iOS – 合并两个不同大小的图像
我面临以下问题：我必须合并两个图像A和B，以创build一个新的图像C作为合并的结果。
我已经知道如何合并两个图像，但在这种情况下，我的目标有点不同。
我想这个图像A将是图像B的背景。
例如，如果图片A的大小是500×500，图片B的大小是460×460，我希望图片C（合并图片的结果）将是500×500，图片B（460×460）居中。
提前感谢您的帮助或build议
这是我在我的应用程序，但没有使用UIImageView ：
UIImage *bottomImage = [UIImage imageNamed:@"bottom.png"]; //background image UIImage *image = [UIImage imageNamed:@"top.png"]; //foreground image CGSize newSize = CGSizeMake(width, height); UIGraphicsBeginImageContext( newSize ); // Use existing opacity as is [bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)]; // Apply supplied opacity if applicable [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.8]; UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext();
如果图像已经具有不透明性，则不需要设置（如在bottomImage中），否则可以将其设置（如图像）。
在创build这个UIImage之后，你可以把它embedded到你的UIImageView
更新 ：感谢艾哈迈德AkkoK – 为Swift（2.2）用户混合模式macros已经改变。 CGBlendMode .kCGBlendModeNormal被replace为CGBlendMode.Normal
嘿，我有多个图像添加不同的前景相同的背景这是我的代码
UIImage *bottomImage = [UIImage imageNamed:@"photo 2.JPG"]; //background image UIImage *image = [UIImage imageNamed:@"photo 3.JPG"]; //foreground image UIImage *image1 = [UIImage imageNamed:@"photo 4.JPG"]; //foreground image UIImage *image2 = [UIImage imageNamed:@"photo 5.JPG"]; //foreground image CGSize newSize = CGSizeMake(320, 480); UIGraphicsBeginImageContext( newSize ); // Use existing opacity as is [bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)]; // Apply supplied opacity if applicable [image drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.4]; [image1 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.3]; [image2 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.2]; UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); resultView = [[UIImageView alloc] initWithImage:newImage]; resultView.frame = CGRectMake(0, 0,320,460); [self.view addSubview:resultView];
Swift版本
复制/粘贴到游乐场
var bottomImage:UIImage = UIImage(named:"avatar_4.png") //background image
var imageTop:UIImage = UIImage(named:"group_4.png") //top image
var newSize = CGSizeMake(bottomImage.size.width, bottomImage.size.height) UIGraphicsBeginImageContext( newSize ) bottomImage.drawInRect(CGRectMake(0,0,newSize.width,newSize.height)) // decrease top image to 36x36 imageTop.drawInRect(CGRectMake(18,18,36,36), blendMode:kCGBlendModeNormal, alpha:1.0) var newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext() var imageData = UIImagePNGRepresentation(newImage)
从操场上载图像：
- 打开
playground文件并在那里创build文件夹Resources - 将图像复制到此文件夹
刚刚做了快速粘贴function为您的那些想要使用斯里卡尔应用程序的答案。 （如果背景和前景图像的大小不同）
- (UIImage *) mergeImages:(NSString *)bgImageFileName foreGround:(NSString *)fgImageFileName { UIImage *bottomImage = [UIImage imageNamed:bgImageFileName]; //background image UIImage *image = [UIImage imageNamed:fgImageFileName]; //foreground image CGSize newSize = CGSizeMake(bottomImage.size.width, bottomImage.size.height); UIGraphicsBeginImageContext(newSize); // Use existing opacity as is [bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)]; // Apply supplied opacity if applicable // Change xPos, yPos if applicable [image drawInRect:CGRectMake(11,11,image.size.width,image.size.height) blendMode:kCGBlendModeNormal alpha:1.0]; UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); return newImage; }
在Swift中：
