4 // The actual video mixer, running in its own separate background thread.
11 #include <movit/effect_chain.h>
12 #include <movit/flat_input.h>
13 #include <zita-resampler/resampler.h>
15 #include <condition_variable>
24 #include "bmusb/bmusb.h"
25 #include "alsa_output.h"
26 #include "ebu_r128_proc.h"
27 #include "video_encoder.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"
35 #include "stereocompressor.h"
37 #include "input_state.h"
38 #include "correlation_measurer.h"
40 class QuickSyncEncoder;
54 // For any card that's not the master (where we pick out the frames as they
55 // come, as fast as we can process), there's going to be a queue. The question
56 // is when we should drop frames from that queue (apart from the obvious
57 // dropping if the 16-frame queue should become full), especially given that
58 // the frame rate could be lower or higher than the master (either subtly or
59 // dramatically). We have two (conflicting) demands:
61 // 1. We want to avoid starving the queue.
62 // 2. We don't want to add more delay than is needed.
64 // Our general strategy is to drop as many frames as we can (helping for #2)
65 // that we think is safe for #1 given jitter. To this end, we set a lower floor N,
66 // where we assume that if we have N frames in the queue, we're always safe from
67 // starvation. (Typically, N will be 0 or 1. It starts off at 0.) If we have
68 // more than N frames in the queue after reading out the one we need, we head-drop
69 // them to reduce the queue.
71 // N is reduced as follows: If the queue has had at least one spare frame for
72 // at least 50 (master) frames (ie., it's been too conservative for a second),
73 // we reduce N by 1 and reset the timers. TODO: Only do this if N ever actually
76 // Whenever the queue is starved (we needed a frame but there was none),
77 // and we've been at N since the last starvation, N was obviously too low,
78 // so we increment it. We will never set N above 5, though.
79 class QueueLengthPolicy {
81 QueueLengthPolicy() {}
82 void reset(unsigned card_index) {
83 this->card_index = card_index;
84 safe_queue_length = 0;
85 frames_with_at_least_one = 0;
86 been_at_safe_point_since_last_starvation = false;
89 void update_policy(int queue_length); // Give in -1 for starvation.
90 unsigned get_safe_queue_length() const { return safe_queue_length; }
93 unsigned card_index; // For debugging only.
94 unsigned safe_queue_length = 0; // Called N in the comments.
95 unsigned frames_with_at_least_one = 0;
96 bool been_at_safe_point_since_last_starvation = false;
101 // The surface format is used for offscreen destinations for OpenGL contexts we need.
102 Mixer(const QSurfaceFormat &format, unsigned num_cards);
107 void transition_clicked(int transition_num);
108 void channel_clicked(int preview_num);
113 OUTPUT_INPUT0, // 1, 2, 3, up to 15 follow numerically.
117 struct DisplayFrame {
118 // The chain for rendering this frame. To render a display frame,
119 // first wait for <ready_fence>, then call <setup_chain>
120 // to wire up all the inputs, and then finally call
121 // chain->render_to_screen() or similar.
122 movit::EffectChain *chain;
123 std::function<void()> setup_chain;
125 // Asserted when all the inputs are ready; you cannot render the chain
127 RefCountedGLsync ready_fence;
129 // Holds on to all the input frames needed for this display frame,
130 // so they are not released while still rendering.
131 std::vector<RefCountedFrame> input_frames;
133 // Textures that should be released back to the resource pool
134 // when this frame disappears, if any.
135 // TODO: Refcount these as well?
136 std::vector<GLuint> temp_textures;
138 // Implicitly frees the previous one if there's a new frame available.
139 bool get_display_frame(Output output, DisplayFrame *frame) {
140 return output_channel[output].get_display_frame(frame);
143 typedef std::function<void()> new_frame_ready_callback_t;
144 void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
146 output_channel[output].set_frame_ready_callback(callback);
149 // TODO: Should this really be per-channel? Shouldn't it just be called for e.g. the live output?
