+class Mixer {
+public:
+ // The surface format is used for offscreen destinations for OpenGL contexts we need.
+ Mixer(const QSurfaceFormat &format, unsigned num_cards);
+ ~Mixer();
+ void start();
+ void quit();
+
+ void transition_clicked(int transition_num);
+ void channel_clicked(int preview_num);
+
+ enum Output {
+ OUTPUT_LIVE = 0,
+ OUTPUT_PREVIEW,
+ OUTPUT_INPUT0, // 1, 2, 3, up to 15 follow numerically.
+ NUM_OUTPUTS = 18
+ };
+
+ struct DisplayFrame {
+ // The chain for rendering this frame. To render a display frame,
+ // first wait for <ready_fence>, then call <setup_chain>
+ // to wire up all the inputs, and then finally call
+ // chain->render_to_screen() or similar.
+ movit::EffectChain *chain;
+ std::function<void()> setup_chain;
+
+ // Asserted when all the inputs are ready; you cannot render the chain
+ // before this.
+ RefCountedGLsync ready_fence;
+
+ // Holds on to all the input frames needed for this display frame,
+ // so they are not released while still rendering.
+ std::vector<RefCountedFrame> input_frames;
+
+ // Textures that should be released back to the resource pool
+ // when this frame disappears, if any.
+ // TODO: Refcount these as well?
+ std::vector<GLuint> temp_textures;
+ };
+ // Implicitly frees the previous one if there's a new frame available.
+ bool get_display_frame(Output output, DisplayFrame *frame) {
+ return output_channel[output].get_display_frame(frame);
+ }
+
+ typedef std::function<void()> new_frame_ready_callback_t;
+ void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
+ {
+ output_channel[output].set_frame_ready_callback(callback);
+ }
+
+ // TODO: Should this really be per-channel? Shouldn't it just be called for e.g. the live output?
+ typedef std::function<void(const std::vector<std::string> &)> transition_names_updated_callback_t;
+ void set_transition_names_updated_callback(Output output, transition_names_updated_callback_t callback)
+ {
+ output_channel[output].set_transition_names_updated_callback(callback);
+ }
+
+ typedef std::function<void(const std::string &)> name_updated_callback_t;
+ void set_name_updated_callback(Output output, name_updated_callback_t callback)
+ {
+ output_channel[output].set_name_updated_callback(callback);
+ }
+
+ typedef std::function<void(const std::string &)> color_updated_callback_t;
+ void set_color_updated_callback(Output output, color_updated_callback_t callback)
+ {
+ output_channel[output].set_color_updated_callback(callback);
+ }
+
+ typedef std::function<void(float level_lufs, float peak_db,
+ float global_level_lufs, float range_low_lufs, float range_high_lufs,
+ float gain_staging_db, float final_makeup_gain_db,
+ float correlation)> audio_level_callback_t;
+ void set_audio_level_callback(audio_level_callback_t callback)
+ {
+ audio_level_callback = callback;
+ }
+
+ std::vector<std::string> get_transition_names()
+ {
+ return theme->get_transition_names(pts());
+ }
+
+ unsigned get_num_channels() const
+ {
+ return theme->get_num_channels();
+ }
+
+ std::string get_channel_name(unsigned channel) const
+ {
+ return theme->get_channel_name(channel);
+ }
+
+ std::string get_channel_color(unsigned channel) const
+ {
+ return theme->get_channel_color(channel);
+ }
+
+ int get_channel_signal(unsigned channel) const
+ {
+ return theme->get_channel_signal(channel);
+ }
+
+ int map_signal(unsigned channel)
+ {
+ return theme->map_signal(channel);
+ }
+
+ unsigned get_audio_source() const
+ {
+ return audio_source_channel;
+ }
+
+ void set_audio_source(unsigned channel)
+ {
+ audio_source_channel = channel;
+ }
+
