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#include "StarImage.hpp"
#include "StarImageScaling.hpp"
#include "StarInterpolation.hpp"
namespace Star {
Image scaleNearest(Image const& srcImage, Vec2F const& scale) {
Vec2U srcSize = srcImage.size();
Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
destSize[0] = max(destSize[0], 1u);
destSize[1] = max(destSize[1], 1u);
Image destImage(destSize, srcImage.pixelFormat());
for (unsigned y = 0; y < destSize[1]; ++y) {
for (unsigned x = 0; x < destSize[0]; ++x)
destImage.set({x, y}, srcImage.clamp(Vec2I::round(vdiv(Vec2F(x, y), scale))));
}
return destImage;
}
Image scaleBilinear(Image const& srcImage, Vec2F const& scale) {
Vec2U srcSize = srcImage.size();
Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
destSize[0] = max(destSize[0], 1u);
destSize[1] = max(destSize[1], 1u);
Image destImage(destSize, srcImage.pixelFormat());
for (unsigned y = 0; y < destSize[1]; ++y) {
for (unsigned x = 0; x < destSize[0]; ++x) {
auto pos = vdiv(Vec2F(x, y), scale);
auto ipart = Vec2I::floor(pos);
auto fpart = pos - Vec2F(ipart);
auto result = lerp(fpart[1], lerp(fpart[0], Vec4F(srcImage.clamp(ipart[0], ipart[1])), Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1]))), lerp(fpart[0], Vec4F(srcImage.clamp(ipart[0], ipart[1] + 1)), Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1] + 1))));
destImage.set({x, y}, Vec4B(result));
}
}
return destImage;
}
Image scaleBicubic(Image const& srcImage, Vec2F const& scale) {
Vec2U srcSize = srcImage.size();
Vec2U destSize = Vec2U::round(vmult(Vec2F(srcSize), scale));
destSize[0] = max(destSize[0], 1u);
destSize[1] = max(destSize[1], 1u);
Image destImage(destSize, srcImage.pixelFormat());
for (unsigned y = 0; y < destSize[1]; ++y) {
for (unsigned x = 0; x < destSize[0]; ++x) {
auto pos = vdiv(Vec2F(x, y), scale);
auto ipart = Vec2I::floor(pos);
auto fpart = pos - Vec2F(ipart);
Vec4F a = cubic4(fpart[0],
Vec4F(srcImage.clamp(ipart[0], ipart[1])),
Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1])),
Vec4F(srcImage.clamp(ipart[0] + 2, ipart[1])),
Vec4F(srcImage.clamp(ipart[0] + 3, ipart[1])));
Vec4F b = cubic4(fpart[0],
Vec4F(srcImage.clamp(ipart[0], ipart[1] + 1)),
Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1] + 1)),
Vec4F(srcImage.clamp(ipart[0] + 2, ipart[1] + 1)),
Vec4F(srcImage.clamp(ipart[0] + 3, ipart[1] + 1)));
Vec4F c = cubic4(fpart[0],
Vec4F(srcImage.clamp(ipart[0], ipart[1] + 2)),
Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1] + 2)),
Vec4F(srcImage.clamp(ipart[0] + 2, ipart[1] + 2)),
Vec4F(srcImage.clamp(ipart[0] + 3, ipart[1] + 2)));
Vec4F d = cubic4(fpart[0],
Vec4F(srcImage.clamp(ipart[0], ipart[1] + 3)),
Vec4F(srcImage.clamp(ipart[0] + 1, ipart[1] + 3)),
Vec4F(srcImage.clamp(ipart[0] + 2, ipart[1] + 3)),
Vec4F(srcImage.clamp(ipart[0] + 3, ipart[1] + 3)));
auto result = cubic4(fpart[1], a, b, c, d);
destImage.set({x, y}, Vec4B(
clamp(result[0], 0.0f, 255.0f),
clamp(result[1], 0.0f, 255.0f),
clamp(result[2], 0.0f, 255.0f),
clamp(result[3], 0.0f, 255.0f)
));
}
}
return destImage;
}
}
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