150 typedef std::function<void(const std::vector<std::string> &)> transition_names_updated_callback_t;
151 void set_transition_names_updated_callback(Output output, transition_names_updated_callback_t callback)
153 output_channel[output].set_transition_names_updated_callback(callback);
156 typedef std::function<void(const std::string &)> name_updated_callback_t;
157 void set_name_updated_callback(Output output, name_updated_callback_t callback)
159 output_channel[output].set_name_updated_callback(callback);
162 typedef std::function<void(const std::string &)> color_updated_callback_t;
163 void set_color_updated_callback(Output output, color_updated_callback_t callback)
165 output_channel[output].set_color_updated_callback(callback);
168 typedef std::function<void(float level_lufs, float peak_db,
169 float global_level_lufs, float range_low_lufs, float range_high_lufs,
170 float gain_staging_db, float final_makeup_gain_db,
171 float correlation)> audio_level_callback_t;
172 void set_audio_level_callback(audio_level_callback_t callback)
174 audio_level_callback = callback;
177 std::vector<std::string> get_transition_names()
179 return theme->get_transition_names(pts());
182 unsigned get_num_channels() const
184 return theme->get_num_channels();
187 std::string get_channel_name(unsigned channel) const
189 return theme->get_channel_name(channel);
192 std::string get_channel_color(unsigned channel) const
194 return theme->get_channel_color(channel);
197 int get_channel_signal(unsigned channel) const
199 return theme->get_channel_signal(channel);
202 int map_signal(unsigned channel)
204 return theme->map_signal(channel);
207 unsigned get_audio_source() const
209 return audio_source_channel;
212 void set_audio_source(unsigned channel)
214 audio_source_channel = channel;
217 unsigned get_master_clock() const
219 return master_clock_channel;
222 void set_master_clock(unsigned channel)
224 master_clock_channel = channel;
227 void set_signal_mapping(int signal, int card)
229 return theme->set_signal_mapping(signal, card);
232 bool get_supports_set_wb(unsigned channel) const
234 return theme->get_supports_set_wb(channel);
237 void set_wb(unsigned channel, double r, double g, double b) const
239 theme->set_wb(channel, r, g, b);
242 void set_locut_cutoff(float cutoff_hz)
244 locut_cutoff_hz = cutoff_hz;
247 void set_locut_enabled(bool enabled)
249 locut_enabled = enabled;
252 bool get_locut_enabled() const
254 return locut_enabled;
257 float get_limiter_threshold_dbfs()
259 return limiter_threshold_dbfs;
262 float get_compressor_threshold_dbfs()
264 return compressor_threshold_dbfs;
267 void set_limiter_threshold_dbfs(float threshold_dbfs)
269 limiter_threshold_dbfs = threshold_dbfs;
272 void set_compressor_threshold_dbfs(float threshold_dbfs)
274 compressor_threshold_dbfs = threshold_dbfs;
277 void set_limiter_enabled(bool enabled)
279 limiter_enabled = enabled;
282 bool get_limiter_enabled() const
284 return limiter_enabled;
287 void set_compressor_enabled(bool enabled)
289 compressor_enabled = enabled;
292 bool get_compressor_enabled() const
294 return compressor_enabled;
297 void set_gain_staging_db(float gain_db)
299 std::unique_lock<std::mutex> lock(compressor_mutex);
300 level_compressor_enabled = false;
301 gain_staging_db = gain_db;
304 void set_gain_staging_auto(bool enabled)
306 std::unique_lock<std::mutex> lock(compressor_mutex);
307 level_compressor_enabled = enabled;
310 bool get_gain_staging_auto() const
312 std::unique_lock<std::mutex> lock(compressor_mutex);
313 return level_compressor_enabled;
316 void set_final_makeup_gain_db(float gain_db)
318 std::unique_lock<std::mutex> lock(compressor_mutex);
319 final_makeup_gain_auto = false;
320 final_makeup_gain = pow(10.0f, gain_db / 20.0f);
323 void set_final_makeup_gain_auto(bool enabled)
325 std::unique_lock<std::mutex> lock(compressor_mutex);
326 final_makeup_gain_auto = enabled;
336 unsigned get_num_cards() const { return num_cards; }
338 std::string get_card_description(unsigned card_index) const {
339 assert(card_index < num_cards);
340 return cards[card_index].capture->get_description();
343 std::map<uint32_t, VideoMode> get_available_video_modes(unsigned card_index) const {
344 assert(card_index < num_cards);
345 return cards[card_index].capture->get_available_video_modes();
