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 "alsa_output.h"
  26 #include "ebu_r128_proc.h"
  27 #include "h264encode.h"
  28 #include "httpd.h"
  29 #include "pbo_frame_allocator.h"
  30 #include "ref_counted_frame.h"
  31 #include "ref_counted_gl_sync.h"
  32 #include "resampling_queue.h"
  33 #include "theme.h"
  34 #include "timebase.h"
  35 #include "stereocompressor.h"
  36 #include "filter.h"
  37 #include "input_state.h"
  38
  39 class H264Encoder;
  40 class QSurface;
  41 namespace movit {
  42 class Effect;
  43 class EffectChain;
  44 class FlatInput;
  45 class ResourcePool;
  46 }  // namespace movit
  47
  48 namespace movit {
  49 class YCbCrInput;
  50 }
  51 class QOpenGLContext;
  52 class QSurfaceFormat;
  53
  54 class Mixer {
  55 public:
  56         // The surface format is used for offscreen destinations for OpenGL contexts we need.
  57         Mixer(const QSurfaceFormat &format, unsigned num_cards);
  58         ~Mixer();
  59         void start();
  60         void quit();
  61
  62         void transition_clicked(int transition_num);
  63         void channel_clicked(int preview_num);
  64
  65         enum Output {
  66                 OUTPUT_LIVE = 0,
  67                 OUTPUT_PREVIEW,
  68                 OUTPUT_INPUT0,  // 1, 2, 3, up to 15 follow numerically.
  69                 NUM_OUTPUTS = 18
  70         };
  71
  72         struct DisplayFrame {
  73                 // The chain for rendering this frame. To render a display frame,
  74                 // first wait for <ready_fence>, then call <setup_chain>
  75                 // to wire up all the inputs, and then finally call
  76                 // chain->render_to_screen() or similar.
  77                 movit::EffectChain *chain;
  78                 std::function<void()> setup_chain;
  79
  80                 // Asserted when all the inputs are ready; you cannot render the chain
  81                 // before this.
  82                 RefCountedGLsync ready_fence;
  83
  84                 // Holds on to all the input frames needed for this display frame,
  85                 // so they are not released while still rendering.
  86                 std::vector<RefCountedFrame> input_frames;
  87
  88                 // Textures that should be released back to the resource pool
  89                 // when this frame disappears, if any.
  90                 // TODO: Refcount these as well?
  91                 std::vector<GLuint> temp_textures;
  92         };
  93         // Implicitly frees the previous one if there's a new frame available.
  94         bool get_display_frame(Output output, DisplayFrame *frame) {
  95                 return output_channel[output].get_display_frame(frame);
  96         }
  97
  98         typedef std::function<void()> new_frame_ready_callback_t;
  99         void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
 100         {
 101                 output_channel[output].set_frame_ready_callback(callback);
 102         }
 103
 104         typedef std::function<void(float level_lufs, float peak_db,
 105                                    float global_level_lufs, float range_low_lufs, float range_high_lufs,
 106                                    float auto_gain_staging_db)> audio_level_callback_t;
 107         void set_audio_level_callback(audio_level_callback_t callback)
 108         {
 109                 audio_level_callback = callback;
 110         }
 111
 112         std::vector<std::string> get_transition_names()
 113         {
 114                 return theme->get_transition_names(pts());
 115         }
 116
 117         unsigned get_num_channels() const
 118         {
 119                 return theme->get_num_channels();
 120         }
 121
 122         std::string get_channel_name(unsigned channel) const
 123         {
 124                 return theme->get_channel_name(channel);
 125         }
 126
 127         bool get_supports_set_wb(unsigned channel) const
 128         {
 129                 return theme->get_supports_set_wb(channel);
 130         }
 131
 132         void set_wb(unsigned channel, double r, double g, double b) const
 133         {
 134                 theme->set_wb(channel, r, g, b);
 135         }
 136
 137         void set_locut_cutoff(float cutoff_hz)
 138         {
 139                 locut_cutoff_hz = cutoff_hz;
 140         }
 141
 142         float get_limiter_threshold_dbfs()
 143         {
 144                 return limiter_threshold_dbfs;
 145         }
 146
 147         float get_compressor_threshold_dbfs()
 148         {
 149                 return compressor_threshold_dbfs;
 150         }
 151
 152         void set_limiter_threshold_dbfs(float threshold_dbfs)
 153         {
 154                 limiter_threshold_dbfs = threshold_dbfs;
 155         }
 156
 157         void set_compressor_threshold_dbfs(float threshold_dbfs)
 158         {
 159                 compressor_threshold_dbfs = threshold_dbfs;
 160         }
 161
 162         void set_limiter_enabled(bool enabled)
 163         {
 164                 limiter_enabled = enabled;
 165         }
 166
 167         void set_compressor_enabled(bool enabled)
 168         {
 169                 compressor_enabled = enabled;
 170         }
 171
 172         void reset_meters();
 173
 174 private:
 175         void bm_frame(unsigned card_index, uint16_t timecode,
 176                 FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
 177                 FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format);
 178         void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
 179         void thread_func();
 180         void audio_thread_func();
 181         void process_audio_one_frame(int64_t frame_pts_int, int num_samples);
 182         void subsample_chroma(GLuint src_tex, GLuint dst_dst);
 183         void release_display_frame(DisplayFrame *frame);
 184         double pts() { return double(pts_int) / TIMEBASE; }
 185
 186         HTTPD httpd;
 187         unsigned num_cards;
 188
 189         QSurface *mixer_surface, *h264_encoder_surface;
 190         std::unique_ptr<movit::ResourcePool> resource_pool;
 191         std::unique_ptr<Theme> theme;
 192         std::unique_ptr<movit::EffectChain> display_chain;
