C # conversion between RGB and HSB,

C # conversion between RGB and HSB,
Background

In a recent project, you can set any color to obtain two colors: Deep and light. That is to say, the two colors of the same color are used. The first thing that comes to mind is to adjust transparency, but the effect is not ideal. Later, I tried to adjust the color brightness and found that this is the correct solution. However, in. NET, the brightness of the Color cannot be directly changed. You need to convert the Color to the HSB mode, and then change the value of B to adjust the brightness. After adjusting the brightness, you need to switch to the familiar RGB mode. The following shows the color conversion method.

 

Code

1 /// <summary> 2 // color conversion help class 3 /// </summary> 4 public class ColorConversionHelper 5 {6 /// <summary> 7 /// convert RGB to HSB 8 /// </summary> 9 /// <param name = "red"> red value </param> 10 /// <param name = "green"> green value </param> 11 /// <param name = "blue"> blue value </param> 12 /// <returns> return: HSB value set </returns> 13 public static List <float> RGBtoHSB (int red, int green, int blue) 14 {15 List <float> hsbList = new List <float> (); 16 System. drawing. color dColor = System. drawing. color. fromArgb (red, green, blue); 17 hsbList. add (dColor. getHue (); 18 hsbList. add (dColor. getSaturation (); 19 hsbList. add (dColor. getBrightness (); 20 return hsbList; 21} 22 23 24 // <summary> 25 // convert HSB to RGB26 /// </summary> 27 /// <param name = "hue"> tone </ param> 28 // <param name = "saturation"> saturation </param> 29 // <param name = "brightness"> brightness </param> 30 /// <returns> return: color </returns> 31 public static Color HSBtoRGB (float hue, float saturation, float brightness) 32 {33 int r = 0, g = 0, B = 0; 34 if (saturation = 0) 35 {36 r = g = B = (int) (brightness * 255.0f + 0.5f ); 37} 38 else39 {40 float h = (hue-(float) Math. floor (hue) * 6.0f; 41 float f = h-(float) Math. floor (h); 42 float p = brightness * (1.0f-saturation); 43 float q = brightness * (1.0f-saturation * f ); 44 float t = brightness * (1.0f-(saturation * (1.0f-f); 45 switch (int) h) 46 {47 case 0: 48 r = (int) (brightness * 255.0f + 0.5f); 49g = (int) (t * 255.0f + 0.5f); 50 B = (int) (p * 255.0f + 0.5f); 51 break; 52 case :53 r = (int) (q * 255.0f + 0.5f); 54g = (int) (brightness * 255.0f + 0.5f); 55 B = (int) (p * 255.0f + 0.5f); 56 break; 57 case 2: 58 r = (int) (p * 255.0f + 0.5f); 59g = (int) (brightness * 255.0f + 0.5f); 60 B = (int) (t * 255.0f + 0.5f); 61 break; 62 case 3: 63 r = (int) (p * 255.0f + 0.5f); 64g = (int) (q * 255.0f + 0.5f); 65 B = (int) (brightness * 255.0f + 0.5f); 66 break; 67 case 4: 68 r = (int) (t * 255.0f + 0.5f); 69g = (int) (p * 255.0f + 0.5f); 70 B = (int) (brightness * 255.0f + 0.5f); 71 break; 72 case 5: 73 r = (int) (brightness * 255.0f + 0.5f); 74g = (int) (p * 255.0f + 0.5f); 75 B = (int) (q * 255.0f + 0.5f); 76 break; 77} 78} 79 return Color. fromArgb (Convert. toByte (255), Convert. toByte (r), Convert. toByte (g), Convert. toByte (B); 80} 81}

 

 

Additional reading

Http://stackoverflow.com/questions/4106363/converting-rgb-to-hsb-colors

Http://my.oschina.net/soitravel/blog/79862