#MyCamera 最近发现不同手机，调用系统相机效果不太好,，所以学习Android 的相机原理，自定义了一个Android相机。看了这篇博客，相信大家都会写一个自己的相机。对比了一下小猿搜题、学霸君、作业帮、阿凡题这四款app的拍照功能，个人感觉小猿搜题的体验要好一些，因为从主界面进入拍照界面，连个界面没有一个旋转的过渡，而学霸君就有一个过渡，有一丝丝的影响体验。也就是说学霸君的拍照界面是横屏的，在activity的onCreate方法里面调用了setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE)来设置全屏，而切换界面的时候又从竖屏切换为横屏，就会有个过渡的效果，影响了体验。
项目地址：https://github.com/Terrybthvi/MyCamera
这个项目仿照小猿搜题app，首先我们将相机布局最低层是显示摄像头获取到的图像，上层是网格线，聚焦图标等。
效果图如下所示：
1、绘制网格参考线
绘制网格参考线就是绘制拍照时屏幕中的竖线和直线，代码如下所示：
2、自定义相机代码
这里我们要创建一个SurfaceView，将摄像头获取到的图像放到SurfsaceView中显示。主要方法如下：
1、继承SurfaceView，定义变量，初始化类。
2、实现三个方法对sufarceView监听。
surfaceCreated(); surfaceChanged(); surfaceDestroyed();
3、获取相机实例
4、设置相机监听
5、增加自动聚焦 和点击屏幕聚焦
6、拍照以及设置图片格式
3、为相机添加聚焦功能
4、Activity调用相机
actiity中注册了SensorEventListener，也就是使用传感器监听用户手机的移动，如果有一定距离的移动，则自动聚焦，这样体验好一点。
package com.example.terry.mycamera;
import android.animation.AnimatorSet; import android.animation.ObjectAnimator; import android.annotation.TargetApi; import android.app.Activity; import android.content.ContentResolver; import android.content.ContentValues; import android.content.Context; import android.content.Intent; import android.content.res.Configuration; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.hardware.Sensor; import android.hardware.SensorEvent; import android.hardware.SensorEventListener; import android.hardware.SensorManager; import android.net.Uri; import android.os.Build; import android.os.Bundle; import android.os.Environment; import android.provider.MediaStore; import android.text.format.DateFormat; import android.util.Log; import android.view.View; import android.view.Window; import android.view.WindowManager; import android.view.animation.LinearInterpolator; import android.widget.LinearLayout; import android.widget.RelativeLayout; import android.widget.TextView;
import com.example.terry.mycamera.Crop.CropImageView; import com.example.terry.mycamera.Crop.CropperImage; import com.example.terry.mycamera.camare.CameraPreview; import com.example.terry.mycamera.camare.FocusView;
import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream;
/**
-
@Class: TakePhotoActivity
-
@Description: 拍照界面
-
@author: leiqi(http://blog.csdn.net/u013132758)
-
@Date: 2016/3/15 */ public class TakePhotoActivity extends Activity implements CameraPreview.OnCameraStatusListener, SensorEventListener { private static final String TAG = "TakePhoteActivity"; public static final Uri IMAGE_URI = MediaStore.Images.Media.EXTERNAL_CONTENT_URI; public static final String PATH = Environment.getExternalStorageDirectory() .toString() + "/AndroidMedia/"; CameraPreview mCameraPreview; CropImageView mCropImageView; RelativeLayout mTakePhotoLayout; LinearLayout mCropperLayout; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // 设置横屏 // setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE); // 设置全屏 requestWindowFeature(Window.FEATURE_NO_TITLE); getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); setContentView(R.layout.activity_take_photo); // Initialize components of the app mCropImageView = (CropImageView) findViewById(R.id.CropImageView); mCameraPreview = (CameraPreview) findViewById(R.id.cameraPreview); FocusView focusView = (FocusView) findViewById(R.id.view_focus); mTakePhotoLayout = (RelativeLayout) findViewById(R.id.take_photo_layout); mCropperLayout = (LinearLayout) findViewById(R.id.cropper_layout);
mCameraPreview.setFocusView(focusView); mCameraPreview.setOnCameraStatusListener(this); mCropImageView.setGuidelines(2); mSensorManager = (SensorManager) getSystemService(Context. SENSOR_SERVICE); mAccel = mSensorManager.getDefaultSensor(Sensor. TYPE_ACCELEROMETER);}
boolean isRotated = false;
@TargetApi(Build.VERSION_CODES.HONEYCOMB) @Override protected void onResume() { super.onResume(); if(!isRotated) { TextView hint_tv = (TextView) findViewById(R.id.hint); ObjectAnimator animator = ObjectAnimator.ofFloat(hint_tv, "rotation", 0f, 90f); animator.setStartDelay(800); animator.setDuration(1000); animator.setInterpolator(new LinearInterpolator()); animator.start(); View view = findViewById(R.id.crop_hint); AnimatorSet animSet = new AnimatorSet(); ObjectAnimator animator1 = ObjectAnimator.ofFloat(view, "rotation", 0f, 90f); ObjectAnimator moveIn = ObjectAnimator.ofFloat(view, "translationX", 0f, -50f); animSet.play(animator1).before(moveIn); animSet.setDuration(10); animSet.start(); isRotated = true; } mSensorManager.registerListener(this, mAccel, SensorManager.SENSOR_DELAY_UI); }
