.h文件
#import <Cocoa/Cocoa.h>
#import "NSImage+Conversion.h"
voID releaseMyContextData(CGContextRef content);
CGContextRef MyCreateBitmapContext (int pixelsWIDe,int pixelsHigh);
//判断文件是否存在
BOol pathIsAfile(Nsstring *path);
//通过路径加载NSImage 这样写之后 不能象imagename方法那样可以自动识别大图还是小图(在Retina时)
NSImage* loadNSImageWithname(Nsstring * path);
//通过路径加载CGImageRef
CGImageRef createCGImageWithname(Nsstring * path);
//NSImage to CGImage
CGImageRef createCGImageRefFromNSImage(NSImage* image);
//把一张简单的黑白图对象转成一张mask图片对象
CGImageRef createMaskWithImage(CGImageRef image);
//这个是苹果官方的标准写法
NSImage* createNSImageFromCGImageRef2(CGImageRef image);
//CGImage to NSImage
NSImage* createNSImageFromCGImageRef(CGImageRef image);
//缩放图片 按宽高 (既新的返回图片的宽变成wIDth 高变成height)
CGImageRef createScaleImageByXY(CGImageRef image,float wIDth,float height);
//缩放图片 按比例
CGImageRef createScaleImageByRatio(NSImage *image,float fratio);
BOol saveImagepng(CGImageRef imageRef,Nsstring *strpath);
BOol saveImagejpg(CGImageRef imageRef,Nsstring *strpath);
.m文件
#import "UtilitIEs.h"
voID releaseMyContextData(CGContextRef content){
voID *imgdata =CGBitmapContextGetData(content);
CGContextRelease(content);
if (imgdata) {
free(imgdata);
}
}
CGContextRef MyCreateBitmapContext (int pixelsWIDe,
int pixelsHigh)
{
CGContextRef context = NulL;
CGcolorSpaceRef colorSpace;
glubyte *bitmapData;
int bitmapByteCount;
int bitmapBytesPerRow;
bitmapBytesPerRow = (pixelsWIDe * 4);
bitmapByteCount = (bitmapBytesPerRow * pixelsHigh);
colorSpace = CGcolorSpaceCreateWithname(kCGcolorSpaceGenericRGB);//CGcolorSpaceCreateDeviceRGB();//
//z这里初始化用malloc和calloc都可以 (注意:malloc只能分配内存 初始化所分配的内存空间 calloc则可以)
//在此需要特别注意的是 第二个参数传0进去 如果传比较大的数值进去的话 则会内存泄漏 比如传8之类的就会出现大的泄漏问题
/*如果调用成功,函数malloc()和函数calloc()都
将返回所分配的内存空间的首地址。
函数malloc()和函数calloc()的主要区别是前
者不能初始化所分配的内存空间,而后者能。如
果由malloc()函数分配的内存空间原来没有被
使用过，则其中的每一位可能都是0;反之,如果
这部分内存曾经被分配过,则其中可能遗留有各
种各样的数据。也就是说，使用malloc()函数
的程序开始时(内存空间还没有被重新分配)能
正常进行,但经过一段时间(内存空间还已经被
重新分配)可能会出现问题
函数calloc()会将所分配的内存空间中的每一
位都初始化为零,也就是说,如果你是为字符类
型或整数类型的元素分配内存,那麽这些元素将
保证会被初始化为0;如果你是为指针类型的元
素分配内存,那麽这些元素通常会被初始化为空
指针;如果你为实型数据分配内存,则这些元素
会被初始化为浮点型的零*/
//NSLog(@"%lu",sizeof(glubyte));
bitmapData = (glubyte*)calloc(bitmapByteCount,sizeof(glubyte));//or malloc(bitmapByteCount);//
if (bitmapData == NulL) {
fprintf(stderr,"Memory not allocated!");
return NulL;
}
context = CGBitmapContextCreate(bitmapData,
pixelsWIDe,
pixelsHigh,
8,
bitmapBytesPerRow,
colorSpace,
kCGImageAlphaPremultiplIEdLast);
if (context == NulL) {
free(bitmapData);
);
return NulL;
}
CGcolorSpaceRelease(colorSpace);
return context;
}
//---------------------------------------------------------------------------------
// createCGImageWithname:
//
// simple utility function that create an image from a name by looking into the main bundle
//---------------------------------------------------------------------------------
CGImageRef createCGImageWithname(Nsstring * path)
{
CGImageRef image = NulL;
CFURLRef url = (CFURLRef) [NSURL fileURLWithPath: path];
CGImageSourceRef src = CGImageSourceCreateWithURL(url,NulL);
if( src ) {
//NSDictionary* options = [NSDictionary dictionaryWithObjectsAndKeys: (ID)kcfBooleanFalse,(ID)kCGImageSourceShouldCache,(ID)kcfBooleanTrue,(ID)kCGImageSourceShouldAllowfloat,nil];//[NSNumber numberWithBool:YES],(Nsstring *)kCGImageSourceCreatethumbnailFromImageIfAbsent,[NSNumber numberWithInt:360],(Nsstring *)kCGImageSourcethumbnailMaxPixelSize,nil];
