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[Stitch]

I'm trying to resize UIImages before saving them as images to the documents folder.

I've implemented the code below from PhoneyDeveloper which is working well for resizing my images.

The trouble is the images are rotated 90 degrees anti-clockwise. Is there an easy way to fix this? Or another solution to resize UIImages? It must be documented though.

Thanks

Originally Posted by PhoneyDeveloper

//	==============================================================
//	resizedImage
//	==============================================================
// Return a scaled down copy of the image.  

UIImage* resizedImage(UIImage *inImage, CGRect thumbRect)
{
	CGImageRef			imageRef = [inImage CGImage];
	CGImageAlphaInfo	alphaInfo = CGImageGetAlphaInfo(imageRef);
	
	// There's a wierdness with kCGImageAlphaNone and CGBitmapContextCreate
	// see Supported Pixel Formats in the Quartz 2D Programming Guide
	// Creating a Bitmap Graphics Context section
	// only RGB 8 bit images with alpha of kCGImageAlphaNoneSkipFirst, kCGImageAlphaNoneSkipLast, kCGImageAlphaPremultipliedFirst,
	// and kCGImageAlphaPremultipliedLast, with a few other oddball image kinds are supported
	// The images on input here are likely to be png or jpeg files
	if (alphaInfo == kCGImageAlphaNone)
		alphaInfo = kCGImageAlphaNoneSkipLast;

	// Build a bitmap context that's the size of the thumbRect
	CGContextRef bitmap = CGBitmapContextCreate(
				NULL,
				thumbRect.size.width,		// width
				thumbRect.size.height,		// height
				CGImageGetBitsPerComponent(imageRef),	// really needs to always be 8
				4 * thumbRect.size.width,	// rowbytes
				CGImageGetColorSpace(imageRef),
				alphaInfo
		);

	// Draw into the context, this scales the image
	CGContextDrawImage(bitmap, thumbRect, imageRef);

	// Get an image from the context and a UIImage
	CGImageRef	ref = CGBitmapContextCreateImage(bitmap);
	UIImage*	result = [UIImage imageWithCGImage:ref];

	CGContextRelease(bitmap);	// ok if NULL
	CGImageRelease(ref);

	return result;
}