ios 如何在椭圆形或圆形上裁剪 UIImage？
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How to crop UIImage on oval shape or circle shape?
提问by ram
Please give ideas for how to crop UIImageon oval shape or circle shape. Please share your ideas.
请给出有关如何裁剪UIImage椭圆形或圆形的想法。请分享您的想法。
回答by Rakesh Bhatt
#import <QuartzCore/QuartzCore.h>
CALayer *imageLayer = YourImageview.layer;
[imageLayer setCornerRadius:5];
[imageLayer setBorderWidth:1];
[imageLayer setMasksToBounds:YES];
by increasing radius it will become more round-able.
通过增加半径，它将变得更圆。
As long as the image is a square, you can get a perfect circle by taking half the width as the corner radius:
只要图像是正方形，就可以用一半的宽度作为角半径得到一个完美的圆：
[imageView.layer setCornerRadius:imageView.frame.size.width/2];
You also need to add
您还需要添加
[imageView.layer setMasksToBounds:YES];
Swift 4.2
斯威夫特 4.2
import QuartzCore
var imageLayer: CALayer? = YourImageview.layer
imageLayer?.cornerRadius = 5
imageLayer?.borderWidth = 1
imageLayer?.masksToBounds = true
回答by Chris Nelson
I started looking into this a couple of weeks back. I tried all the suggestions here, none of which worked well. In the great tradition of RTFM I went and read Apple's documentation on Quartz 2D Programmingand came up with this. Please try it out and let me know how you go.
几周前我开始研究这个。我尝试了这里的所有建议，但没有一个效果很好。在 RTFM 的伟大传统中，我去阅读了 Apple 关于Quartz 2D Programming的文档并提出了这个。请尝试一下，让我知道您的进展情况。
The code could be fairly easily altered to crop to an elipse, or any other shape defined by a path.
可以很容易地修改代码以裁剪为椭圆形或由路径定义的任何其他形状。
Make sure you include Quartz 2D in your project.
确保在项目中包含 Quartz 2D。
#include <math.h>
+ (UIImage*)circularScaleAndCropImage:(UIImage*)image frame:(CGRect)frame {
// This function returns a newImage, based on image, that has been:
// - scaled to fit in (CGRect) rect
// - and cropped within a circle of radius: rectWidth/2
//Create the bitmap graphics context
UIGraphicsBeginImageContextWithOptions(CGSizeMake(frame.size.width, frame.size.height), NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
//Get the width and heights
CGFloat imageWidth = image.size.width;
CGFloat imageHeight = image.size.height;
CGFloat rectWidth = frame.size.width;
CGFloat rectHeight = frame.size.height;
//Calculate the scale factor
CGFloat scaleFactorX = rectWidth/imageWidth;
CGFloat scaleFactorY = rectHeight/imageHeight;
//Calculate the centre of the circle
CGFloat imageCentreX = rectWidth/2;
CGFloat imageCentreY = rectHeight/2;
// Create and CLIP to a CIRCULAR Path
// (This could be replaced with any closed path if you want a different shaped clip)
CGFloat radius = rectWidth/2;
CGContextBeginPath (context);
CGContextAddArc (context, imageCentreX, imageCentreY, radius, 0, 2*M_PI, 0);
CGContextClosePath (context);
CGContextClip (context);
//Set the SCALE factor for the graphics context
//All future draw calls will be scaled by this factor
CGContextScaleCTM (context, scaleFactorX, scaleFactorY);
// Draw the IMAGE
CGRect myRect = CGRectMake(0, 0, imageWidth, imageHeight);
[image drawInRect:myRect];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
Include the following code in your UIView class replacing "monk2.png" with your own image name.
在 UIView 类中包含以下代码，用您自己的图像名称替换“monk2.png”。
- (void)drawRect:(CGRect)rect {
UIImage *originalImage = [UIImage imageNamed:[NSString stringWithFormat:@"monk2.png"]];
CGFloat oImageWidth = originalImage.size.width;
CGFloat oImageHeight = originalImage.size.height;
// Draw the original image at the origin
CGRect oRect = CGRectMake(0, 0, oImageWidth, oImageHeight);
[originalImage drawInRect:oRect];
// Set the newRect to half the size of the original image
CGRect newRect = CGRectMake(0, 0, oImageWidth/2, oImageHeight/2);
UIImage *newImage = [self circularScaleAndCropImage:originalImage frame:newRect];
CGFloat nImageWidth = newImage.size.width;
CGFloat nImageHeight = newImage.size.height;
//Draw the scaled and cropped image
CGRect thisRect = CGRectMake(oImageWidth+10, 0, nImageWidth, nImageHeight);
[newImage drawInRect:thisRect];
}
回答by Mohammad Sadiq
To have imageView in oval shape is not difficult.
