Question

我正在尝试以编程方式从1024x1024图像创建大小为120 * 120的ICNS。目前我正在创建一个NSImage，然后我用适当的分辨率创建CGImageRef对象，最后我用CGImageDestinationAddImage（）将它们保存到路径。

我经历了各种链接，其中一个是： Creating an ICNS Programmatically : "Unsupported Image Size"

但问题是，代码生成了相同大小的图标文件。（1024 * 1024）

以下是代码：

- (void)generateIconSizeFromImage:(NSString *)path

{

//destination path

NSURL *fileURL = [NSURL fileURLWithPath:@"/Users/harjotsingh/Desktop/TestIconGenerated/test1@2x.png"];
CGImageDestinationRef dr = CGImageDestinationCreateWithURL((__bridge CFURLRef)fileURL, kUTTypePNG , 1, NULL);

//image from path
NSImage *img = [[NSImage alloc] initWithContentsOfFile:path];

//setting its size to one of icon size
[img setSize:NSMakeSize(60,60)];

//setting its rep size to one of icon size
for (NSImageRep *rep in [img representations])[rep setSize:NSMakeSize(60,60)];

//setting the dpi, so it create 120 * 120 size icon file
NSDictionary *imageProps1x = @{
                               (__bridge NSString *)kCGImagePropertyDPIWidth: @144.0,
                               (__bridge NSString *)kCGImagePropertyDPIHeight: @144.0,
                               };

// Add rect size
NSRect prect = NSMakeRect(0,0,60,60);

//get image for desired size
CGImageRef generatedImage = [img CGImageForProposedRect:&prect context:[NSGraphicsContext currentContext] hints:nil];

//sadly it shows the same 1024 * 1024 size
NSLog(@"width:-- %zu && height:-- %zu",CGImageGetWidth(generatedImage),CGImageGetHeight(generatedImage));

//adding to destination folder
CGImageDestinationAddImage(dr, generatedImage, (__bridge CFDictionaryRef)(imageProps1x));

//finalize.
CGImageDestinationFinalize(dr);

CFRelease(dr); }

输入路径使用的图像为1024 * 1024像素。 “1024×1024像素元素的正确规格为512点@ 2x。这是（NSSize）{512.0,512.0}（点）的大小（图像和代表），代表是1024像素宽和1024像素高。“ 注意：这已经得到了解决，但仍然没有成功。

如有任何关于我的问题的疑问，请与我联系。

感谢您的帮助。

Answer 1

我已经完成了这项工作并完成了一些改动。这是从大尺寸图像生成图标的工作代码：

- (void)generateIconSizeFromImage:(NSString *)path

{

NSImage * smallImage = [[NSImage alloc] initWithContentsOfFile:path];
[smallImage setSize:NSMakeSize(120,120)];

[smallImage lockFocus];

[[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationHigh];

[smallImage drawInRect:CGRectMake(0, 0, 120,120)];

[smallImage unlockFocus];


//destination path
NSURL *fileURL = [NSURL fileURLWithPath:@"/Volumes/Harjot/Documents/MyProjects/Cobby Mac App/test60@2x.png"];

CGImageDestinationRef dr = CGImageDestinationCreateWithURL((__bridge CFURLRef)fileURL, kUTTypePNG , 1, NULL);

//setting the dpi, so it create 120 * 120 size icon file
NSDictionary *imageProps1x = @{
                               (__bridge NSString *)kCGImagePropertyDPIWidth: @144.0,
                               (__bridge NSString *)kCGImagePropertyDPIHeight: @144.0,
                               };

//get image for desired size
CGImageRef generatedImage = [smallImage CGImageForProposedRect:NULL context:[NSGraphicsContext currentContext] hints:nil];

//now it works and generate the 120 by 120 icon
NSLog(@"width:-- %zu && height:-- %zu",CGImageGetWidth(generatedImage),CGImageGetHeight(generatedImage));

//adding to destination folder
CGImageDestinationAddImage(dr, generatedImage, (__bridge CFDictionaryRef)(imageProps1x));

//finalize.
CGImageDestinationFinalize(dr);

CFRelease(dr);

}

享受：）

Answer 2

draw rect方法适用于此。这是示例代码：

[smallImage drawInRect:CGRectMake(0, 0, 120,120)]


//destination path
NSURL *fileURL = [NSURL fileURLWithPath:@“Your saving path…];

CGImageDestinationRef dr = CGImageDestinationCreateWithURL((__bridge CFURLRef)fileURL, kUTTypePNG , 1, NULL);

//setting the dpi, so it create 120 * 120 size icon file
NSDictionary *imageProps1x = @{
                               (__bridge NSString *)kCGImagePropertyDPIWidth: @144.0,
                               (__bridge NSString *)kCGImagePropertyDPIHeight: @144.0,
                               };

//get image for desired size
CGImageRef generatedImage = [smallImage CGImageForProposedRect:NULL context:[NSGraphicsContext currentContext] hints:nil];

//now it works and generate the 120 by 120 icon
NSLog(@"width:-- %zu && height:-- %zu",CGImageGetWidth(generatedImage),CGImageGetHeight(generatedImage));

//adding to destination folder
CGImageDestinationAddImage(dr, generatedImage, (__bridge CFDictionaryRef)(imageProps1x));

以1024 * 1024大小的NSImage编程创建图标（ICNS）

2 个答案: