+++ /dev/null
-#ifndef _MIXER_H
-#define _MIXER_H 1
-
-// The actual video mixer, running in its own separate background thread.
-
-#include <assert.h>
-#include <epoxy/gl.h>
-
-#undef Success
-
-#include <stdbool.h>
-#include <stdint.h>
-#include <atomic>
-#include <chrono>
-#include <condition_variable>
-#include <cstddef>
-#include <functional>
-#include <map>
-#include <memory>
-#include <mutex>
-#include <queue>
-#include <string>
-#include <thread>
-#include <vector>
-
-#include <movit/image_format.h>
-
-#include "audio_mixer.h"
-#include "bmusb/bmusb.h"
-#include "defs.h"
-#include "httpd.h"
-#include "input_state.h"
-#include "libusb.h"
-#include "pbo_frame_allocator.h"
-#include "ref_counted_frame.h"
-#include "ref_counted_gl_sync.h"
-#include "theme.h"
-#include "timebase.h"
-#include "video_encoder.h"
-#include "ycbcr_interpretation.h"
-
-class ALSAOutput;
-class ChromaSubsampler;
-class DeckLinkOutput;
-class QSurface;
-class QSurfaceFormat;
-class TimecodeRenderer;
-class v210Converter;
-
-namespace movit {
-class Effect;
-class EffectChain;
-class ResourcePool;
-class YCbCrInput;
-} // namespace movit
-
-// A class to estimate the future jitter. Used in QueueLengthPolicy (see below).
-//
-// There are many ways to estimate jitter; I've tested a few ones (and also
-// some algorithms that don't explicitly model jitter) with different
-// parameters on some real-life data in experiments/queue_drop_policy.cpp.
-// This is one based on simple order statistics where I've added some margin in
-// the number of starvation events; I believe that about one every hour would
-// probably be acceptable, but this one typically goes lower than that, at the
-// cost of 2–3 ms extra latency. (If the queue is hard-limited to one frame, it's
-// possible to get ~10 ms further down, but this would mean framedrops every
-// second or so.) The general strategy is: Take the 99.9-percentile jitter over
-// last 5000 frames, multiply by two, and that's our worst-case jitter
-// estimate. The fact that we're not using the max value means that we could
-// actually even throw away very late frames immediately, which means we only
-// get one user-visible event instead of seeing something both when the frame
-// arrives late (duplicate frame) and then again when we drop.
-class JitterHistory {
-private:
- static constexpr size_t history_length = 5000;
- static constexpr double percentile = 0.999;
- static constexpr double multiplier = 2.0;
-
-public:
- void register_metrics(const std::vector<std::pair<std::string, std::string>> &labels);
- void unregister_metrics(const std::vector<std::pair<std::string, std::string>> &labels);
-
- void clear() {
- history.clear();
- orders.clear();
- }
- void frame_arrived(std::chrono::steady_clock::time_point now, int64_t frame_duration, size_t dropped_frames);
- std::chrono::steady_clock::time_point get_expected_next_frame() const { return expected_timestamp; }
- double estimate_max_jitter() const;
-
-private:
- // A simple O(k) based algorithm for getting the k-th largest or
- // smallest element from our window; we simply keep the multiset
- // ordered (insertions and deletions are O(n) as always) and then
- // iterate from one of the sides. If we had larger values of k,
- // we could go for a more complicated setup with two sets or heaps
- // (one increasing and one decreasing) that we keep balanced around
- // the point, or it is possible to reimplement std::set with
- // counts in each node. However, since k=5, we don't need this.
- std::multiset<double> orders;
- std::deque<std::multiset<double>::iterator> history;
-
- std::chrono::steady_clock::time_point expected_timestamp = std::chrono::steady_clock::time_point::min();
-
- // Metrics. There are no direct summaries for jitter, since we already have latency summaries.
