How to resize NSImage?

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How to Resize NSImage

To resize an NSImage, you can use the imageResize function. This function takes an NSImage and a new size as arguments, and returns a new NSImage that has been resized to the specified size.

The following code shows how to use the imageResize function to resize an NSImage:

``` - (NSImage *)imageResize:(NSImage*)anImage newSize:(NSSize)newSize { NSImage *sourceImage = anImage; [sourceImage setScalesWhenResized:YES]; // Report an error if the source isn't a valid image if (![sourceImage isValid]) { NSLog(@"Invalid Image"); } else { NSImage *smallImage = [[[NSImage alloc] initWithSize: newSize] autorelease]; [smallImage lockFocus]; [sourceImage setSize: newSize]; [[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationHigh]; [sourceImage compositeToPoint:NSZeroPoint operation:NSCompositeCopy]; [smallImage unlockFocus]; return smallImage; } return nil; } ```

You can also resize an NSImage using the NSImage class's size property. This property takes a new size as an argument, and resizes the image to the specified size.

The following code shows how to use the size property to resize an NSImage:

``` NSImage *image = [[NSImage alloc] initWithSize:NSMakeSize(100.0, 100.0)]; [image setSize:NSMakeSize(200.0, 200.0)]; ```

When resizing an NSImage, it is important to consider the image's aspect ratio. If you do not maintain the aspect ratio, the image will be distorted.

You can use the NSImage class's aspectRatio property to get the image's aspect ratio. This property is a floating-point value that represents the ratio of the image's width to its height.

The following code shows how to get the aspect ratio of an NSImage:

``` NSImage *image = [[NSImage alloc] initWithSize:NSMakeSize(100.0, 100.0)]; float aspectRatio = [image aspectRatio]; ```

You can use the aspect ratio to calculate the new size of the image. For example, the following code calculates the new size of an image that will be resized to a width of 200.0 while maintaining its aspect ratio:

``` NSImage *image = [[NSImage alloc] initWithSize:NSMakeSize(100.0, 100.0)]; float aspectRatio = [image aspectRatio]; float newHeight = 200.0 / aspectRatio; NSSize newSize = NSMakeSize(200.0, newHeight); ```

Once you have calculated the new size of the image, you can use the size property to resize the image.