• Request 1: Exposure = 10ms, Black level lock = OFF
• Request 2: Exposure = 10ms, Black level lock = ON
• Request 3: Exposure = 10ms, Black level lock = ON
• Request 4: Exposure = 20ms, Black level lock = ON
• Request 5: Exposure = 20ms, Black level lock = ON
• Request 6: Exposure = 20ms, Black level lock = ON

• Result 1: Exposure = 10ms, Black level lock = OFF
• Result 2: Exposure = 10ms, Black level lock = ON
• Result 3: Exposure = 10ms, Black level lock = ON
• Result 4: Exposure = 20ms, Black level lock = OFF
• Result 5: Exposure = 20ms, Black level lock = ON
• Result 6: Exposure = 20ms, Black level lock = ON

Whether black-level compensation is locked to its current values, or is free to vary.

When set to true (ON), the values used for black-level compensation will not change until the lock is set to false (OFF).

Since changes to certain capture parameters (such as exposure time) may require resetting of black level compensation, the camera device must report whether setting the black level lock was successful in the output result metadata.

For example, if a sequence of requests is as follows:

And the exposure change in Request 4 requires the camera device to reset the black level offsets, then the output result metadata is expected to be:

This indicates to the application that on frame 4, black levels were reset due to exposure value changes, and pixel values may not be consistent across captures.

The camera device will maintain the lock to the extent possible, only overriding the lock to OFF when changes to other request parameters require a black level recalculation or reset.

Optional - This value may be null on some devices.

Full capability - Present on all camera devices that report being CameraMetadata.INFO_SUPPORTED_HARDWARE_LEVEL_FULL devices in the CameraCharacteristics.InfoSupportedHardwareLevel key

[Android Documentation]