348 uint32_t get_current_video_mode(unsigned card_index) const {
349 assert(card_index < num_cards);
350 return cards[card_index].capture->get_current_video_mode();
353 void set_video_mode(unsigned card_index, uint32_t mode) {
354 assert(card_index < num_cards);
355 cards[card_index].capture->set_video_mode(mode);
358 void start_mode_scanning(unsigned card_index);
360 std::map<uint32_t, std::string> get_available_video_inputs(unsigned card_index) const {
361 assert(card_index < num_cards);
362 return cards[card_index].capture->get_available_video_inputs();
365 uint32_t get_current_video_input(unsigned card_index) const {
366 assert(card_index < num_cards);
367 return cards[card_index].capture->get_current_video_input();
370 void set_video_input(unsigned card_index, uint32_t input) {
371 assert(card_index < num_cards);
372 cards[card_index].capture->set_video_input(input);
375 std::map<uint32_t, std::string> get_available_audio_inputs(unsigned card_index) const {
376 assert(card_index < num_cards);
377 return cards[card_index].capture->get_available_audio_inputs();
380 uint32_t get_current_audio_input(unsigned card_index) const {
381 assert(card_index < num_cards);
382 return cards[card_index].capture->get_current_audio_input();
385 void set_audio_input(unsigned card_index, uint32_t input) {
386 assert(card_index < num_cards);
387 cards[card_index].capture->set_audio_input(input);
390 void change_x264_bitrate(unsigned rate_kbit) {
391 video_encoder->change_x264_bitrate(rate_kbit);
395 void configure_card(unsigned card_index, CaptureInterface *capture, bool is_fake_capture);
396 void bm_frame(unsigned card_index, uint16_t timecode,
397 FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
398 FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format);
399 void bm_hotplug_add(libusb_device *dev);
400 void bm_hotplug_remove(unsigned card_index);
401 void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
403 void handle_hotplugged_cards();
404 void schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame);
405 void render_one_frame(int64_t duration);
406 void send_audio_level_callback();
407 void audio_thread_func();
408 void process_audio_one_frame(int64_t frame_pts_int, int num_samples);
409 void subsample_chroma(GLuint src_tex, GLuint dst_dst);
410 void release_display_frame(DisplayFrame *frame);
411 double pts() { return double(pts_int) / TIMEBASE; }
416 QSurface *mixer_surface, *h264_encoder_surface;
417 std::unique_ptr<movit::ResourcePool> resource_pool;
418 std::unique_ptr<Theme> theme;
419 std::atomic<unsigned> audio_source_channel{0};
420 std::atomic<unsigned> master_clock_channel{0};
421 std::unique_ptr<movit::EffectChain> display_chain;
422 GLuint cbcr_program_num; // Owned by <resource_pool>.
423 GLuint cbcr_vbo; // Holds position and texcoord data.
424 GLuint cbcr_position_attribute_index, cbcr_texcoord_attribute_index;
425 std::unique_ptr<VideoEncoder> video_encoder;
427 // Effects part of <display_chain>. Owned by <display_chain>.
428 movit::FlatInput *display_input;
430 int64_t pts_int = 0; // In TIMEBASE units.
432 std::mutex bmusb_mutex;
433 bool has_bmusb_thread = false;
435 CaptureInterface *capture = nullptr;
436 bool is_fake_capture;
437 std::unique_ptr<PBOFrameAllocator> frame_allocator;
439 // Stuff for the OpenGL context (for texture uploading).
440 QSurface *surface = nullptr;
443 RefCountedFrame frame;
444 int64_t length; // In TIMEBASE units.
446 unsigned field; // Which field (0 or 1) of the frame to use. Always 0 for progressive.
447 std::function<void()> upload_func; // Needs to be called to actually upload the texture to OpenGL.
448 unsigned dropped_frames = 0; // Number of dropped frames before this one.
450 std::queue<NewFrame> new_frames;
451 bool should_quit = false;
452 std::condition_variable new_frames_changed; // Set whenever new_frames (or should_quit) is changed.
454 QueueLengthPolicy queue_length_policy; // Refers to the "new_frames" queue.
456 // Accumulated errors in number of 1/TIMEBASE samples. If OUTPUT_FREQUENCY divided by
457 // frame rate is integer, will always stay zero.
458 unsigned fractional_samples = 0;
460 std::mutex audio_mutex;
461 std::unique_ptr<ResamplingQueue> resampling_queue; // Under audio_mutex.
