Alan aynı piksel rengi ile kaplanmış ve aynı renkle kaplı belirli piksel ve piksel alanının rengini nasıl sildiğimi değiştirir

Question

. Aşağıdaki hızlı kodu kullanarak belirli bir piksel rengini alabiliyorum ancak alabiliyorum aynı renk pikseline sahip olan ve onu silemeyen çevre alanı. Örneğin

import UIKit 
 

 
class ColorOfImage: UIImageView { 
 
    
 
    var lastColor:UIColor? = nil 
 

 

 
    
 
    /* 
 
    // Only override draw() if you perform custom drawing. 
 
    // An empty implementation adversely affects performance during animation. 
 
    override func draw(_ rect: CGRect) { 
 
    // Drawing code 
 
    } 
 
    */ 
 
    
 
    override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) { 
 
     
 
     if self.isHidden == true { 
 
      
 
      self.next?.touchesEnded(touches, with: event) 
 
      return 
 
     } 
 
     
 
     let touch: UITouch = touches.first! 
 
     
 
     var point:CGPoint = touch.location(in: self) 
 
     self.lastColor = self.getPixelColorAtLocation(point:point) 
 
    } 
 
    
 
    
 
    public func createARGBBitmapContext(inImage: CGImage) -> CGContext { 
 

 
     var bitmapByteCount = 0 
 
     var bitmapBytesPerRow = 0 
 
     
 
     //Get image width, height 
 
     let pixelsWide = inImage.width 
 
     let pixelsHigh = inImage.height 
 
     
 
     // Declare the number of bytes per row. Each pixel in the bitmap in this 
 
     // example is represented by 4 bytes; 8 bits each of red, green, blue, and 
 
     // alpha. 
 
     bitmapBytesPerRow = Int(pixelsWide) * 4 
 
     bitmapByteCount = bitmapBytesPerRow * Int(pixelsHigh) 
 
     
 
     // Use the generic RGB color space. 
 
     let colorSpace = CGColorSpaceCreateDeviceRGB() 
 
     
 
     
 
     
 
     // Allocate memory for image data. This is the destination in memory 
 
     // where any drawing to the bitmap context will be rendered. 
 
     let bitmapData = malloc(bitmapByteCount) 
 
     
 
     // Create the bitmap context. We want pre-multiplied ARGB, 8-bits 
 
     // per component. Regardless of what the source image format is 
 
     // (CMYK, Grayscale, and so on) it will be converted over to the format 
 
     // specified here by CGBitmapContextCreate. 
 
     let context = CGContext(data: bitmapData, width: pixelsWide, height: pixelsHigh, bitsPerComponent: 8, bytesPerRow: bitmapBytesPerRow, space: colorSpace, bitmapInfo: CGImageAlphaInfo.premultipliedFirst.rawValue) 
 
     
 
     // Make sure and release colorspace before returning 
 
     return context! 
 
    } 
 
    
 
    
 
    
 
    
 
    public func getPixelColorAtLocation(point:CGPoint) -> UIColor { 
 
     // Create off screen bitmap context to draw the image into. Format ARGB is 4 bytes for each pixel: Alpa, Red, Green, Blue 
 
     var point = point 
 
     
 
     var context:CGContext? = nil 
 
     
 
     context = self.createARGBBitmapContext(inImage: (self.image?.cgImage)!) 
 
     
 
     
 
     if context == nil { 
 
      return UIColor.white 
 
     } 
 
     
 
     var pixelsWide = (self.image?.cgImage)!.width 
 
     var pixelsHigh = (self.image?.cgImage)!.height 
 
     var rect = CGRect(x:0, y:0, width:Int(pixelsWide), height:Int(pixelsHigh)) 
 
     
 
     var xScale:CGFloat = CGFloat(pixelsWide)/self.frame.size.width 
 
     var yScale:CGFloat = CGFloat(pixelsHigh)/self.frame.size.height 
 
     
 
     
 
     point.x = point.x * xScale 
 
     point.y = point.y * yScale 
 
     
 
     
 
     
 
     var x:CGFloat = 1.0 
 
     
 
     
 
     
 
     if (self.image?.responds(to: #selector(getter: self.image?.scale)))! { 
 
      x = (self.image!.scale) 
 
      
 
     } 
 
     
 
     
 
     
 
     //Clear the context 
 
     context?.clear(rect) 
 
     
 
     // Draw the image to the bitmap context. Once we draw, the memory 
 
     // allocated for the context for rendering will then contain the 
 
     // raw image data in the specified color space. 
 
