MPD  0.20.6
PcmDither.hxx
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19 
20 #ifndef MPD_PCM_DITHER_HXX
21 #define MPD_PCM_DITHER_HXX
22 
23 #include <stdint.h>
24 
25 enum class SampleFormat : uint8_t;
26 
27 class PcmDither {
28  int32_t error[3];
29  int32_t random;
30 
31 public:
32  constexpr PcmDither()
33  :error{0, 0, 0}, random(0) {}
34 
44  template<typename ST, unsigned SBITS, unsigned DBITS>
45  ST DitherShift(ST sample);
46 
47  void Dither24To16(int16_t *dest, const int32_t *src,
48  const int32_t *src_end);
49 
50  void Dither32To16(int16_t *dest, const int32_t *src,
51  const int32_t *src_end);
52 
53 private:
64  template<typename T, T MIN, T MAX, unsigned scale_bits>
65  T Dither(T sample);
66 
75  template<typename ST, typename DT>
76  typename DT::value_type DitherConvert(typename ST::value_type sample);
77 
78  template<typename ST, typename DT>
79  void DitherConvert(typename DT::pointer_type dest,
80  typename ST::const_pointer_type src,
81  typename ST::const_pointer_type src_end);
82 };
83 
84 #endif
void Dither32To16(int16_t *dest, const int32_t *src, const int32_t *src_end)
void Dither24To16(int16_t *dest, const int32_t *src, const int32_t *src_end)
SampleFormat
constexpr PcmDither()
Definition: PcmDither.hxx:32
ST DitherShift(ST sample)
Shift the given sample by #SBITS-#DBITS to the right, and apply dithering.