GPS pre-acquisition for geotagging digital photos

摘要

A handheld electronic device, such as a GPS-enabled wireless communications device with an embedded camera, a GPS-enabled camera-phone or a GPS-enabled digital camera, determines whether ephemeris data needs to be obtained for geotagging digital photos taken with the device. By monitoring user activity with respect to the camera, such as activation of the camera, the device can begin pre-acquisition of a GPS position fix by obtaining needed ephemeris data before the photograph is actually taken. This GPS pre-acquisition improves the likelihood that a position fix (GPS lock) is achieved by the time the photo is taken (to enable immediate geotagging). Alternatively, the photo can be geotagged retroactively by appending the current location to the metadata tag associated with the digital photo. An optional acquisition status indicator can be displayed on a user interface of the device to indicate that a position fix is being obtained.