ios – 用UIBezierPath – Swift表示CIRectangleFeature

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目前我正在使用CIDetector来检测我的UI Image中的矩形.我正在做一个建议的方式,你将坐标传递给一个过滤器,以获取一个CIImage来放弃所占用的UIImage.看起来像这样:
func performRectangleDetection(image: UIKit.CIImage) -> UIKit.CIImage? {
    var resultImage: UIKit.CIImage?
    let detector:CIDetector = CIDetector(ofType: CIDetectorTypeRectangle,context: nil,options: [CIDetectorAccuracy : CIDetectorAccuracyHigh])
        // Get the detections
        let features = detector.featuresInImage(image)
        for feature in features as! [CIRectangleFeature] {
            resultImage = self.drawHighlightOverlayForPoints(image,topLeft: feature.topLeft,topRight: feature.topRight,bottomLeft: feature.bottomLeft,bottomRight: feature.bottomRight)
        }
    return resultImage

}


func drawHighlightOverlayForPoints(image: UIKit.CIImage,topLeft: CGPoint,topRight: CGPoint,bottomLeft: CGPoint,bottomRight: CGPoint) -> UIKit.CIImage {

    var overlay = UIKit.CIImage(color: CIColor(red: 1.0,green: 0.55,blue: 0.0,alpha: 0.45))
    overlay = overlay.imageByCroppingToRect(image.extent)
    overlay = overlay.imageByApplyingFilter("CIPerspectiveTransformWithExtent",withInputParameters: [
                                                "inputExtent": CIVector(CGRect: image.extent),"inputTopLeft": CIVector(CGPoint: topLeft),"inputTopRight": CIVector(CGPoint: topRight),"inputBottomLeft": CIVector(CGPoint: bottomLeft),"inputBottomRight": CIVector(CGPoint: bottomRight)
        ])
    return overlay.imageByCompositingOverImage(image)
}

调用performRectangleDetection通过CIImage显示检测到的矩形.

它看起来像上图.我需要使用设置为笔画的UIBezierPath显示相同的红色矩形.我需要这样做,所以用户可以调整检测,以防它不是100%准确.我试图画出一条路,但是一直没有成功.这是我如何绘制路径.我使用一个叫做rect的自定义类来保存4点.这是检测:

func detectRect() -> Rect{
    var rect:Rect?
    let detector:CIDetector = CIDetector(ofType: CIDetectorTypeRectangle,options: [CIDetectorAccuracy : CIDetectorAccuracyHigh])
    // Get the detections
    let features = detector.featuresInImage(UIKit.CIImage(image: self)!)
    for feature in features as! [CIRectangleFeature] {
        rect = Rect(tL: feature.topLeft,tR: feature.topRight,bR: feature.bottomRight,bL: feature.bottomLeft)
    }
    return rect!
}

接下来,我必须缩放坐标.这是Rect类里面的函数

func scaleRect(image:UIImage,imageView:UIImageView) ->Rect{

    let scaleX = imageView.bounds.width/image.size.width
    var tlx = topLeft.x * scaleX
    var tly = topLeft.y * scaleX
    tlx += (imageView.bounds.width - image.size.width * scaleX) / 2.0
    tly += (imageView.bounds.height - image.size.height * scaleX) / 2.0
    let tl = CGPointMake(tlx,tly)

    var trx = topRight.x * scaleX
    var trY = topRight.y * scaleX
    trx += (imageView.bounds.width - image.size.width * scaleX) / 2.0
    trY += (imageView.bounds.height - image.size.height * scaleX) / 2.0
    let tr = CGPointMake(trx,trY)

    var brx = bottomRight.x * scaleX
    var bry = bottomRight.y * scaleX
    brx += (imageView.bounds.width - image.size.width * scaleX) / 2.0
    bry += (imageView.bounds.height - image.size.height * scaleX) / 2.0
    let br = CGPointMake(brx,bry)

    var blx = bottomLeft.x * scaleX
    var bly = bottomLeft.y * scaleX
    blx += (imageView.bounds.width - image.size.width * scaleX) / 2.0
    bly += (imageView.bounds.height - image.size.height * scaleX) / 2.0
    let bl = CGPointMake(blx,bly)

    let rect = Rect(tL: tl,tR: tr,bR: br,bL: bl)
    return rect
}

最后我画的路径:

var tet = image.detectRect()
tet = tet.scaleRect(image,imageView: imageView)
let shapeLayer = CAShapeLayer()
let path = ViewController.drawPath(tet.topLeft,p2: tet.topRight,p3: tet.bottomRight,p4: tet.bottomLeft)
shapeLayer.path = path.CGPath
shapeLayer.lineWidth = 5
shapeLayer.fillColor = nil
shapeLayer.strokeColor = UIColor.orangeColor().CGColor
imageView.layer.addSublayer(shapeLayer)

