Image ColorConvert::apply(Image im, string from, string to) {
// check for the trivial case
assert(from != to, "color conversion from %s to %s is pointless\n", from.c_str(), to.c_str());
// unsupported destination color spaces
if (to == "yuyv" ||
to == "uyvy") {
panic("Unsupported destination color space: %s\n", to.c_str());
}
// direct conversions that don't have to go via rgb
if (from == "yuyv" && to == "yuv") {
return yuyv2yuv(im);
} else if (from == "uyvy" && to == "yuv") {
return uyvy2yuv(im);
} else if (from == "xyz" && to == "lab") {
return xyz2lab(im);
} else if (from == "lab" && to == "xyz") {
return lab2xyz(im);
} else if (from == "argb" && to == "xyz") {
return argb2xyz(im);
} else if (from == "xyz" && to == "argb") {
return xyz2argb(im);
} else if (from != "rgb" && to != "rgb") {
// conversions that go through rgb
Image halfway = apply(im, from, "rgb");
return apply(halfway, "rgb", to);
} else if (from == "rgb") { // from rgb
if (to == "hsv" || to == "hsl" || to == "hsb") {
return rgb2hsv(im);
} else if (to == "yuv") {
return rgb2yuv(im);
} else if (to == "xyz") {
return rgb2xyz(im);
} else if (to == "y" || to == "gray" ||
to == "grayscale" || to == "luminance") {
return rgb2y(im);
} else if (to == "lab") {
return rgb2lab(im);
} else if (to == "argb") {
return rgb2argb(im);
} else {
panic("Unknown color space %s\n", to.c_str());
}
} else { //(to == "rgb")
if (from == "hsv" || from == "hsl" || from == "hsb") {
return hsv2rgb(im);
} else if (from == "yuv") {
return yuv2rgb(im);
} else if (from == "xyz") {
return xyz2rgb(im);
} else if (from == "y" || from == "gray" ||
from == "grayscale" || from == "luminance") {
return y2rgb(im);
} else if (from == "lab") {
return lab2rgb(im);
} else if (from == "uyvy") {
return uyvy2rgb(im);
} else if (from == "yuyv") {
return yuyv2rgb(im);
} else if (from == "argb") {
return argb2rgb(im);
} else {
panic("Unknown color space %s\n", from.c_str());
}
}
// keep the compiler happy
return Image();
}
Image ColorConvert::rgb2lab(Image im) {
assert(im.channels == 3, "Image does not have 3 channels\n");
return xyz2lab(rgb2xyz(im));
}
double *rgb2lab(double arr[]) {
double *xyz = rgb2xyz(arr);
double *lab = xyz2lab(xyz);
free(xyz);
return lab;
}
