JP2007110636A - Camera apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera apparatus capable of photographing a still picture with high image quality by suppressing a camera shake in photographing the still picture without using a strobe unit at a place wherein the luminous quantity is insufficient. <P>SOLUTION: When the luminous quantity around an object is small, a signal processing section 4 controls a frequency multiplier section 5 to decrease an exposure time of an imaging element 2, the signal processing section 4 produces a plurality of pictures on the basis of electric signals output from the imaging element 2, and an image composite section 7 synthesizes the pictures output from the signal processing section 4 to produce one picture. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera device having a camera shake correction function.

  As a factor that greatly affects image quality when taking a still image, image quality degradation due to camera shake caused by the hand holding the camera is widely known. Recently, digital cameras that have become mainstream are generally composed of a lens, an image sensor such as a CCD (photoelectric conversion element) or a CMOS sensor, a signal processing circuit, an information medium, and the like. The information is imaged and imaged on the imaging surface of the imaging element. At this time, in order to convert optical information into electrical information by the image sensor, an electronic shutter function for controlling the optical signal to form an image on the imaging surface of the image sensor for a certain period is required. If camera shake occurs during the shutter time of the electronic shutter (time during which the image sensor is exposed), the imaging position on the image sensor is shifted, and a blurred image is captured.

  In recent years, a large number of camera devices having a camera shake correction function have been commercialized, centering on video cameras capable of shooting moving images. By using this camera shake correction function, image quality deterioration due to camera shake is reduced.

  Two types of camera shake correction methods are widely known: “optical camera shake correction” and “electronic camera shake correction”. First, optical camera shake correction is a method in which a lens or an image sensor is physically moved in a direction orthogonal to the optical axis to cancel the shake of the optical axis due to camera shake. Optical camera shake correction is capable of highly accurate correction, but requires a movable member for moving a lens and an image sensor, and is not suitable for downsizing and cost reduction.

  Electronic camera shake correction is to correct camera shake by applying digital signal processing to the output signal of the image sensor. Since electronic image stabilization can be realized entirely by digital signal processing, it is suitable for downsizing and cost reduction.

  A conventional camera device equipped with an electronic camera shake correction function will be described below.

  FIG. 9 is a block diagram showing the configuration of a conventional camera device. In the figure, the camera unit 3 includes a lens 1 and an image sensor 2. The image sensor 2 is composed of a CCD, a CMOS sensor or the like. An optical signal incident on the image sensor 2 via the lens 1 is photoelectrically converted in the image sensor 2 and an electric signal is output. An electrical signal output from the image sensor 2 is input to an analog-to-digital converter (hereinafter referred to as ADC) 14 and converted into a digital signal, and then input to a signal processing circuit 4 (hereinafter referred to as DSP). In the DSP 4, general signal processing such as noise removal and image quality adjustment is performed on an input signal, and motion compensation (camera shake correction) processing is performed to output an image signal. The image signal output from the DSP 4 is displayed on the display unit 13 including, for example, a liquid crystal display, and is output to the still image signal processing circuit 9. Note that the image is output to the still image signal processing circuit 9 only when a photographer inputs a shooting command by operating a shutter button (not shown) or the like. The image signal input to the still image signal processing circuit 9 is subjected to compression processing and the like, and is recorded on the information medium 10.

  Next, the principle of occurrence of camera shake in the camera device will be described.

  FIG. 10A (a) is a schematic diagram showing the mechanism of occurrence of camera shake in a still image. FIG. 10B (a) is a timing chart showing the shutter speed when the subject is sufficiently bright. FIG. 10C (a) is a timing chart showing the shutter speed when the subject is dark. Each diagram (b) is a schematic diagram showing an image captured by the image sensor 103.

