将真实图像坐标转换为宽高比？答案

【问题标题】：Convert real image coordinates to aspect fit?将真实图像坐标转换为宽高比？
【发布时间】：2018-06-28 06:43:24
【问题描述】：

例如：用户选择 1000 * 1000 图像我发送到后端以检测对象，因此我正在获取图像中存在的对象的坐标。

Like this :(
                {
            x = 385;
            y = 249;
        },
                {
            x = 448;
            y = 242;
        },
                {
            x = 454;
            y = 276;
        },
                {
            x = 391;
            y = 284;
        }
    );

我将图像视图设置为宽高比，因此图像的实际大小会有所不同，因此我需要根据宽高比匹配大小更改坐标以适应宽高比匹配大小的图像。

这是我尝试过的代码。

var topLeftXOne = point[0]["x"] as! CGFloat
var topLeftYOne = point[0]["y"] as! CGFloat
var topRightXOne = point[1]["x"] as! CGFloat
var topRightYOne = point[1]["y"] as! CGFloat
var bottomtopRightXOne = point[2]["x"] as! CGFloat
var bottomRightYOne = point[2]["y"] as! CGFloat
                            
 var bottomLeftXOne = point[3]["x"] as! CGFloat
 var bottomLeftYOne = point[3]["y"] as! CGFloat
    
  let pointsView = ALPDView(frame: CGRect.zero)
  let x: CGRect = AVMakeRect(aspectRatio: image.size, insideRect: pointsView.imageView.frame)
    
 let scaleX = image.size.width / x.width
 let scaleY = image.size.height / x.height
                            
 topLeftXOne = topLeftXOne / scaleX
 topLeftYOne = topLeftYOne / scaleY
                            
 topRightXOne = topRightXOne / scaleX
 topRightYOne = topRightYOne / scaleY
                            
 bottomtopRightXOne = bottomtopRightXOne / scaleX
 bottomRightYOne = bottomRightYOne / scaleY
                            
 bottomLeftXOne = bottomLeftXOne / scaleX
 bottomLeftYOne = bottomLeftYOne / scaleY

但我没有得到正确的结果。

这个例如image ，我想更改坐标以适应宽高比图像大小。

【问题讨论】：

标签： ios swift uiimage uibezierpath cgpoint

【解决方案1】：

最后我通过使用 ratio 方法实现了这一点。我取了图像大小的纵横比，并根据比率数学计算。

让 x: CGRect = AVMakeRect(aspectRatio: image.size, insideRect: pointsView.imageView.frame)

让 scaleX = image.size.width / x.width

让 scaleY = image.size.height / x.height

                        var topLeftXOne = point[0]["x"] as! CGFloat
                        var topLeftYOne = point[0]["y"] as! CGFloat

                        var topRightXOne = point[1]["x"] as! CGFloat
                        var topRightYOne = point[1]["y"] as! CGFloat

                        var bottomtopRightXOne = point[2]["x"] as! CGFloat
                        var bottomRightYOne = point[2]["y"] as! CGFloat

                        var bottomLeftXOne = point[3]["x"] as! CGFloat
                        var bottomLeftYOne = point[3]["y"] as! CGFloat

                        let pointsView = ALPDView(frame: CGRect.init(x: 0, y: 0, width:self.view.frame.size.width , height: self.view.frame.size.height))

                        let additionValueForX = x.origin.x + 20
                        let additionValueForY = x.origin.y - 40

                        topLeftXOne = topLeftXOne / scaleX + additionValueForX
                        topLeftYOne = topLeftYOne / scaleY + additionValueForY

                        topRightXOne = topRightXOne / scaleX + additionValueForX
                        topRightYOne = topRightYOne / scaleY + additionValueForY

                        bottomtopRightXOne = bottomtopRightXOne / scaleX + additionValueForX
                        bottomRightYOne = bottomRightYOne / scaleY + additionValueForY

                        bottomLeftXOne = bottomLeftXOne / scaleX + additionValueForX
                        bottomLeftYOne = bottomLeftYOne / scaleY + additionValueForY

【讨论】：