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2.1.0: Restructured "frame" folder.
[casparcg] / core / mixer / audio / audio_mixer.cpp
1 /*\r
2 * Copyright (c) 2011 Sveriges Television AB <info@casparcg.com>\r
3 *\r
4 * This file is part of CasparCG (www.casparcg.com).\r
5 *\r
6 * CasparCG is free software: you can redistribute it and/or modify\r
7 * it under the terms of the GNU General Public License as published by\r
8 * the Free Software Foundation, either version 3 of the License, or\r
9 * (at your option) any later version.\r
10 *\r
11 * CasparCG is distributed in the hope that it will be useful,\r
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of\r
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
14 * GNU General Public License for more details.\r
15 *\r
16 * You should have received a copy of the GNU General Public License\r
17 * along with CasparCG. If not, see <http://www.gnu.org/licenses/>.\r
18 *\r
19 * Author: Robert Nagy, ronag89@gmail.com\r
20 */\r
21 \r
22 #include "../../stdafx.h"\r
23 \r
24 #include "audio_mixer.h"\r
25 \r
26 #include <core/mixer/write_frame.h>\r
27 #include <core/frame/frame_transform.h>\r
28 #include <common/diagnostics/graph.h>\r
29 \r
30 #include <boost/range/adaptors.hpp>\r
31 #include <boost/range/distance.hpp>\r
32 \r
33 #include <map>\r
34 #include <stack>\r
35 #include <vector>\r
36 \r
37 namespace caspar { namespace core {\r
38 \r
39 struct audio_item\r
40 {\r
41         const void*                     tag;\r
42         frame_transform         transform;\r
43         audio_buffer            audio_data;\r
44 \r
45         audio_item()\r
46         {\r
47         }\r
48 \r
49         audio_item(audio_item&& other)\r
50                 : tag(std::move(other.tag))\r
51                 , transform(std::move(other.transform))\r
52                 , audio_data(std::move(other.audio_data))\r
53         {\r
54         }\r
55 };\r
56 \r
57 typedef std::vector<float, tbb::cache_aligned_allocator<float>> audio_buffer_ps;\r
58         \r
59 struct audio_stream\r
60 {\r
61         frame_transform         prev_transform;\r
62         audio_buffer_ps         audio_data;\r
63 };\r
64 \r
65 struct audio_mixer::impl : boost::noncopyable\r
66 {\r
67         std::stack<core::frame_transform>       transform_stack_;\r
68         std::map<const void*, audio_stream>     audio_streams_;\r
69         std::vector<audio_item>                         items_;\r
70         std::vector<int>                                        audio_cadence_;\r
71         video_format_desc                                       format_desc_;\r
72         \r
73 public:\r
74         impl()\r
75         {\r
76                 transform_stack_.push(core::frame_transform());\r
77         }\r
78         \r
79         void begin(core::draw_frame& frame)\r
80         {\r
81                 transform_stack_.push(transform_stack_.top()*frame.get_frame_transform());\r
82         }\r
83 \r
84         void visit(core::write_frame& frame)\r
85         {\r
86                 if(transform_stack_.top().volume < 0.002 || frame.audio_data().empty())\r
87                         return;\r
88 \r
89                 audio_item item;\r
90                 item.tag                = frame.tag();\r
91                 item.transform  = transform_stack_.top();\r
92                 item.audio_data = std::move(frame.audio_data()); // Note: We don't need to care about upper/lower since audio_data is removed/moved from the last field.\r
93                 \r
94                 items_.push_back(std::move(item));              \r
95         }\r
96 \r
97         void begin(const core::frame_transform& transform)\r
98         {\r
99                 transform_stack_.push(transform_stack_.top()*transform);\r
100         }\r
101                 \r
102         void end()\r
103         {\r
104                 transform_stack_.pop();\r
105         }\r
106         \r
107         audio_buffer mix(const video_format_desc& format_desc)\r
108         {       \r
109                 if(format_desc_ != format_desc)\r
110                 {\r
111                         audio_streams_.clear();\r
112                         audio_cadence_ = format_desc.audio_cadence;\r
113                         format_desc_ = format_desc;\r
114                 }               \r
115                 \r
116                 std::map<const void*, audio_stream>     next_audio_streams;\r
117 \r
118                 BOOST_FOREACH(auto& item, items_)\r
119                 {                       \r
