streamtools/rescalers/linear-separable.hpp

   1 #ifndef _rescalers__linear_separable__hpp__included__
   2 #define _rescalers__linear_separable__hpp__included__
   3
   4 #include "rescalers/factory.hpp"
   5 #include "bound-method.hpp"
   6
   7 #define MAXCOEFFICIENTS 256
   8
   9 typedef signed long long position_t;
  10
  11 typedef bound_method<void, float*, position_t, position_t, position_t, position_t, unsigned&, unsigned&>
  12         bound_coeff_function_t;
  13
  14
  15 class rescaler_linear_separable : public rescaler
  16 {
  17 public:
  18         void operator()(uint8_t* target, uint32_t twidth, uint32_t theight,
  19                 const uint8_t* source, uint32_t swidth, uint32_t sheight);
  20 protected:
  21         //Fill coeffs, base and coeffcount. Coeffs is set of floating-point coefficients for pixels
  22         //starting from pixel number base (zero-based) and numbering coeffcount. Take care not to refer
  23         //to pixel outside range [0,width). Twidth is target width.
  24         //num / denum gives position of pixel being approximated. The coordinate range is [0, width),
  25         //width giving the width of original data.
  26         virtual void compute_coeffs(float* coeffs, position_t num, position_t denum, position_t width,
  27                 position_t twidth, unsigned& base, unsigned& coeffcount) = 0;
  28 };
  29
  30 class simple_rescaler_linear_separable : public rescaler_factory
  31 {
  32 public:
  33         simple_rescaler_linear_separable(const std::string& type, bound_coeff_function_t _coeffs_fn);
  34         rescaler& make(const std::string& type);
  35 private:
  36         bound_coeff_function_t coeffs_fn;
  37 };
  38
  39 #endif