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+ (UIImage*)thumbnailOfImage:(UIImage*)image withSize:(CGSize)aSize
{
//NSLog(@"create thumbnail image");
if (!image)
return nil;
CGImageRef imageRef = [image CGImage];
UIImage *thumb = nil;
// struct CGSize imgSize = [imageRef size];
float _width = CGImageGetWidth(imageRef);
float _height = CGImageGetHeight(imageRef);
// hardcode width and height for now, shouldn't stay like that
float _resizeToWidth;
float _resizeToHeight;
_resizeToWidth = aSize.width;
_resizeToHeight = aSize.height;
float _moveX = 0.0f;
float _moveY = 0.0f;
// determine the start position in the window if it doesn't fit the sizes 100%
//NSLog(@" width: %f to: %f", _width, _resizeToWidth);
//NSLog(@" height: %f to: %f", _height, _resizeToHeight);
// resize the image if it is bigger than the screen only
if ( (_width > _resizeToWidth) || (_height > _resizeToHeight) )
{
float _amount = 0.0f;
if (_width > _resizeToWidth)
{
_amount = _resizeToWidth / _width;
_width *= _amount;
_height *= _amount;
//NSLog(@"1 width: %f height: %f", _width, _height);
}
if (_height > _resizeToHeight)
{
_amount = _resizeToHeight / _height;
_width *= _amount;
_height *= _amount;
//NSLog(@"2 width: %f height: %f", _width, _height);
}
}
_width = (NSInteger)_width;
_height = (NSInteger)_height;
_resizeToWidth = _width;
_resizeToHeight = _height;
CGContextRef bitmap = CGBitmapContextCreate(
NULL,
_resizeToWidth,
_resizeToHeight,
CGImageGetBitsPerComponent(imageRef),
CGImageGetBitsPerPixel(imageRef)*_resizeToWidth,
CGImageGetColorSpace(imageRef),
CGImageGetBitmapInfo(imageRef)
);
// now center the image
_moveX = (_resizeToWidth - _width) / 2;
_moveY = (_resizeToHeight - _height) / 2;
CGContextSetRGBFillColor(bitmap, 1.f, 1.f, 1.f, 1.0f);
CGContextFillRect( bitmap, CGRectMake(0, 0, _resizeToWidth, _resizeToHeight));
// CGContextRotateCTM( bitmap, 180*(M_PI/180));
CGContextDrawImage( bitmap, CGRectMake(_moveX, _moveY, _width, _height), imageRef );
// create a templete imageref.
CGImageRef ref = CGBitmapContextCreateImage( bitmap );
thumb = [UIImage imageWithCGImage:ref];
// release the templete imageref.
CGContextRelease( bitmap );
CGImageRelease( ref );
return [[thumb retain] autorelease];
}