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The disclosure relates to techniques for calibration of an auto-focus process in an image capture device. The techniques may involve calibration of a lens actuator used to move a lens within a search range during an auto-focus process. For example, an image capture device may adjust reference positi

The disclosure relates to techniques for calibration of an auto-focus process in an image capture device. The techniques may involve calibration of a lens actuator used to move a lens within a search range during an auto-focus process. For example, an image capture device may adjust reference positions for the search range based on lens positions selected for different focus conditions. The different focus conditions may include a far focus condition and a near focus condition. The focus conditions may be determined based on a detected environment in which the device is used. Detection of an indoor environment may indicate a likelihood of near object focus, while detection of an outdoor environment may indicate a likelihood of far object focus. An image capture device may detect indoor and outdoor environments based on lighting, exposure, or other conditions.

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1. A method of calibrating an image capture device by storing an auto-focus lens position search range, the method comprising: providing a lens module of the image capture device, the lens module comprising a lens and a lens actuator;detecting a focus condition of an image capture device;moving the

1. A method of calibrating an image capture device by storing an auto-focus lens position search range, the method comprising: providing a lens module of the image capture device, the lens module comprising a lens and a lens actuator;detecting a focus condition of an image capture device;moving the lens among multiple lens positions;selecting one of the multiple lens positions when the focus condition is detected, based on a focus value, as a selected lens position;adjusting an auto-focus lens position search range based on the selected lens position;calibrating the search range according to the characteristics of the lens assembly; andstoring, in the image capture device, the adjusted auto-focus lens position search range. 2. The method of claim 1, wherein the focus condition is a first focus condition, the method further comprising: detecting a second focus condition of the image capture device; andadjusting the auto-focus lens position search range based on the selected lens position when the second focus condition is detected. 3. The method of claim 2, wherein the first focus condition is a focus condition associated with an indoor environment, and the second focus condition is a focus condition associated with an outdoor environment. 4. The method of claim 3, further comprising: adjusting a first bound of the auto-focus lens position search range when the first focus condition is detected; andadjusting a second bound of the auto-focus lens position search range when the second focus condition is detected,wherein the first bound corresponds to a near focus lens position and the second bound corresponds to a far focus lens position. 5. The method of claim 4, wherein moving the lens of the image capture device among multiple lens positions comprises: moving the lens among multiple lens positions between a near focus mechanical stop of the lens and the second bound when the first focus condition is detected; andmoving the lens among multiple lens positions between the first bound and a far focus mechanical stop of the lens when the second focus condition is detected. 6. The method of claim 5, further comprising: reducing the auto-focus lens position search range when the selected lens position is greater than the first bound or less than the second bound; andincreasing the auto-focus lens position search range when the selected lens position is greater than the second bound or less than the first bound. 7. The method of claim 1, further comprising determining a number of times the selected lens position has previously been selected; and adjusting the auto-focus lens position search range based on the number of times the selected lens position has previously been selected. 8. The method of claim 1, wherein the focus value includes a sharpness value of an image produced by the image capture device when the lens is at the selected position. 9. The method of claim 1, further comprising detecting the focus condition based on at least one of white balance data and exposure data of the image capture device. 10. The method of claim 1, further comprising detecting the focus condition based on recognition of one or more objects in an image produced by the image capture device. 11. The method of claim 1, further comprising storing the selected lens position as a drive value for a lens actuation module that moves the lens. 12. The method of claim 1, wherein the auto-focus lens position search range is bound by near focus and far focus bounds. 13. The method of claim 1, further comprising using the auto-focus lens position search range in a subsequent auto-focus process. 14. The method of claim 1, wherein the selected lens position corresponds to an optimal position to capture an image based on the focus value. 15. The method of claim 1, wherein the moving comprises moving the lens of the image capture device among multiple lens positions within the auto-focus lens position search range. 16. A non-transitory computer-readable storage medium comprising instructions that when executed cause one or more processors to: detect a focus condition of an image capture device;control movement of a lens of the image capture device among multiple lens positions;select one of the multiple lens positions when the focus condition is detected, based on a focus value, as a selected lens position;adjust an auto-focus lens position search range based on the selected lens position; andstore, in the image capture device, the adjusted auto-focus lens position search range. 