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

   1 /*
   2 * Copyright (c) 2011 Sveriges Television AB <info@casparcg.com>
   3 *
   4 * This file is part of CasparCG (www.casparcg.com).
   5 *
   6 * CasparCG is free software: you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation, either version 3 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * CasparCG is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with CasparCG. If not, see <http://www.gnu.org/licenses/>.
  18 *
  19 * Author: Robert Nagy, ronag89@gmail.com
  20 */
  21
  22 #include "../../StdAfx.h"
  23
  24 #include "audio_decoder.h"
  25
  26 #include "../util/util.h"
  27 #include "../input/input.h"
  28 #include "../../ffmpeg_error.h"
  29
  30 #include <core/video_format.h>
  31
  32 #include <common/log.h>
  33 #include <common/cache_aligned_vector.h>
  34
  35 #include <queue>
  36
  37 #if defined(_MSC_VER)
  38 #pragma warning (push)
  39 #pragma warning (disable : 4244)
  40 #endif
  41 extern "C"
  42 {
  43         #include <libavformat/avformat.h>
  44         #include <libavcodec/avcodec.h>
  45         #include <libswresample/swresample.h>
  46 }
  47 #if defined(_MSC_VER)
  48 #pragma warning (pop)
  49 #endif
  50
  51 namespace caspar { namespace ffmpeg {
  52
  53 uint64_t get_channel_layout(AVCodecContext* dec)
  54 {
  55         auto layout = (dec->channel_layout && dec->channels == av_get_channel_layout_nb_channels(dec->channel_layout)) ? dec->channel_layout : av_get_default_channel_layout(dec->channels);
  56         return layout;
  57 }
  58
  59 struct audio_decoder::impl : boost::noncopyable
  60 {
  61         core::monitor::subject                                                                          monitor_subject_;
  62         input*                                                                                                          input_;
  63         int                                                                                                                     index_;
  64         const core::video_format_desc                                                           format_desc_;
  65         const spl::shared_ptr<AVCodecContext>                                           codec_context_ = open_codec(input_->context(), AVMEDIA_TYPE_AUDIO, index_);
  66
  67         std::shared_ptr<SwrContext>                                                                     swr_                            {
  68                                                                                                                                                                                 swr_alloc_set_opts(
  69                                                                                                                                                                                                 nullptr,
  70                                                                                                                                                                                                 av_get_default_channel_layout(format_desc_.audio_channels),
  71                                                                                                                                                                                                 AV_SAMPLE_FMT_S32,
  72                                                                                                                                                                                                 format_desc_.audio_sample_rate,
  73                                                                                                                                                                                                 get_channel_layout(codec_context_.get()),
  74                                                                                                                                                                                                 codec_context_->sample_fmt,
  75                                                                                                                                                                                                 codec_context_->sample_rate,
  76                                                                                                                                                                                                 0,
  77                                                                                                                                                                                                 nullptr),
  78                                                                                                                                                                                 [](SwrContext* p){swr_free(&p); }
  79                                                                                                                                                                         };
  80
  81         cache_aligned_vector<uint8_t>                                                           buffer_;
  82
  83         std::shared_ptr<AVPacket>                                                                       current_packet_;
  84
  85 public:
  86         explicit impl(input& in, const core::video_format_desc& format_desc)
  87                 : input_(&in)
  88                 , format_desc_(format_desc)
  89                 , codec_context_(open_codec(input_->context(), AVMEDIA_TYPE_AUDIO, index_))
  90                 , buffer_(480000 * 4)
  91         {
  92                 if(!swr_)
  93                         CASPAR_THROW_EXCEPTION(bad_alloc());
  94
  95                 THROW_ON_ERROR2(swr_init(swr_.get()), "[audio_decoder]");
  96         }
  97
  98         std::shared_ptr<AVFrame> poll()
  99         {
 100                 if(!current_packet_ && !input_->try_pop_audio(current_packet_))
 101                         return nullptr;
 102
 103                 std::shared_ptr<AVFrame> audio;
 104
 105                 if(!current_packet_)
 106                 {
 107                         avcodec_flush_buffers(codec_context_.get());
 108                 }
 109                 else if(!current_packet_->data)
 110                 {
 111                         if(codec_context_->codec->capabilities & CODEC_CAP_DELAY)
 112                                 audio = decode(*current_packet_);
 113
 114                         if(!audio)
 115                                 current_packet_.reset();
 116                 }
 117                 else
 118                 {
 119                         audio = decode(*current_packet_);
 120
 121                         if(current_packet_->size == 0)
 122                                 current_packet_.reset();
 123                 }
 124
 125                 return audio ? audio : poll();
 126         }
 127
 128         std::shared_ptr<AVFrame> decode(AVPacket& pkt)
 129         {
 130                 auto frame = create_frame();
 131
 132                 int got_frame = 0;
 133                 auto len = THROW_ON_ERROR2(avcodec_decode_audio4(codec_context_.get(), frame.get(), &got_frame, &pkt), "[audio_decoder]");
 134
 135                 if(len == 0)
 136                 {
 137                         pkt.size = 0;
 138                         return nullptr;
 139                 }
 140
 141         pkt.data += len;
 142         pkt.size -= len;
 143
 144                 if(!got_frame)
 145                         return nullptr;
 146
 147                 const uint8_t *in[] = {frame->data[0]};
 148                 uint8_t* out[]          = {buffer_.data()};
 149
 150                 auto channel_samples = swr_convert(swr_.get(),
 151                                                                                         out, static_cast<int>(buffer_.size()) / format_desc_.audio_channels / av_get_bytes_per_sample(AV_SAMPLE_FMT_S32),
 152                                                                                         in, frame->nb_samples);
 153
 154                 frame->data[0]          = buffer_.data();
 155                 frame->linesize[0]      = channel_samples * format_desc_.audio_channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S32);
 156                 frame->nb_samples       = channel_samples;
 157                 frame->format           = AV_SAMPLE_FMT_S32;
 158
 159                 monitor_subject_  << core::monitor::message("/file/audio/sample-rate")  % codec_context_->sample_rate
 160                                                 << core::monitor::message("/file/audio/channels")       % codec_context_->channels
 161                                                 << core::monitor::message("/file/audio/format")         % u8(av_get_sample_fmt_name(codec_context_->sample_fmt))
 162                                                 << core::monitor::message("/file/audio/codec")          % u8(codec_context_->codec->long_name);
 163
 164                 return frame;
 165         }
 166
 167         uint32_t nb_frames() const
 168         {
 169                 return 0;
 170         }
 171
 172         std::wstring print() const
 173         {
 174                 return L"[audio-decoder] " + u16(codec_context_->codec->long_name);
 175         }
 176 };
 177
 178 audio_decoder::audio_decoder(input& input, const core::video_format_desc& format_desc) : impl_(new impl(input, format_desc)){}
 179 audio_decoder::audio_decoder(audio_decoder&& other) : impl_(std::move(other.impl_)){}
 180 audio_decoder& audio_decoder::operator=(audio_decoder&& other){impl_ = std::move(other.impl_); return *this;}
 181 std::shared_ptr<AVFrame> audio_decoder::operator()(){return impl_->poll();}
 182 uint32_t audio_decoder::nb_frames() const{return impl_->nb_frames();}
 183 std::wstring audio_decoder::print() const{return impl_->print();}
 184 core::monitor::subject& audio_decoder::monitor_output() { return impl_->monitor_subject_;}
 185 }}