java – ImageView坐标与位图像素之间的对应关系 – Android

在我的应用程序中,我希望用户能够选择 ImageView中包含的图像的某些内容.

要选择内容,我将ImageView类子化,使其实现OnTouchListener,以便绘制一个带有用户决定的边框的矩形.

这是一个绘图结果的例子(有一个想法,如何工作,你可以想到它,当你点击鼠标在桌面上拖动鼠标)：

现在我需要确定位图图像的哪些像素对应于所选的部分.这是很容易确定哪些是ImageView属于矩形的点,但我不知道如何获取通信像素,因为ImageView具有不同于原始图像的长宽比.

我遵循了描述especially here,but also here的方法,但我不完全满意,因为在我看来,ImageView上的对应关系是像素和点之间的1比1,并且不会将原始图像上的所有相应像素给出到所选区域.

调用hovedRectViewViewView上的矩形是：

class Point {
    float x,y;
    @Override
    public String toString() {
        return x + "," + y;
    }
}

Vector<Point> pointsInRect = new Vector<Point>();

for( int x = hoveredRect.left; x <= hoveredRect.right; x++ ){
    for( int y = hoveredRect.top; y <= hoveredRect.bottom; y++ ){

        Point pointInRect = new Point();
        pointInRect.x = x;
        pointInRect.y = y;
        pointsInRect.add(pointInRect);
    }   
}

如何获取矢量<像素> pixelInImage包含Bitmap图像的相应像素？

补充说明

我会解释一下我的问题的上下文：

I need to do some image processing on the selected part,and want to
be sure that all the pixels in the rectangle get processed.

The image processing will be done on a server but it needs to know exactly which
pixels to process. Server works with image with real dimensions,
android app just tells which pixels to process to the server by passing a vector
containing the pixel coordinates

为什么我不喜欢上述链接中提出的解决方案：

The answers given transform coordinates with a 1 to 1 fashion. This approach clearly is
not valid for my task,since an area of say 50 points in the ImageView of a certain
size on the screen cannot correspond to an area of the same number of pixels in the real
image,but should consider the different aspect ratio.

例如,如果图像小于应用程序上显示的ImageView,则应选择该区域：

ImageViewWidth = 400,ImageViewHeight = 150
BitmapWidth = 176,BitmapHeight = 65

WidthRatio = BitmapWidth / ImageViewWidth = 175 / 400 = 0.44
HeightRatio = BitmapHeight / ImageViewHeight = 65 / 150 = 0.44

BitmapPixelX = ImageViewPixelX * WidthRatio
BitmapPixelY = ImageViewPixelY * HeightRatio

RectTopLeftX = 271,RectTopLeftY = 19
RectBottomRightX = 313,RectBottomRightY = 42

RectTopLeftX * WidthRatio = 271 * .44 = 119.24
RectTopLeftY * HeightRatio = 19 * .44 = 8.36