JPH06169424A - Camera - Google Patents

Abstract

PURPOSE:To attain a highly precise correction of both a horizontal and vertical directional shake, and a rotary shake by adding an angle sensor in addition to an acceleration sensor in horizontal and vertical directions. CONSTITUTION:A microcomputer 21 adjusts a reading timing from a field memory 15 by controlling a read control part 20 for a hand shake correction based on hand shake amounts obtained by the acceleration in the horizontal and vertical directions obtained from a horizontal acceleration sensor 22 and a vertical acceleration sensor 23. Moreover, the microcomputer 21 corrects the shake caused by the rotation by adjusting the rotation of a picture based on rotation angle information obtained from an angle sensor 24. That is, the angle sensor 24 detects the rotation to + and - directions around X and Y axes against a camera, and corrects and outputs a picture signal rotated only at a rotation angle theta obtained by an imager so that the rotation can be denied.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly to a camera having a camera shake correction function. 2. Description of the Related Art Conventionally, in order to correct a deviation of a photographed image caused by camera shake during camera photographing, conventionally, a camera shake amount is detected by a sensor, and an image signal is shifted by an amount corresponding to the detected camera shake amount. I am letting you. For example, in an NTSC imager having a size as shown in FIG. 15A, the effective area displayed on the television monitor is a shaded area, and image signals other than the shaded area are normally ignored. The camera shake correction uses the image signal other than the shaded area by the amount corresponding to the camera shake amount detected by the sensor. For example, when camera shake occurs in the lower right direction, the image signal in the upper left diagonal line portion is taken out as shown in FIG. 7B, and when camera shake occurs in the upper left direction, the lower right diagonal line is shown in FIG. The image signal of a part is taken out so that the effect of camera shake does not appear in the resulting image signal. FIG. 16 is a schematic block diagram of a conventional camera having a camera shake correction function. A video signal of a subject formed on an imager 102 such as a CCD having 768 × 492 pixel configuration through the optical system 101 is obtained from a known image pickup process circuit 103 and supplied to a recording system. The reference timing signal is supplied from the timing signal generation circuit 104 to the imager 102 and the imaging process circuit 103. A signal generation circuit 1 that receives the timing signal
From 05, a predetermined signal for image pickup processing is sent to the image pickup process circuit 103. Horizontal acceleration sensor 10
7 and the vertical direction acceleration sensor 108 detect horizontal and vertical accelerations and use them as basic data for detecting the amount of camera shake. The camera shake detection / correction timing generation circuit 106 controls the timing signal generation circuit 104 based on the basic data, and performs camera shake correction control as described below. FIG. 17 is a timing chart for explaining the conventional camera shake correction operation. Vertical sync signal VSY
Blanking signal VBLK in synchronization with NC (A)
(B) occurs, and the image signal (D) is read from the imager (CCD). In the same figure (C), a section T1 in which no camera shake occurs and a section T in which camera shake occurs upward
2 is shown, and the video signal read from the CCD in each section is shown in (D). When camera shake occurs, the read timing of the imager is adjusted according to the amount of camera shake. In the section T1 where camera shake does not occur,
Image signal (D) from the imager without any correction #
1 is read out to obtain an output image # 11 as shown in (F). In the section T2 in which the upward shake occurs, the picture is displayed downward like # 2 or # 3 as shown in # 12 of (C). When such a camera shake occurs, the read timing from the imager is adjusted as shown in (E). In this example, the image signals of # 2 and # 3 have a camera shake amount of 1
Image signals of 2H and 24H are shown, and the image is read at a timing that is 12H ahead of the camera shake for which the # 2 image signal is obtained, and is read at a timing that is 24H ahead of the camera shake for which the image signal of # 3 is obtained. By adjusting the read timing from the imager in this way, # 2 and # 3
As shown in # 12 and # 13 of FIG. 7F, the image signal displayed below due to the camera shake is
It is corrected so that it is displayed at the center position. At this time,#
For the image signal of No. 3, the adjustment of the read timing becomes too large, so that the display image cannot be obtained from the pixels of the imager, and the picture may be cut off. As described above, in the image stabilization in the conventional camera, the read timing from the imager is adjusted based on the amount of camera shake in the horizontal and vertical directions obtained by the sensor. ing. However, camera shake does not only occur in the horizontal and vertical directions as described above, but there are also camera shakes caused by rotation around the optical axis of the camera. The above-described conventional camera cannot cope with this rotational shake, and sufficient camera shake correction has not been performed. Therefore, an object of the present invention is to provide a camera capable of highly accurately correcting not only horizontal and vertical blurring but also rotation blurring. In order to solve the above-mentioned problems, the camera according to the present invention provides a sensor means for detecting the attitude of the camera and the screen effectively, in the normal horizontal scanning direction. And a means for obtaining a video signal output scanned in a direction forming an angle corresponding to the detection output of the sensor means. According to the present invention, not only the amount of camera shake in the horizontal and vertical directions of the camera is detected to correct the image shift caused by the camera shake, but also the rotation angle is detected and the detected rotation is detected. The rotation deviation of the image due to the rotation is also corrected based on the angle. Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a camera according to the present invention. In FIG. 1, an image formed on a CCD (imager) 12 via an optical system 11 such as a lens is converted into an electric signal by the CCD 12 and converted into a digital signal by an A / D converter 13. The digital signal is subjected to well-known predetermined signal processing in the imaging process unit 14, separated into a Y signal and a C signal, and written in the Y field memory and the C field memory of the field memory 15. The Y signal and C signal read from the field memory 15 are subjected to Y interpolation processing and C interpolation processing in the interpolation processing unit 16 and output to the recording system. Various sync signals are generated from the sync signal generator 17, the timing signal generator 18 is driven to control the operation of the CCD 12, the operation timing of the imaging process unit 14 is controlled, and the field is transmitted via the light control unit 19. The write timing for the memory 15 is controlled. The horizontal acceleration sensor 22 and the vertical acceleration sensor 23 detect horizontal and vertical accelerations, and the angle sensor detects rotation angle information about the X and Y axes.
The A / D converter 21A is built in the microcomputer 21,
The information from the sensors 22, 23 and 24 is converted into digital signals. The microcomputer 21 controls the read control unit 20 based on these pieces of information, and controls the address signal Add and the interpolation coefficient k supplied to the field memory 15 and the interpolation processing unit 16 to correct the camera shake. As shown in FIG. 2, the selector 25 can select any of the three sensors 22, 23 and 24 by operating a switch, and can correct the situation without using any of them. Becomes That is, the mode # 1 in which the operation of all the sensors is turned off, and the mode # in which only the acceleration information from the acceleration sensors 22 and 23 is used.
2, each mode cyclically changes in order of mode # 3 using only the angle information from the angle sensor 24 and mode # 4 using both the acceleration information and the angle information.
By using this selector, it is possible to perform the optimum fine blur correction for each. In the above, the microcomputer 21 controls the lead control unit 20 for camera shake correction based on the camera shake amount obtained from the horizontal and vertical accelerations obtained from the horizontal acceleration sensor 22 and the vertical acceleration sensor 23. The read timing from the field memory 15 is adjusted. This adjustment is performed in the same manner as described with reference to FIGS. In the present embodiment, the image is rotated and adjusted based on the rotation angle information obtained from the angle sensor 24 to correct the blur caused by the rotation. FIG. 3 shows an example of the angle sensor 24. As shown in (A) of the figure, the angle sensor 24 has a + and −
The rotation in the direction and the-direction is detected. In the figure, 110
Is a lens and 120 is a viewfinder. Camera 10
Rotation in the + and − directions about the Y axis as viewed from the front of 0 is shown in (B). Using the rotation angle θ obtained by the angle sensor 24, the image signal rotated by θ obtained from the imager is corrected and output so as to cancel this rotation. The principle of address conversion for controlling the rotation of the subject image will be described with reference to FIG. FIG. 4 shows an address positional relationship when an original image shown by a thin line is rotated by θ to obtain a thick line image by oblique scanning. In the figure, white circles represent real pixels stored in the memory, and black circles represent virtual pixels read from the memory. Each address position P
(00), P (10), P (20), P (01), P
(11), P (21), P (02), P (12), P
(22) Corresponding pixel data is written in the field memory 6, and the pixel data at these address positions are used to rotate by θ with respect to the position P (00) as the corresponding address position Q ( 10), Q (20), Q
(01), Q (11), Q (21), ... Are obtained and sent to the field memory 6 as the address signal Add. For example, the address position Q (1
The virtual pixel addresses of 0), Q (20), Q (01), Q (11) are obtained as follows from the relationship shown in the figure. Q (10): x ... P (00) + cos θ y ... P (00) + sin θ Q (20): x ... P (00) +2 cos θ = P (10) +2 cos θ-1 y ... P (00) +2 sin θ = P (10 ) +2 sin θ Q (01): x ... P (00) -sin θ y ... P (00) + cos θ Q (11): x ... P (00) -sin θ + cos θ = P (01) -sin θ + cos θ y ... P (00) + cos θ + sin θ = P (01) + cos θ + sin θ−1 FIG. 5 shows an example of a circuit for generating the X address. A pixel address to be read first, 0 in this example, is set in the XST register 151X, and XW
XW = cos θ shown in FIG. 4 is generated from the register 152X and X shown in FIG. 4 is generated from the X0 register 153X.