@Override protected void onPause() { super.onPause(); mSensorManager.unregisterListener(this); }
@Override public void onConfigurationChanged(Configuration newConfig) { Log.e(TAG, "onConfigurationChanged"); super.onConfigurationChanged(newConfig); }
public void takePhoto(View view) { if(mCameraPreview != null) { mCameraPreview.takePicture(); } }
public void openlight(View view) { if (mCameraPreview != null) { mCameraPreview.openLight(); view.setVisibility(View.GONE); View v = findViewById(R.id.nolight); v.setVisibility(View.VISIBLE); } } public void offlight(View v) { if (mCameraPreview != null) { mCameraPreview.offLight(); v.setVisibility(View.GONE); View view = findViewById(R.id.light); view.setVisibility(View.VISIBLE); } } public void close(View view) { finish(); }
/**
- 关闭截图界面
- @param view */ public void closeCropper(View view) { showTakePhotoLayout(); }
/**
- 开始截图，并保存图片
- @param view */ public void startCropper(View view) { //获取截图并旋转90度 CropperImage cropperImage = mCropImageView.getCroppedImage(); Log.e(TAG, cropperImage.getX() + "," + cropperImage.getY()); Log.e(TAG, cropperImage.getWidth() + "," + cropperImage.getHeight()); Bitmap bitmap = Utils.rotate(cropperImage.getBitmap(), -90); // Bitmap bitmap = mCropImageView.getCroppedImage(); // 系统时间 long dateTaken = System.currentTimeMillis(); // 图像名称 String filename = DateFormat.format("yyyy-MM-dd kk.mm.ss", dateTaken) .toString() + ".jpg"; Uri uri = insertImage(getContentResolver(), filename, dateTaken, PATH, filename, bitmap, null); cropperImage.getBitmap().recycle(); cropperImage.setBitmap(null); Intent intent = new Intent(this, PreviewActivity.class); intent.setData(uri); intent.putExtra("path", PATH + filename); intent.putExtra("width", bitmap.getWidth()); intent.putExtra("height", bitmap.getHeight()); intent.putExtra("cropperImage", cropperImage); startActivity(intent); bitmap.recycle(); finish(); super.overridePendingTransition(R.anim.fade_in, R.anim.fade_out); // doAnimation(cropperImage); }
/**
- 拍照成功后回调
- 存储图片并显示截图界面
- @param data */ @Override public void onCameraStopped(byte[] data) { Log.i("TAG", "==onCameraStopped=="); // 创建图像 Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length); // 系统时间 long dateTaken = System.currentTimeMillis(); // 图像名称 String filename = DateFormat.format("yyyy-MM-dd kk.mm.ss", dateTaken) .toString() + ".jpg"; // 存储图像（PATH目录） Uri source = insertImage(getContentResolver(), filename, dateTaken, PATH, filename, bitmap, data); //准备截图 try { mCropImageView.setImageBitmap(MediaStore.Images.Media.getBitmap(this.getContentResolver(), source)); // mCropImageView.rotateImage(90); } catch (IOException e) { Log.e(TAG, e.getMessage()); } showCropperLayout(); }
/**
- 存储图像并将信息添加入媒体数据库 */ private Uri insertImage(ContentResolver cr, String name, long dateTaken, String directory, String filename, Bitmap source, byte[] jpegData) { OutputStream outputStream = null; String filePath = directory + filename; try { File dir = new File(directory); if (!dir.exists()) { dir.mkdirs(); } File file = new File(directory, filename); if (file.createNewFile()) { outputStream = new FileOutputStream(file); if (source != null) { source.compress(Bitmap.CompressFormat.JPEG, 100, outputStream); } else { outputStream.write(jpegData); } } } catch (FileNotFoundException e) { Log.e(TAG, e.getMessage()); return null; } catch (IOException e) { Log.e(TAG, e.getMessage()); return null; } finally { if (outputStream != null) { try { outputStream.close(); } catch (Throwable t) { } } } ContentValues values = new ContentValues(7); values.put(MediaStore.Images.Media.TITLE, name); values.put(MediaStore.Images.Media.DISPLAY_NAME, filename); values.put(MediaStore.Images.Media.DATE_TAKEN, dateTaken); values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg"); values.put(MediaStore.Images.Media.DATA, filePath); return cr.insert(IMAGE_URI, values); }