462 int last_timecode = -1; // Unwrapped.
463 int64_t next_local_pts = 0; // Beginning of next frame, in TIMEBASE units.
465 CaptureCard cards[MAX_CARDS]; // protected by <bmusb_mutex>
466 void get_one_frame_from_each_card(unsigned master_card_index, CaptureCard::NewFrame new_frames[MAX_CARDS], bool has_new_frame[MAX_CARDS], int num_samples[MAX_CARDS]);
468 InputState input_state;
470 // Cards we have been noticed about being hotplugged, but haven't tried adding yet.
471 // Protected by its own mutex.
472 std::mutex hotplug_mutex;
473 std::vector<libusb_device *> hotplugged_cards;
475 class OutputChannel {
478 void output_frame(DisplayFrame frame);
479 bool get_display_frame(DisplayFrame *frame);
480 void set_frame_ready_callback(new_frame_ready_callback_t callback);
481 void set_transition_names_updated_callback(transition_names_updated_callback_t callback);
482 void set_name_updated_callback(name_updated_callback_t callback);
483 void set_color_updated_callback(color_updated_callback_t callback);
489 Mixer *parent = nullptr; // Not owned.
490 std::mutex frame_mutex;
491 DisplayFrame current_frame, ready_frame; // protected by <frame_mutex>
492 bool has_current_frame = false, has_ready_frame = false; // protected by <frame_mutex>
493 new_frame_ready_callback_t new_frame_ready_callback;
494 transition_names_updated_callback_t transition_names_updated_callback;
495 name_updated_callback_t name_updated_callback;
496 color_updated_callback_t color_updated_callback;
498 std::vector<std::string> last_transition_names;
499 std::string last_name, last_color;
501 OutputChannel output_channel[NUM_OUTPUTS];
503 std::thread mixer_thread;
504 std::thread audio_thread;
505 std::atomic<bool> should_quit{false};
506 std::atomic<bool> should_cut{false};
508 audio_level_callback_t audio_level_callback = nullptr;
509 mutable std::mutex compressor_mutex;
510 Ebu_r128_proc r128; // Under compressor_mutex.
511 CorrelationMeasurer correlation; // Under compressor_mutex.
513 Resampler peak_resampler;
514 std::atomic<float> peak{0.0f};
516 StereoFilter locut; // Default cutoff 120 Hz, 24 dB/oct.
517 std::atomic<float> locut_cutoff_hz;
518 std::atomic<bool> locut_enabled{true};
520 // First compressor; takes us up to about -12 dBFS.
521 StereoCompressor level_compressor; // Under compressor_mutex. Used to set/override gain_staging_db if <level_compressor_enabled>.
522 float gain_staging_db = 0.0f; // Under compressor_mutex.
523 bool level_compressor_enabled = true; // Under compressor_mutex.
525 static constexpr float ref_level_dbfs = -14.0f; // Chosen so that we end up around 0 LU in practice.
526 static constexpr float ref_level_lufs = -23.0f; // 0 LU, more or less by definition.
528 StereoCompressor limiter;
529 std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f}; // 4 dB.
530 std::atomic<bool> limiter_enabled{true};
531 StereoCompressor compressor;
532 std::atomic<float> compressor_threshold_dbfs{ref_level_dbfs - 12.0f}; // -12 dB.
533 std::atomic<bool> compressor_enabled{true};
535 double final_makeup_gain = 1.0; // Under compressor_mutex. Read/write by the user. Note: Not in dB, we want the numeric precision so that we can change it slowly.
536 bool final_makeup_gain_auto = true; // Under compressor_mutex.
538 std::unique_ptr<ALSAOutput> alsa;
544 std::mutex audio_mutex;
545 std::condition_variable audio_task_queue_changed;
546 std::queue<AudioTask> audio_task_queue; // Under audio_mutex.
548 // For mode scanning.
549 bool is_mode_scanning[MAX_CARDS]{ false };
550 std::vector<uint32_t> mode_scanlist[MAX_CARDS];
551 unsigned mode_scanlist_index[MAX_CARDS]{ 0 };
552 timespec last_mode_scan_change[MAX_CARDS];
555 extern Mixer *global_mixer;
556 extern bool uses_mlock;
558 #endif // !defined(_MIXER_H)