Dual aperture zoom camera with video support and switching / non-switching dynamic control
A dual-aperture zoom digital camera operable in both still and video modes. The camera includes Wide and Tele imaging sections with respective lens/sensor combinations and image signal processors and a camera controller operatively coupled to the Wide and Tele imaging sections. The Wide and Tele imaging sections provide respective image data. The controller is configured to output, in a zoom-in operation between a lower zoom factor (ZF) value and a higher ZF value, a zoom video output image that includes only Wide image data or only Tele image data, depending on whether a no-switching criterion is fulfilled or not.
1. A zoom digital camera, comprising:
a first imaging section that includes a first fixed effective focal length (EFL 1 ) lens with a first field of view (FOV 1 ) and a first sensor, the first imaging section operative to provide first image data of an object or scene;
a second imaging section that includes a second fixed effective focal length (EFL 2 ) lens with a second field of view (FOV 2 ) that is narrower than FOV 1 and a second sensor, the second imaging section operative to provide second image data of the object or scene; and
a camera controller operatively coupled to the first and second imaging sections and configured to evaluate if a no-switching criterion is fulfilled or not fulfilled, wherein if the no-switching criterion is fulfilled in a zoom-in operation between a lower zoom factor (ZF) value and a higher ZF value at a zoom factor (ZF) higher than an up-transfer ZF, the camera controller is further configured to output a zoom video output image that includes only first image data, wherein if the no-switching criterion is not fulfilled, the camera controller is further configured to output a zoom video output image that includes only transformed, digitally zoomed second image data, and wherein EFL 2 >1.5×EFL 1 .
2. The zoom digital camera of claim 1 , wherein EFL 2 ≥2×EF 1 .
3. The zoom digital camera of claim 1 , wherein EFL 1 <4 mm and EFL 2 >4 mm.
4. The zoom digital camera of claim 1 , wherein the no-switching criterion includes a shift between the first and second image data calculated by global registration, the shift being greater than a first threshold.
5. The zoom digital camera of claim 1 , wherein the no-switching criterion includes a disparity range calculated by global registration, the disparity range being greater than a second threshold.
6. The zoom digital camera of claim 1 , wherein the no-switching criterion includes an effective resolution of the second image data being lower than an effective resolution of the first image data.
7. The zoom digital camera of claim 1 , wherein the no-switching criterion includes a number of corresponding features in the first and second image data being smaller than a third threshold.
8. The zoom digital camera of claim 1 , wherein the no-switching criterion includes a majority of objects imaged in an overlap area of the first and second image data being calculated to be closer to the camera than a first threshold distance.
9. The zoom digital camera of claim 1 , wherein the no-switching criterion includes some objects imaged in an overlap area of the first and second image data being calculated to be closer than a second threshold distance while other objects imaged in the overlap area of the first and second image data being calculated to be farther than a third distance threshold.
10. The zoom digital camera of claim 1 , wherein the camera controller includes a user control module for receiving user inputs and a sensor control module for configuring each sensor to acquire the first and second image data based on the user inputs, and wherein the user inputs include a zoom factor, a camera mode and a region of interest.
11. The zoom digital camera of claim 1 , wherein the camera controller is further configured to combine in still mode, at a predefined range of ZF values, at least some of the first and second image data to provide a fused output image of the object or scene from a particular point of view.
12. A method for obtaining zoom images of an object or scene using a digital camera, comprising:
providing in the digital camera a first imaging section having a first fixed effective focal length (EFL 1 ) lens with a first field of view (FOV 1 ) and a first image sensor, a second imaging section having a second fixed effective focal length (EFL 2 ) lens with a second field of view (FOV 2 ) that is narrower than FOV 1 and a second image sensor, and a camera controller operatively coupled to the first and second imaging sections, wherein EFL 2 >1.5×EFL 1 ; and
configuring the camera controller to evaluate if a no-switching criterion is fulfilled or not fulfilled, and, if the no-switching criterion is fulfilled, configuring the camera controller to output at a zoom factor (ZF) higher than an up-transfer ZF a zoom video output image that includes only first image data in a zoom-in operation between a lower ZF value and a higher ZF value, or if the no-switching criterion is not fulfilled, configuring the camera controller to output a zoom video output image that includes only transformed, digitally zoomed second image data.
13. The method of claim 12 , wherein EFL 2 ≥2×EFL 1 .
14. The method of claim 12 , wherein EFL 1 21 4 mm and EFL 2 >4 mm.
15. The method of claim 12 , wherein the no-switching criterion includes a shift between the first and second image data calculated by global registration, the shift being greater than a first threshold.
16. The method of claim 12 , wherein the no-switching criterion includes a disparity range calculated by global registration, the disparity range being greater than a second threshold.
17. The method of claim 12 , wherein the no-switching criterion includes a majority of objects imaged in an overlap area of the first and second image data being calculated to be closer to the camera than a first threshold distance.
18. The method of claim 12 , wherein the no-switching criterion includes some objects imaged in an overlap area of the first and second image data being calculated to be closer than a second threshold distance while other objects imaged in the overlap area of the first and second image data being calculated to be farther than a third threshold distance.