git.sesse.net Git - nageru/blob - mixer.h

   1 #ifndef _MIXER_H
   2 #define _MIXER_H 1
   3
   4 // The actual video mixer, running in its own separate background thread.
   5
   6 #include <epoxy/gl.h>
   7 #undef Success
   8 #include <stdbool.h>
   9 #include <stdint.h>
  10
  11 #include <movit/effect_chain.h>
  12 #include <movit/flat_input.h>
  13 #include <zita-resampler/resampler.h>
  14 #include <atomic>
  15 #include <condition_variable>
  16 #include <cstddef>
  17 #include <functional>
  18 #include <memory>
  19 #include <mutex>
  20 #include <string>
  21 #include <thread>
  22 #include <vector>
  23
  24 #include "bmusb/bmusb.h"
  25 #include "ebu_r128_proc.h"
  26 #include "h264encode.h"
  27 #include "httpd.h"
  28 #include "pbo_frame_allocator.h"
  29 #include "ref_counted_frame.h"
  30 #include "ref_counted_gl_sync.h"
  31 #include "resampling_queue.h"
  32 #include "theme.h"
  33 #include "timebase.h"
  34 #include "stereocompressor.h"
  35 #include "filter.h"
  36
  37 class H264Encoder;
  38 class QSurface;
  39 namespace movit {
  40 class Effect;
  41 class EffectChain;
  42 class FlatInput;
  43 class ResourcePool;
  44 }  // namespace movit
  45
  46 namespace movit {
  47 class YCbCrInput;
  48 }
  49 class QOpenGLContext;
  50 class QSurfaceFormat;
  51
  52 class Mixer {
  53 public:
  54         // The surface format is used for offscreen destinations for OpenGL contexts we need.
  55         Mixer(const QSurfaceFormat &format, unsigned num_cards);
  56         ~Mixer();
  57         void start();
  58         void quit();
  59
  60         void transition_clicked(int transition_num);
  61         void channel_clicked(int preview_num);
  62
  63         enum Output {
  64                 OUTPUT_LIVE = 0,
  65                 OUTPUT_PREVIEW,
  66                 OUTPUT_INPUT0,  // 1, 2, 3, up to 15 follow numerically.
  67                 NUM_OUTPUTS = 18
  68         };
  69
  70         struct DisplayFrame {
  71                 // The chain for rendering this frame. To render a display frame,
  72                 // first wait for <ready_fence>, then call <setup_chain>
  73                 // to wire up all the inputs, and then finally call
  74                 // chain->render_to_screen() or similar.
  75                 movit::EffectChain *chain;
  76                 std::function<void()> setup_chain;
  77
  78                 // Asserted when all the inputs are ready; you cannot render the chain
  79                 // before this.
  80                 RefCountedGLsync ready_fence;
  81
  82                 // Holds on to all the input frames needed for this display frame,
  83                 // so they are not released while still rendering.
  84                 std::vector<RefCountedFrame> input_frames;
  85
  86                 // Textures that should be released back to the resource pool
  87                 // when this frame disappears, if any.
  88                 // TODO: Refcount these as well?
  89                 std::vector<GLuint> temp_textures;
  90         };
  91         // Implicitly frees the previous one if there's a new frame available.
  92         bool get_display_frame(Output output, DisplayFrame *frame) {
  93                 return output_channel[output].get_display_frame(frame);
  94         }
  95
  96         typedef std::function<void()> new_frame_ready_callback_t;
  97         void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
  98         {
  99                 output_channel[output].set_frame_ready_callback(callback);
 100         }
 101
 102         typedef std::function<void(float level_lufs, float peak_db,
 103                                    float global_level_lufs, float range_low_lufs, float range_high_lufs,
 104                                    float auto_gain_staging_db)> audio_level_callback_t;
 105         void set_audio_level_callback(audio_level_callback_t callback)
 106         {
 107                 audio_level_callback = callback;
 108         }
 109
 110         std::vector<std::string> get_transition_names()
 111         {
 112                 return theme->get_transition_names(pts());
 113         }
 114
 115         unsigned get_num_channels() const
 116         {
 117                 return theme->get_num_channels();
 118         }
 119
 120         std::string get_channel_name(unsigned channel) const
 121         {
 122                 return theme->get_channel_name(channel);
 123         }
 124
 125         bool get_supports_set_wb(unsigned channel) const
 126         {
 127                 return theme->get_supports_set_wb(channel);
 128         }
 129
 130         void set_wb(unsigned channel, double r, double g, double b) const
 131         {
 132                 theme->set_wb(channel, r, g, b);
 133         }
 134
 135         void set_locut_cutoff(float cutoff_hz)
 136         {
 137                 locut_cutoff_hz = cutoff_hz;
 138         }
 139
 140         void set_limiter_threshold_dbfs(float threshold_dbfs)
 141         {
 142                 limiter_threshold_dbfs = threshold_dbfs;
 143         }
 144
 145         void set_compressor_threshold_dbfs(float threshold_dbfs)
 146         {
 147                 compressor_threshold_dbfs = threshold_dbfs;
 148         }
 149
 150         void set_limiter_enabled(bool enabled)
 151         {
 152                 limiter_enabled = enabled;
 153         }
 154
 155         void set_compressor_enabled(bool enabled)
 156         {
 157                 compressor_enabled = enabled;
 158         }
 159
 160         void reset_meters();
 161
 162 private:
 163         void bm_frame(unsigned card_index, uint16_t timecode,
 164                 FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 165                 FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format);
 166         void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
 167         void thread_func();
 168         void process_audio_one_frame();
 169         void subsample_chroma(GLuint src_tex, GLuint dst_dst);
 170         void release_display_frame(DisplayFrame *frame);
 171         double pts() { return double(pts_int) / TIMEBASE; }
 172
 173         HTTPD httpd;
 174         unsigned num_cards;
 175
 176         QSurface *mixer_surface, *h264_encoder_surface;
 177         std::unique_ptr<movit::ResourcePool> resource_pool;
 178         std::unique_ptr<Theme> theme;
 179         std::unique_ptr<movit::EffectChain> display_chain;
