git.sesse.net Git - casparcg/blob - modules/ffmpeg/producer/video/video_decoder.cpp

   1 /*
   2 * Copyright 2013 Sveriges Television AB http://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 "video_decoder.h"
  25
  26 #include "../util/util.h"
  27
  28 #include "../../ffmpeg_error.h"
  29
  30 #include <core/frame/frame_transform.h>
  31 #include <core/frame/frame_factory.h>
  32
  33 #include <boost/range/algorithm_ext/push_back.hpp>
  34 #include <boost/filesystem.hpp>
  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 <libavcodec/avcodec.h>
  45         #include <libavformat/avformat.h>
  46 }
  47 #if defined(_MSC_VER)
  48 #pragma warning (pop)
  49 #endif
  50
  51 namespace caspar { namespace ffmpeg {
  52
  53 struct video_decoder::implementation : boost::noncopyable
  54 {
  55         int                                                                             index_                          = -1;
  56         const spl::shared_ptr<AVCodecContext>   codec_context_;
  57
  58         std::queue<spl::shared_ptr<AVPacket>>   packets_;
  59
  60         const uint32_t                                                  nb_frames_;
  61
  62         const int                                                               width_                          = codec_context_->width;
  63         const int                                                               height_                         = codec_context_->height;
  64         bool                                                                    is_progressive_;
  65
  66         tbb::atomic<uint32_t>                                   file_frame_number_;
  67
  68 public:
  69         explicit implementation(const spl::shared_ptr<AVFormatContext>& context)
  70                 : codec_context_(open_codec(*context, AVMEDIA_TYPE_VIDEO, index_, false))
  71                 , nb_frames_(static_cast<uint32_t>(context->streams[index_]->nb_frames))
  72         {
  73                 file_frame_number_ = 0;
  74
  75                 codec_context_->refcounted_frames = 1;
  76         }
  77
  78         void push(const std::shared_ptr<AVPacket>& packet)
  79         {
  80                 if(!packet)
  81                         return;
  82
  83                 if(packet->stream_index == index_ || packet->data == nullptr)
  84                         packets_.push(spl::make_shared_ptr(packet));
  85         }
  86
  87         std::shared_ptr<AVFrame> poll()
  88         {
  89                 if(packets_.empty())
  90                         return nullptr;
  91
  92                 auto packet = packets_.front();
  93
  94                 if(packet->data == nullptr)
  95                 {
  96                         if(codec_context_->codec->capabilities & CODEC_CAP_DELAY)
  97                         {
  98                                 auto video = decode(packet);
  99                                 if(video)
 100                                         return video;
 101                         }
 102
 103                         packets_.pop();
 104                         file_frame_number_ = static_cast<uint32_t>(packet->pos);
 105                         avcodec_flush_buffers(codec_context_.get());
 106                         return flush_video();
 107                 }
 108
 109                 packets_.pop();
 110                 return decode(packet);
 111         }
 112
 113         std::shared_ptr<AVFrame> decode(spl::shared_ptr<AVPacket> pkt)
 114         {
 115                 auto decoded_frame = std::shared_ptr<AVFrame>(av_frame_alloc(), [](AVFrame* frame)
 116                 {
 117                         av_frame_free(&frame);
 118                 });
 119
 120                 int frame_finished = 0;
 121                 THROW_ON_ERROR2(avcodec_decode_video2(codec_context_.get(), decoded_frame.get(), &frame_finished, pkt.get()), "[video_decoder]");
 122
 123                 // If a decoder consumes less then the whole packet then something is wrong
 124                 // that might be just harmless padding at the end, or a problem with the
 125                 // AVParser or demuxer which puted more then one frame in a AVPacket.
 126
 127                 if(frame_finished == 0)
 128                         return nullptr;
 129
 130                 is_progressive_ = !decoded_frame->interlaced_frame;
 131
 132                 if(decoded_frame->repeat_pict > 0)
 133                         CASPAR_LOG(warning) << "[video_decoder] Field repeat_pict not implemented.";
 134
 135                 ++file_frame_number_;
 136
 137                 // This ties the life of the decoded_frame to the packet that it came from. For the
 138                 // current version of ffmpeg (0.8 or c17808c) the RAW_VIDEO codec returns frame data
 139                 // owned by the packet.
 140                 return std::shared_ptr<AVFrame>(decoded_frame.get(), [decoded_frame, pkt](AVFrame*){});
 141         }
 142
 143         bool ready() const
 144         {
 145                 return packets_.size() >= 8;
 146         }
 147
 148         uint32_t nb_frames() const
 149         {
 150                 return std::max(nb_frames_, static_cast<uint32_t>(file_frame_number_));
 151         }
 152
 153         std::wstring print() const
 154         {
 155                 return L"[video-decoder] " + u16(codec_context_->codec->long_name);
 156         }
 157 };
 158
 159 video_decoder::video_decoder(const spl::shared_ptr<AVFormatContext>& context) : impl_(new implementation(context)){}
 160 void video_decoder::push(const std::shared_ptr<AVPacket>& packet){impl_->push(packet);}
 161 std::shared_ptr<AVFrame> video_decoder::poll(){return impl_->poll();}
 162 bool video_decoder::ready() const{return impl_->ready();}
 163 int video_decoder::width() const{return impl_->width_;}
 164 int video_decoder::height() const{return impl_->height_;}
 165 uint32_t video_decoder::nb_frames() const{return impl_->nb_frames();}
 166 uint32_t video_decoder::file_frame_number() const{return static_cast<uint32_t>(impl_->file_frame_number_);}
 167 bool    video_decoder::is_progressive() const{return impl_->is_progressive_;}
 168 std::wstring video_decoder::print() const{return impl_->print();}
 169
 170 }}