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