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|
# SPDX-License-Identifier: LGPL-2.1-or-later
#
# Copyright (C) 2019, Google Inc.
#
%YAML 1.1
---
# Unless otherwise stated, all controls are bi-directional, i.e. they can be
# set through Request::controls() and returned out through Request::metadata().
vendor: libcamera
controls:
- AeEnable:
type: bool
description: |
Enable or disable the AE.
\sa ExposureTime AnalogueGain
- AeLocked:
type: bool
description: |
Report the lock status of a running AE algorithm.
If the AE algorithm is locked the value shall be set to true, if it's
converging it shall be set to false. If the AE algorithm is not
running the control shall not be present in the metadata control list.
\sa AeEnable
# AeMeteringMode needs further attention:
# - Auto-generate max enum value.
# - Better handling of custom types.
- AeMeteringMode:
type: int32_t
description: |
Specify a metering mode for the AE algorithm to use. The metering
modes determine which parts of the image are used to determine the
scene brightness. Metering modes may be platform specific and not
all metering modes may be supported.
enum:
- name: MeteringCentreWeighted
value: 0
description: Centre-weighted metering mode.
- name: MeteringSpot
value: 1
description: Spot metering mode.
- name: MeteringMatrix
value: 2
description: Matrix metering mode.
- name: MeteringCustom
value: 3
description: Custom metering mode.
# AeConstraintMode needs further attention:
# - Auto-generate max enum value.
# - Better handling of custom types.
- AeConstraintMode:
type: int32_t
description: |
Specify a constraint mode for the AE algorithm to use. These determine
how the measured scene brightness is adjusted to reach the desired
target exposure. Constraint modes may be platform specific, and not
all constraint modes may be supported.
enum:
- name: ConstraintNormal
value: 0
description: Default constraint mode.
This mode aims to balance the exposure of different parts of the
image so as to reach a reasonable average level. However, highlights
in the image may appear over-exposed and lowlights may appear
under-exposed.
- name: ConstraintHighlight
value: 1
description: Highlight constraint mode.
This mode adjusts the exposure levels in order to try and avoid
over-exposing the brightest parts (highlights) of an image.
Other non-highlight parts of the image may appear under-exposed.
- name: ConstraintShadows
value: 2
description: Shadows constraint mode.
This mode adjusts the exposure levels in order to try and avoid
under-exposing the dark parts (shadows) of an image. Other normally
exposed parts of the image may appear over-exposed.
- name: ConstraintCustom
value: 3
description: Custom constraint mode.
# AeExposureMode needs further attention:
# - Auto-generate max enum value.
# - Better handling of custom types.
- AeExposureMode:
type: int32_t
description: |
Specify an exposure mode for the AE algorithm to use. These specify
how the desired total exposure is divided between the shutter time
and the sensor's analogue gain. The exposure modes are platform
specific, and not all exposure modes may be supported.
enum:
- name: ExposureNormal
value: 0
description: Default exposure mode.
- name: ExposureShort
value: 1
description: Exposure mode allowing only short exposure times.
- name: ExposureLong
value: 2
description: Exposure mode allowing long exposure times.
- name: ExposureCustom
value: 3
description: Custom exposure mode.
- ExposureValue:
type: float
description: |
Specify an Exposure Value (EV) parameter. The EV parameter will only be
applied if the AE algorithm is currently enabled.
By convention EV adjusts the exposure as log2. For example
EV = [-2, -1, 0.5, 0, 0.5, 1, 2] results in an exposure adjustment
of [1/4x, 1/2x, 1/sqrt(2)x, 1x, sqrt(2)x, 2x, 4x].
\sa AeEnable
- ExposureTime:
type: int32_t
description: |
Exposure time (shutter speed) for the frame applied in the sensor
device. This value is specified in micro-seconds.
Setting this value means that it is now fixed and the AE algorithm may
not change it. Setting it back to zero returns it to the control of the
AE algorithm.
\sa AnalogueGain AeEnable
\todo Document the interactions between AeEnable and setting a fixed
value for this control. Consider interactions with other AE features,
such as aperture and aperture/shutter priority mode, and decide if
control of which features should be automatically adjusted shouldn't
better be handled through a separate AE mode control.
- AnalogueGain:
type: float
description: |
Analogue gain value applied in the sensor device.
The value of the control specifies the gain multiplier applied to all
colour channels. This value cannot be lower than 1.0.
Setting this value means that it is now fixed and the AE algorithm may
not change it. Setting it back to zero returns it to the control of the
AE algorithm.
\sa ExposureTime AeEnable
\todo Document the interactions between AeEnable and setting a fixed
value for this control. Consider interactions with other AE features,
such as aperture and aperture/shutter priority mode, and decide if
control of which features should be automatically adjusted shouldn't
better be handled through a separate AE mode control.
- AeFlickerMode:
type: int32_t
description: |
Set the flicker mode, which determines whether, and how, the AGC/AEC
algorithm attempts to hide flicker effects caused by the duty cycle of
artificial lighting.
Although implementation dependent, many algorithms for "flicker
avoidance" work by restricting this exposure time to integer multiples
of the cycle period, wherever possible.
Implementations may not support all of the flicker modes listed below.
By default the system will start in FlickerAuto mode if this is
supported, otherwise the flicker mode will be set to FlickerOff.
enum:
- name: FlickerOff
value: 0
description: No flicker avoidance is performed.
- name: FlickerManual
value: 1
description: Manual flicker avoidance.
Suppress flicker effects caused by lighting running with a period
specified by the AeFlickerPeriod control.
\sa AeFlickerPeriod
- name: FlickerAuto
value: 2
description: Automatic flicker period detection and avoidance.
The system will automatically determine the most likely value of
flicker period, and avoid flicker of this frequency. Once flicker
is being corrected, it is implementation dependent whether the
system is still able to detect a change in the flicker period.
\sa AeFlickerDetected
- AeFlickerPeriod:
type: int32_t
|