git.sesse.net Git - casparcg/blob - core/mixer/audio/audio_mixer.cpp

   1 #include "../../stdafx.h"\r
   2 \r
   3 #include "audio_mixer.h"\r
   4 \r
   5 namespace caspar { namespace core {\r
   6         \r
   7 audio_transform& audio_transform::operator*=(const audio_transform &other) \r
   8 {\r
   9         gain *= other.gain;\r
  10         return *this;\r
  11 }\r
  12 \r
  13 const audio_transform audio_transform::operator*(const audio_transform &other) const \r
  14 {\r
  15         return audio_transform(*this) *= other;\r
  16 }\r
  17 \r
  18 struct audio_mixer::implementation\r
  19 {\r
  20         std::vector<short> audio_data_;\r
  21         std::stack<audio_transform> transform_stack_;\r
  22 \r
  23 public:\r
  24         implementation()\r
  25         {\r
  26                 transform_stack_.push(audio_transform());\r
  27         }\r
  28 \r
  29         void begin(const audio_transform& transform)\r
  30         {\r
  31                 transform_stack_.push(transform_stack_.top()*transform);\r
  32         }\r
  33 \r
  34         void process(const std::vector<short>& audio_data)\r
  35         {               \r
  36                 if(audio_data_.empty())\r
  37                         audio_data_.resize(audio_data.size(), 0);\r
  38 \r
  39                 tbb::parallel_for\r
  40                 (\r
  41                         tbb::blocked_range<size_t>(0, audio_data.size()),\r
  42                         [&](const tbb::blocked_range<size_t>& r)\r
  43                         {\r
  44                                 for(size_t n = r.begin(); n < r.end(); ++n)\r
  45                                 {\r
  46                                         int sample = static_cast<int>(audio_data[n]);\r
  47                                         sample = (static_cast<int>(transform_stack_.top().gain*8192.0)*sample)/8192;\r
  48                                         audio_data_[n] = static_cast<short>((static_cast<int>(audio_data_[n]) + sample) & 0xFFFF);\r
  49                                 }\r
  50                         }\r
  51                 );\r
  52         }\r
  53 \r
  54         void end()\r
  55         {\r
  56                 transform_stack_.pop();\r
  57         }\r
  58 \r
  59         std::vector<short> begin_pass()\r
  60         {\r
  61                 return std::move(audio_data_);\r
  62         }\r
  63 };\r
  64 \r
  65 audio_mixer::audio_mixer() : impl_(new implementation()){}\r
  66 void audio_mixer::begin(const audio_transform& transform){impl_->begin(transform);}\r
  67 void audio_mixer::process(const std::vector<short>& audio_data){impl_->process(audio_data);}\r
  68 void audio_mixer::end(){impl_->end();}\r
  69 std::vector<short> audio_mixer::begin_pass(){return impl_->begin_pass();}       \r
  70 void audio_mixer::end_pass(){}\r
  71 \r
  72 }}