- std::atomic<int64_t> metric_input_underestimated_jitter_frames{0};
- std::atomic<double> metric_input_estimated_max_jitter_seconds{0.0 / 0.0};
-};
-
-// For any card that's not the master (where we pick out the frames as they
-// come, as fast as we can process), there's going to be a queue. The question
-// is when we should drop frames from that queue (apart from the obvious
-// dropping if the 16-frame queue should become full), especially given that
-// the frame rate could be lower or higher than the master (either subtly or
-// dramatically). We have two (conflicting) demands:
-//
-// 1. We want to avoid starving the queue.
-// 2. We don't want to add more delay than is needed.
-//
-// Our general strategy is to drop as many frames as we can (helping for #2)
-// that we think is safe for #1 given jitter. To this end, we measure the
-// deviation from the expected arrival time for all cards, and use that for
-// continuous jitter estimation.
-//
-// We then drop everything from the queue that we're sure we won't need to
-// serve the output in the time before the next frame arrives. Typically,
-// this means the queue will contain 0 or 1 frames, although more is also
-// possible if the jitter is very high.
-class QueueLengthPolicy {
-public:
- QueueLengthPolicy() {}
- void reset(unsigned card_index) {
- this->card_index = card_index;
- }
-
- void register_metrics(const std::vector<std::pair<std::string, std::string>> &labels);
- void unregister_metrics(const std::vector<std::pair<std::string, std::string>> &labels);
-
- // Call after picking out a frame, so 0 means starvation.
- void update_policy(std::chrono::steady_clock::time_point now,
- std::chrono::steady_clock::time_point expected_next_frame,
- int64_t input_frame_duration,
- int64_t master_frame_duration,
- double max_input_card_jitter_seconds,
- double max_master_card_jitter_seconds);
- unsigned get_safe_queue_length() const { return safe_queue_length; }
-
-private:
- unsigned card_index; // For debugging and metrics only.
- unsigned safe_queue_length = 0; // Can never go below zero.
-
- // Metrics.
- std::atomic<int64_t> metric_input_queue_safe_length_frames{1};
-};
-
-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);
- }
-
- // NOTE: Callbacks will be called with a mutex held, so you should probably
- // not do real work in them.
- typedef std::function<void()> new_frame_ready_callback_t;
- void add_frame_ready_callback(Output output, void *key, new_frame_ready_callback_t callback)
- {
- output_channel[output].add_frame_ready_callback(key, callback);
- }
-
- void remove_frame_ready_callback(Output output, void *key)
- {
- output_channel[output].remove_frame_ready_callback(key);
- }
-
- // 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);
- }
-
- 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_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);
- }
-
- YCbCrInterpretation get_input_ycbcr_interpretation(unsigned card_index) const;
- void set_input_ycbcr_interpretation(unsigned card_index, const YCbCrInterpretation &interpretation);
-
- 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);
- }
-
- // Note: You can also get this through the global variable global_audio_mixer.
- AudioMixer *get_audio_mixer() { return audio_mixer.get(); }
- const AudioMixer *get_audio_mixer() const { return audio_mixer.get(); }
-
- void schedule_cut()
- {
- should_cut = true;
- }
-
- 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();
- }
-
- // The difference between this and the previous function is that if a card
- // is used as the current output, get_card_description() will return the
- // fake card that's replacing it for input, whereas this function will return
- // the card's actual name.
- std::string get_output_card_description(unsigned card_index) const {
- assert(card_can_be_used_as_output(card_index));
- assert(card_index < num_cards);
- if (cards[card_index].parked_capture) {
- return cards[card_index].parked_capture->get_description();
- } else {
- return cards[card_index].capture->get_description();
- }
- }
-
- bool card_can_be_used_as_output(unsigned card_index) const {
- assert(card_index < num_cards);
- return cards[card_index].output != nullptr;
- }
-
- bool card_is_ffmpeg(unsigned card_index) const {
- assert(card_index < num_cards + num_video_inputs);
- return cards[card_index].type == CardType::FFMPEG_INPUT;
- }
-
- 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);
- }
-
- std::string get_ffmpeg_filename(unsigned card_index) const;
-
- void set_ffmpeg_filename(unsigned card_index, const std::string &filename);
-
- void change_x264_bitrate(unsigned rate_kbit) {
- video_encoder->change_x264_bitrate(rate_kbit);
- }
-
- int get_output_card_index() const { // -1 = no output, just stream.
