代码目录结构
LAUNCHER activity：CameraActivity ：
onCreate()方法中创建Camera工具类CameraHelper的实例并初始化：
mCameraHelper = new CameraHelper(mActivity, textureView, btnImagePreview);
重写onClick方法监听拍照点击事件：
mCameraHelper.takePicture();
CameraHelper类中实现相机的预览与拍照，流程如下：
大致流程如下：
- 用CameraManager的openCamera(String cameraId, CameraDevice.StateCallback callback, Handler handler)方法打开指定摄像头。该方法的第一个参数代表要打开的摄像头ID；第二个参数用于监听摄像头的状态；第三个参数代表执行callback的Handler，如果程序希望直接在当前线程中执行callback，则可将handler参数设为null。
- 当摄像头被打开之后会回调接口mStateCallback.onOpened，程序即可获取CameraDevice —— 即根据摄像头ID获取了指定摄像头设备，然后调用CameraDevice的createCaptureSession(List outputs, CameraCaptureSession. StateCallback callback，Handler handler)方法来创建CameraCaptureSession。该方法的第一个参数是一个List集合，封装了所有需要从该摄像头获取图片的Surface，第二个参数用于监听CameraCaptureSession的创建过程；第三个参数代表执行callback的Handler，如果程序希望直接在当前线程中执行callback，则可将handler参数设为null。
- 不管预览还是拍照，程序都调用CameraDevice的createCaptureRequest(int templateType)方法创建CaptureRequest.Builder，该方法支持TEMPLATE_PREVIEW（预览）、TEMPLATE_RECORD（拍摄视频）、TEMPLATE_STILL_CAPTURE（拍照）等参数。
- 通过第3步所调用方法返回的CaptureRequest.Builder设置拍照的各种参数，比如对焦模式、曝光模式等。
- 调用CaptureRequest.Builder的build()方法即可得到CaptureRequest对象，接下来程序可通过CameraCaptureSession的setRepeatingRequest()方法开始预览，或调用capture()方法拍照。
相机的预览与拍照流程我们基本了解了。
- 调用CaptureRequest.Builder的build()方法即可得到CaptureRequest对象，接下来程序可通过CameraCaptureSession的setRepeatingRequest()方法开始预览，或调用capture()方法拍照。
- 预览时，是将mSurfaceHolder.getSurface()作为目标，使用setRepeatingRequest()方法，
显示拍照结果时，是将mImageReader.getSurface()作为目标，使用capture()方法
- 预览时，是将mSurfaceHolder.getSurface()作为目标，使用setRepeatingRequest()方法，
layout布局如下：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/relativeLayout"
android:orientation="vertical"
android:background="#000">
<ImageView
android:id="@+id/imageView"
android:layout_width="match_parent"
android:layout_height="112dp"
android:background="@color/black"/>
<LinearLayout
android:id="@+id/linearLayout"
android:layout_width="match_parent"
android:layout_height="208dp"
android:layout_alignParentBottom="true"
android:orientation="vertical">
<com.bilibili.camera2.view.SideBar
android:id="@+id/sideBar"
android:layout_width="300dp"
android:layout_height="60dp"
android:visibility="gone"
android:layout_marginTop="10dp"
android:layout_gravity="center_horizontal"/>
<com.bilibili.camera2.view.HorizontalSelectedView
android:id="@+id/selectedView"
android:layout_width="match_parent"
android:layout_marginTop="10dp"
android:layout_height="60dp"
android:layout_gravity="center_horizontal"
app:HorizontalSelectedViewSeeSize="5"
android:visibility="visible"
app:HorizontalSelectedViewSelectedTextColor="@color/white"
app:HorizontalSelectedViewSelectedTextSize="40"
app:HorizontalSelectedViewTextColor="@color/gray"
app:HorizontalSelectedViewTextSize="30" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!-- 拍照按钮 -->
<ImageButton
android:id="@+id/btnTakePicture"
android:layout_width="80dp"
android:layout_height="80dp"
android:layout_centerHorizontal="true"
android:background="@drawable/ic_camera_main_btn_01_auto"
android:layout_gravity="center"
tools:ignore="ContentDescription" />
<ImageView
android:id="@+id/faceBackCameraChange"
android:layout_width="70dp"
android:layout_height="70dp"
android:layout_marginStart="280dp"
android:layout_centerVertical="true"
android:background="@drawable/ic_camera_main_btn_02_switch"
android:clickable="true"
tools:ignore="ContentDescription" />
