/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.ex.camera2.portability;
import android.graphics.Matrix;
import android.graphics.RectF;
import com.android.ex.camera2.portability.debug.Log;
/**
* The device info for all attached cameras.
*/
public interface CameraDeviceInfo {
static final int NO_DEVICE = -1;
/**
* @param cameraId Which device to interrogate.
* @return The static characteristics of the specified device, or {@code null} on error.
*/
Characteristics getCharacteristics(int cameraId);
/**
* @return The total number of the available camera devices.
*/
int getNumberOfCameras();
/**
* @return The first (lowest) ID of the back cameras or {@code NO_DEVICE}
* if not available.
*/
int getFirstBackCameraId();
/**
* @return The first (lowest) ID of the front cameras or {@code NO_DEVICE}
* if not available.
*/
int getFirstFrontCameraId();
/**
* Device characteristics for a single camera.
*/
public abstract class Characteristics {
private static final Log.Tag TAG = new Log.Tag("CamDvcInfChar");
/**
* @return Whether the camera faces the back of the device.
*/
public abstract boolean isFacingBack();
/**
* @return Whether the camera faces the device's screen.
*/
public abstract boolean isFacingFront();
/**
* @return The camera sensor orientation, or the counterclockwise angle
* from its natural position that the device must be held at
* for the sensor to be right side up (in degrees, always a
* multiple of 90, and between 0 and 270, inclusive).
*/
public abstract int getSensorOrientation();
/**
* @param currentDisplayOrientation
* The current display orientation, measured counterclockwise
* from to the device's natural orientation (in degrees, always
* a multiple of 90, and between 0 and 270, inclusive).
* @return
* The relative preview image orientation, or the clockwise
* rotation angle that must be applied to display preview
* frames in the matching orientation, accounting for implicit
* mirroring, if applicable (in degrees, always a multiple of
* 90, and between 0 and 270, inclusive).
*/
public int getPreviewOrientation(int currentDisplayOrientation) {
// Drivers tend to mirror the image during front camera preview.
return getRelativeImageOrientation(currentDisplayOrientation, true);
}
/**
* @param currentDisplayOrientation
* The current display orientation, measured counterclockwise
* from to the device's natural orientation (in degrees, always
* a multiple of 90, and between 0 and 270, inclusive).
* @return
* The relative capture image orientation, or the clockwise
* rotation angle that must be applied to display these frames
* in the matching orientation (in degrees, always a multiple
* of 90, and between 0 and 270, inclusive).
*/
public int getJpegOrientation(int currentDisplayOrientation) {
// Don't mirror during capture!
return getRelativeImageOrientation(currentDisplayOrientation, false);
}
/**
* @param currentDisplayOrientaiton
* {@link #getPreviewOrientation}, {@link #getJpegOrientation}
* @param compensateForMirroring
* Whether to account for mirroring in the case of front-facing
* cameras, which is necessary iff the OS/driver is
* automatically reflecting the image.
* @return
* {@link #getPreviewOrientation}, {@link #getJpegOrientation}
*
* @see android.hardware.Camera.setDisplayOrientation
*/
protected int getRelativeImageOrientation(int currentDisplayOrientation,
boolean compensateForMirroring) {
if (!orientationIsValid(currentDisplayOrientation)) {
return 0;
}
int result = 0;
if (isFacingFront()) {
result = (getSensorOrientation() + currentDisplayOrientation) % 360;
if (compensateForMirroring) {
result = (360 - result) % 360;
}
} else if (isFacingBack()) {
result = (getSensorOrientation() - currentDisplayOrientation + 360) % 360;
} else {
Log.e(TAG, "Camera is facing unhandled direction");
}
return result;
}
/**
* @param currentDisplayOrientation
* The current display orientation, measured counterclockwise
* from to the device's natural orientation (in degrees, always
* a multiple of 90, and between 0 and 270, inclusive).
* @param surfaceDimensions
* The dimensions of the {@link android.view.Surface} on which
* the preview image is being rendered. It usually only makes
* sense for the upper-left corner to be at the origin.
* @return
* The transform matrix that should be applied to the
* {@link android.view.Surface} in order for the image to
* display properly in the device's current orientation.
*/
public Matrix getPreviewTransform(int currentDisplayOrientation, RectF surfaceDimensions) {
return getPreviewTransform(currentDisplayOrientation, surfaceDimensions,
new RectF(surfaceDimensions));
}
/**
* @param currentDisplayOrientation
* The current display orientation, measured counterclockwise
* from to the device's natural orientation (in degrees, always
* a multiple of 90, and between 0 and 270, inclusive).
* @param surfaceDimensions
* The dimensions of the {@link android.view.Surface} on which
* the preview image is being rendered. It usually only makes
* sense for the upper-left corner to be at the origin.
* @param desiredBounds
* The boundaries within the {@link android.view.Surface} where
* the final image should appear. These can be used to
* translate and scale the output, but note that the image will
* be stretched to fit, possibly changing its aspect ratio.
* @return
* The transform matrix that should be applied to the
* {@link android.view.Surface} in order for the image to
* display properly in the device's current orientation.
*/
public Matrix getPreviewTransform(int currentDisplayOrientation, RectF surfaceDimensions,
RectF desiredBounds) {
if (!orientationIsValid(currentDisplayOrientation) ||
surfaceDimensions.equals(desiredBounds)) {
return new Matrix();
}
Matrix transform = new Matrix();
transform.setRectToRect(surfaceDimensions, desiredBounds, Matrix.ScaleToFit.FILL);
return transform;
}
/**
* @return Whether the shutter sound can be disabled.
*/
public abstract boolean canDisableShutterSound();
protected static boolean orientationIsValid(int angle) {
if (angle % 90 != 0) {
Log.e(TAG, "Provided display orientation is not divisible by 90");
return false;
}
if (angle < 0 || angle > 270) {
Log.e(TAG, "Provided display orientation is outside expected range");
return false;
}
return true;
}
}
}
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