+ unsigned get_master_clock() const
+ {
+ return master_clock_channel;
+ }
+
+ void set_master_clock(unsigned channel)
+ {
+ master_clock_channel = channel;
+ }
+
+ void set_signal_mapping(int signal, int card)
+ {
+ return theme->set_signal_mapping(signal, card);
+ }
+
+ bool get_supports_set_wb(unsigned channel) const
+ {
+ return theme->get_supports_set_wb(channel);
+ }
+
+ void set_wb(unsigned channel, double r, double g, double b) const
+ {
+ theme->set_wb(channel, r, g, b);
+ }
+
+ void set_locut_cutoff(float cutoff_hz)
+ {
+ locut_cutoff_hz = cutoff_hz;
+ }
+
+ void set_locut_enabled(bool enabled)
+ {
+ locut_enabled = enabled;
+ }
+
+ bool get_locut_enabled() const
+ {
+ return locut_enabled;
+ }
+
+ float get_limiter_threshold_dbfs()
+ {
+ return limiter_threshold_dbfs;
+ }
+
+ float get_compressor_threshold_dbfs()
+ {
+ return compressor_threshold_dbfs;
+ }
+
+ void set_limiter_threshold_dbfs(float threshold_dbfs)
+ {
+ limiter_threshold_dbfs = threshold_dbfs;
+ }
+
+ void set_compressor_threshold_dbfs(float threshold_dbfs)
+ {
+ compressor_threshold_dbfs = threshold_dbfs;
+ }
+
+ void set_limiter_enabled(bool enabled)
+ {
+ limiter_enabled = enabled;
+ }
+
+ bool get_limiter_enabled() const
+ {
+ return limiter_enabled;
+ }
+
+ void set_compressor_enabled(bool enabled)
+ {
+ compressor_enabled = enabled;
+ }
+
+ bool get_compressor_enabled() const
+ {
+ return compressor_enabled;
+ }
+
+ void set_gain_staging_db(float gain_db)
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ level_compressor_enabled = false;
+ gain_staging_db = gain_db;
+ }
+
+ float get_gain_staging_db() const
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ return gain_staging_db;
+ }
+
+ void set_gain_staging_auto(bool enabled)
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ level_compressor_enabled = enabled;
+ }
+
+ bool get_gain_staging_auto() const
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ return level_compressor_enabled;
+ }
+
+ void set_final_makeup_gain_db(float gain_db)
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ final_makeup_gain_auto = false;
+ final_makeup_gain = pow(10.0f, gain_db / 20.0f);
+ }
+
+ void set_final_makeup_gain_auto(bool enabled)
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ final_makeup_gain_auto = enabled;
+ }
+
+ bool get_final_makeup_gain_auto() const
+ {
+ std::unique_lock<std::mutex> lock(compressor_mutex);
+ return final_makeup_gain_auto;
+ }
+
+ void schedule_cut()
+ {
+ should_cut = true;
+ }
+
+ void reset_meters();
+
+ unsigned get_num_cards() const { return num_cards; }
+
+ std::string get_card_description(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_description();
+ }
+
+ std::map<uint32_t, bmusb::VideoMode> get_available_video_modes(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_available_video_modes();
+ }
+
+ uint32_t get_current_video_mode(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_current_video_mode();
+ }
+
+ void set_video_mode(unsigned card_index, uint32_t mode) {
+ assert(card_index < num_cards);
+ cards[card_index].capture->set_video_mode(mode);
+ }
+
+ void start_mode_scanning(unsigned card_index);
+
+ std::map<uint32_t, std::string> get_available_video_inputs(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_available_video_inputs();
+ }
+
+ uint32_t get_current_video_input(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_current_video_input();
+ }
+
+ void set_video_input(unsigned card_index, uint32_t input) {
+ assert(card_index < num_cards);
+ cards[card_index].capture->set_video_input(input);
+ }
