iOS图片拼接,图片文字合成总结
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2022-07-03 21:15:20
iOS图片拼接,图片文字合成总结
一、注意事项:项目报错,图片模糊,内存问题,离屏渲染
二、以下是合成的步骤:
1、先读取两张图片把创建出CGImageRef
2、创建上下...
iOS图片拼接,图片文字合成总结
一、注意事项:项目报错,图片模糊,内存问题,离屏渲染
二、以下是合成的步骤:
1、先读取两张图片把创建出CGImageRef
2、创建上下文画布
3、把图片依次画在画布指定位置上
4、从上下文中获得合并后的图片
5、关闭上下文
6、释放内存
7、两张图片合成:
(void)composeImg { UIImage *img = [UIImage imageNamed:@"0.png"]; CGImageRef imgRef = img.CGImage; CGFloat w = CGImageGetWidth(imgRef); CGFloat h = CGImageGetHeight(imgRef); //以1.png的图大小为底图 UIImage *img1 = [UIImage imageNamed:@"1.png"]; CGImageRef imgRef1 = img1.CGImage; CGFloat w1 = CGImageGetWidth(imgRef1); CGFloat h1 = CGImageGetHeight(imgRef1); //以1.png的图大小为画布创建上下文 UIGraphicsBeginImageContext(CGSizeMake(w1, h1)); [img1 drawInRect:CGRectMake(0, 0, w1, h1)];//先把1.png 画到上下文中 [img drawInRect:CGRectMake(100, 100, w, h)];//再把小图放在上下文中 UIImage *resultImg = UIGraphicsGetImageFromCurrentImageContext();//从当前上下文中获得最终图片 UIGraphicsEndImageContext();//关闭上下文 NSString *path = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject]; NSString *filePath = [path stringByAppendingPathComponent:@"01.png"]; [UIImagePNGRepresentation(resultImg) writeToFile:filePath atomically:YES];//保存图片到沙盒 CGImageRelease(imgRef); CGImageRelease(imgRef1); }
图片与文字合成:
(UIImage *)CSImage:(UIImage *)img AddText:(NSString *)text { UIImageView *view = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, img.size.width, img.size.height)]; view.image = img; UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0,0,0,0)]; [label setNumberOfLines:0]; label.lineBreakMode = UILineBreakModeWordWrap; NSString *s = text; UIFont *font = [UIFont fontWithName:@"Arial" size:12]; CGSize size = CGSizeMake(320,2000); CGSize labelsize = [s sizeWithFont:font constrainedToSize:size lineBreakMode:UILineBreakModeWordWrap]; label.frame = CGRectMake(0,0, labelsize.width, labelsize.height); [view addSubview:label]; return [self convertViewToImage:view]; } -(UIImage*)convertViewToImage:(UIView*)v { CGSize s = v.bounds.size; UIGraphicsBeginImageContextWithOptions(s, NO, [UIScreen mainScreen].scale); CGContextRef context = UIGraphicsGetCurrentContext(); [v.layer renderInContext:context]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); v.layer.contents = nil; return image; }
图片模糊问题,解决方法:1本身图片有问题,2图片压缩的太狠了,3使用WithOptions函数