我正在尝试编写一个函数,该函数可以让我对位图进行红移或蓝移,同时保留图像的整体亮度。基本上,完全红移的位图将具有与原始位图相同的亮度,但会被完全染成红色(即,所有像素的 G 和 B 值都相同)。蓝色着色相同(但 R 和 G 相等)。频谱偏移的程度需要在 0 到 1 之间变化。
提前致谢。
这是我正在寻找的效果(糟糕的JPEG,抱歉):
替代文字 http://www.freeimagehosting.net/uploads/d15ff241ca.jpg
中间的图像是原始图像,侧面图像分别是全红移、部分红移、部分蓝移和全蓝移。
这是产生这种效果的函数:
public void RedBlueShift(Bitmap bmp, double factor)
{
byte R = 0;
byte G = 0;
byte B = 0;
byte Rmax = 0;
byte Gmax = 0;
byte Bmax = 0;
double avg = 0;
double normal = 0;
if (factor > 1)
{
factor = 1;
}
else if (factor < -1)
{
factor = -1;
}
for (int x = 0; x < bmp.Width; x++)
{
for (int y = 0; y < bmp.Height; y++)
{
Color color = bmp.GetPixel(x, y);
R = color.R;
G = color.G;
B = color.B;
avg = (double)(R + G + B) / 3;
normal = avg / 255.0; // to preserve overall intensity
if (factor < 0) // red-tinted:
{
if (normal < .5)
{
Rmax = (byte)((normal / .5) * 255);
Gmax = 0;
Bmax = 0;
}
else
{
Rmax = 255;
Gmax = (byte)(((normal - .5) * 2) * 255);
Bmax = Gmax;
}
R = (byte)((double)R - ((double)(R - Rmax) * -factor));
G = (byte)((double)G - ((double)(G - Gmax) * -factor));
B = (byte)((double)B - ((double)(B - Bmax) * -factor));
}
else if (factor > 0) // blue-tinted:
{
if (normal < .5)
{
Rmax = 0;
Gmax = 0;
Bmax = (byte)((normal / .5) * 255);
}
else
{
Rmax = (byte)(((normal - .5) * 2) * 255);
Gmax = Rmax;
Bmax = 255;
}
R = (byte)((double)R - ((double)(R - Rmax) * factor));
G = (byte)((double)G - ((double)(G - Gmax) * factor));
B = (byte)((double)B - ((double)(B - Bmax) * factor));
}
color = Color.FromArgb(R, G, B);
bmp.SetPixel(x, y, color);
}
}
}
您将为此使用 ColorMatrix 类。这个项目中有一个很好的教程。