1. Starting in auto-AE mode:
2. Lock AE
3. Wait for the first result to be output that has the AE locked
4. Copy exposure settings from that result into a request, set the request to manual AE
5. Submit the capture request, proceed to run manual AE as desired.

Whether auto-exposure (AE) is currently locked to its latest calculated values.

When set to true (ON), the AE algorithm is locked to its latest parameters, and will not change exposure settings until the lock is set to false (OFF).

Note that even when AE is locked, the flash may be fired if the CaptureRequest.ControlAeMode is ON_AUTO_FLASH / ON_ALWAYS_FLASH / ON_AUTO_FLASH_REDEYE.

When CaptureRequest.ControlAeExposureCompensation is changed, even if the AE lock is ON, the camera device will still adjust its exposure value.

If AE precapture is triggered (see CaptureRequest.ControlAePrecaptureTrigger) when AE is already locked, the camera device will not change the exposure time (CaptureRequest.SensorExposureTime) and sensitivity (CaptureRequest.SensorSensitivity) parameters. The flash may be fired if the CaptureRequest.ControlAeMode is ON_AUTO_FLASH/ON_AUTO_FLASH_REDEYE and the scene is too dark. If the CaptureRequest.ControlAeMode is ON_ALWAYS_FLASH, the scene may become overexposed.

Since the camera device has a pipeline of in-flight requests, the settings that get locked do not necessarily correspond to the settings that were present in the latest capture result received from the camera device, since additional captures and AE updates may have occurred even before the result was sent out. If an application is switching between automatic and manual control and wishes to eliminate any flicker during the switch, the following procedure is recommended:

See CaptureResult.ControlAeState for AE lock related state transition details.

This key is available on all devices.

[Android Documentation]