git.sesse.net Git - casparcg/blob - core/consumer/cadence_guard.cpp

   1 #include "../stdafx.h"\r
   2 \r
   3 #include "cadence_guard.h"\r
   4 \r
   5 #include "frame_consumer.h"\r
   6 \r
   7 #include <common/env.h>\r
   8 #include <common/memory/safe_ptr.h>\r
   9 #include <common/except.h>\r
  10 \r
  11 #include <core/video_format.h>\r
  12 #include <core/frame/data_frame.h>\r
  13 \r
  14 namespace caspar { namespace core {\r
  15 \r
  16 // This class is used to guarantee that audio cadence is correct. This is important for NTSC audio.\r
  17 class cadence_guard : public frame_consumer\r
  18 {\r
  19         safe_ptr<frame_consumer>                consumer_;\r
  20         std::vector<int>                                audio_cadence_;\r
  21         boost::circular_buffer<int>     sync_buffer_;\r
  22 public:\r
  23         cadence_guard(const safe_ptr<frame_consumer>& consumer)\r
  24                 : consumer_(consumer)\r
  25         {\r
  26         }\r
  27         \r
  28         virtual void initialize(const video_format_desc& format_desc, int channel_index) override\r
  29         {\r
  30                 audio_cadence_  = format_desc.audio_cadence;\r
  31                 sync_buffer_    = boost::circular_buffer<int>(format_desc.audio_cadence.size());\r
  32                 consumer_->initialize(format_desc, channel_index);\r
  33         }\r
  34 \r
  35         virtual bool send(const safe_ptr<const data_frame>& frame) override\r
  36         {               \r
  37                 if(audio_cadence_.size() == 1)\r
  38                         return consumer_->send(frame);\r
  39 \r
  40                 bool result = true;\r
  41                 \r
  42                 if(boost::range::equal(sync_buffer_, audio_cadence_) && audio_cadence_.front() == static_cast<int>(frame->audio_data().size())) \r
  43                 {       \r
  44                         // Audio sent so far is in sync, now we can send the next chunk.\r
  45                         result = consumer_->send(frame);\r
  46                         boost::range::rotate(audio_cadence_, std::begin(audio_cadence_)+1);\r
  47                 }\r
  48                 else\r
  49                         CASPAR_LOG(trace) << print() << L" Syncing audio.";\r
  50 \r
  51                 sync_buffer_.push_back(static_cast<int>(frame->audio_data().size()));\r
  52                 \r
  53                 return result;\r
  54         }\r
  55 \r
  56         virtual std::wstring print() const override\r
  57         {\r
  58                 return consumer_->print();\r
  59         }\r
  60 \r
  61         virtual boost::property_tree::wptree info() const override\r
  62         {\r
  63                 return consumer_->info();\r
  64         }\r
  65 \r
  66         virtual bool has_synchronization_clock() const override\r
  67         {\r
  68                 return consumer_->has_synchronization_clock();\r
  69         }\r
  70 \r
  71         virtual int buffer_depth() const override\r
  72         {\r
  73                 return consumer_->buffer_depth();\r
  74         }\r
  75 \r
  76         virtual int index() const override\r
  77         {\r
  78                 return consumer_->index();\r
  79         }\r
  80 };\r
  81 \r
  82 safe_ptr<frame_consumer> create_consumer_cadence_guard(const safe_ptr<frame_consumer>& consumer)\r
  83 {\r
  84         return make_safe<cadence_guard>(std::move(consumer));\r
  85 }\r
  86 \r
  87 }}