路径已经离开屏幕并且不准确.我知道我必须将坐标从CoreImage坐标调整到UIKit坐标,然后将其缩放为UIImageView.不幸的是,我不知道该怎么做.我知道我可以重用我的一些检测代码来完成这个,但我不知道正确的步骤.任何帮助将不胜感激!谢谢.这是发生的一个例子:

更新

为了测试我在scaleRect()中执行的缩放比例,我决定使我的ImageView大小与我的图像大小相同.然后我打印了缩放之前和之后的坐标.我会认为,因为它们是一样的,我的缩放是正确的.这是代码

var tet = image.detectRect()
//Before scaling
print(tet.topLeft)
print(tet.topRight)
print(tet.bottomRight)
print(tet.bottomLeft)
print("**************************************************")
//After scaling
tet = tet.scaleRect(image,imageView: imageView)
print(tet.topLeft)
print(tet.topRight)
print(tet.bottomRight)
print(tet.bottomLeft)

这是输出

(742.386596679688,927.240844726562)

(1514.93835449219,994.811096191406)

(1514.29675292969,155.2802734375)

(741.837524414062,208.55403137207)

(742.386596679688,208.55403137207)

更新

为了尝试和缩放我的坐标,我再尝试了两件事情.

1号:
我已经尝试使用UIView convertPoint函数,以将点从图像转换为UIImageView.这是我如何编码:
我用scaleRect()函数替换

let view_image = UIView(frame: CGRectMake(0,image.size.width,image.size.height))
let tL = view_image.convertPoint(self.topLeft,toView: imageView)
let tR = view_image.convertPoint(self.topRight,toView: imageView)
let bR = view_image.convertPoint(self.bottomRight,toView: imageView)
let bL = view_image.convertPoint(self.bottomLeft,toView: imageView)

然后,我回到了这一点.

2号:
我根据图像和imageView的宽度和高度的差异,尝试了简单的坐标转换.代理代码

let widthDiff = (image.size.width - imageView.frame.size.width)
 let highDiff = (image.size.height - imageView.frame.size.height)

 let tL = CGPointMake(self.topLeft.x-widthDiff,self.topLeft.y-highDiff)
 let tR = CGPointMake(self.topRight.x-widthDiff,self.topRight.y-highDiff)
 let bR = CGPointMake(self.bottomRight.x-widthDiff,self.bottomRight.y-highDiff)
 let bL = CGPointMake(self.bottomLeft.x-widthDiff,self.bottomLeft.y-highDiff)

更新
我也试过使用CGAffineTransform.码:

var transform = CGAffineTransformMakeScale(1,-1)
transform = CGAffineTransformTranslate(transform,-imageView.bounds.size.height)
let tL = CGPointApplyAffineTransform(self.topLeft,transform)
let tR = CGPointApplyAffineTransform(self.topRight,transform)
let bR = CGPointApplyAffineTransform(self.bottomRight,transform)
let bL = CGPointApplyAffineTransform(self.bottomLeft,transform)

没有工作我不知道还有什么可以尝试的.请帮忙.这将不胜感激.谢谢!

