我正在使用以下代码在 android 中执行图像裁剪。
但我得到了错误的结果。我得到了非常缩放的图片，我认为我的代码有问题
代码：
package net.londatiga.android;
import java.io.ByteArrayOutputStream;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Point;
import android.graphics.PointF;
import android.graphics.drawable.BitmapDrawable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.ImageView;
public class CropView extends ImageView {
Paint paint = new Paint();
private int initial_size = 300;
private static Point leftTop, rightBottom, center, previous;
private static final int DRAG= 0;
private static final int LEFT= 1;
private static final int TOP= 2;
private static final int RIGHT= 3;
private static final int BOTTOM= 4;
private int imageScaledWidth,imageScaledHeight;
// Adding parent class constructors
public CropView(Context context) {
super(context);
initCropView();
}
public CropView(Context context, AttributeSet attrs) {
super(context, attrs, 0);
initCropView();
}
public CropView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initCropView();
}
@Override
protected void onDraw(Canvas canvas)
{
super.onDraw(canvas);
if(leftTop.equals(0, 0))
resetPoints();
canvas.drawRect(leftTop.x, leftTop.y, rightBottom.x, rightBottom.y, paint);
}
@Override
public boolean onTouchEvent(MotionEvent event) {
int eventaction = event.getAction();
switch (eventaction) {
case MotionEvent.ACTION_DOWN:
previous.set((int)event.getX(), (int)event.getY());
break;
case MotionEvent.ACTION_MOVE:
if(isActionInsideRectangle(event.getX(), event.getY())) {
adjustRectangle((int)event.getX(), (int)event.getY());
invalidate(); // redraw rectangle
previous.set((int)event.getX(), (int)event.getY());
}
break;
case MotionEvent.ACTION_UP:
previous = new Point();
break;
}
return true;
}
private void initCropView() {
paint.setColor(Color.YELLOW);
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(5);
leftTop = new Point();
rightBottom = new Point();
center = new Point();
previous = new Point();
}
public void resetPoints() {
center.set(getWidth()/2, getHeight()/2);
leftTop.set((getWidth()-initial_size)/2,(getHeight()-initial_size)/2);
rightBottom.set(leftTop.x+initial_size, leftTop.y+initial_size);
}
private static boolean isActionInsideRectangle(float x, float y) {
int buffer = 10;
return (x>=(leftTop.x-buffer)&&x<=(rightBottom.x+buffer)&& y>=(leftTop.y-buffer)&&y<=(rightBottom.y+buffer))?true:false;
}
private boolean isInImageRange(PointF point) {
// Get image matrix values and place them in an array
float[] f = new float[9];
getImageMatrix().getValues(f);
// Calculate the scaled dimensions
imageScaledWidth = Math.round(getDrawable().getIntrinsicWidth() * f[Matrix.MSCALE_X]);
imageScaledHeight = Math.round(getDrawable().getIntrinsicHeight() * f[Matrix.MSCALE_Y]);
return (point.x>=(center.x-(imageScaledWidth/2))&&point.x<=(center.x+(imageScaledWidth/2))&&point.y>=(center.y-(imageScaledHeight/2))&&point.y<=(center.y+(imageScaledHeight/2)))?true:false;
}
private void adjustRectangle(int x, int y) {
int movement;
switch(getAffectedSide(x,y)) {
case LEFT:
movement = x-leftTop.x;
if(isInImageRange(new PointF(leftTop.x+movement,leftTop.y+movement)))
leftTop.set(leftTop.x+movement,leftTop.y+movement);
break;
case TOP:
movement = y-leftTop.y;
if(isInImageRange(new PointF(leftTop.x+movement,leftTop.y+movement)))
leftTop.set(leftTop.x+movement,leftTop.y+movement);
break;
case RIGHT:
movement = x-rightBottom.x;
if(isInImageRange(new PointF(rightBottom.x+movement,rightBottom.y+movement)))
rightBottom.set(rightBottom.x+movement,rightBottom.y+movement);
break;
case BOTTOM:
movement = y-rightBottom.y;
if(isInImageRange(new PointF(rightBottom.x+movement,rightBottom.y+movement)))
rightBottom.set(rightBottom.x+movement,rightBottom.y+movement);
break;
case DRAG:
movement = x-previous.x;
int movementY = y-previous.y;
if(isInImageRange(new PointF(leftTop.x+movement,leftTop.y+movementY)) && isInImageRange(new PointF(rightBottom.x+movement,rightBottom.y+movementY))) {
leftTop.set(leftTop.x+movement,leftTop.y+movementY);
rightBottom.set(rightBottom.x+movement,rightBottom.y+movementY);
}
break;
}
}
private static int getAffectedSide(float x, float y) {
int buffer = 10;
if(x>=(leftTop.x-buffer)&&x<=(leftTop.x+buffer))
return LEFT;
else if(y>=(leftTop.y-buffer)&&y<=(leftTop.y+buffer))
return TOP;
else if(x>=(rightBottom.x-buffer)&&x<=(rightBottom.x+buffer))
return RIGHT;
else if(y>=(rightBottom.y-buffer)&&y<=(rightBottom.y+buffer))
return BOTTOM;
else
return DRAG;
}
public byte[] getCroppedImage() {
BitmapDrawable drawable = (BitmapDrawable)getDrawable();
float x = leftTop.x-center.x+(drawable.getBitmap().getWidth()/2);
float y = leftTop.y-center.y+(drawable.getBitmap().getHeight()/2);
Bitmap cropped = Bitmap.createBitmap(drawable.getBitmap(),(int)x,(int)y,(int)rightBottom.x-(int)leftTop.x,(int)rightBottom.y-(int)leftTop.y);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
cropped.compress(Bitmap.CompressFormat.PNG, 100, stream);
return stream.toByteArray();
}
}
我尝试裁剪的图像是
预期的图像是矩形框中的内容，但我得到了非常放大的图像
结果图像
我该如何解决这个问题，我尝试通过更改一些代码但没有找到任何结果。
另一个问题是，通过使用这个矩形框，我只能以矩形形状裁剪图像，是否有可能以我想要的任何形状裁剪图像。
我在其中一个应用程序（文档扫描仪跟踪版本）中观察到了这一点，其中用户可以使用相同的矩形框以某些不规则形状裁剪图像。
我怎样才能达到这个结果？
请建议
谢谢