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Created June 15, 2013 00:18
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@implementation UIImage (WRExtensions)
#pragma mark -
#pragma mark Scale and crop image
- (UIImage*)imageByScalingAndCroppingForSize:(CGSize)targetSize
{
UIImage *sourceImage = self;
UIImage *newImage = nil;
CGSize imageSize = sourceImage.size;
CGFloat width = imageSize.width;
CGFloat height = imageSize.height;
CGFloat targetWidth = targetSize.width;
CGFloat targetHeight = targetSize.height;
CGFloat scaleFactor = 0.0;
CGFloat scaledWidth = targetWidth;
CGFloat scaledHeight = targetHeight;
CGPoint thumbnailPoint = CGPointMake(0.0,0.0);
if (CGSizeEqualToSize(imageSize, targetSize) == NO)
{
CGFloat widthFactor = targetWidth / width;
CGFloat heightFactor = targetHeight / height;
if (widthFactor > heightFactor)
scaleFactor = widthFactor; // scale to fit height
else
scaleFactor = heightFactor; // scale to fit width
scaledWidth = width * scaleFactor;
scaledHeight = height * scaleFactor;
// center the image
if (widthFactor > heightFactor)
{
thumbnailPoint.y = (targetHeight - scaledHeight) * 0.5;
}
else
if (widthFactor < heightFactor)
{
thumbnailPoint.x = (targetWidth - scaledWidth) * 0.5;
}
}
UIGraphicsBeginImageContext(targetSize); // this will crop
CGRect thumbnailRect = CGRectZero;
thumbnailRect.origin = thumbnailPoint;
thumbnailRect.size.width = scaledWidth;
thumbnailRect.size.height = scaledHeight;
[sourceImage drawInRect:thumbnailRect];
newImage = UIGraphicsGetImageFromCurrentImageContext();
if(newImage == nil)
NSLog(@"could not scale image");
//pop the context to get back to the default
UIGraphicsEndImageContext();
return newImage;
}
- (UIImage*)croppedImageWithRect:(CGRect)croppedRect
{
// Draw new image in current graphics context
CGImageRef imageRef = CGImageCreateWithImageInRect([self CGImage], croppedRect);
// Create new cropped UIImage
UIImage *croppedImage = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
return croppedImage;
}
- (UIColor*)averageColor
{
int count = 10000;
UIImage *customPixelImage = [self imageByScalingAndCroppingForSize:CGSizeMake(90.0f, 90.0f)];
NSMutableArray *result = [NSMutableArray arrayWithCapacity:count];
// First get the image into your data buffer
CGImageRef imageRef = [customPixelImage CGImage];
NSUInteger width = CGImageGetWidth(imageRef);
NSUInteger height = CGImageGetHeight(imageRef);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
unsigned char *rawData = (unsigned char*) calloc(height * width * 4, sizeof(unsigned char));
NSUInteger bytesPerPixel = 4;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef context = CGBitmapContextCreate(rawData, width, height,
bitsPerComponent, bytesPerRow, colorSpace,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
CGContextRelease(context);
// Now your rawData contains the image data in the RGBA8888 pixel format.