0 = −sin θ has been generated. The output of the adder 154X is delayed by one clock (for one pixel) by the delay device 156X. The adder 154X adds the cos θ from the XW register 152X and the output from the delay device 156X.
The output of the delay device 156X is added to the output (0 in this example) from the XST register 151X in the adder 158X. The delay device 157X outputs the output of the adder 155X to 1
Delay by H. The adder 155X is the X0 register 15
The −sin θ from 3X and the output from the delay device 157X are added. The adder 159X adds the output of the delay device 157X and the output of the adder 158X and outputs the result as an X address signal. FIG. 6 shows an example of a circuit for generating a Y address signal similar to that shown in FIG. YST register 151Y
Is set to 0, the YW register 152Y generates YW = sin θ shown in FIG. 4, and the Y0 register 15Y
From 3Y, Y0 = cos θ shown in FIG. 4 is generated.
The output of the adder 154Y is delayed by one clock (one pixel) by the delay device 156Y. The adder 154Y adds sin θ from the YW register 152Y and the output from the delay device 156Y. The output of the delay device 156Y is the output from the YST register 151Y (0 in this example) and the adder 1
58Y is added. The delay device 157Y is the adder 1
The output of 55Y is delayed by 1H. The adder 155Y is
Cos θ from the Y0 register 153Y and the delay device 157
Add the output from Y. The adder 159Y adds the output of the delay device 157Y and the output of the adder 158Y and outputs the result as a Y address signal. By changing the setting values of the XST register 151X and the YST register 151Y, it is possible to correct the blurring in the horizontal and vertical directions, and the XW register 152X,
The rotation angle is adjusted by changing the set values of the YW register 152Y, the X0 register 153X, and the Y0 register 153Y. In this embodiment, further effects can be obtained by using it together with the electronic zoom function. That is, when the original image is rotated, blanking signals appear at the four corners and are displayed in black. However, if the central part is enlarged by electronic zoom, the blanking signals are prevented from being displayed on the monitor. . FIG. 7 shows the principle of address conversion shown in FIG. 4 and the aspect ratio of 3 to 4 shown in FIG. 8 (768 pixels, 2
(40 lines) and the address conversion diagram when rotated by 30 degrees is shown. In this case, as shown in FIG. 8, one pixel has a horizontal and vertical size of 2.4: 1. At this time, XST = 0 XW = 0.866 X
0 = −2.4 × 0.5 YST = 0 YW = 0.5 / 2.4 Y0 = 0.8
66, and as is clear from the figure, the general formula expressing the X address Xmn and the Y address Ymn when the number of pixels is m and the number of lines is n is as follows. Xmn = XST + m * XW + n * X0 Ymn = YST + m * YW + n * Y0 For example, the address (coordinates) of the 0th line (n = 0) is
(XY) = (0,0), (0.866,0.208),
(1.732, 0.417), ... In the first line (n = 1), (XY) = (-1.2,
0.866), (-0.334, 1.074), (0.
532, 1.28), ... Here, it is clear from the figure that the integer part of each address indicates the address Add and the decimal part indicates the interpolation coefficient K. For the above-mentioned interpolation processing, it is preferable to use a four-point weighting method as shown in FIG. 9, for example. The address position Q to be read from the memory is determined by defining X1 and X2 as shown in the figure, and the four surrounding points P (11), P (21), P (1
2), using the weighted average of P (22), it is calculated by the following formula. Q = (1-Ky) X1 + Ky * X2 X1 = (1-Kx) P (11) + KxP (21) X2 = (1-Kx) P (12) + KxP (22) Therefore, Q = (1-Kx) ( 1-Ky) P (11) + Kx (1-Ky) P (21) + Ky (1-Kx) P (12) + Kx · Ky · P (22) (1) The operation of the formula (1) is one cycle. 4 pixel address P in
This can be realized by reading (11), P (21), P (12), and P (22) at the same time. The simultaneous reading of the four pixels can be performed using a memory configuration as shown in FIG. 10, for example. In the example shown in FIG. 10, even columns are arranged so that four pixels can be read by supplying an address once.
Even row dedicated memory (A), odd column, even row dedicated memory (B), even column, odd row dedicated memory (C) and odd column,
Four independent memories of the odd row memory (D) are provided. FIG. 11 shows an address generation circuit for reading data from the memory for performing the arithmetic operation by the above-mentioned four-point weighted average circuit. An address, a column address for even column memory, a row address for odd row memory, and a row address for even row memory are generated. 0 for column address
The bits are output as the select signal HSEL and added by the adder 251 with bits 1 to 9. 1 to
9 bits become the column address for the odd column memory, and the adder 2
The output of 51 becomes the column address for even column memory. Similarly, 0 bit of the row address is output as the select signal VSEL and is added by the adder 252 with 1 to 7 bits. Bits 1 to 7 become the row address for the odd row memory, and the output of the adder 252 becomes the row address for the even row memory. FIG. 12 shows an example of a circuit for performing the 4-point weighted average calculation shown in the equation (1) using the read data read from the memory. In FIG. 12, the selectors 253 and 254 are the select signals HS obtained in FIG.
When EL is "H", the "H" terminal is selected, and when it is "L", the "L" terminal is selected, and the selector 261 similarly selects the corresponding terminal by the select signal VSEL. Even-numbered-column even-row read data and odd-numbered-column even-row read data are input to the selector 253, and the selector 254 receives
Even-numbered column odd-row read data and odd-numbered column odd-row read data are input. The two outputs from the selector 253 are multiplied by the coefficients (1-K
x) and Kx are multiplied. The outputs of the multipliers 255 and 256 are added by the adder 257 and output to the 2-input terminal (L, H) of the selector 261. On the other hand, the two outputs from the selector 254 are multiplied by the coefficients (1-Kx) and Kx by the multipliers 258 and 259, respectively. Multiplier 258
The outputs of and 259 are added by the adder 260 and output to the other two input terminals (L, H) of the selector 261. The two outputs from the selector 261 are X1 and X2 described above, and the multipliers 262 and 263 respectively output the coefficient (1-K
x) and Kx are multiplied. The outputs of the multipliers 262 and 263 are added by the adder 264 to obtain the interpolated data Q. In the examples of FIGS. 11 and 12, the select signal is necessary because, as shown in FIG. 13, four address points to be selected are generated in accordance with four patterns # 1 to # 4. In this example, pattern # 2 is shown. Now, the rotation deviation in the X direction or the Y direction is corrected for the image that has been subjected to the rotation correction as described above. The operation timing of this correction process is shown in FIG. FIG. 14 shows a case where the camera shake in the vertical (Y) direction is corrected. The vertical blanking signal (B) is generated in synchronization with the vertical synchronizing signal VSYNC (A). As shown in FIG. 7C, a section T1 in which camera shake does not occur, a section T2 that is displaced 11H upward due to camera shake, and a section 11H below
The image signal written in the memory in the shifted section T3 is shown in (D). Section T where camera shake does not occur
1, the read address from the memory is YST in FIG.
By setting "0" in the register 151Y, the normal operation is set to 0 to 239 (# 1), and when the upward shake of 11H occurs, the read address is set by setting "11" in the YST register 151Y. 11-251
(# 2), and when a downward shake of 11H occurs,
By setting "-11" in the YST register 151Y, the read addresses are set to -11 to 233 (# 3). Therefore, the image signals read by the read addresses # 1, # 2 and # 3 are # 11 and # shown in (F).
