Anti-Shake Method for Camera and Camera

• US 20190320118A1
• Filed: 11/30/2017
• Published: 10/17/2019
• Est. Priority Date: 12/02/2016
• Status: Active Grant

• Current Assignee: Hangzhou Hikvision Digital Technology Company Limited
• Original Assignee: Hangzhou Hikvision Digital Technology Company Limited
• Inventors: Ma, Weimin, Shen, Chenyi, Wang, Huan, You, Can
• Granted Patent: US 10,805,539 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing
• CPC Class Codes: G08B 13/19606 Discriminating between target movement or movement in an area of interest and other non-signicative movements, e.g. target movements induced by camera shake or movements of pets, falling leaves, rotating fan
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors
• CPC Class Codes: H04N 23/6815 by distinguishing pan or tilt from motion
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast
• CPC Class Codes: H04N 7/183 for receiving images from a single remote source

Abstract

Provided in an embodiment of the present application are an anti-shake method for a camera and a camera. The method comprises: obtaining current shake data of a camera, wherein the shake data comprises position change data of the camera when the camera shakes, and the shake data is detected by a shake detector; determining, according to a preset relationship between position change of an anti-shake lens for shake compensation and shake data, movement data of the anti-shake lens; and adjusting a position of the anti-shake lens according to the movement data, so that an image sensor captures a shake-compensated image. By applying the embodiment of the present application, anti-shake processing can be performed for the higher or lower frequency shake, improving anti-shake performance.

Claims

1. An anti-shake method for a camera, wherein the camera comprises a lens, a shake detector and an image sensor, the lens comprising a movable anti-shake lens;

the method comprises;

acquiring current shake data of the camera by the shake detector, wherein the shake data comprises position change data of the camera when the camera shakes;

determining position change data of the anti-shake lens based on the current shake data of the camera and a preset relationship between position change of the anti-shake lens for shake compensation and shake data; and

adjusting a position of the anti-shake lens based on the position change data of the anti-shake lens, so as to cause the image sensor to capture a shake-compensated image.

2. The method of claim 1, wherein acquiring current shake data of the camera by the shake detector comprises:

for each of preset periods, acquiring shake data of the camera in this preset period by the shake detector, wherein the shake data comprises an angle variation of the camera in a current period relative to a previous period;

before determining position change data of the anti-shake lens based on the current shake data of the camera and a preset relationship between position change of the anti-shake lens for shake compensation and shake data, the method further comprises;

determining whether the camera shakes continuously in a preset number of periods based on shake data of the camera in the preset number of periods, a preset shake threshold and a preset standstill threshold, and if the camera shakes continuously in the preset number of periods, enabling an anti-shake function; and

the step of determining position change data of the anti-shake lens based on the current shake data of the camera and a preset relationship between position change of the anti-shake lens for shake compensation and shake data, comprises;

if the anti-shake function is enabled, determining the position change data of the anti-shake lens based on the current shake data of the camera and the preset relationship between position change of the anti-shake lens for shake compensation and shake data.

3. The method of claim 2, wherein the step of determining whether the camera shakes continuously in a preset number of periods based on shake data of the camera in the preset number of periods, a preset shake threshold and a preset standstill threshold, and if the camera shakes continuously in the preset number of periods, enabling an anti-shake function, comprises:

determining a first camera state of the camera in a previous period of the current period, wherein the camera state comprises a standstill state or a shake state; and

when the first camera state is the standstill state,

determining whether the camera shakes in the current period, based on the preset shake threshold and the angle variation contained in the shake data of the camera in the current period; and

determining whether the camera shakes continuously in the preset number of periods;

if the camera shakes continuously in the preset number of periods, determining that a second camera state of the camera in the current period is the shake state, and enabling the anti-shake function;

if the camera does not shake continuously in the preset number of periods, determining that the second camera state of the camera in the current period is the standstill state; and

when the first camera state is the shake state,

determining and recording whether the camera is standstill in the current period based on the preset standstill threshold and the angle variation contained in the shake data of the camera in the current period; and

determining whether the camera is standstill continuously in the preset number of periods;

if the camera is standstill continuously in the preset number of periods, determining that the second camera state of the camera in the current period is the standstill state, and disabling the anti-shake function;

if the camera is not standstill continuously in the preset number of periods, determining that the second camera state of the camera in the current period is the shake state.

4. The method of claim 3, wherein the step of determining whether the camera shakes in the current period, based on the preset shake threshold and the angle variation contained in the shake data of the camera in the current period, comprises:

determining whether the angle variation contained in the shake data of the camera in the current period is greater than the preset shake threshold;

if the angle variation is greater than the preset shake threshold, determining that the camera shakes in the current period, and recording the number of times that the camera shakes;

if the angle variation is not greater than the preset shake threshold, determining that the camera does not shake, and resetting the number of times that the camera shakes;

the step of determining and recording whether the camera is standstill in the current period based on the preset standstill threshold and the angle variation contained in the shake data of the camera in the current period, comprises;

determining whether the angle variation contained in the shake data of the camera in the current period is less than the preset standstill threshold;

if the angle variation is less than the preset standstill threshold, determining that the camera is standstill in the current period, and recording the number of times that the camera is standstill;

if the angle variation is not less than the preset standstill threshold, determining that the camera is not standstill in the current period, and resetting the number of times that the camera is standstill.

5. The method of claim 2, wherein the preset relationship between shake data and position change of the anti-shake lens for shake compensation, comprises:

a correspondence between the angle variation of the camera and a compensation vector of the anti-shake lens under a preset focal length;

the step of determining position change data of the anti-shake lens based on the current shake data of the camera and a preset relationship between position change of the anti-shake lens for shake compensation and shake data, comprises;

determining a direction of position change and a distance of position change of the anti-shake lens, based on the correspondence between the angle variation of the camera and the compensation vector of the anti-shake lens under the preset focal length;

the step of adjusting a position of the anti-shake lens based on the position change data of the anti-shake lens, so as to cause the image sensor to capture a shake-compensated image, comprises;

adjusting the position of the anti-shake lens based on the determined direction of position change and the determined distance of position change of the anti-shake lens, so as to cause the image sensor to capture the shake-compensated image.

6. The method of claim 2, wherein the shake detector is a gyroscope;

the step of acquiring current shake data of the camera by the shake detector, comprises;

receiving current angular velocity data sent by the gyroscope; and

calculating the angle variation of the camera in the current period relative to the previous period, based on the length of the preset period, the current angular velocity data, and angular velocity data received in the previous period.

7. The method of claim 2, wherein the method further comprises:

receiving one or more of an operation instruction for enabling the anti-shake function, an operation instruction for disabling the anti-shake function, and an instruction for setting an anti-shake level, which are sent by a user;

if the operation instruction for enabling the anti-shake function is received from the user, enabling the anti-shake function;

if the operation instruction for disabling the anti-shake function is received form the user, disabling the anti-shake function; and

if the instruction for setting an anti-shake level is received from the user, reading and saving an anti-shake level carried in the instruction for setting an anti-shake level, wherein the anti-shake level comprises;

the shake threshold and/or the standstill threshold.

8. A camera, comprising:

a lens, a shake detector, an image sensor and a first processor, wherein the lens comprises a movable anti-shake lens;

the lens is configured for optical framing;

the shake detector is configured for detecting current shake data of the camera;

the image sensor is configured for capturing an image;

the first processor is configured for acquiring current shake data of the camera by the shake detector, wherein the shake data comprises position change data of the camera when the camera shakes;

determining position change data of the anti-shake lens based on the current shake data of the camera and a preset relationship between position change of the anti-shake lens for shake compensation and shake data; and

adjusting a position of the anti-shake lens based on the position change data of the anti-shake lens, so as to cause the image sensor to capture a shake-compensated image.

9. The camera of claim 8, wherein,

the shake detector is configured for:

for each of preset periods, acquiring the shake data of the camera in this preset period;

the position change data of the camera is an angle variation of the camera in a current period relative to a previous period;

the first processor is configured for;

determining whether the camera shakes continuously in a preset number of periods based on shake data of the camera in the preset number of periods, a preset shake threshold and a preset standstill threshold, and if the camera shakes continuously in the preset number of periods, enabling an anti-shake function;

if the anti-shake function is enabled, determining the position change data of the anti-shake lens based on the current shake data of the camera and the preset relationship between position change of the anti-shake lens for shake compensation and shake data.

10. The camera of claim 9, further comprising a second processor configured for receiving one or more of an operation instruction for enabling the anti-shake function, an operation instruction for disabling the anti-shake function, and an instruction for setting an anti-shake level, which are sent by a user;

if the operation instruction for enabling the anti-shake function is received from the user, enabling the anti-shake function;

if the operation instruction for disabling the anti-shake function is received form the user, disabling the anti-shake function; and

if the instruction for setting an anti-shake level is received from the user, reading and saving an anti-shake level carried in the instruction for setting an anti-shake level, wherein the anti-shake level comprises;

the shake threshold and/or the standstill threshold.

11. A surveillance camera, comprising:

a shake detector, a system on chip, a lens, a motor driver, and a photosensitive sensor, wherein the lens comprises a movable optical lens;

the shake detector is electrically connected to the system on chip, and sends a shake signal to the system on chip;

the system on chip is electrically connected to the shake detector, the motor driver and the photosensitive sensor, respectively, and receives the shake signal sent by the shake detector, and sends a control signal to the motor driver and the photosensitive sensor based on the shake signal;

the motor driver is connected to the system on chip and the optical lens, and receives the control signal sent by the system on chip to drive the optical lens to move; and

the photosensitive sensor is located in rear of the lens, and receives the control signal sent by the system on chip and captures light passing through the lens to form a shake-compensated image.

12. The surveillance camera of claim 11, wherein, the lens further comprises:

a photosensitive lens, wherein,

a set of photosensitive lenses is located in front of the optical lens; and

the photosensitive sensor is located in rear of the optical lens.

13. The surveillance camera of claim 12, wherein the photosensitive lens comprises:

a magnifying lens and a focusing lens;

wherein,

the focusing lens is located in rear of the magnifying lens and in front of the optical anti-shake compensation lens.

14. The surveillance camera of claim 13, wherein the magnifying lens comprises at least two magnifying lenses.

15. The surveillance camera of claim 13, wherein the focusing lens comprises at least two focusing lenses.

16. The surveillance camera of claim 12, wherein,

the motor driver comprises:

a motor driving chip and an optical compensation motor;

wherein,

the motor driving chip is electrically connected to the system on chip and the optical compensation motor, respectively; and

the optical compensation motor is connected to the optical lens to drive the optical lens to move.

17. The surveillance camera of claim 11, wherein,

the shake detector is a gyroscope.

18. The surveillance camera of claim 11, wherein,

the surveillance camera comprises at least two optical lenses;

and

the number of the photosensitive sensors is equal to the number of the optical lenses.