Dual aperture zoom digital camera
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 combine in still mode at least some of the Wide and Tele image data to provide a fused output image from a particular point of view, and to provide without fusion continuous zoom video mode output images, each output image having a given output resolution, wherein the video mode output images are provided with a smooth transition when switching between a lower zoom factor (ZF) value and a higher ZF value or vice versa, and wherein at the lower ZF the output resolution is determined by the Wide sensor while at the higher ZF value the output resolution is determined by the Tele sensor.
1. A multi-camera, comprising:
a Wide camera that includes a fixed focal length Wide lens with a Wide field of view (FOV W ) and a Wide sensor, the Wide camera operative to provide a video stream of Wide input images of an object or scene;
a Tele camera that includes a fixed focal length Tele lens with a Tele field of view (FOV T ) that is narrower than FOV W and a Tele sensor, the Tele camera operative to provide a video stream of Tele input images of the object or scene; and
a camera controller operatively coupled to the Wide and Tele cameras, the camera controller configured to provide a zoom video stream of output images of the object or scene with a smooth transition when switching between a lower zoom factor (ZF) value and a higher ZF value or vice versa, each output image having a respective output resolution,
wherein at the lower ZF value the output resolution is determined by the Wide sensor that provides the output images, wherein at the higher ZF value the output resolution is determined by the Tele sensor that provides the output images,
and wherein at the higher ZF value the Wide sensor is operating in a lower frame rate than the Tele sensor.
2. The multi-camera of claim 1 , wherein the smooth transition is performed to reduce a position shift that is dependent on a distance to the object in a certain region of interest (ROI) when switching from the Wide camera to the Tele camera or vice versa in the zoom video stream of output images.
3. The multi-camera of claim 2 , wherein the camera controller includes a user control module for receiving user inputs and a sensor control module for configuring each of the Wide and Tele sensors to acquire the respective input images based on the user inputs.
4. The multi-camera of claim 3 , wherein the user inputs include a zoom factor, a camera mode and the ROI.
5. The multi-camera of claim 3 , wherein the sensor control module has a setting that depends on FOV W , FOV T and on a sensor oversampling ratio, the setting used in the configuration of each sensor.
6. The multi-camera of claim 5 , wherein the Wide and Tele FOVs and the sensor oversampling ratio satisfy the condition 0.8*PL Wide /PL video <Tan (FOV Wide )/Tan (FOV Tele )<1.2*PL Wide /PL video , wherein PL Wide is an in-line number of Wide sensor pixels and wherein PL video is an in-line number of output video format pixels.
7. The multi-camera of claim 1 , wherein the multi-camera provides focus by focusing the Wide camera and/or the Tele camera to an autofocus position, wherein the smooth transition includes a calculation of the position shift using a transformation coefficient based on the autofocus position produced within a time period before the switching from the Wide camera to the Tele camera or vice versa.
8. The multi-camera of claim 1 , wherein the smooth transition includes a calculation of the position shift using as inputs pixel data from both a Wide input image and a Tele input image from respective video streams of the Wide and Tele input images, wherein the pixel data is obtained from respective input images produced within a time period before the switching from the Wide camera to the Tele camera or vice versa.
9. The multi-camera of claim 1 , wherein the Tele lens includes a ratio of total length (TTL)/effective focal length (EFL) smaller than 1.
10. The multi-camera of claim 9 , wherein each of the Wide and Tele lenses includes five lens elements.
11. The multi-camera of claim 10 , wherein the five elements have, in order from the object side, positive-negative-negative-positive-negative powers.
12. The multi-camera of claim 10 , wherein the five elements have, in order from the object side, positive-negative-positive-negative and positive or negative powers.
13. The multi-camera of claim 1 , wherein the camera controller configuration to provide the zoom video stream of output images with a smooth transition when switching between a lower ZF value and a higher ZF value or vice versa includes a configuration that uses information either from the Wide sensor or from the Tele sensor.
14. The multi-camera of claim 1 , wherein the camera controller configuration to provide the zoom video stream of output images with a smooth transition when switching between a lower ZF value and a higher ZF value or vice versa includes a configuration that uses a high ZF secondary information from the Wide camera.
15. The multi-camera of claim 1 , wherein the camera controller configuration to provide the zoom video stream of output images with a smooth transition when switching between a lower ZF value and a higher ZF value or vice versa includes a configuration that uses at high ZF secondary information from the Wide camera and uses a low ZF secondary information from the Tele camera.
16. The multi-camera of claim 1 , wherein the camera controller is configured to reduce an image jump effect seen in the zoom video stream of output images, and wherein the camera controller is further configured, when switching from an output of the Tele camera to an output of the Wide camera or vice versa, to reduce the image jump effect seen in video output images by matching scale between the Wide and Tele images.
17. The multi-camera of claim 1 , wherein the camera controller is configured to reduce an image jump effect seen in the zoom video stream of output images, and wherein the camera controller is further configured, when switching from an output of the Tele camera to an output of the Wide camera or vice versa, to reduce the image jump effect seen in video output images by matching brightness between the Wide and Tele images.
18. The multi-camera of claim 1 , wherein the camera controller is configured to reduce an image jump effect seen in the zoom video stream of output images, wherein the camera controller is further configured, when switching from an output of the Tele camera to an output of the Wide camera or vice versa, to reduce the image jump effect seen in video output images by matching color between the Wide and Tele images.
19. The multi-camera of claim 1 , wherein the camera controller is configured to reduce discontinuities seen in the zoom video stream of output images, wherein the camera controller is further configured, when switching from an output of the Tele camera to an output of the Wide camera or vice versa, to reduce the image jump effect seen in video output images by matching color between the Wide and Tele images.
20. The multi-camera of claim 1 , wherein the camera controller is configured to fuse a Wide input image and a Tele input image to create a fused output image.
21. The multi-camera of claim 1 , wherein the Wide and Tele image sensors have identical pixel counts.
22. The multi-camera of claim 21 , wherein the pixel count is 12 MP.
23. A mobile device comprising the multi-camera of claim 1 .
24. The mobile device of claim 23 , wherein the mobile device is a smartphone.