alc/bformatdec.h

   1 #ifndef BFORMATDEC_H
   2 #define BFORMATDEC_H
   3
   4 #include <array>
   5 #include <cstddef>
   6
   7 #include "AL/al.h"
   8
   9 #include "alcmain.h"
  10 #include "almalloc.h"
  11 #include "alspan.h"
  12 #include "ambidefs.h"
  13 #include "devformat.h"
  14 #include "filters/splitter.h"
  15 #include "vector.h"
  16
  17 struct AmbDecConf;
  18
  19
  20 using ChannelDec = ALfloat[MAX_AMBI_CHANNELS];
  21
  22 class BFormatDec {
  23     static constexpr size_t sHFBand{0};
  24     static constexpr size_t sLFBand{1};
  25     static constexpr size_t sNumBands{2};
  26
  27     bool mDualBand{false};
  28     ALuint mEnabled{0u}; /* Bitfield of enabled channels. */
  29
  30     ALuint mNumChannels{0u};
  31     union MatrixU {
  32         ALfloat Dual[MAX_OUTPUT_CHANNELS][sNumBands][MAX_AMBI_CHANNELS];
  33         ALfloat Single[MAX_OUTPUT_CHANNELS][MAX_AMBI_CHANNELS];
  34     } mMatrix{};
  35
  36     /* NOTE: BandSplitter filters are unused with single-band decoding */
  37     BandSplitter mXOver[MAX_AMBI_CHANNELS];
  38
  39     al::vector<FloatBufferLine, 16> mSamples;
  40     /* These two alias into Samples */
  41     FloatBufferLine *mSamplesHF{nullptr};
  42     FloatBufferLine *mSamplesLF{nullptr};
  43
  44 public:
  45     BFormatDec(const AmbDecConf *conf, const bool allow_2band, const ALuint inchans,
  46         const ALuint srate, const ALuint (&chanmap)[MAX_OUTPUT_CHANNELS]);
  47     BFormatDec(const ALuint inchans, const ALsizei chancount,
  48         const ChannelDec (&chancoeffs)[MAX_OUTPUT_CHANNELS],
  49         const ALuint (&chanmap)[MAX_OUTPUT_CHANNELS]);
  50
  51     /* Decodes the ambisonic input to the given output channels. */
  52     void process(const al::span<FloatBufferLine> OutBuffer, const FloatBufferLine *InSamples,
  53         const size_t SamplesToDo);
  54
  55     /* Retrieves per-order HF scaling factors for "upsampling" ambisonic data. */
  56     static std::array<ALfloat,MAX_AMBI_ORDER+1> GetHFOrderScales(const ALuint in_order,
  57         const ALuint out_order) noexcept;
  58
  59     DEF_NEWDEL(BFormatDec)
  60 };
  61
  62 #endif /* BFORMATDEC_H */