//1.加载要添加水印的图片

UIImage * image = [UIImage imageNamed:@"img05"];

//2.开启一个和图片大小相同的图形上下文对象 (bitmap)

UIGraphicsBeginImageContextWithOptions(image.size, NO, 0.0);

//3.绘制图片

[image drawAtPoint:CGPointZero];

//4.添加文字水印

NSString * str = @"美人你一直是我的春天,你是我生命中的世外桃源";

NSDictionary * atts = @{

NSFontAttributeName:[UIFont systemFontOfSize:25.f],

NSForegroundColorAttributeName:[UIColor redColor]

};

[str drawInRect:CGRectMake(200, 500, 300, 200) withAttributes:atts];

//5.添加图片水印

UIImage * logoImage = [UIImage imageNamed:@"logo"];

[logoImage drawAtPoint:CGPointMake(300, 900)];

//6.从图形上下文中获取图片

UIImage * getImage = UIGraphicsGetImageFromCurrentImageContext();

//7.结束图形上下文

UIGraphicsEndImageContext();

//8.使用图片

UIImageWriteToSavedPhotosAlbum(getImage, nil, nil, nil);