  As shown in FIG. 10A, the optical information of the incident subject 101 is imaged on the imaging surface of the imaging element 103 by the lens 102, so that a still image can be taken. When camera shake does not occur in the camera apparatus at the time of shooting, the camera device passes through the center of the lens 102 as shown by the optical axis 104a and is positioned at the approximate center of the imaging surface of the imaging device 103. However, when camera shake occurs in the camera device, the camera device is distorted as indicated by the optical axis 104b, and is largely deviated from the center of the imaging surface of the image sensor 103. As a result, the image signal obtained from the image sensor 103 becomes a blurred image 105 as shown in FIG.

  Also, when the amount of light of the subject is sufficiently bright, the shutter speed is controlled to be short as shown in FIG. 10B (a), so even if camera shake occurs during shooting, it is shown in (b). Thus, the influence on the image is small, and the image 105a is inconspicuous.

  However, when the subject is dark and the amount of light is insufficient, the shutter speed is controlled to be slow as shown in FIG. 10C (a). When the shutter speed becomes slow and the shutter time becomes long, there is a large time difference between the imaging timing at the start of imaging (Ta in the figure) and the imaging timing at the end of imaging (Tb in the figure). Then, the image 105b of (b) is captured at the timing Ta, whereas the image 105c whose imaging position is shifted due to camera shake is captured at the timing Tb. An image 105d obtained from the image sensor 103 by adding these images 105b and 105c is lost and the image quality is deteriorated. In such a case, generally, in order to avoid camera shake, a technique is often used in which a strobe is emitted to increase the amount of light of the subject and to shorten the shutter time.

On the other hand, there is little influence from camera shake during movie shooting. That is, as shown in FIG. 11A, a still image is shot at a frame period (1/30 second) during moving image shooting. Therefore, camera shake that occurs during moving image shooting seems to overlap each still image by the afterimage effect, as shown in FIG. For such camera shake, as shown in (c), camera shake can be corrected by performing a process of shifting the position of each frame so that the position of the subject of each frame matches (for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-200809

  However, in the above-described conventional configuration, if still image shooting is performed without using a strobe device in a place where the amount of light is insufficient, such as shooting night scenes or fireworks, the shutter speed is controlled to be slow, and as shown in FIG. 10C. In addition, there is a problem that image quality deteriorates due to camera shake.

  In view of the above problems, the present invention provides a camera device capable of shooting a high-quality still image with reduced camera shake when shooting a still image without using a strobe device in a place where the amount of light is insufficient. Objective.

  In order to solve the above problems, a camera device of the present invention generates an image signal based on an image sensor that converts an optical signal incident via a lens into an electric signal, and an electric signal output from the image sensor. In addition, a signal processing unit that outputs an operation clock of the imaging device, a display unit that can display a video signal output from the signal processing unit, and a video signal output from the signal processing unit can be recorded or reproduced. And a camera device capable of photographing at least a still image by operating a shutter button, and capable of multiplying a frequency of an operation clock output from the signal processing unit and input to the imaging device. Based on the frequency multiplier, the camera shake detector capable of detecting camera shake of the camera device, and the camera shake detected by the camera shake detector, the signal processor outputs the camera shake. A motion compensation unit that shifts a frame of a still image and compensates for the motion of the image, and an image synthesis unit that can generate a single still image by superimposing a plurality of images output from the motion compensation unit. And when the amount of light in the subject is small, the frequency multiplying unit multiplies the frequency of the operation clock so that the exposure time of the image sensor is shortened, and a plurality of sheets based on the electrical signal output from the image sensor The image synthesizing unit generates a single image by synthesizing a plurality of images output from the signal processing unit.

  According to the present invention, even when the subject is dark and the amount of light is insufficient, it is possible to shoot a high-quality still image in which the influence of camera shake is suppressed.

  The camera device of the present invention further includes a camera shake detection unit capable of detecting camera shake of the camera device, and the motion compensation unit performs motion compensation of an image based on camera shake information detected by the camera shake detection unit. It is good.

  Further, the camera shake detection unit may be constituted by an angular velocity sensor.

  The signal processing unit may be configured to detect camera shake based on the frame correlation of the generated video signal.

  Further, the motion compensation unit may be configured to divide the image output from the signal processing unit into a plurality of blocks and to perform motion compensation processing on each of the divided blocks.

  The image composition unit may be configured to selectively perform image composition or non-composition processing on each block divided by the motion compensation unit.

(Embodiment 1)
FIG. 1 is a block diagram illustrating a configuration of the camera device according to the first embodiment.

  In FIG. 1, a camera unit 3 includes a lens 1 including a zoom lens, a focus lens, and the like, and an image sensor (imaging device) 2 that photoelectrically converts an incident optical signal into an electrical signal. The image sensor 2 is composed of, for example, a CCD or CMOS sensor, and will be described below by taking the CCD as an example. A signal processing circuit (hereinafter referred to as DSP) 4 performs general signal processing such as noise removal and image quality adjustment on the image signal converted into a digital signal by the ADC 14. The frequency multiplier 5 multiplies the clock output from the DSP 4 and changes the operating frequency of the image sensor 2.

  The camera shake detection unit 18 detects camera shake of the camera device main body, and is configured by, for example, an angular velocity sensor. Information on the detected camera shake is output to the camera shake correction circuit 8.

  The camera shake correction circuit 8 includes a motion compensation circuit 6 that performs motion compensation processing on the image signal output from the DSP 4 based on the camera shake information output from the camera shake detection unit 18, and a plurality of motion-compensated image signals. And an image synthesizing circuit 7 for synthesizing.

  The still image signal processing circuit 9 performs signal processing such as image compression on the image signal output from the camera shake correction circuit 8.

  The information medium 10 records the image signal output from the still image signal processing circuit 9. The information medium 10 includes, for example, a memory card equipped with a semiconductor memory. However, the information medium 10 is not limited to this, and may be a disk-shaped medium or a tape-shaped medium.

  The frame thinning unit 11 thins out a predetermined amount of the image signal output from the DSP 4. The display unit 12 can display a display image signal output from the thinning unit 11, and is configured by a liquid crystal display of about 2 to 4 inches, for example.

  The operation of the embodiment configured as described above will be described below.

  In FIG. 1, an optical signal incident on an image sensor 2 through a lens 1 is photoelectrically converted in the image sensor 2 and an electric signal is output. The electrical signal output from the image sensor 2 is input to the ADC 14 and converted into a digital signal, and then input to the DSP 4. The DSP 4 performs signal processing such as noise removal and image quality adjustment on the input signal. The image signal output from the DSP 4 is subjected to a thinning process by the thinning unit 11 (the thinning process will be described later) and displayed on the display unit 13. The image signal output from the DSP 4 is also input to the camera shake correction circuit 8.

  On the other hand, the camera shake detection unit 18 detects camera shake occurring in the camera apparatus body, and outputs the camera shake information to the camera shake correction circuit 8. The camera shake information output from the camera shake detection unit 18 is information including the movement direction and the amount of movement of the camera device caused by the camera shake.

  In the motion compensation circuit 6 of the camera shake correction circuit 8, based on the camera shake information output from the camera shake detection unit 18, a motion compensation process (a specific processing method will be described later) of the image signal that cancels the camera shake is performed. . The motion-compensated image signal is output to the image synthesis circuit 7 and a plurality of frames of image signals are synthesized to generate one still image.

  The image signal output from the camera shake correction circuit 8 is input to the still image signal processing circuit 9. In the still image signal processing circuit 9, compression processing or the like is performed on the image signal. The image signal output from the still image signal processing circuit 9 is recorded on the information medium 10.