将 imageView 设为椭圆形并不困难。
You can do the following
您可以执行以下操作
UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:yourImageView.bounds];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.path = path.CGPath;
yourImageView.layer.mask = maskLayer;
If the rect passed to bezierPathWithOvalInRect is Square the image will be cropped to circle.
如果传递给 bezierPathWithOvalInRect 的 rect 是 Square，则图像将被裁剪为圆形。
Swift Code
SWIFT代码
let path = UIBezierPath(ovalIn: yourImageView.bounds)
let maskLayer = CAShapeLayer()
maskLayer.path = path.cgPath
yourImageView.layer.mask = maskLayer
回答by pkc456
SWIFT
迅速
var vwImage = UIImageView(image: UIImage(named: "Btn_PinIt_Normal.png"))
vwImage.frame = CGRectMake(0, 0, 100, 100)
vwImage.layer.cornerRadius = vwImage.frame.size.width/2
回答by Dilip Rajkumar
After a long search I found the correct way to circle the image
经过长时间的搜索，我找到了圈出图像的正确方法
Download the Support archive file from URL http://vocaro.com/trevor/blog/2009/10/12/resize-a-uiimage-the-right-way/
从 URL http://vocaro.com/trevor/blog/2009/10/12/resize-a-uiimage-the-right-way/下载支持存档文件
#import "UIImage+RoundedCorner.h"
#import "UIImage+Resize.h"
Following lines used to resize the image and convert in to round with radius
以下几行用于调整图像大小并转换为具有半径的圆形
UIImage *mask = [UIImage imageNamed:@"mask.jpg"];
mask = [mask resizedImage:CGSizeMake(47, 47) interpolationQuality:kCGInterpolationHigh ];
mask = [mask roundedCornerImage:23.5 borderSize:1];
回答by Hardik Thakkar
To make a RoundShape Image
制作圆形图像
Step1: in .h file
步骤 1：在 .h 文件中
@property (strong, nonatomic) IBOutlet UIImageView *songImage;
Step2: in .m file
步骤 2：在 .m 文件中
- (void)viewDidLoad
{
self.songImage.layer.cornerRadius = self.songImage.frame.size.width / 2;
self.songImage.clipsToBounds = YES;
//To give the Border and Border color of imageview
self.songImage.layer.borderWidth = 1.0f;
self.songImage.layer.borderColor = [UIColor colorWithRed:249/255.0f green:117/255.0f blue:44/255.0f alpha:1.0f].CGColor;
}
OR For Swift
或 Swift
cell.songImage.layer.cornerRadius = cell.songImage.frame.size.width / 2;
cell.songImage.clipsToBounds = true
//To give the Border and Border color of imageview
cell.songImage.layer.borderWidth = 1.0
cell.songImage.layer.borderColor = UIColor(red: 50.0/255, green: 150.0/255, blue: 65.0/255, alpha: 1.0).CGColor
回答by codeburn
If you only need a perfect circle, changing the shape of the UIImageView could help. Simply add the QuartzCore framework to your project and add these lines of code somewhere in the lifecycle before the imageView is displayed:
如果你只需要一个完美的圆，改变 UIImageView 的形状会有所帮助。只需将 QuartzCore 框架添加到您的项目中，并在显示 imageView 之前在生命周期的某处添加这些代码行：
#import <QuartzCore/QuartzCore.h>
.
.
.
//to crop your UIImageView to show only a circle
yourImageView.layer.cornerRadius = yourImageView.frame.size.width/2;
yourImageView.clipsToBounds = YES;
回答by EFC
Check out CGImageCreateWithMask. Create a mask of your oval shape, then apply it to the image.
退房CGImageCreateWithMask。创建椭圆形的蒙版，然后将其应用于图像。
回答by Maulik
you should refer This...
你应该参考这个...
// Create the image from a png file
UIImage *image = [UIImage imageNamed:@"prgBinary.jpg"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
// Get size of current image
CGSize size = [image size];
// Frame location in view to show original image
[imageView setFrame:CGRectMake(0, 0, size.width, size.height)];
[[self view] addSubview:imageView];
[imageView release];
// Create rectangle that represents a cropped image
// from the middle of the existing image
CGRect rect = CGRectMake(size.width / 4, size.height / 4 ,
(size.width / 2), (size.height / 2)); //oval logic goes here
// Create bitmap image from original image data,
// using rectangle to specify desired crop area
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], rect);
UIImage *img = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
// Create and show the new image from bitmap data
imageView = [[UIImageView alloc] initWithImage:img];
[imageView setFrame:CGRectMake(0, 200, (size.width / 2), (size.height / 2))];
[[self view] addSubview:imageView];
[imageView release];
回答by Jerome
SWIFT 3answer comes from @Mohammad Sadiq
SWIFT 3答案来自@Mohammad Sadiq
let path = UIBezierPath.init(ovalIn: workingImgaeView.bounds)
let maskLayer = CAShapeLayer(layer: layer)
maskLayer.path = path.cgPath
workingImgaeView.layer.mask = maskLayer
