分享类型：应用开发相关
ios图片加水印或文字
详情可见附件，我亲自测试了一下，发现原来的方法确实存在诸多问题，重新写了一下，大家随意取用，有问题再交流
1.加文字
- (UIImage *)imageWithLogoText:(UIImage *)img text:(NSString*)text1
{
/////注：此为后来更改，用于显示中文。zyq,2013-5-8
CGSize size = CGSizeMake(200, img.size.height);//设置上下文（画布）大小
UIGraphicsBeginImageContext(size);//创建一个基于位图的上下文(context)，并将其设置为当前上下文
CGContextRef contextRef = UIGraphicsGetCurrentContext();//获取当前上下文
CGContextTranslateCTM(contextRef, 0, img.size.height);//画布的高度
CGContextScaleCTM(contextRef, 1.0, -1.0);//画布翻转
CGContextDrawImage(contextRef, CGRectMake(0, 0, img.size.width, img.size.height), [img CGImage]);//在上下文种画当前图片
[[UIColor redColor] set];//上下文种的文字属性
CGContextTranslateCTM(contextRef, 0, img.size.height);
CGContextScaleCTM(contextRef, 1.0, -1.0);
UIFont *font = [UIFont boldSystemFontOfSize:16];
[text1 drawInRect:CGRectMake(0, 0, 200, 80) withFont:font];//此处设置文字显示的位置
UIImage *targetimg =UIGraphicsGetImageFromCurrentImageContext();//从当前上下文种获取图片
UIGraphicsEndImageContext();//移除栈顶的基于当前位图的图形上下文。
returntargetimg;
//注：此为原来，不能显示中文。无用。
//get image width and height
intw = img.size.width;
inth = img.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
//create a graphic context with CGBitmapContextCreate
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextSetRGBFillColor(context, 0.0, 1.0, 1.0, 1);
char* text = (char*)[text1 cStringUsingEncoding:NSUnicodeStringEncoding];
CGContextSelectFont(context,"Georgia", 30, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);
CGContextSetRGBFillColor(context, 255, 0, 0, 1);
CGContextShowTextAtPoint(context, w/2-strlen(text)*5, h/2, text, strlen(text));
//Create image ref from the context
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return[UIImage imageWithCGImage:imageMasked];
}
2.新的添加文字水印的方法一
#pragma mark -也是文字水印
- (UIImage *) imageWithStringWaterMark:(NSString*)markString inRect:(CGRect)rect color:(UIColor *)color font:(UIFont *)font
{
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 40000
if([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)
{
UIGraphicsBeginImageContextWithOptions([selfsize],NO, 0.0);// 0.0 for scale means "scale for device's main screen".
}
#else
if([[[UIDevice currentDevice] systemVersion] floatValue] < 4.0)
{
UIGraphicsBeginImageContext([selfsize]);
}
#endif
//原图
[selfdrawInRect:CGRectMake(0, 0,self.size.width,self.size.height)];
//文字颜色
[color set];
//水印文字
[markString drawInRect:rect withFont:font];
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
returnnewPic;
}
3.还是添加文字水印方法二
#pragma mark -还是文字水印
- (UIImage *) imageWithStringWaterMark:(NSString*)markString atPoint:(CGPoint)point color:(UIColor *)color font:(UIFont *)font
{
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 40000
if([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)
{
UIGraphicsBeginImageContextWithOptions([selfsize],NO, 0.0);// 0.0 for scale means "scale for device's main screen".
}
#else
if([[[UIDevice currentDevice] systemVersion] floatValue] < 4.0)
{
UIGraphicsBeginImageContext([selfsize]);
}
#endif
//原图
[selfdrawInRect:CGRectMake(0, 0,self.size.width,self.size.height)];
//文字颜色
[color set];
//水印文字
[markString drawAtPoint:point withFont:font];
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
returnnewPic;
}
4.加图片
#pragma mark - 加图片水印
-(UIImage *)imageWithLogoImage:(UIImage *)img logo:(UIImage *)logo
{
//get image width and height
intw = img.size.width;
inth = img.size.height;
intlogoWidth = logo.size.width;
intlogoHeight = logo.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
//create a graphic context with CGBitmapContextCreate
CGContextRef context = CGBitmapContextCreate(NULL, w, h, 8, 4 * w, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context, CGRectMake(0, 0, w, h), img.CGImage);
CGContextDrawImage(context, CGRectMake(w-logoWidth, 0, logoWidth, logoHeight), [logo CGImage]);
CGImageRef imageMasked = CGBitmapContextCreateImage(context);
CGContextRelease(context);
CGColorSpaceRelease(colorSpace);
return[UIImage imageWithCGImage:imageMasked];
// CGContextDrawImage(contextRef, CGRectMake(100, 50, 200, 80), [smallImg CGImage]);
}
5.新的添加图片水印的方法
#pragma mark -还是图片水印
- (UIImage *) imageWithWaterMask:(UIImage*)mask inRect:(CGRect)rect
{
#if __IPHONE_OS_VERSION_MAX_ALLOWED >= 40000
if([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)
{
UIGraphicsBeginImageContextWithOptions([selfsize],NO, 0.0);// 0.0 for scale means "scale for device's main screen".
}
#else
if([[[UIDevice currentDevice] systemVersion] floatValue] < 4.0)
{
UIGraphicsBeginImageContext([selfsize]);
}
#endif
//原图
[selfdrawInRect:CGRectMake(0, 0,self.size.width,self.size.height)];
//水印图
[mask drawInRect:rect];
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
returnnewPic;
}
6 .加半透明的水印
//加半透明的水印
-(UIImage *)imageWithTransImage:(UIImage *)useImage addtransparentImage:(UIImage *)transparentimg
{
UIGraphicsBeginImageContext(useImage.size);
[useImage drawInRect:CGRectMake(0, 0, useImage.size.width, useImage.size.height)];
[transparentimg drawInRect:CGRectMake(0, useImage.size.height-transparentimg.size.height, transparentimg.size.width, transparentimg.size.height) blendMode:kCGBlendModeOverlay alpha:0.4f];
UIImage *resultingImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
returnresultingImage;
}
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