  Next, an image capturing operation at the time of shooting will be described with reference to FIG. FIG. 2 is a timing chart showing an operation from when the shutter button is operated until an image signal is output. (A) shows a conventional shutter operation, and (b) shows a shutter operation shown in (a). (C) shows the operation when the shutter time is long in the conventional operation, (d) shows the image signal taken by the shutter operation shown in (c), and (e) shows the image signal taken. The shutter operation of this embodiment is shown, and (f) shows an image signal imaged by the shutter operation shown in (e). In FIG. 2, A1 to A4 indicate still images (frames).

  As shown in FIG. 1, optical information of a subject is imaged on an image sensor 2 via a lens 1, converted into an electrical signal by photoelectric conversion processing, and output as an image signal (still image). In the conventional camera device, when the shutter button is operated once as shown in FIG. 2A, the image sensor 2 picks up the image for the period shown in S11, and one still image as shown in FIG. 2B. A1 is output from the image sensor. If the amount of light of the subject is insufficient, the amount of light is increased by taking a picture with a longer shutter time as shown in the shutter time S12 of FIG. However, as described above, the longer the shutter time, the more easily affected by camera shake, the possibility that the still image A1 in FIG. 2D is a blurred image is high.

  In the present embodiment, as shown in FIG. 2 (e), control is performed so that a plurality of still images are output from the image sensor with a single shutter button operation. That is, control is performed so that a plurality of still images are continuously photographed by dividing a shutter time that becomes long when the amount of light of the subject is insufficient into short shutter times. In the shutter operation shown in FIG. 2E, the shutter time is divided into four as shown in S1 to S4. Each shutter time in FIG. 2 (e) is set to a time equivalent to the shutter time S11 shown in FIG. 2 (a), and is set to a shutter speed that is not easily affected by camera shake.

  By taking a picture with the shutter time shown in FIG. 2E, it is possible to take a picture with a fast shutter time even if the amount of light of the subject is insufficient, so that four still images A1 to A4 with reduced camera shake are obtained. be able to. Further, since the time required for shooting the shutter times S1 to S4 is secured to the same time as the shutter time S12 shown in FIG. 2C, one still image is generated based on the still images A1 to A4. Thus, a bright still image can be obtained.

  Next, still image motion compensation will be described with reference to FIG.

  FIG. 3 is a schematic diagram showing an image signal captured by the control shown in FIGS. 2D and 2E, and the face in the figure corresponds to the subject. FIG. 3 (a) is the first one of the above-described still images taken and corresponds to the still image taken at the timing S1 in FIG. 2 (e). As shown in FIG. 3A, the subject is located substantially at the lower right of the angle of view. FIG. 3B shows the second still image, which corresponds to the still image taken at the timing S2 in FIG. As shown in FIG. 3B, the subject is located at the approximate center of the angle of view. As shown in FIGS. 3A and 3B, although the same subject is continuously photographed, the position of the subject in the frame varies depending on the camera shake.

  When the still images in FIGS. 3A and 3B are simply overlaid, the subject is overlaid as shown in FIG. 3C, resulting in a slower shutter speed. In the same way as this, the image quality is deteriorated.

  However, if the still image shown in FIG. 3B is subjected to a process of shifting the frame in the direction of arrow A so as to compensate for the movement of the subject due to camera shake as shown in FIG. As shown in FIG. 3E, images can be synthesized without being affected by camera shake even when still images are superimposed. This is the motion compensation process. As methods for calculating image data by motion compensation, “nearest neighbor method”, “bilinear method”, “bicubic method” and the like are known.

  Next, a flow of a series of processes will be described with reference to FIG.

  When the shutter button is operated at the timing shown in FIG. 4A, conventionally, after the charge is accumulated by exposing light from the subject during the shutter time shown in FIG. 4B, FIG. In this embodiment, as shown in FIG. 4D, the shutter time (exposure time) is divided into a plurality of (for example, four), and each is output as an image signal (one frame). The result of charge accumulation is output as an image signal, and a still image is output a plurality of times at the timing shown in FIG. As shown in the figure, since the image signal accumulated during the shutter time is output, the output timing of the image signal is delayed compared to the shutter period shown in FIG. The image signal output as shown in FIG. 4 (d) is subjected to signal processing by the DSP 4, and then temporarily stored in the memory 15 as shown in FIG. 4 (f). The image data stored in the memory 15 undergoes motion compensation processing and image composition processing at the timing shown in FIG.

