invention are also included in the present invention. included. A part of the above-described embodiments may be appropriately combined.

(Other embodiments)
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, or the like) of the system or apparatus reads the program. It is a process to be executed.

Claims (11)

Shake detection means for detecting shake of the imaging device;
Low frequency component attenuation means for attenuating the low frequency component of the output of the shake detection means;
Separating means for separating the output of the low frequency component attenuating means into a low frequency signal and a high frequency signal;
First calculation means for calculating a first shake correction amount based on the high-frequency signal;
Second calculating means for calculating a second shake correction amount based on the low frequency signal;
First image shake correction means for correcting shake of a captured image based on the first shake correction amount;
Second image shake correction means for correcting shake of a captured image based on the second shake correction amount;
Control means for determining the movement of the imaging device based on the output calculated based on the high-frequency signal or the low-frequency signal and changing the control;
When the output calculated based on the high-frequency signal is equal to or greater than a predetermined value, the control means increases the separation frequency of the separation means,
An image blur correction apparatus, wherein when the output calculated based on the low frequency signal is equal to or greater than a predetermined value, the attenuation start frequency of the low frequency component attenuation means is increased.   The separation means sets the output of the high-pass filter as a high-frequency signal, sets the difference between the input signal and the high-frequency signal as a low-frequency signal, and the control means determines that the output calculated based on the high-frequency signal is a predetermined value or more. 2. The image blur correction apparatus according to claim 1, wherein a cutoff frequency of the high-pass filter is increased.   The separation means uses a low-frequency filter output as a low-frequency signal, a difference between the input signal and the low-frequency signal as a high-frequency signal, and the control means outputs an output calculated based on the high-frequency signal above a predetermined value. The image blur correction apparatus according to claim 1, wherein a cutoff frequency of the low-pass filter is increased.   The low frequency component attenuating means outputs a difference between a high-pass filter or an input signal and the output of the low-pass filter, and the control means, when the output calculated based on the low-frequency signal is a predetermined value or more, The image blur correction apparatus according to claim 1, wherein a cutoff frequency of the high-pass filter or the low-pass filter is increased. The first calculation means has a first integration means, and the second calculation means has a second integration means,
When the output calculated based on the high-frequency signal is equal to or greater than a predetermined value, the control means increases the separation frequency of the separation means and shortens the time constant of the first integration means,
When the output calculated based on the low frequency signal is greater than or equal to a predetermined value, the attenuation start frequency of the low frequency component attenuation means is increased and the time constant of the second integration means is shortened. The image blur correction apparatus according to any one of claims 1 to 4. Shake detection means for detecting shake of the imaging device;
Low frequency component attenuation means for attenuating the low frequency component of the output of the shake detection means;
Separating means for separating the output of the low frequency component attenuating means into a low frequency signal and a high frequency signal;
First calculation means for calculating a first shake correction amount based on the high-frequency signal;
Second calculating means for calculating a second shake correction amount based on the low frequency signal;
First image shake correction means for correcting shake of a captured image based on the first shake correction amount;
Second image shake correction means for correcting shake of a captured image based on the second shake correction amount;
Control means for determining the movement of the imaging device based on the output calculated based on the output of the shake detection means and changing the control;
The control means increases the separation frequency of the separation means and raises the attenuation start frequency of the low frequency component attenuation means when the output calculated based on the output of the shake detection means is equal to or greater than a predetermined value. An image blur correction apparatus characterized by that. It further has a motion vector detection means for detecting a motion vector from the captured image,
The control means increases the separation frequency of the separation means and sets the attenuation start frequency of the low frequency component attenuation means when the output calculated based on the output of the motion vector detection means is a predetermined value or more. The image blur correction device according to claim 6, wherein the image blur correction device is raised. A control method of an image shake correction apparatus including a shake detection unit that detects shake of an imaging apparatus,
A low frequency component attenuation step for attenuating the low frequency component of the output of the shake detection means;
A separation step of separating the output of the low frequency component attenuation step into a low frequency signal and a high frequency signal;
A first calculation step of calculating a first shake correction amount based on the high-frequency signal;
A second calculation step of calculating a second shake correction amount based on the low frequency signal;
A first image shake correction step of correcting shake of a captured image based on the first shake correction amount;
A second image shake correction step of correcting shake of the captured image based on the second shake correction amount;
A control step of determining the movement of the imaging device based on the output calculated based on the high-frequency signal or the low-frequency signal, and changing the control,
In the control step, if the output calculated based on the high-frequency signal is equal to or greater than a predetermined value, the separation frequency in the separation step is increased,
A control method for an image blur correction apparatus, wherein an attenuation start frequency in the low frequency component attenuation step is increased when an output calculated based on the low frequency signal is a predetermined value or more. A control method of an image shake correction apparatus including a shake detection unit that detects shake of an imaging apparatus,
A low frequency component attenuation step for attenuating the low frequency component of the output of the shake detection means;
A separation step of separating the output of the low frequency component attenuation step into a low frequency signal and a high frequency signal;
A first calculation step of calculating a first shake correction amount based on the high-frequency signal;
A second calculation step of calculating a second shake correction amount based on the low frequency signal;
A first image shake correction step of correcting shake of a captured image based on the first shake correction amount;
A second image shake correction step of correcting shake of the captured image based on the second shake correction amount;
A control step of determining the movement of the imaging device based on the output calculated based on the output of the shake detection means and changing the control;
In the control step, when the output calculated based on the output of the shake detecting means is a predetermined value or more, the separation frequency in the separation step is increased and the attenuation start frequency in the low frequency component attenuation step is set. A method for controlling an image blur correction apparatus, characterized by increasing the height.   The program for making a computer perform each process of the control method of Claim 8 or 9.   A computer-readable storage medium storing a program for causing a computer to execute each step of the control method according to claim 8 or 9.

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