private void showTakePhotoLayout() { mTakePhotoLayout.setVisibility(View.VISIBLE); mCropperLayout.setVisibility(View.GONE); }
private void showCropperLayout() { mTakePhotoLayout.setVisibility(View.GONE); mCropperLayout.setVisibility(View.VISIBLE); mCameraPreview.start(); //继续启动摄像头 }
private float mLastX = 0; private float mLastY = 0; private float mLastZ = 0; private boolean mInitialized = false; private SensorManager mSensorManager; private Sensor mAccel; @Override public void onSensorChanged(SensorEvent event) {
float x = event.values[0]; float y = event.values[1]; float z = event.values[2]; if (!mInitialized){ mLastX = x; mLastY = y; mLastZ = z; mInitialized = true; } float deltaX = Math.abs(mLastX - x); float deltaY = Math.abs(mLastY - y); float deltaZ = Math.abs(mLastZ - z); if(deltaX > 0.8 || deltaY > 0.8 || deltaZ > 0.8){ mCameraPreview.setFocus(); } mLastX = x; mLastY = y; mLastZ = z;}
@Override public void onAccuracyChanged(Sensor sensor, int accuracy) { } } 5、添加计算焦点及测光区域、拍照后图片旋转以及检测摄像头是否可用
public class Utils {
public static DisplayMetrics getScreenWH(Context context) {
DisplayMetrics dMetrics = new DisplayMetrics();
dMetrics = context.getResources().getDisplayMetrics();
return dMetrics;
}
/**
* 计算焦点及测光区域
*
* @param focusWidth
* @param focusHeight
* @param areaMultiple
* @param x
* @param y
* @param previewleft
* @param previewRight
* @param previewTop
* @param previewBottom
* @return Rect(left,top,right,bottom) : left、top、right、bottom是以显示区域中心为原点的坐标
*/
public static Rect calculateTapArea(int focusWidth, int focusHeight,
float areaMultiple, float x, float y, int previewleft,
int previewRight, int previewTop, int previewBottom) {
int areaWidth = (int) (focusWidth * areaMultiple);
int areaHeight = (int) (focusHeight * areaMultiple);
int centerX = (previewleft + previewRight) / 2;
int centerY = (previewTop + previewBottom) / 2;
double unitx = ((double) previewRight - (double) previewleft) / 2000;
double unity = ((double) previewBottom - (double) previewTop) / 2000;
int left = clamp((int) (((x - areaWidth / 2) - centerX) / unitx),
-1000, 1000);
int top = clamp((int) (((y - areaHeight / 2) - centerY) / unity),
-1000, 1000);
int right = clamp((int) (left + areaWidth / unitx), -1000, 1000);
int bottom = clamp((int) (top + areaHeight / unity), -1000, 1000);
return new Rect(left, top, right, bottom);
}
public static int clamp(int x, int min, int max) {
if (x > max)
return max;
if (x < min)
return min;
return x;
}
/**
* 检测摄像头设备是否可用
* Check if this device has a camera
* @param context
* @return
*/
public static boolean checkCameraHardware(Context context) {
if (context != null && context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
// this device has a camera
return true;
} else {
// no camera on this device
return false;
}
}
/**
* @param context
* @return app_cache_path/dirName
*/
public static String getDBDir(Context context) {
String path = null;
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {
path = Environment.getExternalStorageDirectory().getAbsolutePath() +
File.separator + "bbk" + File.separator + "cloudteacher" + File.separator + "db";
File externalCacheDir = context.getExternalCacheDir();
if (externalCacheDir != null) {
path = externalCacheDir.getPath();
}
}
if (path == null) {
File cacheDir = context.getCacheDir();
if (cacheDir != null && cacheDir.exists()) {
path = cacheDir.getPath();
}
}
return path;
}
/**
* bitmap旋转
* @param b
* @param degrees
* @return
*/
public static Bitmap rotate(Bitmap b, int degrees) {
if (degrees != 0 && b != null) {
Matrix m = new Matrix();
m.setRotate(degrees, (float) b.getWidth() / 2, (float) b.getHeight() / 2);
try {
Bitmap b2 = Bitmap.createBitmap(
b, 0, 0, b.getWidth(), b.getHeight(), m, true);
if (b != b2) {
b.recycle(); //Android开发再次提示Bitmap操作完应该显示的释放
b = b2;
}
} catch (OutOfMemoryError ex) {
// Android123建议大家如何出现了内存不足异常，最好return 原始的bitmap对象。.
}
}
return b;
}
public static final int getHeightInPx(Context context) {
final int height = context.getResources().getDisplayMetrics().heightPixels;
return height;
}
public static final int getWidthInPx(Context context) {
final int width = context.getResources().getDisplayMetrics().widthPixels;
return width;
}
}
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