我想为Silverlight制作一个像素着色器,它将帮助我使用滑块更改色调/饱和度/亮度。*色调滑块的取值范围为- 180,180*饱和度滑块的取值范围为- 100,100 *亮度滑块的取值范围为-100,100
我设法创建了一个像素着色器,可以操作饱和度和亮度的值。但我能找到任何改变色调值的算法。有人能给我一个算法吗?谢谢。
下面是我的HLSL代码:
/// <summary>The brightness offset.</summary>
/// <minValue>-180</minValue>
/// <maxValue>180</maxValue>
/// <defaultValue>0</defaultValue>
float Hue : register(C0);
/// <summary>The saturation offset.</summary>
/// <minValue>-100</minValue>
/// <maxValue>100</maxValue>
/// <defaultValue>0</defaultValue>
float Saturation : register(C1);
/// <summary>The lightness offset.</summary>
/// <minValue>-100</minValue>
/// <maxValue>100</maxValue>
/// <defaultValue>0</defaultValue>
float Lightness : register(C2);
sampler2D input : register(S0);
//--------------------------------------------------------------------------------------
// Pixel Shader
//--------------------------------------------------------------------------------------
float4 main(float2 uv : TEXCOORD) : COLOR
{
// some vars
float saturation = Saturation / 100 + 1;
float lightness = Lightness / 100;
float3 luminanceWeights = float3(0.299,0.587,0.114);
// input raw pixel
float4 srcPixel = tex2D(input, uv);
// Apply saturation
float luminance = dot(srcPixel, luminanceWeights);
float4 dstPixel = lerp(luminance, srcPixel, saturation);
// Apply lightness
dstPixel.rgb += lightness;
//retain the incoming alpha
dstPixel.a = srcPixel.a;
return dstPixel;
}发布于 2011-01-19 01:56:25
色彩空间之间的转换可以在EasyRGB上找到,请参阅nokola.com上的这篇文章,了解色调偏移的Silverlight实现。如果你采用here中提到的方法,也许可以在一个PS2.0着色器中适应色调、饱和度和亮度,但我没有尝试过。
发布于 2014-05-25 06:05:00
输入域略有不同,但可以很容易地进行调整:
float Hue : register(C0); // 0..360, default 0
float Saturation : register(C1); // 0..2, default 1
float Luminosity : register(C2); // -1..1, default 0
sampler2D input1 : register(S0);
static float3x3 matrixH =
{
0.8164966f, 0, 0.5352037f,
-0.4082483f, 0.70710677f, 1.0548190f,
-0.4082483f, -0.70710677f, 0.1420281f
};
static float3x3 matrixH2 =
{
0.84630f, -0.37844f, -0.37844f,
-0.37265f, 0.33446f, -1.07975f,
0.57735f, 0.57735f, 0.57735f
};
float4 main(float2 uv : TEXCOORD) : COLOR
{
float4 c = tex2D(input1, uv);
float3x3 rotateZ =
{
cos(radians(Hue)), sin(radians(Hue)), 0,
-sin(radians(Hue)), cos(radians(Hue)), 0,
0, 0, 1
};
matrixH = mul(matrixH, rotateZ);
matrixH = mul(matrixH, matrixH2);
float i = 1 - Saturation;
float3x3 matrixS =
{
i*0.3086f+Saturation, i*0.3086f, i*0.3086f,
i*0.6094f, i*0.6094f+Saturation, i*0.6094f,
i*0.0820f, i*0.0820f, i*0.0820f+Saturation
};
matrixH = mul(matrixH, matrixS);
float3 c1 = mul(c, matrixH);
c1 += Luminosity;
return float4(c1, c.a);
}发布于 2013-07-18 19:40:47
https://stackoverflow.com/questions/4726805
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