git.sesse.net Git - nageru/blob - futatabi/video_stream.h

   1 #ifndef _VIDEO_STREAM_H
   2 #define _VIDEO_STREAM_H 1
   3
   4 #include <epoxy/gl.h>
   5 #include <stdint.h>
   6
   7 extern "C" {
   8 #include <libavformat/avformat.h>
   9 #include <libavformat/avio.h>
  10 }
  11
  12 #include "frame_on_disk.h"
  13 #include "jpeg_frame_view.h"
  14 #include "queue_spot_holder.h"
  15 #include "shared/mux.h"
  16 #include "shared/ref_counted_gl_sync.h"
  17
  18 #include <atomic>
  19 #include <chrono>
  20 #include <condition_variable>
  21 #include <deque>
  22 #include <functional>
  23 #include <movit/effect_chain.h>
  24 #include <movit/mix_effect.h>
  25 #include <movit/ycbcr_input.h>
  26 #include <mutex>
  27 #include <string>
  28 #include <thread>
  29
  30 class ChromaSubsampler;
  31 class DISComputeFlow;
  32 class Interpolate;
  33 class QSurface;
  34 class QSurfaceFormat;
  35 class YCbCrConverter;
  36
  37 class VideoStream {
  38 public:
  39         VideoStream(AVFormatContext *file_avctx);  // nullptr if output to stream.
  40         ~VideoStream();
  41         void start();
  42         void stop();
  43         void clear_queue();
  44
  45         // “display_func” is called after the frame has been calculated (if needed)
  46         // and has gone out to the stream.
  47         void schedule_original_frame(std::chrono::steady_clock::time_point,
  48                                      int64_t output_pts, std::function<void()> &&display_func,
  49                                      QueueSpotHolder &&queue_spot_holder,
  50                                      FrameOnDisk frame, const std::string &subtitle,
  51                                      bool include_audio);
  52         void schedule_faded_frame(std::chrono::steady_clock::time_point, int64_t output_pts,
  53                                   std::function<void()> &&display_func,
  54                                   QueueSpotHolder &&queue_spot_holder,
  55                                   FrameOnDisk frame1, FrameOnDisk frame2,
  56                                   float fade_alpha, const std::string &subtitle);  // Always no audio.
  57         void schedule_interpolated_frame(std::chrono::steady_clock::time_point, int64_t output_pts,
  58                                          std::function<void(std::shared_ptr<Frame>)> &&display_func,
  59                                          QueueSpotHolder &&queue_spot_holder,
  60                                          FrameOnDisk frame1, FrameOnDisk frame2,
  61                                          float alpha, FrameOnDisk secondary_frame,  // Empty = no secondary (fade) frame.
  62                                          float fade_alpha, const std::string &subtitle,
  63                                          bool include_audio);
  64         void schedule_refresh_frame(std::chrono::steady_clock::time_point, int64_t output_pts,
  65                                     std::function<void()> &&display_func,
  66                                     QueueSpotHolder &&queue_spot_holder, const std::string &subtitle);  // Always no audio.
  67         void schedule_silence(std::chrono::steady_clock::time_point, int64_t output_pts,
  68                               int64_t length_pts, QueueSpotHolder &&queue_spot_holder);
  69
  70 private:
  71         struct QueuedFrame;
  72
  73         FrameReader frame_reader;
  74
  75         void encode_thread_func();
  76         std::thread encode_thread;
  77         std::atomic<bool> should_quit{ false };
  78
  79         static int write_packet2_thunk(void *opaque, uint8_t *buf, int buf_size, AVIODataMarkerType type, int64_t time);
  80         int write_packet2(uint8_t *buf, int buf_size, AVIODataMarkerType type, int64_t time);
  81         void add_silence(int64_t pts, int64_t length_pts);
  82         void add_audio_or_silence(const QueuedFrame &qf);
  83
  84         // Allocated at the very start; if we're empty, we start dropping frames
  85         // (so that we don't build up an infinite interpolation backlog).
  86         struct InterpolatedFrameResources {
  87                 VideoStream *owner;  // Used only for IFRReleaser, below.
  88
  89                 GLuint input_tex;  // Layered (contains both input frames), Y'CbCr.
  90                 GLuint gray_tex;  // Same, but Y only.
  91                 GLuint input_fbos[2];  // For rendering to the two layers of input_tex.
  92
  93                 // Destination textures and FBO if there is a fade.