17. The non-transitory computer-readable storage medium of claim 16, wherein the focus condition is a first focus condition, the instructions further comprising instructions to cause one or more processors to: detect a second focus condition of the image capture device; andadjust the auto-focus lens position search range based on the selected position when the second focus condition is detected. 18. The non-transitory computer-readable storage medium of claim 17, wherein the first focus condition is a focus condition associated with an indoor environment, and the second focus condition is a focus condition associated with an outdoor environment. 19. The non-transitory computer-readable storage medium of claim 18, wherein the instructions further comprising instructions to cause one or more processors to: adjust a first bound of the auto-focus lens position search range when the first focus condition is detected; andadjust a second bound of the auto-focus lens position search range when the second focus condition is detected,wherein the first bound corresponds to a near focus lens position and the second bound corresponds to a far focus lens position. 20. The non-transitory computer-readable storage medium of claim 19, the instructions further comprising instructions to cause one or more processors to: control movement of the lens among multiple lens positions between a near focus mechanical stop of the lens and the second bound when the first focus condition is detected; andcontrol movement of the lens among multiple lens positions between the first bound and a far focus mechanical stop of the lens when the second focus condition is detected. 21. The non-transitory computer-readable storage medium of claim 20, the instructions further comprising instructions to cause one or more processors to: reduce the auto-focus lens position search range when the selected lens position is greater than the first bound or less than the second bound; andincrease the auto-focus lens position search range when the selected lens position is greater than the second bound or less than the first bound. 22. The non-transitory computer-readable storage medium of claim 16, the instructions further comprising instructions to cause one or more processors to determine a number of times the selected lens position has previously been selected, and adjust the auto-focus lens position search range based on the number of times the selected lens position has previously been selected. 23. The non-transitory computer-readable storage medium of claim 16, wherein the focus value includes a sharpness value of an image produced by the image capture device when the lens is at the selected position. 24. The non-transitory computer-readable storage medium of claim 16, the instructions further comprising instructions to cause one or more processors to detect the focus condition based on at least one of white balance data and exposure data of the image capture device. 25. The non-transitory computer-readable storage medium of claim 16, the instructions further comprising instructions to cause one or more processors to detect the focus condition based on recognition of one or more objects in an image produced by the image capture device. 26. The non-transitory computer-readable storage medium of claim 16, the instructions further comprising instructions to cause one or more processors to store the selected lens position in memory as a drive value for a lens actuation module. 27. A method comprising: detecting a focus condition of an image capture device;moving a lens of the image capture device among multiple lens positions;selecting one of the lens positions based on a focus value as a selected lens position;storing the selected lens position as a drive value for a lens actuation module that moves the lens; andadjusting an auto-focus lens position search range based on the selected lens position when the focus condition is detected. 28. The method of claim 27, further comprising using the stored drive value to move the lens in an auto-focus process. 29. The method of claim 27, further comprising using the auto-focus lens position search range in a subsequent auto-focus process. 30. The method of claim 27, wherein the selected lens position corresponds to an optimal position to capture an image based on the focus value. 31. The method of claim 27, wherein the auto-focus lens position search range is bound by near focus and far focus bounds. 32. The method of claim 27, wherein the moving comprises moving the lens of the image capture device among multiple lens positions within the auto-focus lens position search range. 33. The method of claim 27, wherein the image capture device comprises a mobile phone, and wherein the method is performed in the mobile phone. 34. A method comprising: detecting a first focus condition of an image capture device;detecting a second focus condition of the image capture device;moving a lens of the image capture device among multiple lens positions;selecting one of the lens positions based on a focus value as a selected lens position;adjusting an auto-focus lens position search range based on an auto-focus calibration process, wherein a near focus bound of the search range is adjusted when the first focus condition is detected and a far focus bound of the search range is adjusted when the second focus condition is detected;adjusting the auto-focus lens position search range based on the selected lens position when the first focus condition is detected; andadjusting the auto-focus lens position search range based on the selected lens position when the second focus condition is detected,wherein the first focus condition is a focus condition associated with an indoor environment, and the second focus condition is a focus condition associated with an outdoor environment. 35. The method of claim 34, further comprising using the auto-focus lens position search range in a subsequent auto-focus process. 36. The method of claim 34, wherein the image capture device comprises a video camera. 37. The method of claim 34, wherein the image capture device comprises a mobile computing device, and wherein the method is performed in the mobile computing device.