 180         GLuint cbcr_program_num;  // Owned by <resource_pool>.
 181         std::unique_ptr<H264Encoder> h264_encoder;
 182
 183         // Effects part of <display_chain>. Owned by <display_chain>.
 184         movit::FlatInput *display_input;
 185
 186         int64_t pts_int = 0;  // In TIMEBASE units.
 187
 188         std::mutex bmusb_mutex;
 189         struct CaptureCard {
 190                 BMUSBCapture *usb;
 191                 std::unique_ptr<PBOFrameAllocator> frame_allocator;
 192
 193                 // Stuff for the OpenGL context (for texture uploading).
 194                 QSurface *surface;
 195                 QOpenGLContext *context;
 196
 197                 bool new_data_ready = false;  // Whether new_frame contains anything.
 198                 bool should_quit = false;
 199                 RefCountedFrame new_frame;
 200                 GLsync new_data_ready_fence;  // Whether new_frame is ready for rendering.
 201                 std::condition_variable new_data_ready_changed;  // Set whenever new_data_ready is changed.
 202                 unsigned dropped_frames = 0;  // Before new_frame.
 203
 204                 std::mutex audio_mutex;
 205                 std::unique_ptr<ResamplingQueue> resampling_queue;  // Under audio_mutex.
 206                 int last_timecode = -1;  // Unwrapped.
 207         };
 208         CaptureCard cards[MAX_CARDS];  // protected by <bmusb_mutex>
 209
 210         RefCountedFrame bmusb_current_rendering_frame[MAX_CARDS];
 211
 212         class OutputChannel {
 213         public:
 214                 ~OutputChannel();
 215                 void output_frame(DisplayFrame frame);
 216                 bool get_display_frame(DisplayFrame *frame);
 217                 void set_frame_ready_callback(new_frame_ready_callback_t callback);
 218
 219         private:
 220                 friend class Mixer;
 221
 222                 Mixer *parent = nullptr;  // Not owned.
 223                 std::mutex frame_mutex;
 224                 DisplayFrame current_frame, ready_frame;  // protected by <frame_mutex>
 225                 bool has_current_frame = false, has_ready_frame = false;  // protected by <frame_mutex>
 226                 new_frame_ready_callback_t new_frame_ready_callback;
 227                 bool has_new_frame_ready_callback = false;
 228         };
 229         OutputChannel output_channel[NUM_OUTPUTS];
 230
 231         std::thread mixer_thread;
 232         bool should_quit = false;
 233
 234         audio_level_callback_t audio_level_callback = nullptr;
 235         Ebu_r128_proc r128;
 236
 237         Resampler peak_resampler;
 238         std::atomic<float> peak{0.0f};
 239
 240         StereoFilter locut;  // Default cutoff 150 Hz, 24 dB/oct.
 241         std::atomic<float> locut_cutoff_hz;
 242
 243         // First compressor; takes us up to about -12 dBFS.
 244         StereoCompressor level_compressor;
 245         float last_gain_staging_db = 0.0f;
 246
 247         static constexpr float ref_level_dbfs = -14.0f;
 248
 249         StereoCompressor limiter;
 250         std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 0.0f};   // 0 dB.
 251         std::atomic<bool> limiter_enabled{true};
 252         StereoCompressor compressor;
 253         std::atomic<float> compressor_threshold_dbfs{ref_level_dbfs - 12.0f};  // -12 dB.
 254         std::atomic<bool> compressor_enabled{true};
 255 };
 256
 257 extern Mixer *global_mixer;
 258
 259 #endif  // !defined(_MIXER_H)