120                         audio_buffer_ps next_audio;\r
121 \r
122                         auto next_transform = item.transform;\r
123                         auto prev_transform = next_transform;\r
124 \r
125                         const auto it = audio_streams_.find(item.tag);\r
126                         if(it != audio_streams_.end())\r
127                         {       \r
128                                 prev_transform  = it->second.prev_transform;\r
129                                 next_audio              = std::move(it->second.audio_data);\r
130                         }\r
131                                                 \r
132                         const float prev_volume = static_cast<float>(prev_transform.volume);\r
133                         const float next_volume = static_cast<float>(next_transform.volume);\r
134                                                                         \r
135                         auto alpha = (next_volume-prev_volume)/static_cast<float>(item.audio_data.size()/format_desc.audio_channels);\r
136                         \r
137                         for(size_t n = 0; n < item.audio_data.size(); ++n)\r
138                                 next_audio.push_back(item.audio_data[n] * (prev_volume + (n/format_desc_.audio_channels) * alpha));\r
139                                                                                 \r
140                         next_audio_streams[item.tag].prev_transform  = std::move(next_transform); // Store all active tags, inactive tags will be removed at the end.\r
141                         next_audio_streams[item.tag].audio_data          = std::move(next_audio);                       \r
142                 }                               \r
143 \r
144                 items_.clear();\r
145 \r
146                 audio_streams_ = std::move(next_audio_streams);\r
147                 \r
148                 if(audio_streams_.empty())              \r
149                         audio_streams_[nullptr].audio_data = audio_buffer_ps(audio_cadence_.front(), 0.0f);\r
150                                 \r
151                 { // sanity check\r
152 \r
153                         auto nb_invalid_streams = boost::count_if(audio_streams_ | boost::adaptors::map_values, [&](const audio_stream& x)\r
154                         {\r
155                                 return x.audio_data.size() < audio_cadence_.front();\r
156                         });\r
157 \r
158                         if(nb_invalid_streams > 0)              \r
159                                 CASPAR_LOG(trace) << "[audio_mixer] Incorrect frame audio cadence detected.";                   \r
160                 }\r
161 \r
162                 std::vector<float> result_ps(audio_cadence_.front(), 0.0f);\r
163                 BOOST_FOREACH(auto& stream, audio_streams_ | boost::adaptors::map_values)\r
164                 {\r
165                         //CASPAR_LOG(debug) << stream.audio_data.size() << L" : " << result_ps.size();\r
166 \r
167                         if(stream.audio_data.size() < result_ps.size())\r
168                         {\r
169                                 stream.audio_data.resize(result_ps.size(), 0.0f);\r
170                                 CASPAR_LOG(trace) << L"[audio_mixer] Appended zero samples";\r
171                         }\r
172 \r
173                         auto out = boost::range::transform(result_ps, stream.audio_data, std::begin(result_ps), std::plus<float>());\r
174                         stream.audio_data.erase(std::begin(stream.audio_data), std::begin(stream.audio_data) + std::distance(std::begin(result_ps), out));\r
175                 }               \r
176                 \r
177                 boost::range::rotate(audio_cadence_, std::begin(audio_cadence_)+1);\r
178                 \r
179                 audio_buffer result;\r
180                 result.reserve(result_ps.size());\r
181                 boost::range::transform(result_ps, std::back_inserter(result), [](float sample){return static_cast<int32_t>(sample);});         \r
182                 \r
183                 return result;\r
184         }\r
185 };\r
186 \r
187 audio_mixer::audio_mixer() : impl_(new impl()){}\r
188 void audio_mixer::begin(core::draw_frame& frame){impl_->begin(frame);}\r
189 void audio_mixer::visit(core::write_frame& frame){impl_->visit(frame);}\r
190 void audio_mixer::end(){impl_->end();}\r
191 audio_buffer audio_mixer::operator()(const video_format_desc& format_desc){return impl_->mix(format_desc);}\r
192 \r
193 }}