JPH06350895A - Method for correcting jiggle in video camera - Google Patents

Abstract

PURPOSE:To calculate the movement vector of a screen peripheral part so as to detect and correct jiggle. CONSTITUTION:A data pickup part 1 taking out image data at a prescribed position at every frame of respective images, a movement detecting part 2 detecting the movement vector of a part (the prescribed position) in a photographing screen, a movement storage part 3 storing the movement vector in order, an arithmetic part 4 obtaining the movement vector of a camera, a discriminating part 5 discriminating the kinds of the movement of the camera, that is, whether jiggle or panning, etc., an image storage part 6 which stores photographed image data of an area being larger than the display screen supplied from an image-picking-up part (abbrieviated) of CCD, etc., and reads image data of the designated area so as to output image data 8 jiggle-corrected after prescribed time elasps and a control part 7 controlling the respective parts, for example, controlling the reading of the image storage part 6 in accordance with the movement of the camera, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera-shake correction method for a video camera, which suppresses deterioration of a captured image due to camera shake.

[0002]

2. Description of the Related Art A conventional camera-shake correction method for a video camera detects a motion vector of the camera by performing a necessary calculation on photographed image data in a time axis direction, and as shown in FIG. When a camera shake (camera movement) represented by the upper left vector 40 occurs, the stored data is read out centering on the lower right part of the camera angle 41 so as to cancel the upper left vector 40 and displayed. The screen (frame) 42 is output. Also,
(B) When the camera shake indicated by the lower right vector 43 in the figure occurs, the display screen (frame) is output centering on the upper left part of the camera angle so as to cancel the lower right vector 43. However, when determining the movement of the camera, the movement of the captured image is erroneously detected and the camera shake is corrected based on the error. When panning is performed in the horizontal direction, the camera shake is corrected for the movement. Was happening. For example, in the panning error correction, the camera shake correction is activated for each predetermined amount of movement of the camera angle, and the movement of the display screen does not match the panning movement, resulting in a sense of discomfort. There was a problem of deterioration.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a camera shake correction method for a video camera, which determines the type of camera movement and performs camera shake correction based on the judgment. To do.

[0004]

In order to achieve the above object, a data extraction unit for extracting image data at a predetermined position of a photographing screen (camera angle) in a time axis direction, and an image data at a corresponding position extracted. A motion detection unit that performs a necessary calculation to detect a motion vector of a portion (each position) on a shooting screen, a motion storage unit that stores the obtained motion vector of each position, and a motion vector that is stored in the motion vector. And a determination unit that determines the type of camera movement based on the movement of the camera, store captured image data, and display image data according to the type of movement of the camera. And an image storage unit for reading out the data and a control unit for controlling the image storage unit and controlling each unit.

[0005]

With the above configuration, the motion vector of each part of the peripheral portion of the photographing screen (camera angle) is subjected to a majority calculation to obtain the motion vector of the camera. When the camera motion is almost one type of motion vector within a predetermined time, in other words, when there is no change (smallness) between the motion vectors at each time, the determination unit determines that the type of camera motion is panning. The camera shake correction of the shooting screen (camera angle) is not performed, or the camera shake correction is limited to the peripheral portion of the screen according to the magnitude of the motion vector of the camera. If the motion vector of the camera vibrates within a predetermined time, the determination unit determines that the type of camera motion is camera shake, and corrects the camera shake based on the direction and size of canceling the camera motion vector. Carry out.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for correcting camera shake of a video camera according to the present invention will be described in detail below with reference to the drawings. Figure 1
FIG. 3 is a block diagram of an embodiment of a video camera shake correction method according to the present invention. Reference numeral 1 denotes a data extraction unit that extracts image data at a predetermined position of captured image data in an area larger than the display screen supplied from an image pickup unit (omitted) such as a CCD for each frame of each image. Reference numeral 2 denotes a motion detection unit that detects a motion vector of a portion (predetermined position) of the shooting screen by performing a required calculation in the time axis direction using the extracted image data. Reference numeral 3 denotes a motion storage unit that sequentially stores motion vectors obtained within a predetermined time. Reference numeral 4 is a calculation unit that majority-calculates the motion vector of each part of the corresponding frame to obtain the motion vector of the camera. Reference numeral 5 denotes a determination unit that determines the type of motion, such as camera shake or panning, based on changes in the motion vector of the camera in the time direction. Reference numeral 6 is an image which stores photographed image data of an area larger than the display screen, which is supplied from an image pickup unit (omitted) such as CCD, and after a predetermined time, reads out image data of a designated area and outputs image data 8 after image stabilization. It is a storage unit. Reference numeral 7 denotes a control unit that controls each unit such as controlling reading of the image storage unit 6 according to the movement of the camera.

The operation of the image stabilization method of the video camera according to the present invention will be described. FIG. 2 is a diagram showing the motion vector of each part for detecting the motion vector of the camera by the image stabilization method of the video camera according to the present invention. A, B,
Compared to the central portion E, the four corners of the screens C and D are positions where the background and the like are photographed, and there are few moving subjects. Therefore, each motion vector generated from the data of the four corner positions of A, B, C, and D represents the motion of the camera part. For example, the motion vector 2 of the camera part
0 is a vector having a predetermined magnitude in the right horizontal direction, and the motion vector of each of A, B, and D is equal to the motion vector 20, but the motion vector of the C portion has a predetermined magnitude in the upper right direction. Is a vector. Also in this case,
The motion vector of the camera is determined as the motion vector 20 of the part by the majority operation of the motion vectors of the parts A, B, C and D.

FIG. 3 is a principle diagram for detecting the type of camera movement in the image stabilization method of the video camera according to the present invention. When the motion vector 30 of the camera is displayed at a predetermined time interval, it becomes a substantially constant vector.
It is the panning of the camera. Camera motion vector 30
The state of (b) in which the size and the direction change is that the camera is vibrating, and it is determined to be camera shake. When the discrimination unit 5 detects camera shake, the camera motion vector 3
When the direction of the motion vector is the upper left and the size is a predetermined size, the corresponding output data of the image storage unit 6 is set to the lower right direction with respect to the range of the standard output screen so as to cancel 0. It is read so as to shift the movement amount of. In the case of camera panning, the output data of the image storage unit 6 is output as it is in the standard output screen range. If the image at the center of the camera angle is a moving image,
The camera shake correction may be performed only on the peripheral portion including the A, B, C, and D4 corner positions.

[0009]

As described above, the present invention provides a camera-shake correction method for a video camera, which determines the type of camera movement and performs camera-shake correction based on the determination. Therefore, it is possible to prevent the camera angle from shaking due to camera shake, and to suppress the abnormal movement of the camera angle (display screen) during panning, which is seen in a video camera with a conventional camera shake correction method, and it is expected to improve the image quality.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a video camera shake correction method according to the present invention.

FIG. 2 is a diagram showing a motion vector of each unit for detecting a motion vector of the camera by the image stabilization method of the video camera according to the present invention.

FIG. 3 is a principle diagram for detecting the type of camera movement by the image stabilization method of the video camera according to the present invention.

FIG. 4 is a conceptual diagram illustrating a method of generating an output image in camera shake correction.

[Explanation of symbols]

 1 Data Extraction Section 2 Motion Detection Section 3 Motion Storage Section 4 Calculation Section 5 Discrimination Section 6 Image Storage Section 7 Control Section 8 Shake-corrected Image Data 20 Motion Vector of Part 30 Camera Motion Vector 40 Upper Left Vector 41 Camera Angle 42 Display screen (frame) 43 Right downward vector

Claims (6)

[Claims] 1. A data extraction unit for extracting image data at a predetermined position of a photographing screen (camera angle) in a time axis direction,
A motion detection unit that performs a necessary calculation on the extracted image data of the corresponding position to detect a motion vector of a portion (each position) on the photographing screen, and a motion storage unit that stores the obtained motion vector of each position. An operation unit for performing a required operation on the stored motion vector to obtain a camera motion, a determination unit for determining a type of the camera motion based on the camera motion, and a camera unit for storing captured image data The image stabilization method for a video camera, comprising: an image storage unit for reading out display image data according to the type of movement of the image storage unit; and a control unit for controlling the image storage unit and controlling each unit. 2. The image stabilization method for a video camera according to claim 1, further comprising a data extraction unit that extracts image data from positions of at least four corners of the peripheral edge of the shooting screen. 3. The image stabilization method for a video camera according to claim 1, wherein the image stabilization processing for correcting the motion vector is performed on the peripheral edge image data including at least the four corner positions of the display screen. 4. The calculation unit obtains the motion of the camera by performing a majority calculation on the motion vector at each position.
Image stabilization method for the described video camera. 5. The image stabilization method for a video camera according to claim 1, wherein the determination unit determines that the motion vector of the camera is vibrating and determines that the image is a camera shake. 6. The image stabilization method for a video camera according to claim 1, wherein the discriminating unit determines a panning operation when the motion vector of the camera is smaller than a predetermined change amount.