int byteIndex = (bytesPerRow * 1) + 1 * bytesPerPixel;
for (int ii = 0 ; ii < count ; ++ii)
{
CGFloat red = (rawData[byteIndex] * 1.0) / 255.0;
CGFloat green = (rawData[byteIndex + 1] * 1.0) / 255.0;
CGFloat blue = (rawData[byteIndex + 2] * 1.0) / 255.0;
CGFloat alpha = (rawData[byteIndex + 3] * 1.0) / 255.0;
byteIndex += 4;
NSLog(@"red is %1.2f", red);
NSLog(@"green is %1.2f", green);
NSLog(@"blue is %1.2f", blue);
NSLog(@"alpha is %1.2f", alpha);
UIColor *acolor = [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
[result addObject:acolor];
}
NSLog(@"count array %@", result);
free(rawData);
return (UIColor*)[result objectAtIndex:0];
}
- (NSArray*)averageColorArray
{
int count = 10000;
UIImage *onePixelImage = [self imageByScalingAndCroppingForSize:CGSizeMake(100.0f, 100.0f)];
// UIImageWriteToSavedPhotosAlbum(onePixelImage,
// self, // send the message to 'self' when calling the callback
// nil, // the selector to tell the method to call on completion
// NULL);
NSMutableArray *result = [NSMutableArray arrayWithCapacity:count];
NSMutableDictionary *colorDictionary = [[NSMutableDictionary alloc] init];
// First get the image into the data buffer
CGImageRef imageRef = [onePixelImage CGImage];
NSUInteger width = CGImageGetWidth(imageRef);
NSUInteger height = CGImageGetHeight(imageRef);
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
unsigned char *rawData = (unsigned char*) calloc(height * width * 4, sizeof(unsigned char));
NSUInteger bytesPerPixel = 4;
NSUInteger bytesPerRow = bytesPerPixel * width;
NSUInteger bitsPerComponent = 8;
CGContextRef context = CGBitmapContextCreate(rawData, width, height,
bitsPerComponent, bytesPerRow, colorSpace,
kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), imageRef);
CGContextRelease(context);
// Now your rawData contains the image data in the RGBA8888 pixel format.
int byteIndex = (bytesPerRow * 1) + 1 * bytesPerPixel;
NSString *colorKey;
for (int ii = 0 ; ii < count ; ++ii)
{
CGFloat red = (rawData[byteIndex] * 1.0) / 255.0;
CGFloat green = (rawData[byteIndex + 1] * 1.0) / 255.0;
CGFloat blue = (rawData[byteIndex + 2] * 1.0) / 255.0;
CGFloat alpha = (rawData[byteIndex + 3] * 1.0) / 255.0;
byteIndex += 4;
// float hue, saturation, luminosity;
// RGB2HSL(red, green, blue, &hue, &saturation, &luminosity);
// NSLog(@"red is %1.2f", red);
// NSLog(@"green is %1.2f", green);
// NSLog(@"blue is %1.2f", blue);
// NSLog(@"alpha is %1.2f", alpha);
colorKey = [NSString stringWithFormat:@"%1.3f,%1.3f,%1.3f,%1.3f", red, green, blue, alpha];
if ([colorDictionary objectForKey:colorKey]) {
NSNumber *numberOfColors = [NSNumber numberWithInt:[[colorDictionary objectForKey:colorKey] intValue] + 1];
[colorDictionary setObject:numberOfColors forKey:colorKey];
} else {
[colorDictionary setObject:[NSNumber numberWithInt:1] forKey:colorKey];
}
}
// NSLog(@"color dictionary %@", colorDictionary);
// NSArray *sortedColorArray = [colorDictionary keysSortedByValueUsingSelector:@selector(compare:)];
// NSLog(@"sortedColorArray %@", sortedColorArray);
CGFloat red = 0, green = 0, blue = 0;
for (NSString *rgbColor in [colorDictionary allKeys]) {
NSArray *rgbArray = [rgbColor componentsSeparatedByString:@","];
red = [[rgbArray objectAtIndex:0] floatValue];
green = [[rgbArray objectAtIndex:1] floatValue];
blue = [[rgbArray objectAtIndex:2] floatValue];
UIColor *acolor = [UIColor colorWithRed:red green:green blue:blue alpha:1.0f];
[result addObject:acolor];
}
free(rawData);
NSLog(@"result colors %d", [result count]);
return result;
}
//Taken from stackoverflow http://stackoverflow.com/questions/12147779/how-do-i-release-a-cgimageref-in-ios/12148136#12148136
- (UIColor *)mergedColor
{
CGSize size = {1, 1};
UIGraphicsBeginImageContext(size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextSetInterpolationQuality(ctx, kCGInterpolationMedium);
[self drawInRect:(CGRect){.size = size} blendMode:kCGBlendModeCopy alpha:1];
uint8_t *data = CGBitmapContextGetData(ctx);
UIColor *color = [UIColor colorWithRed:data[2] / 255.0f
green:data[1] / 255.0f
blue:data[0] / 255.0f
alpha:1];
UIGraphicsEndImageContext();
return color;
}
@end
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