</RelativeLayout>
</LinearLayout>
<LinearLayout
android:id="@+id/linearLayoutBottom"
android:layout_width="match_parent"
android:layout_height="48dp"
android:background="@color/black"
android:layout_alignParentBottom="true"
android:orientation="horizontal" />
</RelativeLayout>
CameraHelper主要逻辑代码如下：
class CameraHelper {
private final Activity mActivity;
private final TextureView mTextureView;
private static final String TAG = "CameraHelper";
private static final int PREVIEW_WIDTH = 1080; //预览的宽度
private static final int PREVIEW_HEIGHT = 2340; //预览的高度
private static final int SAVE_WIDTH = 1080; //保存图片的宽度
private static final int SAVE_HEIGHT = 23400; //保存图片的高度
private static final int PREVIEW_FIRST_GET_IMAGE = 0;
private CameraManager mCameraManager;
private ImageReader mImageReader;
private CameraDevice mCameraDevice;
private CameraCaptureSession mCameraCaptureSession;
private CircleImageView imageButton;
private String mCameraId = "0";
private CameraCharacteristics mCameraCharacteristics;
private int mCameraSensorOrientation = 0; //摄像头方向
private int mCameraFacing = CameraCharacteristics.LENS_FACING_BACK; //默认使用后置摄像头
//private int mDisplayRotation = mActivity.getWindowManager().getDefaultDisplay().getRotation(); //手机方向
private boolean canTakePicture = true; //是否可以拍照
private boolean canExchangeCamera = false; //是否可以切换摄像头
private Handler mCameraHandler;
private HandlerThread handlerThread = new HandlerThread("CameraThread");
private Size mPreviewSize = new Size(PREVIEW_WIDTH, PREVIEW_HEIGHT); //预览大小
private Size mSavePicSize = new Size(SAVE_WIDTH, SAVE_HEIGHT); //保存图片大小
private CoordinateTransformer mTransformer;
private int i = 0;
public CameraHelper(Activity mActivity, TextureView mTextureView, CircleImageView imageButton) {
this.mActivity = mActivity;
this.mTextureView = mTextureView;
this.imageButton = imageButton;
init();
}
private void init() {
handlerThread.start();
mCameraHandler = new Handler(Looper.myLooper());
mTextureView.setSurfaceTextureListener(new TextureView.SurfaceTextureListener() {
@Override
public void onSurfaceTextureAvailable(@NonNull SurfaceTexture surface, int width, int height) {
initCameraInfo();
}
@Override
public boolean onSurfaceTextureDestroyed(@NonNull SurfaceTexture surface) {
releaseCamera();
return true;
}
@Override
public void onSurfaceTextureSizeChanged(@NonNull SurfaceTexture surface, int width, int height) {
}
@Override
public void onSurfaceTextureUpdated(@NonNull SurfaceTexture surface) {
}
});
}
public CameraDevice getCameraDevice(){
Log.d(TAG, "getCameraDevice: mCameraDevice : " + mCameraDevice);
return mCameraDevice;
}
public void releaseCamera() {
if (mCameraCaptureSession != null) {
mCameraCaptureSession.close();
mCameraCaptureSession = null;
}
if (mCameraDevice != null){
mCameraDevice.close();
mCameraDevice = null;
}
if (mImageReader != null){
mImageReader.close();
mImageReader = null;
}
canExchangeCamera = false;
}
public void releaseThread() {
handlerThread.quitSafely();
mCameraHandler = null;
}
/**
* 拍照
*/
public void takePicture(){
Log.i(TAG, "takePicture: 进行拍照 1");
if (mCameraDevice == null || !canTakePicture || ! mTextureView.isAvailable()) {
Log.d(TAG, "takePicture: 进行拍照 error 退出");
return;
}
try {
CaptureRequest.Builder captureBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(mImageReader.getSurface());
captureBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, mCameraSensorOrientation);
mCameraCaptureSession.capture(captureBuilder.build(),null, mCameraHandler);
Thread.sleep(200);
Log.i(TAG, "takePicture: picture capture finish");
} catch (CameraAccessException | InterruptedException e) {
e.printStackTrace();
}
}
/**
* 切换摄像头
*/
public void exchangeCamera(){
if (mCameraDevice == null || !canExchangeCamera || !mTextureView.isAvailable()) return;
mCameraFacing = (mCameraFacing == CameraCharacteristics.LENS_FACING_FRONT)
? CameraCharacteristics.LENS_FACING_BACK : CameraCharacteristics.LENS_FACING_FRONT;
mPreviewSize = new Size(PREVIEW_WIDTH, PREVIEW_HEIGHT); //重置预览大小
releaseCamera();
initCameraInfo();
}
/**
* 初始化
*/
@SuppressLint("ShowToast")
private void initCameraInfo() {
try {
mCameraManager = (CameraManager) mActivity.getSystemService(Context.CAMERA_SERVICE);
String[] cameraIdList = mCameraManager.getCameraIdList();
if (cameraIdList == null) {
Toast.makeText(mActivity, "没有相机可用", Toast.LENGTH_SHORT);
return;
}
for (String id : cameraIdList) {
CameraCharacteristics cameraCharacteristics = mCameraManager.getCameraCharacteristics(id);
//+Type add focus
RectF mPreviewRect = new RectF(0,0,1080, 1440);
mTransformer = new CoordinateTransformer(cameraCharacteristics, mPreviewRect);
Rect mFocusRect = new Rect();
RectF rectF = mTransformer.toCameraSpace(mPreviewRect);
mFocusRect.left = Math.round(rectF.left);
mFocusRect.top = Math.round(rectF.top);
mFocusRect.right = Math.round(rectF.right);
mFocusRect.bottom = Math.round(rectF.bottom);
//MeteringRectangle meteringRectangle = new MeteringRectangle(mFocusRect,1000);
//-Type add focus
Integer facing = cameraCharacteristics.get(CameraCharacteristics.LENS_FACING);
if (facing == mCameraFacing) {
mCameraId = id;
mCameraCharacteristics = cameraCharacteristics;
}
Log.i(TAG, "initCameraInfo: 设备中的摄像头: " + id);
}
Integer supportLevel = mCameraCharacteristics.get(CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL);
if (supportLevel == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY) {
Toast.makeText(mActivity, "相机硬件不支持新特性", Toast.LENGTH_SHORT);
}
//获取摄像头方向
mCameraSensorOrientation = mCameraCharacteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);
//获取StreamConfigurationMap，它是管理摄像头支持的所有输出格式和尺寸
StreamConfigurationMap configurationMap = mCameraCharacteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
Size[] savePicSizes = configurationMap.getOutputSizes(ImageFormat.JPEG); //保存照片尺寸
if (savePicSizes == null) {
Log.d(TAG, "initCameraInfo: savePicSizes为空");
return;
}
Size[] previewSizes = configurationMap.getOutputSizes(SurfaceTexture.class); //预览尺寸
if (previewSizes == null) {
Log.d(TAG, "initCameraInfo: previewSizes为空");
return;
}
int mDisplayRotation = mActivity.getWindowManager().getDefaultDisplay().getRotation(); //手机方向
boolean exchange = exchangeWidthAndHeight(mDisplayRotation, mCameraSensorOrientation);
if (exchange) {
mSavePicSize = getBestSize(mSavePicSize.getHeight(),
mSavePicSize.getWidth(),
mSavePicSize.getHeight(),
mSavePicSize.getWidth(),
Arrays.asList(savePicSizes));
} else {
mSavePicSize = getBestSize(mSavePicSize.getWidth(),
mSavePicSize.getHeight(),
mSavePicSize.getWidth(),
mSavePicSize.getHeight(),
Arrays.asList(savePicSizes));
}
if (exchange) {
mPreviewSize = getBestSize(mPreviewSize.getHeight(),
mPreviewSize.getWidth(),
mTextureView.getHeight(),
