Add camera metering area API.
The API are still hidden.
bug:3475893
Change-Id: Id4147528def5e0fe067e1a3ed315fa34c14a0640
diff --git a/camera/CameraParameters.cpp b/camera/CameraParameters.cpp
index 1e7abae..214cd4d 100644
--- a/camera/CameraParameters.cpp
+++ b/camera/CameraParameters.cpp
@@ -68,6 +68,8 @@
const char CameraParameters::KEY_MAX_EXPOSURE_COMPENSATION[] = "max-exposure-compensation";
const char CameraParameters::KEY_MIN_EXPOSURE_COMPENSATION[] = "min-exposure-compensation";
const char CameraParameters::KEY_EXPOSURE_COMPENSATION_STEP[] = "exposure-compensation-step";
+const char CameraParameters::KEY_MAX_NUM_METERING_AREAS[] = "max-num-metering-areas";
+const char CameraParameters::KEY_METERING_AREAS[] = "metering-areas";
const char CameraParameters::KEY_ZOOM[] = "zoom";
const char CameraParameters::KEY_MAX_ZOOM[] = "max-zoom";
const char CameraParameters::KEY_ZOOM_RATIOS[] = "zoom-ratios";
diff --git a/include/camera/CameraParameters.h b/include/camera/CameraParameters.h
index 7930f47..e272839 100644
--- a/include/camera/CameraParameters.h
+++ b/include/camera/CameraParameters.h
@@ -308,6 +308,44 @@
// 0.3333, EV is -2.
// Example value: "0.333333333" or "0.5". Read only.
static const char KEY_EXPOSURE_COMPENSATION_STEP[];
+ // The maximum number of metering areas supported. This is the maximum
+ // length of KEY_METERING_AREAS.
+ // Example value: "0" or "2". Read only.
+ static const char KEY_MAX_NUM_METERING_AREAS[];
+ // Current metering areas. Camera driver uses these areas to decide
+ // exposure.
+ //
+ // Before accessing this parameter, apps should check
+ // KEY_MAX_NUM_METERING_AREAS first to know the maximum number of metering
+ // areas first. If the value is 0, metering area is not supported.
+ //
+ // Each metering area is a rectangle with specified weight. The direction is
+ // relative to the sensor orientation, that is, what the sensor sees. The
+ // direction is not affected by the rotation or mirroring of
+ // CAMERA_CMD_SET_DISPLAY_ORIENTATION. Coordinates of the rectangle range
+ // from -1000 to 1000. (-1000, -1000) is the upper left point. (1000, 1000)
+ // is the lower right point. The length and width of metering areas cannot
+ // be 0 or negative.
+ //
+ // The weight ranges from 1 to 1000. The sum of the weights of all metering
+ // areas must be 1000. Metering areas can partially overlap and the driver
+ // will add the weights in the overlap region. But apps should not set two
+ // metering areas that have identical coordinates.
+ //
+ // A special case of all-zero single metering area means driver to decide
+ // the metering area. For example, the driver may use more signals to decide
+ // metering areas and change them dynamically. Apps can set all-zero if they
+ // want the driver to decide metering areas.
+ //
+ // Metering areas are relative to the current field of view (KEY_ZOOM).
+ // No matter what the zoom level is, (-1000,-1000) represents the top of the
+ // currently visible camera frame. The metering area cannot be set to be
+ // outside the current field of view, even when using zoom.
+ //
+ // No matter what metering areas are, the final exposure are compensated
+ // by KEY_EXPOSURE_COMPENSATION.
+ // Example value: "(-10,-10,0,0,300),(0,0,10,10,700)". Read/write.
+ static const char KEY_METERING_AREAS[];
// Current zoom value.
// Example value: "0" or "6". Read/write.
static const char KEY_ZOOM[];