  94                 GLuint fade_y_output_tex, fade_cbcr_output_tex;
  95                 GLuint fade_fbo;
  96
  97                 GLuint cb_tex, cr_tex;  // Subsampled, final output.
  98
  99                 GLuint pbo;  // For reading the data back.
 100                 void *pbo_contents;  // Persistently mapped.
 101         };
 102         std::mutex queue_lock;
 103         std::deque<std::unique_ptr<InterpolatedFrameResources>> interpolate_resources;  // Under <queue_lock>.
 104         static constexpr size_t num_interpolate_slots = 15;  // Should be larger than Player::max_queued_frames, or we risk mass-dropping frames.
 105
 106         struct IFRReleaser {
 107                 void operator()(InterpolatedFrameResources *ifr) const
 108                 {
 109                         if (ifr != nullptr) {
 110                                 std::lock_guard<std::mutex> lock(ifr->owner->queue_lock);
 111                                 ifr->owner->interpolate_resources.emplace_back(ifr);
 112                         }
 113                 }
 114         };
 115         using BorrowedInterpolatedFrameResources = std::unique_ptr<InterpolatedFrameResources, IFRReleaser>;
 116
 117         struct QueuedFrame {
 118                 std::chrono::steady_clock::time_point local_pts;
 119
 120                 int64_t output_pts;
 121                 enum Type { ORIGINAL, FADED, INTERPOLATED, FADED_INTERPOLATED, REFRESH, SILENCE } type;
 122
 123                 // For original frames only. Made move-only so we know explicitly
 124                 // we don't copy these ~200 kB files around inadvertedly.
 125                 std::unique_ptr<std::string> encoded_jpeg;
 126
 127                 // For everything except original frames and silence.
 128                 FrameOnDisk frame1;
 129
 130                 // For fades only (including fades against interpolated frames).
 131                 FrameOnDisk secondary_frame;
 132
 133                 // For interpolated frames only.
 134                 FrameOnDisk frame2;
 135                 float alpha;
 136                 BorrowedInterpolatedFrameResources resources;
 137                 RefCountedGLsync fence;  // Set when the interpolated image is read back to the CPU.
 138                 std::chrono::steady_clock::time_point fence_created;
 139                 GLuint flow_tex, output_tex, cbcr_tex;  // Released in the receiving thread; not really used for anything else. flow_tex will typically even be from a previous frame.
 140                 FrameOnDisk id;
 141
 142                 std::function<void()> display_func;  // Called when the image is done decoding.
 143                 std::function<void(std::shared_ptr<Frame>)> display_decoded_func;  // Same, except for INTERPOLATED and FADED_INTERPOLATED.
 144
 145                 std::string subtitle;  // Blank for none.
 146                 std::string exif_data;  // Blank for none.
 147
 148                 // Audio, in stereo interleaved 32-bit PCM. If empty and not of type SILENCE, one frame's worth of silence samples
 149                 // is synthesized.
 150                 std::string audio;
 151
 152                 // For silence frames only.
 153                 int64_t silence_length_pts;
 154
 155                 QueueSpotHolder queue_spot_holder;
 156         };
 157         std::deque<QueuedFrame> frame_queue;  // Under <queue_lock>.
 158         std::condition_variable queue_changed;
 159
 160         AVFormatContext *avctx;
 161         std::unique_ptr<Mux> mux;  // To HTTP, or to file.
 162         std::string stream_mux_header;  // Only used in HTTP.
 163         bool seen_sync_markers = false;
 164         bool output_fast_forward;
 165
 166         std::unique_ptr<YCbCrConverter> ycbcr_converter;
 167         std::unique_ptr<YCbCrConverter> ycbcr_semiplanar_converter;
 168
 169         // Frame interpolation.
 170         std::unique_ptr<DISComputeFlow> compute_flow;
 171         std::unique_ptr<Interpolate> interpolate, interpolate_no_split;
 172         std::unique_ptr<ChromaSubsampler> chroma_subsampler;
 173
 174         // Cached flow computation from previous frame, if any.
 175         GLuint last_flow_tex = 0;
 176         FrameOnDisk last_frame1, last_frame2;
 177
 178         std::string last_frame;
 179         Mux::WithSubtitles with_subtitles;  // true for streaming, false for export to file.
 180 };
 181
 182 #endif  // !defined(_VIDEO_STREAM_H)