mTextureView.getWidth(),
Arrays.asList(previewSizes));
} else {
mPreviewSize = getBestSize(mPreviewSize.getWidth(),
mPreviewSize.getHeight(),
mTextureView.getWidth(),
mTextureView.getHeight(),
Arrays.asList(previewSizes));
}
mPreviewSize = new Size(1080,1440);
if (mTextureView.getSurfaceTexture() == null){
Log.i(TAG, "initCameraInfo: mTextureView.getSurfaceTexture() 执行了*******************");
SurfaceTexture surfaceTexture = mTextureView.getSurfaceTexture();
surfaceTexture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());
mTextureView.setSurfaceTexture(surfaceTexture);
}
Log.d(TAG, "预览最优尺寸: " + mPreviewSize.getWidth() + " " + mPreviewSize.getHeight() +
"比例 " + mPreviewSize.getWidth() / mPreviewSize.getHeight());
Log.d(TAG, "保存图片最优尺寸: " + mSavePicSize.getWidth() + " " + mSavePicSize.getHeight() +
"比例 " + mSavePicSize.getWidth() / mSavePicSize.getHeight());
mImageReader = ImageReader.newInstance(mSavePicSize.getWidth(), mSavePicSize.getHeight(), ImageFormat.JPEG, 1);
mImageReader.setOnImageAvailableListener(onImageAvailableListener, mCameraHandler);
Log.d(TAG, "initCameraInfo: mTextureView-----------5");
openCamera();
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
/**
* 打开相机
*/
private void openCamera() {
if (ActivityCompat.checkSelfPermission(mActivity, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
Log.d(TAG, "initCameraInfo: mTextureView-----------没有相机权限");
List<String> permissionList = new ArrayList<>();
permissionList.add(Manifest.permission.READ_EXTERNAL_STORAGE);
permissionList.add(Manifest.permission.CAMERA);
permissionList.add(Manifest.permission.CALL_PHONE);
permissionList.add(Manifest.permission.MODIFY_AUDIO_SETTINGS);
permissionList.add(Manifest.permission.ACCESS_BACKGROUND_LOCATION);
permissionList.add(Manifest.permission.READ_PHONE_STATE);
permissionList.add(Manifest.permission.INTERNET);
permissionList.add(Manifest.permission.VIBRATE);
permissionList.add(Manifest.permission.ACCESS_WIFI_STATE);
ActivityCompat.requestPermissions(mActivity, permissionList.toArray(new String[permissionList.size()]),1002);
}else {
try {
Log.d(TAG, "initCameraInfo: mTextureView-----------6准备打开相机");
mCameraManager.openCamera(mCameraId, mStateCallback, mCameraHandler);
Log.d(TAG, "openCamera: 打开相机");
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
}
private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() {
@Override
public void onOpened(@NonNull CameraDevice camera) {
Log.i(TAG, "onOpened: ");
mCameraDevice = camera;
createCaptureSession(mCameraDevice);
}
@Override
public void onDisconnected(@NonNull CameraDevice camera) {
Log.i(TAG, "onDisconnected: ");
}
@Override
public void onError(@NonNull CameraDevice camera, int error) {
Log.i(TAG, "onError: ");
Toast.makeText(mActivity, "打开相机失败！error: " + error, Toast.LENGTH_SHORT);
}
};
private void createCaptureSession(CameraDevice cameraDevice){
try {
Log.d(TAG, "createCaptureSession的CameraDevice ：" + cameraDevice);
CaptureRequest.Builder builder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
@SuppressLint("Recycle")
Surface surface = new Surface(mTextureView.getSurfaceTexture());
builder.addTarget(surface);
builder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
builder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
List<Surface> list = new ArrayList<>();
list.add(surface);
list.add(mImageReader.getSurface());