+
+ std::map<uint32_t, std::string> get_available_audio_inputs(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_available_audio_inputs();
+ }
+
+ uint32_t get_current_audio_input(unsigned card_index) const {
+ assert(card_index < num_cards);
+ return cards[card_index].capture->get_current_audio_input();
+ }
+
+ void set_audio_input(unsigned card_index, uint32_t input) {
+ assert(card_index < num_cards);
+ cards[card_index].capture->set_audio_input(input);
+ }
+
+ void change_x264_bitrate(unsigned rate_kbit) {
+ video_encoder->change_x264_bitrate(rate_kbit);
+ }
+
+private:
+ void configure_card(unsigned card_index, bmusb::CaptureInterface *capture, bool is_fake_capture);
+ void bm_frame(unsigned card_index, uint16_t timecode,
+ bmusb::FrameAllocator::Frame video_frame, size_t video_offset, bmusb::VideoFormat video_format,
+ bmusb::FrameAllocator::Frame audio_frame, size_t audio_offset, bmusb::AudioFormat audio_format);
+ void bm_hotplug_add(libusb_device *dev);
+ void bm_hotplug_remove(unsigned card_index);
+ void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
+ void thread_func();
+ void handle_hotplugged_cards();
+ void schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame);
+ void render_one_frame(int64_t duration);
+ void send_audio_level_callback();
+ void audio_thread_func();
+ void process_audio_one_frame(int64_t frame_pts_int, int num_samples);
+ void subsample_chroma(GLuint src_tex, GLuint dst_dst);
+ void release_display_frame(DisplayFrame *frame);
+ double pts() { return double(pts_int) / TIMEBASE; }
+
+ HTTPD httpd;
+ unsigned num_cards;
+
+ QSurface *mixer_surface, *h264_encoder_surface;
+ std::unique_ptr<movit::ResourcePool> resource_pool;
+ std::unique_ptr<Theme> theme;
+ std::atomic<unsigned> audio_source_channel{0};
+ std::atomic<unsigned> master_clock_channel{0};
+ std::unique_ptr<movit::EffectChain> display_chain;
+ GLuint cbcr_program_num; // Owned by <resource_pool>.
+ GLuint cbcr_vbo; // Holds position and texcoord data.
+ GLuint cbcr_position_attribute_index, cbcr_texcoord_attribute_index;
+ std::unique_ptr<VideoEncoder> video_encoder;
+
+ // Effects part of <display_chain>. Owned by <display_chain>.
+ movit::FlatInput *display_input;
+
+ int64_t pts_int = 0; // In TIMEBASE units.
+
+ std::mutex bmusb_mutex;
+ bool has_bmusb_thread = false;
+ struct CaptureCard {
+ bmusb::CaptureInterface *capture = nullptr;
+ bool is_fake_capture;
+ std::unique_ptr<PBOFrameAllocator> frame_allocator;
+
+ // Stuff for the OpenGL context (for texture uploading).
+ QSurface *surface = nullptr;
+
+ struct NewFrame {
+ RefCountedFrame frame;
+ int64_t length; // In TIMEBASE units.
+ bool interlaced;
+ unsigned field; // Which field (0 or 1) of the frame to use. Always 0 for progressive.
+ std::function<void()> upload_func; // Needs to be called to actually upload the texture to OpenGL.
+ unsigned dropped_frames = 0; // Number of dropped frames before this one.
+ };
+ std::queue<NewFrame> new_frames;
+ bool should_quit = false;
+ std::condition_variable new_frames_changed; // Set whenever new_frames (or should_quit) is changed.
+
+ QueueLengthPolicy queue_length_policy; // Refers to the "new_frames" queue.
+
+ // Accumulated errors in number of 1/TIMEBASE samples. If OUTPUT_FREQUENCY divided by
+ // frame rate is integer, will always stay zero.
+ unsigned fractional_samples = 0;
+
+ std::mutex audio_mutex;
+ std::unique_ptr<ResamplingQueue> resampling_queue; // Under audio_mutex.
+ int last_timecode = -1; // Unwrapped.
+ int64_t next_local_pts = 0; // Beginning of next frame, in TIMEBASE units.