image = CGImageSourceCreateImageAtIndex(src,0,NulL);//(CFDictionaryRef)options);
CFRelease(src);
if(!image) NSLog(@"Warning: CGImageSourceCreateImageAtIndex Failed on file %@ (ptr size=%lu)",path,sizeof(voID*));
}
return image;
}
BOol pathIsAfile(Nsstring *path){
NSfileManager *fileManager = [NSfileManager defaultManager];
BOol isDir,valID = [fileManager fileExistsAtPath:path isDirectory:&isDir];
if (valID) {
}else{
return NO;
}
return YES;
}
NSImage* loadNSImageWithname(Nsstring * path){
fileExistsAtPath:path isDirectory:&isDir];
if (valID) {
}else{
return nil;
}
if ([path isEqualToString:@""] || !path) {
return nil;
}
CGImageRef img = createCGImageWithname(path);
if (!img) {
return nil;
}
NSImage *image = [[NSImage alloc] initWithCGImage:img];
CFRelease(img);
return [image autorelease];
//return [NSImage imagenamed:path];
}
BOol saveImagepng(CGImageRef imageRef,Nsstring *strpath)
{
Nsstring *finalPath = [Nsstring stringWithString:strpath];
CFURLRef url = CFURLCreateWithfileSystemPath (
kcfAllocatorDefault,
(CFStringRef)finalPath,
kcfURLPOSIXPathStyle,
false);
CGImageDestinationRef dest = CGImageDestinationCreateWithURL(url,CFSTR("public.png"),1,NulL);
assert(dest);
CGImageDestinationAddImage(dest,imageRef,NulL);
assert(dest);
if (dest == NulL) {
NSLog(@"CGImageDestinationCreateWithURL Failed");
}
//NSLog(@"%@",dest);
assert(CGImageDestinationFinalize(dest));
//这三句话用来释放对象
CFRelease(dest);
//CGImageRelease(imageRef);
CFRelease(url);
return YES;
}
BOol saveImagejpg(CGImageRef imageRef,
false);
CGImageDestinationRef dest = NulL;
dest = CGImageDestinationCreateWithURL(url,CFSTR("public.jpeg"),NulL);
assert(dest);
cfmutabledictionaryRef mSaveMetaAndOpts = CFDictionaryCreateMutable(nil, 0,
&kcfTypeDictionaryKeyCallBacks, &kcfTypeDictionaryValueCallBacks);
CFDictionarySetValue(mSaveMetaAndOpts,kCGImageDestinationLossyCompressionQuality,
[NSNumber numberWithfloat:0.8]);
CGImageDestinationAddImage(dest,(CFDictionaryRef)mSaveMetaAndOpts);
CFRelease(mSaveMetaAndOpts);
//CGImageDestinationAddImage(dest,NulL);
assert(dest);
if (dest == NulL) {
NSLog(@"CGImageDestinationCreateWithURL Failed");
}
//NSLog(@"%@",129)"> assert(CGImageDestinationFinalize(dest));
//这三句话用来释放对象
CFRelease(dest);
//CGImageRelease(imageRef);
//CFRetain(url);
CFRelease(url);
return YES;
}
CGImageRef createCGImageRefFromNSImage(NSImage* image)
{
NSData *imageData;
CGImageRef imageRef;
@try {
imageData = [image TIFFRepresentation];
if (imageData) {
CGImageSourceRef imageSource = CGImageSourceCreateWithData((CFDataRef)imageData,NulL);
NSDictionary* options = [NSDictionary dictionaryWithObjectsAndKeys:
(ID)kcfBooleanFalse,(ID)kCGImageSourceShouldCache,
(ID)kcfBooleanTrue,(ID)kCGImageSourceShouldAllowfloat,
nil];
//要用这个带option的 kCGImageSourceShouldCache指出不需要系统做cache *** 作 默认是会做的
imageRef = CGImageSourceCreateImageAtIndex(imageSource,(CFDictionaryRef)options);
CFRelease(imageSource);
return imageRef;
}else{
return NulL;
}
}
@catch (NSException *exception) {
}
@finally {
}
return NulL;
}
//这个是苹果官方的标准写法
NSImage* createNSImageFromCGImageRef2(CGImageRef image)
{
NSImage* newImage = nil;
#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5
NSBitmAPImageRep* newRep = [[NSBitmAPImageRep alloc] initWithCGImage:image];
NSSize imageSize;
// Get the image dimensions.