let bottomImage = UIImage(named: "Bottom_Image.png") let frontImage = UIImage (named: "Front_Image.png") let size = CGSize(width: 67, height: 55) UIGraphicsBeginImageContext(size) let areaSize = CGRect(x: 0, y: 0, width: size.width, height: size.height) let frontImageSize = CGRect(x: 14, y: 3, width: 40, height: 40) bottomImage!.drawInRect(areaSize, blendMode: CGBlendMode.Normal, alpha: 1.0) frontImage!.drawInRect(frontImageSize, blendMode: CGBlendMode.Normal, alpha: 1.0) let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext() UIGraphicsEndImageContext()
感谢@Srikar Appal为iOS的灵魂。
对于在OS X中寻找合并的人：
- (NSImage *) mergeImages:(NSString *)bgImageFileName foreGround:(NSString *)fgImageFileName { NSImage *bottomImage = [NSImage imageNamed:bgImageFileName]; NSImage *overlayedImage = [NSImage imageNamed:fgImageFileName]; NSSize newSize = NSMakeSize(bottomImage.size.width, bottomImage.size.height); NSSize overlaySize = NSMakeSize(newSize.width/2, newSize.height/2); //change the size according to your requirements NSImage *newImage = [[NSImage alloc] initWithSize:newSize]; [newImage lockFocus]; [bottomImage drawInRect:NSMakeRect(0, 0, newSize.width, newSize.height)]; [overlayedImage drawInRect:NSMakeRect(newSize.width-overlaySize.width, 0, overlaySize.width, overlaySize.height)]; //set the position as required [newImage unlockFocus]; return newImage; }
你可以按照下面的方法去做另一个技巧 ：
- 将第一个图像添加到imageView。
- 添加第二个图像到另一个imageView。
- 将上述两个imageViews添加到一个主imageView中 ，并通过imageView的属性访问组合图像： mainImageView.image
看看下面的代码：
CGRect rect= investmentDetailTblView.frame; int rows = investmentDetailArray.count; CGFloat heightFinal = 5; CGRect frame1; for (int i=0; i<rows; i++) { frame1 = [investmentDetailTblView rectForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]]; CGFloat height = frame1.size.height; heightFinal = heightFinal + height; } rect.size.height = heightFinal; investmentDetailTblView.frame=rect; UIImageView *imageViewTable = [[UIImageView alloc] init]; [imageViewTable setFrame:CGRectMake(0, 0, frame1.size.width, heightFinal)]; [investmentDetailTblView reloadData]; if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) UIGraphicsBeginImageContextWithOptions(investmentDetailTblView.bounds.size, NO, [UIScreen mainScreen].scale); else UIGraphicsBeginImageContext(investmentDetailTblView.bounds.size); [investmentDetailTblView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); imageViewTable.image = image; //Adding the table image to the image view. CGRect frame=CGRectMake(0, heightFinal+5, investmentDetailTblView.frame.size.width, 20) ; UIView *footerView=[DataStore kkrLogoView]; footerView.frame=frame; if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) UIGraphicsBeginImageContextWithOptions(footerView.frame.size, NO, [UIScreen mainScreen].scale); else UIGraphicsBeginImageContext(footerView.frame.size); [footerView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *kkrLogoImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); UIImageView *imageViewFooter = [[UIImageView alloc] init]; [imageViewFooter setFrame:CGRectMake(0, heightFinal, footerView.frame.size.width, footerView.frame.size.height)]; imageViewFooter.image = kkrLogoImage; //Adding the footer image to the image view. UIImageView *mainImageView = [[UIImageView alloc] init]; [mainImageView setFrame:CGRectMake(0, 0, frame1.size.width, (heightFinal+footerView.frame.size.height))]; [mainImageView addSubview:imageViewTable]; [mainImageView addSubview:imageViewFooter]; if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)]) UIGraphicsBeginImageContextWithOptions(mainImageView.frame.size, NO, [UIScreen mainScreen].scale); else UIGraphicsBeginImageContext(mainImageView.frame.size); [mainImageView.layer renderInContext:UIGraphicsGetCurrentContext()]; UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext();