Methods and apparatus for use with multiple optical chains
Methods and apparatus for supporting zoom operations using a plurality of optical chain modules, e.g., camera modules, are described. Switching between use of groups of optical chains with different focal lengths is used to support zoom operations. Digital zoom is used in some cases to support zoom levels corresponding to levels between the zoom levels of different optical chain groups or discrete focal lengths to which optical chains may be switched. In some embodiments optical chains have adjustable focal lengths and are switched between different focal lengths. In other embodiments optical chains have fixed focal lengths with different optical chain groups corresponding to different fixed focal lengths. Composite images are generate from images captured by multiple optical chains of the same group and/or different groups. Composite image is in accordance with a user zoom control setting. Individual composite images may be generated and/or a video sequence.
1. A method which involves use of multiple optical chains of a camera device, said multiple optical chains including at least a first group of optical chains and a second group of optical chains, the method comprising:
capturing images using both said first group of optical chains and said second group of optical chains during a first time period during which focal lengths of optical chains in said first and second groups of optical chains remain fixed;
changing a focal length of optical chains in said first group of optical chains from a first focal length to a second focal length during a second time period;
capturing images using said second group of optical chains during said second time period, optical chains in said second group of optical chains having a focal length which remains unchanged during said second time period while the focal length of optical chains in said first group is changed;
generating a first composite image from multiple images captured during said first time period; and
generating a second composite image from images captured during said second time period by said second group of optical chains.
2. The method of claim 1 ,
wherein generating the first composite image from multiple images captured during said first time period includes using at least: i) an image captured by an optical chain in the first group of optical chains and ii) an image captured by an optical chain in the second group of optical chains, to generate the first composite image; and
wherein generating the second composite image from images captured during said second time period includes generating an image from images captured by multiple different optical chains in the second group during the second time period.
3. The method of claim 2 , wherein generating the second composite image from images captured during said second time period is performed without using image data from an optical chain in the first group of optical chains.
4. The method of claim 2 , further comprising:
changing the focal length of optical chains in said second group of optical chains during a third time period; and
capturing images using said first group of optical chains during the third time period, the focal length of optical chains in said first group of optical chains remaining unchanged during said third time period during which the focal length of optical chains in said second group of optical chains is changed.
5. The method of claim 4 , further comprising
generating a third composite image from images captured during said third time period by said first group of optical chains.
6. The method of claim 5 ,
wherein the first and second groups have the same focal length during the first period of time, said same focal length during the first period of time being the first focal length; and
wherein the first and second groups have the same focal length during a fourth period of time, said same focal length during the fourth period of time being said second focal length, said second focal length being larger than said first focal length.
7. The method of claim 6 ,
wherein said second period of time immediately follows said first period of time;
wherein said third period of time immediately follows said second period of time; and
wherein said fourth period of time immediately follows said third period of time.
8. The method of claim 1 , wherein said second period of time immediately follows said first period of time.
9. The method of claim 1 ,
wherein said multiple optical chains, including said first group of optical chains and said second group of optical chains, are included in a handheld camera; and
wherein said first group of optical chains and said second group of optical chains each include multiple optical chains with adjustable focal lengths.
10. A camera device comprising:
multiple optical chains, said multiple optical chains including at least a first group of optical chains and a second group of optical chains; and
a processor configured to control the camera device to:
capture images using both said first group of optical chains and said second group of optical chains during a first time period during which focal lengths of optical chains in said first and second groups of optical chains remain fixed;
generate a first composite image from multiple images captured during said first time period;
change a focal length of optical chains in said first group of optical chains from a first focal length to a second focal length during a second time period;
capture images using said second group of optical chains during said second time period, optical chains in said second group of optical chains having a focal length which remains unchanged during said second time period while the focal length of optical chains in said first group is changed; and
generate a second composite image from images captured during said second time period by said second group of optical chains.
11. The camera device of claim 10 ,
wherein the camera device is a handheld camera device.
12. The camera device of claim 11 ,
wherein said first group of optical chains and said second group of optical chains each include multiple optical chains with adjustable focal lengths.
13. The camera device of claim 10 ,
wherein said first group of optical chains and said second group of optical chains each include multiple optical chains with adjustable focal lengths.