imageSize.height = CGImageGetHeight(image);
imageSize.wIDth = CGImageGetWIDth(image);
newImage = [[NSImage alloc] initWithSize:imageSize];
[newImage addRepresentation:newRep];
[newRep release];
#else
NSRect imageRect = NSMakeRect(0.0,0.0, 0.0);
CGContextRef imageContext = nil;
// Get the image dimensions.
imageRect.size.height = CGImageGetHeight(image);
imageRect.size.wIDth = CGImageGetWIDth(image);
// Create a new image to receive the Quartz image data.
newImage = [[NSImage alloc] initWithSize:imageRect.size];
[newImage lockFocus];
// Get the Quartz context and draw.
imageContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
CGContextDrawImage(imageContext,*(CGRect*)&imageRect,image);
[newImage unlockFocus];
#endif
return newImage;//[newImage autorelease];
}
NSImage* createNSImageFromCGImageRef(CGImageRef image){
NSRect imageRect = NSMakeRect(0,0,0);
CGContextRef imageContext = nil;
NSImage *newImage = nil;
//Get the image dimensions
@try {
imageRect.size.height = CGImageGetHeight(image);
imageRect.size.wIDth = CGImageGetWIDth(image);
//要转换成整数，否则在大图片时可能出现异常
//Create a new image to receive the Quartz image data
newImage = [[NSImage alloc] initWithSize:imageRect.size];
[newImage lockFocus];
//Get the Quartz context and draw
imageContext = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
//CGContextSaveGState(imageContext);
CGContextDrawImage(imageContext,*(CGRect*)&imageRect,image);
//CGContextRestoreGState(imageContext);
[newImage unlockFocus];
//CFRelease(imageContext);
}
@catch (NSException *exception) {
}
@finally {
}
return newImage;
}
CGImageRef createMaskWithImage(CGImageRef image)
{
//NSAssert(image != NulL,@"The Foo pointer must not be NulL!");
if (image == NulL) {
return NulL;
}
@try {
int mw = (int)CGImageGetWIDth(image);
int mh = (int)CGImageGetHeight(image);
//round bytesPerRow to the nearest 16 bytes,for performance's sake
int bytesPerRow = (mw + 15)&0xfffffff0;
//int bufferSize = bytesPerRow * mh;
glubyte *imgdata = (glubyte*) calloc(mw * mh * 4,sizeof(glubyte));
//the data will be 8 bits per pixel,no Alpha
CGcolorSpaceRef cSpace = CGcolorSpaceCreateDeviceGray();//CGcolorSpaceCreateWithname(kCGcolorSpaceGenericRGB);
CGContextRef content = CGBitmapContextCreate(imgdata,mw,mh,8,bytesPerRow,cSpace,
kCGImageAlphaNone);
CGContextDrawImage(content, CGRectMake(0,mh),image);
CGImageRef mask = CGBitmapContextCreateImage(content);
CFRelease(cSpace);
CGContextRelease(content);
free(imgdata);
return mask;
}
@catch (NSException *exception) {
}
@finally {
}
return NulL;
}
CGImageRef createScaleImageByXY(CGImageRef image,float height) {
CGContextRef content = MyCreateBitmapContext(wIDth,height);
CGContextDrawImage(content,wIDth,height),image);
CGImageRef img = CGBitmapContextCreateImage(content);
releaseMyContextData(content);
return img;
}
CGImageRef createScaleImageByRatio(NSImage *image,float fratio){
NSData *imageData;
imageData = [image TIFFRepresentation];
if (imageData) {
CGImageSourceRef imageSource = CGImageSourceCreateWithData((CFDataRef)imageData,NulL);
NSDictionary *options = [[NSDictionary alloc] initWithObjectsAndKeys:
// Ask ImageIO to create a thumbnail from the file's image data,if it can't find a suitable existing thumbnail image in the file. We Could comment out the following line if only existing thumbnails were desired for some reason (maybe to favor performance over being guaranteed a complete set of thumbnails).
[NSNumber numberWithBool:YES],(Nsstring *)kCGImageSourceCreatethumbnailFromImageIfAbsent,
[NSNumber numberWithInt:[image size].wIDth*fratio],(Nsstring *)kCGImageSourcethumbnailMaxPixelSize,
nil];
CGImageRef thumbnail = CGImageSourceCreatethumbnailAtIndex(imageSource,(CFDictionaryRef)options);
CFRelease(imageSource);
return thumbnail;
}
return nil;
}
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