我正在创建一个实现Camera的应用程序,我想知道为什么在我拍照时图像会被保存到一个小位图?
当我按下捕获按钮时,由于某种原因图像缩小(我需要将图像保存到内部存储器,而不是外部/ SD卡),我最终需要将其缩小以显示在ImageView,显然使照片比相机预览更有颗粒感。有一个更好的方法吗?
我希望它与SnapChat相似,你所拍摄的照片会显示你拍摄时的样子......
这是主要活动:
public class MainActivity extends FragmentActivity {
private static final String TAG = "CameraActivity";
public static final int MEDIA_TYPE_IMAGE = 1;
private Camera mCamera;
private CameraPreview mPreview;
private Context mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mContext = this;
if(checkCameraHardware(mContext)){
// Create an instance of Camera
mCamera = getCameraInstance();
// Create our Preview view and set it as the content of our activity.
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview);
// Add a listener to the Capture button
Button captureButton = (Button) findViewById(R.id.button_capture);
captureButton.setOnClickListener(
new View.OnClickListener() {
@Override
public void onClick(View v) {
// get an image from the camera
mCamera.takePicture(null, null, mPicture);
}
}
);
}
}
private Camera.PictureCallback mPicture = new Camera.PictureCallback() {
@Override
public void onPictureTaken(final byte[] data, Camera camera) {
new AsyncTask<Void, Void, String>() {
@Override
protected String doInBackground(Void... params) {
try {
FileOutputStream fos = openFileOutput("img.jpg", Context.MODE_PRIVATE);
fos.write(data);
fos.close();
return "img.jpg";
} catch (FileNotFoundException e) {
Log.d(TAG, "File not found: " + e.getMessage());
return null;
} catch (IOException e) {
Log.d(TAG, "Error accessing file: " + e.getMessage());
return null;
}
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
if(result != null){
Intent intent = new Intent(mContext, ImageDisplayActivity.class);
intent.putExtra(ImageDisplayActivity.KEY_PATH, "img.jpg");
startActivity(intent);
}
}
}.execute();
}
};
private boolean checkCameraHardware(Context context) {
if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){
// this device has a camera
return true;
} else {
// no camera on this device
return false;
}
}
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return c; // returns null if camera is unavailable
}
/** Create a File for saving an image or video */
}
这是图像显示活动:
public class ImageDisplayActivity extends FragmentActivity {
public static final String KEY_PATH = "img.jpg";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_display);
Intent intent = getIntent();
String path = getIntent().getStringExtra(ImageDisplayActivity.KEY_PATH);
try {
java.io.FileInputStream in = this.openFileInput(path);
Bitmap bitmap = BitmapFactory.decodeStream(in);
ZoomInZoomOut touch = (ZoomInZoomOut)findViewById(R.id.IMAGEID);
touch = arrangeImageView(touch);
touch.setImageBitmap(bitmap);
in.close();
Canvas c = new Canvas(bitmap);
} catch (Exception e) {
e.printStackTrace();
}
}
private ZoomInZoomOut arrangeImageView(ZoomInZoomOut img){
try {
img.setRotation(90);
img.setScaleX(2f);
img.setScaleY(2f);
} catch (Exception e) {
e.printStackTrace();
}
return img;
}
}