+ };
+ CaptureCard cards[MAX_CARDS]; // protected by <bmusb_mutex>
+ 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]);
+
+ InputState input_state;
+
+ // Cards we have been noticed about being hotplugged, but haven't tried adding yet.
+ // Protected by its own mutex.
+ std::mutex hotplug_mutex;
+ std::vector<libusb_device *> hotplugged_cards;
+
+ class OutputChannel {
+ public:
+ ~OutputChannel();
+ void output_frame(DisplayFrame frame);
+ bool get_display_frame(DisplayFrame *frame);
+ void set_frame_ready_callback(new_frame_ready_callback_t callback);
+ void set_transition_names_updated_callback(transition_names_updated_callback_t callback);
+ void set_name_updated_callback(name_updated_callback_t callback);
+ void set_color_updated_callback(color_updated_callback_t callback);
+
+ private:
+ friend class Mixer;
+
+ unsigned channel;
+ Mixer *parent = nullptr; // Not owned.
+ std::mutex frame_mutex;
+ DisplayFrame current_frame, ready_frame; // protected by <frame_mutex>
+ bool has_current_frame = false, has_ready_frame = false; // protected by <frame_mutex>
+ new_frame_ready_callback_t new_frame_ready_callback;
+ transition_names_updated_callback_t transition_names_updated_callback;
+ name_updated_callback_t name_updated_callback;
+ color_updated_callback_t color_updated_callback;
+
+ std::vector<std::string> last_transition_names;
+ std::string last_name, last_color;
+ };
+ OutputChannel output_channel[NUM_OUTPUTS];
+
+ std::thread mixer_thread;
+ std::thread audio_thread;
+ std::atomic<bool> should_quit{false};
+ std::atomic<bool> should_cut{false};
+
+ audio_level_callback_t audio_level_callback = nullptr;
+ mutable std::mutex compressor_mutex;
+ Ebu_r128_proc r128; // Under compressor_mutex.
+ CorrelationMeasurer correlation; // Under compressor_mutex.
+
+ Resampler peak_resampler;
+ std::atomic<float> peak{0.0f};
+
+ StereoFilter locut; // Default cutoff 120 Hz, 24 dB/oct.
+ std::atomic<float> locut_cutoff_hz;
+ std::atomic<bool> locut_enabled{true};
+
+ // First compressor; takes us up to about -12 dBFS.
+ StereoCompressor level_compressor; // Under compressor_mutex. Used to set/override gain_staging_db if <level_compressor_enabled>.
+ float gain_staging_db = 0.0f; // Under compressor_mutex.
+ bool level_compressor_enabled = true; // Under compressor_mutex.
+
+ static constexpr float ref_level_dbfs = -14.0f; // Chosen so that we end up around 0 LU in practice.
+ static constexpr float ref_level_lufs = -23.0f; // 0 LU, more or less by definition.
+
+ StereoCompressor limiter;
+ std::atomic<float> limiter_threshold_dbfs{ref_level_dbfs + 4.0f}; // 4 dB.
+ std::atomic<bool> limiter_enabled{true};
+ StereoCompressor compressor;
+ std::atomic<float> compressor_threshold_dbfs{ref_level_dbfs - 12.0f}; // -12 dB.
+ std::atomic<bool> compressor_enabled{true};
+
+ 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.
+ bool final_makeup_gain_auto = true; // Under compressor_mutex.
+
+ std::unique_ptr<ALSAOutput> alsa;
+
+ struct AudioTask {
+ int64_t pts_int;
+ int num_samples;
+ };
+ std::mutex audio_mutex;
+ std::condition_variable audio_task_queue_changed;
+ std::queue<AudioTask> audio_task_queue; // Under audio_mutex.
+
+ // For mode scanning.
+ bool is_mode_scanning[MAX_CARDS]{ false };
+ std::vector<uint32_t> mode_scanlist[MAX_CARDS];
+ unsigned mode_scanlist_index[MAX_CARDS]{ 0 };
+ timespec last_mode_scan_change[MAX_CARDS];