cameraDevice.createCaptureSession(list, new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(@NonNull CameraCaptureSession session) {
mCameraCaptureSession = session;
try {
session.setRepeatingRequest(builder.build(), mCaptureCallback, mCameraHandler );
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onConfigureFailed(@NonNull CameraCaptureSession session) {
Log.d(TAG, "onConfigureFailed: 开启预览会话失败");
}
}, mCameraHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private CameraCaptureSession.CaptureCallback mCaptureCallback = new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) {
super.onCaptureCompleted(session, request, result);
canExchangeCamera = true;
canTakePicture = true;
}
@SuppressLint("ShowToast")
@Override
public void onCaptureFailed(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull CaptureFailure failure) {
super.onCaptureFailed(session, request, failure);
Log.d(TAG, "onCaptureFailed");
Toast.makeText(mActivity,"开启预览失败",Toast.LENGTH_SHORT);
}
};
private final ImageReader.OnImageAvailableListener onImageAvailableListener = reader -> {
Image image = reader.acquireLatestImage();
ByteBuffer byteBuffer = image.getPlanes()[0].getBuffer();
byte[] bytesArray = new byte[byteBuffer.remaining()];
byteBuffer.get(bytesArray);
image.close();
String localPicturePath = BitmapUtils.savePicture(bytesArray, "Camera");
if (localPicturePath.equals("")){
Log.d(TAG, "没有获取到最后一张图片的路径！！！！！: " + localPicturePath);
imageButton.setImageResource(PREVIEW_FIRST_GET_IMAGE);
}else {
Bitmap bitmap = BitmapFactory.decodeFile(localPicturePath);
int width = bitmap.getWidth();
int height = bitmap.getHeight();
float w = (float) 256 / width;
//float h = (float) 256 / height;
Matrix matrix = new Matrix();
matrix.postScale(w, w);
Bitmap newBitmap1 = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
Matrix matrix1 = new Matrix();
matrix1.setRotate(90f);
Bitmap resultBitmap = Bitmap.createBitmap(newBitmap1, 0, 0, newBitmap1.getWidth(), newBitmap1.getHeight(), matrix1, true);
imageButton.setImageBitmap(resultBitmap);
Log.d(TAG, "onImageAvailable: ------------------------------------------------------------图片保存");
}
};
private class CompareSizeByArea implements Comparator<Size> {
@Override
public int compare(Size size1, Size size2) {
return (int) Math.signum( size1.getWidth() * size1.getHeight() - size2.getWidth() * size2.getHeight());
}
}
/**
* 根据提供的屏幕方向 [displayRotation] 和相机方向 [sensorOrientation] 返回是否需要交换宽高
*/
private boolean exchangeWidthAndHeight(int displayRotation, int sensorOrientation){
boolean exchange = false;
switch (displayRotation){
case Surface.ROTATION_0:
case Surface.ROTATION_180:
if (sensorOrientation == 90 || sensorOrientation == 270){
exchange = true;
}
break;
case Surface.ROTATION_90:
case Surface.ROTATION_270:
if (sensorOrientation == 0 || sensorOrientation == 180){
exchange = true;
}
break;
}
Log.i(TAG, "屏幕方向: " + displayRotation);
Log.i(TAG, "相机方向: " + sensorOrientation);
return exchange;
}
}
TION_180:
if (sensorOrientation == 90 || sensorOrientation == 270){
exchange = true;
}
break;
case Surface.ROTATION_90:
case Surface.ROTATION_270:
if (sensorOrientation == 0 || sensorOrientation == 180){
exchange = true;
}
break;
}
Log.i(TAG, "屏幕方向: " + displayRotation);
Log.i(TAG, "相机方向: " + sensorOrientation);
return exchange;
}
}
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