     
 
     context?.draw((self.image?.cgImage)!, in: rect) 
 
     
 
     // Now we can get a pointer to the image data associated with the bitmap 
 
     // context. 
 
     
 
     
 
     let data = context?.data 
 
     // let dataType = UnsafePointer<UInt8>(data) 
 
     
 
     var color:UIColor? = nil 
 
     if data != nil { 
 
      let dataType = data?.assumingMemoryBound(to: UInt8.self) 
 
      
 
      
 
      let offset = 4*((Int(pixelsWide) * Int(point.y)) + Int(point.x)) 
 
      let alpha = dataType?[offset] 
 
      let red = dataType?[offset+1] 
 
      let green = dataType?[offset+2] 
 
      let blue = dataType?[offset+3] 
 
      color = UIColor(red: CGFloat(red!)/255.0, green: CGFloat(green!)/255.0, blue: CGFloat(blue!)/255.0, alpha: CGFloat(alpha!)/255.0) 
 
     } 
 
     else 
 
     { 
 
      
 
      
 
     } 
 
     
 
     
 
     
 
     // Free image data memory for the context 
 
     free(data) 
 
     return color!; 
 
    } 
 
}

i UIImage ve özellikle koordinatlarda dokunursanız o zaman rengini almak ve aynı renge sahip bu pikseli ve çevresindeki pikselleri silmek için vardır ve tüm bu erase.Can zorunda Biri bana bu konuda yardımcı olun.

Answer 1

Ay önce Bir görüntü aldığınız ve renkleri değiştirmeniz gereken bir Uygulama için çalıştım. Sizin için yararlı olup olmayacağını bilmiyorum. Bunun için bir UIImage kategorisi hazırladım. Bu, bu floodfill algoritma gibi aynıdır ancak bunun yerine ben özellikle de renk pikseli almak istiyorum koordinatları doğru 0,0 rengi değişecek

#import <UIKit/UIKit.h> 

@interface UIImage (YPKInterface) 
+ (UIImage *)swapImage:(UIImage *)image color:(UIColor *)originalColor withColor:(UIColor *)swappedColor andThreshold:(float)threshold; 
@end 

#import "UIImage+YPKInterface.h" 

@implementation UIImage (YPKInterface) 

+ (UIImage *)swapImage:(UIImage *)image color:(UIColor *)originalColor  withColor:(UIColor *)swappedColor andThreshold:(float)threshold { 

int count = image.size.width*image.size.height; 

// Convert image in raw data 
CGImageRef imageRef = [image 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); 

// Scan all the pixels 
NSUInteger byteIndex = 0; 
for (int i = 0 ; i < count ; ++i) 
{ 
    CGFloat alpha = ((CGFloat) rawData[byteIndex + 3])/255.0f; 
      CGFloat red = ((CGFloat) rawData[byteIndex] )/alpha; 
      CGFloat green = ((CGFloat) rawData[byteIndex + 1])/alpha; 
      CGFloat blue = ((CGFloat) rawData[byteIndex + 2])/alpha; 

    // Change the color 

    // RGBA of the colors 
    float origR = CGColorGetComponents(originalColor.CGColor)[0] * 255; 
    float origG = CGColorGetComponents(originalColor.CGColor)[1] * 255; 
    float origB = CGColorGetComponents(originalColor.CGColor)[2] * 255; 
    //float origA = CGColorGetComponents(originalColor.CGColor)[3]; 

    float swapR = CGColorGetComponents(swappedColor.CGColor)[0] * 255; 
    float swapG = CGColorGetComponents(swappedColor.CGColor)[1] * 255; 
    float swapB = CGColorGetComponents(swappedColor.CGColor)[2] * 255; 
    //float swapA = CGColorGetComponents(swappedColor.CGColor)[3]; 

    if (red >= origR - threshold && red <= origR + threshold && 
     green >= origG - threshold && green <= origG + threshold && 
     blue >= origB - threshold && blue <= origB + threshold) { 
     rawData[byteIndex + 3] = alpha * 255; 
     rawData[byteIndex ] = swapR * alpha; 
     rawData[byteIndex + 1] = swapG * alpha; 
     rawData[byteIndex + 2] = swapB * alpha; 
    } 

    byteIndex += bytesPerPixel; 
} 

CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, rawData, width*height*4, NULL); 

CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB(); 

CGBitmapInfo bitmapInfo = 
kCGBitmapByteOrderDefault | kCGImageAlphaLast; 

CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault; 
CGImageRef imageRef2 = CGImageCreate(width, height, 8, 32, 4*width,colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent); 

UIImage *newImage = [UIImage imageWithCGImage:imageRef2]; 

return newImage; 
} 

@end