quantization.hpp

#ifndef PASTELSYS_QUANTIZATION_HPP
#define PASTELSYS_QUANTIZATION_HPP

#include "pastel/sys/math/quantization.h"

namespace Pastel
{

    inline integer quantizeUnsigned(real64 x, integer numbers)
    {
        return (integer)clamp((integer)(x * numbers), 0, numbers - 1);
    }

    inline real64 dequantizeUnsignedMatchEnds(integer x, integer numbers)
    {
        return clamp((real64)x / (numbers - 1), 0, 1);
    }

    inline real64 dequantizeUnsigned(integer x, integer numbers)
    {
        return clamp((((real64)x) + 0.5) / numbers, 0, 1);
    }

    template <integer N>
    inline real64 dequantizeSigned(integer i)
    {
        PASTEL_STATIC_ASSERT(N >= 2 && N <= 32);

        static constexpr int Half = (1 << (N - 1)) - 1;

        return clamp((real64)i / Half, -1, 1);
    }

    /*
   template <integer N>
   inline real64 ditheredQuantizeSigned(integer i)
   {
       PASTEL_STATIC_ASSERT(N >= 2 && N <= 32);

       static constexpr int Half = (1 << (N - 1)) - 1;
       
       real64 dither = random<real64>();
       if (i <= -Half)
       {
           dither = 0;
       }
       if (i >= Half)
       {
           dither = 1;
       }
       
       return clamp((real64)(i + dither) / (Half + 1), -1, 1);
   }
   */

    template <integer N>
    inline integer quantizeSigned(real64 r)
    {
        PASTEL_STATIC_ASSERT(N >= 2 && N <= 32);

        static constexpr int Half = (1 << (N - 1)) - 1;

        return (integer)clamp(std::floor(r * Half + (r + 1) / 2), -Half, Half);
    }

}

#endif