git.sesse.net Git - casparcg/blob - modules/ffmpeg/producer/audio/audio_decoder.cpp

   1 /*\r
   2 * copyright (c) 2010 Sveriges Television AB <info@casparcg.com>\r
   3 *\r
   4 *  This file is part of CasparCG.\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 */\r
  20 #include "../../stdafx.h"\r
  21 \r
  22 #include "audio_decoder.h"\r
  23 #include "audio_resampler.h"\r
  24 \r
  25 #include "../util.h"\r
  26 #include "../../ffmpeg_error.h"\r
  27 \r
  28 #include <core/video_format.h>\r
  29 \r
  30 #include <tbb/cache_aligned_allocator.h>\r
  31 \r
  32 #if defined(_MSC_VER)\r
  33 #pragma warning (push)\r
  34 #pragma warning (disable : 4244)\r
  35 #endif\r
  36 extern "C" \r
  37 {\r
  38         #include <libavformat/avformat.h>\r
  39         #include <libavcodec/avcodec.h>\r
  40 }\r
  41 #if defined(_MSC_VER)\r
  42 #pragma warning (pop)\r
  43 #endif\r
  44 \r
  45 namespace caspar { namespace ffmpeg {\r
  46         \r
  47 struct audio_decoder::implementation : public Concurrency::agent, boost::noncopyable\r
  48 {\r
  49         audio_decoder::source_t& source_;\r
  50         audio_decoder::target_t& target_;\r
  51 \r
  52         std::shared_ptr<AVCodecContext>                                                         codec_context_;         \r
  53         const core::video_format_desc                                                           format_desc_;\r
  54         int                                                                                                                     index_;\r
  55         std::unique_ptr<audio_resampler>                                                        resampler_;\r
  56 \r
  57         std::vector<int8_t,  tbb::cache_aligned_allocator<int8_t>>      buffer1_;\r
  58         \r
  59         int64_t                                                                                                         nb_frames_;\r
  60 \r
  61 public:\r
  62         explicit implementation(audio_decoder::source_t& source,\r
  63                                                         audio_decoder::target_t& target,\r
  64                                                         const safe_ptr<AVFormatContext>& context, \r
  65                                                         const core::video_format_desc& format_desc) \r
  66                 : source_(source)\r
  67                 , target_(target)\r
  68                 , format_desc_(format_desc)     \r
  69                 , nb_frames_(0)\r
  70         {                               \r
  71                 \r
  72                 AVCodec* dec;\r
  73                 index_ = THROW_ON_ERROR3(av_find_best_stream(context.get(), AVMEDIA_TYPE_AUDIO, -1, -1, &dec, 0), "[audio_decoder]", ffmpeg_stream_not_found);\r
  74                 CASPAR_VERIFY(index_ > -1, ffmpeg_error());\r
  75 \r
  76                 THROW_ON_ERROR2(avcodec_open(context->streams[index_]->codec, dec), "[audio_decoder]");\r
  77                 CASPAR_VERIFY(context->streams[index_]->codec, ffmpeg_error());\r
  78                         \r
  79                 codec_context_.reset(context->streams[index_]->codec, avcodec_close);\r
  80 \r
  81                 buffer1_.resize(AVCODEC_MAX_AUDIO_FRAME_SIZE*2);\r
  82 \r
  83                 resampler_.reset(new audio_resampler(format_desc_.audio_channels,    codec_context_->channels,\r
  84                                                                                                 format_desc_.audio_sample_rate, codec_context_->sample_rate,\r
  85                                                                                                 AV_SAMPLE_FMT_S32,                               codec_context_->sample_fmt));                  \r
  86                 CASPAR_VERIFY(resampler_, ffmpeg_error());\r
  87 \r
  88                 start();\r
  89         }\r
  90 \r
  91         ~implementation()\r
  92         {\r
  93                 agent::wait(this);\r
  94         }       \r
  95 \r
  96         virtual void run()\r
  97         {\r
  98                 try\r
  99                 {\r
 100                         while(true)\r
 101                         {\r
 102                                 auto packet = Concurrency::receive(source_, [this](const std::shared_ptr<AVPacket>& packet)\r
 103                                 {\r
 104                                         return packet && packet->stream_index == index_;\r
 105                                 });\r
 106 \r
 107                                 if(packet == eof_packet(index_))                                \r
 108                                         break;\r
 109                                 \r
 110                                 if(packet == loop_packet(index_))       \r
 111                                 {       \r
 112                                         avcodec_flush_buffers(codec_context_.get());\r
 113                                         Concurrency::send(target_, loop_audio());\r
 114                                 }       \r
 115                                 else if(packet->stream_index == index_)\r
 116                                 {\r
 117                                         Concurrency::send(target_, decode(*packet));            \r
 118                                         Concurrency::wait(0);\r
 119                                 }\r
 120                         }\r
 121                 }\r
 122                 catch(...)\r
 123                 {\r
 124                         CASPAR_LOG_CURRENT_EXCEPTION();\r
 125                 }\r
 126                 \r
 127                 Concurrency::send(target_, eof_audio());\r
 128 \r
 129                 done();\r
 130         }\r
 131         \r
 132         std::shared_ptr<core::audio_buffer> decode(AVPacket& pkt)\r
 133         {               \r
 134                 buffer1_.resize(AVCODEC_MAX_AUDIO_FRAME_SIZE*2);\r
 135                 int written_bytes = buffer1_.size() - FF_INPUT_BUFFER_PADDING_SIZE;\r
 136                 \r
 137                 int ret = THROW_ON_ERROR2(avcodec_decode_audio3(codec_context_.get(), reinterpret_cast<int16_t*>(buffer1_.data()), &written_bytes, &pkt), "[audio_decoder]");\r
 138 \r
 139                 // There might be several frames in one packet.\r
 140                 pkt.size -= ret;\r
 141                 pkt.data += ret;\r
 142                         \r
 143                 buffer1_.resize(written_bytes);\r
 144 \r
 145                 buffer1_ = resampler_->resample(std::move(buffer1_));\r
 146                 \r
 147                 const auto n_samples = buffer1_.size() / av_get_bytes_per_sample(AV_SAMPLE_FMT_S32);\r
 148                 const auto samples = reinterpret_cast<int32_t*>(buffer1_.data());\r
 149 \r
 150                 return n_samples > 0 ? std::make_shared<core::audio_buffer>(samples, samples + n_samples) : nullptr;\r
 151         }\r
 152 };\r
 153 \r
 154 audio_decoder::audio_decoder(source_t& source,\r
 155                                                          target_t& target,\r
 156                                                          const safe_ptr<AVFormatContext>& context, \r
 157                                                          const core::video_format_desc& format_desc)\r
 158         : impl_(new implementation(source, target, context, format_desc))\r
 159 {\r
 160 }\r
 161 int64_t audio_decoder::nb_frames() const{return impl_->nb_frames_;}\r
 162 \r
 163 }}