 193         GLuint cbcr_program_num;  // Owned by <resource_pool>.
 194         std::unique_ptr<H264Encoder> h264_encoder;
 195
 196         // Effects part of <display_chain>. Owned by <display_chain>.
 197         movit::FlatInput *display_input;
 198
 199         int64_t pts_int = 0;  // In TIMEBASE units.
 200
 201         std::mutex bmusb_mutex;
 202         struct CaptureCard {
 203                 BMUSBCapture *usb;
 204                 std::unique_ptr<PBOFrameAllocator> frame_allocator;
 205
 206                 // Stuff for the OpenGL context (for texture uploading).
 207                 QSurface *surface;
 208                 QOpenGLContext *context;
 209
 210                 bool new_data_ready = false;  // Whether new_frame contains anything.
 211                 bool should_quit = false;
 212                 RefCountedFrame new_frame;
 213                 int64_t new_frame_length;  // In TIMEBASE units.
 214                 bool new_frame_interlaced;
 215                 unsigned new_frame_field;  // Which field (0 or 1) of the frame to use. Always 0 for progressive.
 216                 GLsync new_data_ready_fence;  // Whether new_frame is ready for rendering.
 217                 std::condition_variable new_data_ready_changed;  // Set whenever new_data_ready is changed.
 218                 unsigned dropped_frames = 0;  // Before new_frame.
 219
 220                 // Accumulated errors in number of 1/TIMEBASE samples. If OUTPUT_FREQUENCY divided by
 221                 // frame rate is integer, will always stay zero.
 222                 unsigned fractional_samples = 0;
 223
 224                 std::mutex audio_mutex;
 225                 std::unique_ptr<ResamplingQueue> resampling_queue;  // Under audio_mutex.
 226                 int last_timecode = -1;  // Unwrapped.
 227                 int64_t next_local_pts = 0;  // Beginning of next frame, in TIMEBASE units.
 228         };
 229         CaptureCard cards[MAX_CARDS];  // protected by <bmusb_mutex>
 230
 231         InputState input_state;
 232
 233         class OutputChannel {
 234         public:
 235                 ~OutputChannel();
 236                 void output_frame(DisplayFrame frame);
 237                 bool get_display_frame(DisplayFrame *frame);
 238                 void set_frame_ready_callback(new_frame_ready_callback_t callback);
 239
 240         private:
 241                 friend class Mixer;
 242
 243                 Mixer *parent = nullptr;  // Not owned.
 244                 std::mutex frame_mutex;
 245                 DisplayFrame current_frame, ready_frame;  // protected by <frame_mutex>
 246                 bool has_current_frame = false, has_ready_frame = false;  // protected by <frame_mutex>
 247                 new_frame_ready_callback_t new_frame_ready_callback;
 248                 bool has_new_frame_ready_callback = false;
 249         };
 250         OutputChannel output_channel[NUM_OUTPUTS];
 251
 252         std::thread mixer_thread;
 253         std::thread audio_thread;
 254         std::atomic<bool> should_quit{false};
 255
 256         audio_level_callback_t audio_level_callback = nullptr;
 257         std::mutex r128_mutex;
 258         Ebu_r128_proc r128;  // Under r128_mutex.
 259
 260         Resampler peak_resampler;
 261         std::atomic<float> peak{0.0f};
 262
 263         StereoFilter locut;  // Default cutoff 150 Hz, 24 dB/oct.
 264         std::atomic<float> locut_cutoff_hz;
 265
 266         // First compressor; takes us up to about -12 dBFS.
 267         StereoCompressor level_compressor;
 268         float last_gain_staging_db = 0.0f;
 269
 270         static constexpr float ref_level_dbfs = -14.0f;
 271
 272         StereoCompressor limiter;
 273         std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f};   // 4 dB.
 274         std::atomic<bool> limiter_enabled{true};
 275         StereoCompressor compressor;
 276         std::atomic<float> compressor_threshold_dbfs{ref_level_dbfs - 12.0f};  // -12 dB.
 277         std::atomic<bool> compressor_enabled{true};
 278
 279         std::unique_ptr<ALSAOutput> alsa;
 280
 281         struct AudioTask {
 282                 int64_t pts_int;
 283                 int num_samples;
 284         };
 285         std::mutex audio_mutex;
 286         std::condition_variable audio_task_queue_changed;
 287         std::queue<AudioTask> audio_task_queue;  // Under audio_mutex.
 288 };
 289
 290 extern Mixer *global_mixer;
 291
 292 #endif  // !defined(_MIXER_H)