12 and # 13 are corrected to the central position. As described above, according to the camera of the present invention, it is possible to correct not only the image shift caused by the horizontal and vertical camera shake but also the shift caused by the rotation. A high-quality image intended by the user can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration block diagram showing an embodiment of a camera according to the present invention. FIG. 2 is a diagram showing an operation mode selected by a selector 25 in the embodiment of FIG. FIG. 3 is a diagram illustrating an angle sensor in the embodiment of FIG. FIG. 4 is an address generation principle diagram showing an image rotation principle in the embodiment of the present invention. FIG. 5 is a circuit diagram for generating an X address according to the principle diagram shown in FIG. FIG. 6 is a circuit diagram for generating a Y address according to the principle diagram shown in FIG. FIG. 7 is a diagram showing an address generation principle when the principle shown in FIG. 4 is applied to actual image rotation. 8 is an image configuration diagram which is a basis of the principle diagram shown in FIG. 7. FIG. FIG. 9 is a principle diagram of performing interpolation processing by an interpolation processing circuit 7 according to an embodiment of the present invention by a 4-point weighted average calculation. 10 is a block diagram of a memory used to perform the interpolation process shown in FIG. 9. FIG. 11 is a circuit diagram showing an example of a memory read address generation circuit used in the interpolation processing shown in FIG. 9; 12 is a circuit diagram showing an example of the interpolation processing shown in FIG. 13 is a diagram showing an example of an even / odd combination of four points selected in the interpolation processing shown in FIG. FIG. 14 is a timing diagram illustrating the operation of the embodiment according to the present invention. FIG. 15 is a diagram for explaining an example of image stabilization using an imager image area. FIG. 16 is a configuration block diagram of a camera having a conventional camera shake correction function. FIG. 17 is a timing diagram illustrating a conventional camera shake correction operation. [Description of reference numerals] 11 optical system 12 imager 13, 21A A / D converter 14 imaging process unit 15 field memory 16 interpolation processing unit 17 synchronization signal generating unit 18 timing signal generating unit 19 write control unit 20 read control unit 21 Microcomputer 22 Horizontal acceleration sensor 23 Vertical acceleration sensor 24 Angle sensor 25 Selector

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[Procedure amendment] [Date of submission] November 12, 1993 [Procedure Amendment 1] [Document name for amendment] Specification [Item name for amendment] Brief explanation of drawings [Amendment method] Change [Amendment content] [ BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration block diagram showing an embodiment of a camera according to the present invention. FIG. 2 is a diagram showing an operation mode selected by a selector 25 in the embodiment of FIG. FIG. 3 is a diagram illustrating an angle sensor in the embodiment of FIG. FIG. 4 is an address generation principle diagram showing an image rotation principle in the embodiment of the present invention. FIG. 5 is a circuit diagram for generating an X address according to the principle diagram shown in FIG. FIG. 6 is a circuit diagram for generating a Y address according to the principle diagram shown in FIG. FIG. 7 is a diagram showing an address generation principle when the principle shown in FIG. 4 is applied to actual image rotation. 8 is an image configuration diagram which is a basis of the principle diagram shown in FIG. 7. FIG. FIG. 9 is a principle diagram of performing interpolation processing by an interpolation processing circuit 7 according to an embodiment of the present invention by a 4-point weighted average calculation. 10 is a block diagram of a memory used to perform the interpolation process shown in FIG. 9. FIG. 11 is a circuit diagram showing an example of a memory read address generation circuit used in the interpolation processing shown in FIG. 9; 12 is a circuit diagram showing an example of the interpolation processing shown in FIG. 13 is a diagram showing an example of an even / odd combination of four points selected in the interpolation processing shown in FIG. FIG. 14 is a timing diagram illustrating the operation of the embodiment according to the present invention. FIG. 15 is a diagram for explaining an example of image stabilization using an imager image area. FIG. 16 is a configuration block diagram of a camera having a conventional camera shake correction function. FIG. 17 is a timing diagram illustrating a conventional camera shake correction operation. [Explanation of Codes] 11 Optical System 12 Imager 13, 21A A / D Converter 14 Imaging Process Section 15 Field Memory 16 Interpolation Processing Section 17 Sync Signal Generation Section 18 Timing Signal Generation Section 19 Write Control Section 20 Read Control Section 21 Microcomputer 22 Horizontal Directional acceleration sensor 23 Vertical direction acceleration sensor 24 Angle sensor 25 Selector

Claims (1)

Claim: What is claimed is: 1. An image obtained by effectively scanning a sensor means for detecting the attitude of the camera and the screen in a direction that forms an angle with the normal horizontal scanning direction according to the detection output of the sensor means. A camera having means for obtaining a signal output.