  In FIG. 4F, since the first still image (frame 1) is a reference still image, the motion compensation process and the image synthesis process are performed for the second and subsequent sheets as shown in FIG. It is applied to the image data (frames 2 to 4). When the synthesis of the fourth image is completed, the still image synthesis process is completed, and one still image is obtained.

  Next, camera shake detection of the camera device will be briefly described with reference to FIG.

  FIG. 5A is a schematic diagram showing a lens barrel in the camera device. In FIG. 5A, it is assumed that the cylindrical surface on the front side faces the subject side. The Z axis corresponds to the optical axis of a lens disposed in the lens barrel.

  Camera shake occurs with respect to the direction of rotation about the X axis or Y axis with respect to the camera (lens barrel) in FIG. 5A. The camera shake generated with respect to the X axis is a vertical shake with respect to the captured image, and the camera shake generated with respect to the Y axis is a horizontal shake with respect to the captured image.

  One method for detecting camera shake uses an angular velocity sensor. By installing two angular velocity sensors on the X axis and the Y axis in the vicinity of the lens barrel or in the vicinity of the lens barrel, it is possible to detect a vertical blur and a horizontal blur of the captured image.

  In the present embodiment, as shown in FIG. 5B, an angular velocity sensor 16 that detects shake in the X-axis direction and an angular velocity sensor 17 that detects shake in the Y-axis direction are installed in the camera unit 3 (inside the lens barrel). Thus, camera shake in the vertical direction and the horizontal direction of the camera unit 3 can be detected. Based on the camera shake detection result, the motion compensation circuit 6 can perform motion compensation for camera shake. In FIG. 5B, the configuration other than the angular velocity sensors 16 and 17 is the same as the configuration shown in FIG.

  As shown in FIG. 6, a method for detecting camera shake by signal processing of image data is also known. In FIG. 6, the first image 61 (reference image) shown in FIG. 6A has a horizontal pixel number × vertical pixel number of 640 × 480 pixels if the resolution is VGA. In FIG. 6, in order to simplify the description, 32 × 24 pixels are used. In the second image 62 to be subjected to motion detection shown in (b), the pixels are divided into a plurality of sub-blocks 62a (here, 4 × 3 sub-blocks as an example).

In this state, the correlation between each sub-block 62a in (b) and the area (a) corresponding to each sub-block 62a is obtained. Specifically, for each sub-block 62a shown in (b), the correlation coefficient for (a) is obtained, and the correlation coefficient (= Σ (m, n) [B (m, n) −C (m ', n')]) finds a pixel with a smaller value. Based on the correlation coefficient (m ′, n ′) of the pixel obtained in this way, the motion vector mv of the sub-block to which the pixel belongs is
mv = (m'-m, n'-n)
Is given. A summary of this is an image 63 in (c). As shown in (c), a motion vector mv is obtained for each 4 × 3 sub-block. By statistically processing the result, a final motion vector MV of one entire image is obtained. As an example of the statistical processing, there is a method of averaging after removing the maximum value and the minimum value. The motion vector MV (x, y) obtained in this way represents camera shake. In MV (x, y), the x component represents the horizontal camera shake, and the y component represents the vertical camera shake.

  Next, the operation of the image composition unit 7 in FIG. 1 will be described.

  FIG. 7 is a schematic diagram for explaining the image composition processing. In FIG. 7, (a) is a first image 71 serving as a reference. (B) is the second and subsequent images 72. (C) is an image in which motion compensation has been performed on the image 72, and the range of clipping the image 72 is shifted as shown in a region 73, and the correlation between the image 71 and the image 72 is increased to compensate for motion compensation. It is carried out. In (c), a region 73a is a cut-out area for the image 72, a region 73b is a region where no data exists, and the region 73 is composed of a region 73a and a region 73b.

