textureview 缩放_使用TextureView缩放Camera2预览

i have a Problem with my Preview Zoom for the Camera2 API. I am using a TextureView.

I want to zoom only the preview Stream that was showed in the TextureView.

I want to zoom the Area where i use the Zoom Gesture.

I use the SimpleOnScaleGestureListener!

I added following Code. The zoomingFactor and the x and y Position are right.

private void updateTextureViewSize(float xPosi,float yPosi, float scale){

float scaleX = 1.0f;

float scaleY = 1.0f;

float mVideoWidth = mCamcontrol.getmPreviewSize().getWidth();

float mVideoHeight = mCamcontrol.getmPreviewSize().getHeight();

int rotation = getWindowManager().getDefaultDisplay().getRotation();

RectF viewRect = new RectF(0, 0, 1440, 2560);

RectF bufferRect = new RectF(0, 0, mVideoHeight, mVideoWidth);

bufferRect.offset(xPosi - bufferRect.centerX(), yPosi - bufferRect.centerY());

//16:9 faktor

scaleX = ((mScale * scale) / 9f) * 16f;

scaleY = ((mScale * scale) / 16f) * 9f;

Matrix matrix = new Matrix();

matrix.setRectToRect(bufferRect, viewRect, Matrix.ScaleToFit.FILL);

scalefactorView.setText(String.valueOf(xPosi) + " " + String.valueOf(yPosi));

matrix.setScale(scaleY, scaleX, xPosi, yPosi);

matrix.postRotate(90 * (rotation - 2), xPosi, yPosi);

mTextureView.setTransform(matrix);

}

Zooming is Right, but not the Position where i Zoom. For Example! When i zoom on the position right/middle i see only the left/top rectangle of the Stream.

I added the following pictures to unterstand the problem.

解决方案

Android Camera2 api : Pinch Zoom In/Out

Use this sample code for Camera2Basic from google developers. https://github.com/googlesamples/android-Camera2Basic

Now declare two class variables –

public float finger_spacing = 0;

public int zoom_level = 1;

and update the given onTouch() method.

public boolean onTouch(View v, MotionEvent event) {

try {

Activity activity = getActivity();

CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE);

CameraCharacteristics characteristics = manager.getCameraCharacteristics(mCameraId);

float maxzoom = (characteristics.get(CameraCharacteristics.SCALER_AVAILABLE_MAX_DIGITAL_ZOOM))*10;

Rect m = characteristics.get(CameraCharacteristics.SENSOR_INFO_ACTIVE_ARRAY_SIZE);

int action = event.getAction();

float current_finger_spacing;

if (event.getPointerCount() > 1) {

// Multi touch logic

current_finger_spacing = getFingerSpacing(event);

if(finger_spacing != 0){

if(current_finger_spacing > finger_spacing && maxzoom > zoom_level){

zoom_level++;

} else if (current_finger_spacing < finger_spacing && zoom_level > 1){

zoom_level--;

}

int minW = (int) (m.width() / maxzoom);

int minH = (int) (m.height() / maxzoom);

int difW = m.width() - minW;

int difH = m.height() - minH;

int cropW = difW /100 *(int)zoom_level;

int cropH = difH /100 *(int)zoom_level;

cropW -= cropW & 3;

cropH -= cropH & 3;

Rect zoom = new Rect(cropW, cropH, m.width() - cropW, m.height() - cropH);

mPreviewRequestBuilder.set(CaptureRequest.SCALER_CROP_REGION, zoom);

}

finger_spacing = current_finger_spacing;

} else{

if (action == MotionEvent.ACTION_UP) {

//single touch logic

}

}

try {

mCaptureSession

.setRepeatingRequest(mPreviewRequestBuilder.build(), mCaptureCallback, null);

} catch (CameraAccessException e) {

e.printStackTrace();

} catch (NullPointerException ex) {

ex.printStackTrace();

}

} catch (CameraAccessException e) {

throw new RuntimeException("can not access camera.", e);

}

return true;

}

//Determine the space between the first two fingers

@SuppressWarnings("deprecation")

private float getFingerSpacing(MotionEvent event) {

float x = event.getX(0) - event.getX(1);

float y = event.getY(0) - event.getY(1);

return (float) Math.sqrt(x * x + y * y);

}