32 lines
1.1 KiB
Cython
32 lines
1.1 KiB
Cython
# cython: infer_types=True
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# cython: profile=False
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# cython: boundscheck=False
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# cython: wraparound=False
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cdef inline float clip(float a, float min_value, float max_value) noexcept nogil:
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"""Clip a value between min_value and max_value inclusive."""
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return min(max(a, min_value), max_value)
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cdef inline float3 convert_rgb_to_cam16ucs(float[:, ::1] rgb_to_cam16ucs, float r, float g, float b) noexcept nogil:
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"""Converts floating point (r,g,b) valueto 3-tuple in CAM16UCS colour space, via 24-bit RGB lookup matrix."""
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cdef unsigned int rgb_24bit = (<unsigned int>(r*255) << 16) + (<unsigned int>(g*255) << 8) + <unsigned int>(b*255)
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cdef float3 res
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cdef int i
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for i in range(3):
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res.data[i] = rgb_to_cam16ucs[rgb_24bit][i]
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return res
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cdef inline float colour_distance_squared(float[3] colour1, float[3] colour2) noexcept nogil:
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"""Computes Euclidean squared distance between two floating-point colour 3-tuples."""
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return (
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(colour1[0] - colour2[0]) * (colour1[0] - colour2[0]) +
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(colour1[1] - colour2[1]) * (colour1[1] - colour2[1]) +
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(colour1[2] - colour2[2]) * (colour1[2] - colour2[2])
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)
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