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
  34 #include <tbb/cache_aligned_allocator.h>
  35
  36 #include <queue>
  37
  38 #if defined(_MSC_VER)
  39 #pragma warning (push)
  40 #pragma warning (disable : 4244)
  41 #endif
  42 extern "C"
  43 {
  44         #include <libavformat/avformat.h>
  45         #include <libavcodec/avcodec.h>
  46         #include <libswresample/swresample.h>
  47 }
  48 #if defined(_MSC_VER)
  49 #pragma warning (pop)
  50 #endif
  51
  52 namespace caspar { namespace ffmpeg {
  53
  54 uint64_t get_channel_layout(AVCodecContext* dec)
  55 {
  56         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);
  57         return layout;
  58 }
  59
  60 struct audio_decoder::impl : boost::noncopyable
  61 {
  62         core::monitor::subject                                                                          monitor_subject_;
  63         input*                                                                                                          input_;
  64         int                                                                                                                     index_;
  65         const core::video_format_desc                                                           format_desc_;
  66         const spl::shared_ptr<AVCodecContext>                                           codec_context_ = open_codec(input_->context(), AVMEDIA_TYPE_AUDIO, index_);
  67
  68         std::shared_ptr<SwrContext>                                                                     swr_                            {
  69                                                                                                                                                                                 swr_alloc_set_opts(
  70                                                                                                                                                                                                 nullptr,
  71                                                                                                                                                                                                 av_get_default_channel_layout(format_desc_.audio_channels),
  72                                                                                                                                                                                                 AV_SAMPLE_FMT_S32,
  73                                                                                                                                                                                                 format_desc_.audio_sample_rate,
  74                                                                                                                                                                                                 get_channel_layout(codec_context_.get()),
  75                                                                                                                                                                                                 codec_context_->sample_fmt,
  76                                                                                                                                                                                                 codec_context_->sample_rate,
  77                                                                                                                                                                                                 0,
  78                                                                                                                                                                                                 nullptr),
  79                                                                                                                                                                                 [](SwrContext* p){swr_free(&p); }
  80                                                                                                                                                                         };
  81
  82         std::vector<uint8_t, tbb::cache_aligned_allocator<int8_t>>      buffer_;
  83
  84         std::shared_ptr<AVPacket>                                                                       current_packet_;
  85
  86 public:
  87         explicit impl(input& in, const core::video_format_desc& format_desc)
  88                 : input_(&in)
  89                 , format_desc_(format_desc)
  90                 , codec_context_(open_codec(input_->context(), AVMEDIA_TYPE_AUDIO, index_))
  91                 , buffer_(480000 * 4)
  92         {
  93                 if(!swr_)
  94                         CASPAR_THROW_EXCEPTION(bad_alloc());
  95
  96                 THROW_ON_ERROR2(swr_init(swr_.get()), "[audio_decoder]");
  97         }
  98
  99         std::shared_ptr<AVFrame> poll()
 100         {
 101                 if(!current_packet_ && !input_->try_pop_audio(current_packet_))
 102                         return nullptr;
 103
 104                 std::shared_ptr<AVFrame> audio;
 105
 106                 if(!current_packet_)
 107                 {
 108                         avcodec_flush_buffers(codec_context_.get());
 109                 }
 110                 else if(!current_packet_->data)
 111                 {
 112                         if(codec_context_->codec->capabilities & CODEC_CAP_DELAY)
 113                                 audio = decode(*current_packet_);
 114
 115                         if(!audio)
 116                                 current_packet_.reset();
 117                 }
 118                 else
 119                 {
 120                         audio = decode(*current_packet_);
 121
 122                         if(current_packet_->size == 0)
 123                                 current_packet_.reset();
 124                 }
 125
 126                 return audio ? audio : poll();
 127         }
 128
 129         std::shared_ptr<AVFrame> decode(AVPacket& pkt)
 130         {
 131                 auto frame = create_frame();
 132
 133                 int got_frame = 0;
 134                 auto len = THROW_ON_ERROR2(avcodec_decode_audio4(codec_context_.get(), frame.get(), &got_frame, &pkt), "[audio_decoder]");
 135
 136                 if(len == 0)
 137                 {
 138                         pkt.size = 0;
 139                         return nullptr;
 140                 }
 141
 142         pkt.data += len;
 143         pkt.size -= len;
 144
 145                 if(!got_frame)
 146                         return nullptr;
 147
 148                 const uint8_t *in[] = {frame->data[0]};
 149                 uint8_t* out[]          = {buffer_.data()};
 150
 151                 auto channel_samples = swr_convert(swr_.get(),
 152                                                                                         out, static_cast<int>(buffer_.size()) / format_desc_.audio_channels / av_get_bytes_per_sample(AV_SAMPLE_FMT_S32),
 153                                                                                         in, frame->nb_samples);
 154
 155                 frame->data[0]          = buffer_.data();
 156                 frame->linesize[0]      = channel_samples * format_desc_.audio_channels * av_get_bytes_per_sample(AV_SAMPLE_FMT_S32);
 157                 frame->nb_samples       = channel_samples;
 158                 frame->format           = AV_SAMPLE_FMT_S32;
 159
 160                 monitor_subject_  << core::monitor::message("/file/audio/sample-rate")  % codec_context_->sample_rate
 161                                                 << core::monitor::message("/file/audio/channels")       % codec_context_->channels
 162                                                 << core::monitor::message("/file/audio/format")         % u8(av_get_sample_fmt_name(codec_context_->sample_fmt))
 163                                                 << core::monitor::message("/file/audio/codec")          % u8(codec_context_->codec->long_name);
 164
 165                 return frame;
 166         }
 167
 168         uint32_t nb_frames() const
 169         {
 170                 return 0;
 171         }
 172
 173         std::wstring print() const
 174         {
 175                 return L"[audio-decoder] " + u16(codec_context_->codec->long_name);
 176         }
 177 };
 178
 179 audio_decoder::audio_decoder(input& input, const core::video_format_desc& format_desc) : impl_(new impl(input, format_desc)){}
 180 audio_decoder::audio_decoder(audio_decoder&& other) : impl_(std::move(other.impl_)){}
 181 audio_decoder& audio_decoder::operator=(audio_decoder&& other){impl_ = std::move(other.impl_); return *this;}
 182 std::shared_ptr<AVFrame> audio_decoder::operator()(){return impl_->poll();}
 183 uint32_t audio_decoder::nb_frames() const{return impl_->nb_frames();}
 184 std::wstring audio_decoder::print() const{return impl_->print();}
 185 core::monitor::subject& audio_decoder::monitor_output() { return impl_->monitor_subject_;}
 186 }}