  In the image composition process, when the image 71 shown in (a) is a, and the second and subsequent images 72 shown in (b) are b, the image Out after the composition is added by adding them based on the following formulas. Can be obtained.

Out (x, y) = a (x, y) + c (x, y)
However, in (c), a region 73b is a region where the corresponding c (x, y) does not exist. In this region 73b, instead of performing addition processing on the second and subsequent images 72, the data of the image 71 is stored. Is added to perform the addition process. In this way, by performing image composition processing on the motion-compensated image, it is possible to obtain a still image with camera shake correction. Note that the process of combining the third and subsequent images is the same as described above, and thus the description thereof is omitted.

  Next, an embodiment will be described in which the second and subsequent images to be combined are divided into a plurality of sub-blocks and image combining is performed.

  In FIG. 8, (a) is a first image as a reference, and a subject 81 and a background 82 are photographed in the image. (B) is the second and subsequent images to be combined. The positions of both the subject 81 and the background 82 are changed with respect to the first image in (a). (C) is an image obtained by extracting the subject 81 from (b) and performing motion correction. (D) is an image obtained by extracting the background 82 from (b) and performing motion compensation. (E) is an image obtained by synthesizing the image of (c) and the image of (d).

  In the image shown in FIG. 8A, the subject 81 and its surrounding image are divided into sub-blocks and the background 82 and its surrounding images are sub-blocked, and motion compensation is performed for each sub-block. Perform image composition processing. At the time of still image shooting, the background 82 originally does not move by itself. Therefore, when movement occurs as shown in FIG. On the other hand, since the subject 81 is often moving, when motion occurs as shown in (b), motion compensation is performed with a motion vector obtained by combining motion due to camera shake and motion of the subject itself. There is a need.

The subject 81 moves the subject 81 by changing the cut-out area from the region 83a to the region 83b based on the motion vector calculated by combining the motion due to the camera shake and the motion of the subject itself, as shown in (c). Compensation is performed. Further, the background 82 is subjected to motion compensation by changing the cut-out area from the region 83c to the region 83d as shown in (d) based on the motion vector calculated by the motion due to camera shake. Next, the image of the subject 81 subjected to motion compensation as shown in (c) and the image of the background 82 subjected to motion compensation as shown in (d) are combined as shown in (e).
In this way, by performing motion compensation by dividing an image into a plurality of blocks such as the background 82 and the subject 81, motion compensation with higher accuracy can be performed. Here, the example in which the image is divided into two blocks has been described, but it is also assumed that the image is divided into three or more blocks.

  Next, the operation of the thinning unit 11 in FIG. 1 will be briefly described.

  In FIG. 1, a moving image (so-called through image) is usually displayed on the display unit 13 of the camera device so that the movement of the subject can be observed before the shutter is pressed. From the time when the shutter is pressed until the recording of the still image to the information medium is completed, the still image immediately before the shutter is pressed on the display unit 13 to indicate to the user that the camera device is executing signal processing. Display the image. While the still image is displayed, the photographed still image is recorded on the information medium, and when the recording of the still image is completed, the recorded still image is reproduced and displayed on the display unit 13 for a certain period. After the display for a certain period is completed, the next still image can be captured, and the through image is displayed again on the display unit 13.

  However, in the present embodiment, as described above, the number of frames of the image data output from the camera unit 3 is large, and it is not necessary to display all the images on the display unit 13. While the still image recording process is performed as in the related art, an image immediately before the shutter is pressed can be displayed, and a moving image can be displayed during the still image recording process. In this case, since the number of frames is larger than usual, the moving image can be displayed normally by reducing the number of frames by the thinning unit 11 (for example, reducing to 30 frames per second). If the frame is not thinned and displayed while the number of frames is large, the processing capacity of the display unit 13 may be exceeded, and a problem may occur. It can be avoided. Note that the thinning unit 11 is not indispensable, and is not necessary when a moving image is not displayed during the still image recording process as described above.

