How to set a starting point using path () in onDraw () using canvas..?

I am making a app like Drive axle for Auto crop selected Path () using Paint () and then i make a this screen..

But my Problem is that my starting point start with 0 position TOP_LEFT_CORNER X AND Y AXIS

USING this x and y coordinates i make a this type of rectangle but i need this type of out put using this coordinates..

{"TOP_LEFT_X_AXIS":" 43", "TOP_LEFT_y_AXIS":" 278",

"TOP_RIGHT_X_AXIS":"532", "TOP_RIGHT_y_AXIS":" 300 "}}

"BOTTOM_RIGHT_X_AXIS":"510", "BOTTOM_RIGHT_y_AXIS":" 614",

"BOTTOM_LEFT_X_AXIS":" 45", "BOTTOM_LEFT_Y_AXIS":" 597",

Need this type of Out Put see this image..

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    path = new Path();

    path.lineTo(x1, y1);
    path.lineTo(x2, y2);
    path.lineTo(x3, y3);
    path.lineTo(x4, y4);
    canvas.drawPath(path, currentPaint);

}

Edit :- 1-1-2014

Now i make rectangle successfully now i want to crop that part of images and set on another image view any idea about this..

Edit :- 1-07-2014

Now i want to draw a circle at corner tell me if you have any idea..