解决方法

我一直在努力解决同样的问题几天,这就是我如何克服这个问题:

我做了一个自定义类来存储点并添加一些帮助函数

//
//  ObyRectangleFeature.swift
//
//  Created by 4oby on 5/20/16.
//  Copyright © 2016 cvv. All rights reserved.
//

import Foundation
import UIKit

extension CGPoint {
    func scalePointByCeficient(ƒ_x: CGFloat,ƒ_y: CGFloat) -> CGPoint {
        return CGPoint(x: self.x/ƒ_x,y: self.y/ƒ_y) //original image
    }

    func reversePointCoordinates() -> CGPoint {
        return CGPoint(x: self.y,y: self.x)
    }

    func sumPointCoordinates(add: CGPoint) -> CGPoint {
        return CGPoint(x: self.x + add.x,y: self.y + add.y)
    }

    func substractPointCoordinates(sub: CGPoint) -> CGPoint {
        return CGPoint(x: self.x - sub.x,y: self.y - sub.y)
    }
}

class ObyRectangleFeature : NSObject {

    var topLeft: CGPoint!
    var topRight: CGPoint!
    var bottomLeft: CGPoint!
    var bottomRight: CGPoint!

    var centerPoint : CGPoint{
        get {
            let centerX = ((topLeft.x + bottomLeft.x)/2 + (topRight.x + bottomRight.x)/2)/2
            let centerY = ((topRight.y + topLeft.y)/2 + (bottomRight.y + bottomLeft.y)/2)/2
            return CGPoint(x: centerX,y: centerY)
        }

    }

    convenience init(_ rectangleFeature: CIRectangleFeature) {
        self.init()
        topLeft = rectangleFeature.topLeft
        topRight = rectangleFeature.topRight
        bottomLeft = rectangleFeature.bottomLeft
        bottomRight = rectangleFeature.bottomRight
    }

    override init() {
        super.init()
    }


    func rotate90Degree() -> Void {

        let centerPoint =  self.centerPoint

//        /rotate cos(90)=0,sin(90)=1
        topLeft = CGPoint(x: centerPoint.x + (topLeft.y - centerPoint.y),y: centerPoint.y + (topLeft.x - centerPoint.x))
        topRight = CGPoint(x: centerPoint.x + (topRight.y - centerPoint.y),y: centerPoint.y + (topRight.x - centerPoint.x))
        bottomLeft = CGPoint(x: centerPoint.x + (bottomLeft.y - centerPoint.y),y: centerPoint.y + (bottomLeft.x - centerPoint.x))
        bottomRight = CGPoint(x: centerPoint.x + (bottomRight.y - centerPoint.y),y: centerPoint.y + (bottomRight.x - centerPoint.x))
    }

    func  scaleRectWithCoeficient(ƒ_x: CGFloat,ƒ_y: CGFloat) -> Void {
        topLeft =  topLeft.scalePointByCeficient(ƒ_x,ƒ_y: ƒ_y)
        topRight = topRight.scalePointByCeficient(ƒ_x,ƒ_y: ƒ_y)
        bottomLeft = bottomLeft.scalePointByCeficient(ƒ_x,ƒ_y: ƒ_y)
        bottomRight = bottomRight.scalePointByCeficient(ƒ_x,ƒ_y: ƒ_y)
    }

    func correctOriginPoints() -> Void {

        let deltaCenter = self.centerPoint.reversePointCoordinates().substractPointCoordinates(self.centerPoint)

        let TL = topLeft
        let TR = topRight
        let BL = bottomLeft
        let BR = bottomRight

        topLeft = BL.sumPointCoordinates(deltaCenter)
        topRight = TL.sumPointCoordinates(deltaCenter)
        bottomLeft = BR.sumPointCoordinates(deltaCenter)
        bottomRight = TR.sumPointCoordinates(deltaCenter)
    }
}

这是初始化代码

let scalatedRect : ObyRectangleFeature = ObyRectangleFeature(rectangleFeature)
        // fromSize -> Initial size of the CIImage
        // toSize -> the size of the scaled Image
        let ƒ_x = (fromSize.width/toSize.width)
        let ƒ_y = (fromSize.height/toSize.height)

        /*the coeficients are interchange intentionally cause of the different
        coordinate system used by CIImage and UIImage,you could rotate before 
        scaling,to preserve the order,but if you do,the result will be offCenter*/

        scalatedRect.scaleRectWithCoeficient(ƒ_y,ƒ_y: ƒ_x)
        scalatedRect.rotate90Degree()
        scalatedRect.correctOriginPoints()

在这一点上,ScaleRect已经准备好以任何你喜欢的方式绘制.

原文链接:https://www.f2er.com/iOS/336948.html

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