  As described above, according to the present embodiment, still image shooting is performed by dividing a still image into a plurality of still images, and each of the divided still images is shot with a faster shutter speed. be able to. If the shutter speed can be set fast, the influence of camera shake can be reduced even when the subject is dark and the amount of light is insufficient, and image quality deterioration can be prevented. In addition, the fact that the influence of camera shake can be reduced can be expected to have the effect of reducing the size of the lens or making auxiliary light from the strobe unnecessary.

  The present invention relates to a camera device capable of shooting a still image, and is useful for a video camera, a digital still camera, a mobile phone with a camera, and the like.

1 is a block diagram showing a configuration of a camera device according to Embodiment 1 of the present invention. Timing chart showing operation of electronic shutter in embodiment 1 Schematic diagram showing the principle of motion compensation in the first embodiment Timing chart showing operation in the first embodiment Schematic diagram for explaining the principle of camera shake correction in the first embodiment Block diagram for explaining the principle of camera shake correction in the first embodiment Schematic diagram for explaining the operation of the motion compensation unit in the first embodiment. Schematic diagram for explaining the operation of the image composition unit in the first embodiment Schematic diagram for explaining an operation when performing image composition by dividing an area in the first embodiment Block diagram showing the configuration of a conventional camera device Schematic diagram for explaining the principle of camera shake generation in a conventional camera device Schematic diagram for explaining the principle of camera shake when the amount of light in a conventional camera device is sufficient Schematic diagram for explaining the principle of camera shake when the amount of light is insufficient in a conventional camera device Schematic diagram for explaining camera shake correction during movie shooting

Explanation of symbols

1 Lens 2 Image sensor (image sensor)
DESCRIPTION OF SYMBOLS 3 Camera part 4 Signal processing part 5 Frequency multiplier 6 Motion compensation part 7 Image composition part 8 Camera shake correction part 9 Still image signal processing 10 Information medium 11 Thinning part 12 Frame thinning part 13 Display part

Claims (5)

An image sensor that converts an optical image incident through a lens into an electrical signal;
A signal processing unit that generates a video signal based on an electrical signal output from the image sensor and outputs an operation clock of the image sensor;
A display unit capable of displaying a video signal output from the signal processing unit;
An information medium capable of recording or reproducing the video signal output from the signal processing unit,
A camera device capable of shooting at least a still image by operating a shutter button,
A frequency multiplying unit capable of multiplying the frequency of an operation clock output from the signal processing unit and input to the imaging device;
A camera shake detection unit capable of detecting camera shake of the camera device;
A motion compensation unit that shifts a frame of a still image output from the signal processing unit based on camera shake detected by the camera shake detection unit, and performs motion compensation of the image;
A plurality of images output from the motion compensation unit, and an image synthesis unit capable of generating a single still image,
When the amount of light in the subject is low,
The frequency multiplication unit multiplies the frequency of the operation clock so that the exposure time of the image sensor is shortened,
Operate the image sensor with a multiplied operation clock,
Based on the electrical signal output from the imaging device, the signal processing unit generates a plurality of images,
A camera device, wherein the plurality of images are combined by the image combining unit to generate one image.   The camera apparatus according to claim 1, wherein the camera shake detection unit includes an angular velocity sensor.   The camera apparatus according to claim 1, wherein the signal processing unit detects camera shake based on a frame correlation of the generated video signal.   4. The camera device according to claim 1, wherein the motion compensation unit divides an image output from the signal processing unit into a plurality of blocks, and performs control so as to perform motion compensation processing on each of the divided blocks. 5. . The camera device according to claim 4, wherein the image synthesis unit selectively performs image synthesis or non-synthesis processing on each of the blocks divided by the motion compensation unit.

Images