- return desired_output_card_index;
- }
-
- void set_output_card(int card_index) { // -1 = no output, just stream.
- desired_output_card_index = card_index;
- }
-
- std::map<uint32_t, bmusb::VideoMode> get_available_output_video_modes() const;
-
- uint32_t get_output_video_mode() const {
- return desired_output_video_mode;
- }
-
- void set_output_video_mode(uint32_t mode) {
- desired_output_video_mode = mode;
- }
-
- void set_display_timecode_in_stream(bool enable) {
- display_timecode_in_stream = enable;
- }
-
- void set_display_timecode_on_stdout(bool enable) {
- display_timecode_on_stdout = enable;
- }
-
- int64_t get_num_connected_clients() const {
- return httpd.get_num_connected_clients();
- }
-
- std::vector<Theme::MenuEntry> get_theme_menu() { return theme->get_theme_menu(); }
-
- void theme_menu_entry_clicked(int lua_ref) { return theme->theme_menu_entry_clicked(lua_ref); }
-
- void set_theme_menu_callback(std::function<void()> callback)
- {
- theme->set_theme_menu_callback(callback);
- }
-
- void wait_for_next_frame();
-
-private:
- struct CaptureCard;
-
- enum class CardType {
- LIVE_CARD,
- FAKE_CAPTURE,
- FFMPEG_INPUT,
- CEF_INPUT,
- };
- void configure_card(unsigned card_index, bmusb::CaptureInterface *capture, CardType card_type, DeckLinkOutput *output);
- void set_output_card_internal(int card_index); // Should only be called from the mixer thread.
- 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, bool is_preroll, std::chrono::steady_clock::time_point frame_timestamp);
- std::string get_timecode_text() const;
- void render_one_frame(int64_t duration);
- void audio_thread_func();
- void release_display_frame(DisplayFrame *frame);
- double pts() { return double(pts_int) / TIMEBASE; }
- void trim_queue(CaptureCard *card, size_t safe_queue_length);
- std::pair<std::string, std::string> get_channels_json();
- std::pair<std::string, std::string> get_channel_color_http(unsigned channel_idx);
-
- HTTPD httpd;
- unsigned num_cards, num_video_inputs, num_html_inputs = 0;
-
- QSurface *mixer_surface, *h264_encoder_surface, *decklink_output_surface;
- std::unique_ptr<movit::ResourcePool> resource_pool;
- std::unique_ptr<Theme> theme;
- std::atomic<unsigned> audio_source_channel{0};
- std::atomic<int> master_clock_channel{0}; // Gets overridden by <output_card_index> if set.
- int output_card_index = -1; // -1 for none.
- uint32_t output_video_mode = -1;
-
- // The mechanics of changing the output card and modes are so intricately connected
- // with the work the mixer thread is doing. Thus, we don't change it directly,
- // we just set this variable instead, which signals to the mixer thread that
- // it should do the change before the next frame. This simplifies locking
- // considerations immensely.
- std::atomic<int> desired_output_card_index{-1};
- std::atomic<uint32_t> desired_output_video_mode{0};
-
- std::unique_ptr<movit::EffectChain> display_chain;
- std::unique_ptr<ChromaSubsampler> chroma_subsampler;
- std::unique_ptr<v210Converter> v210_converter;
- std::unique_ptr<VideoEncoder> video_encoder;
-
- std::unique_ptr<TimecodeRenderer> timecode_renderer;
- std::atomic<bool> display_timecode_in_stream{false};
- std::atomic<bool> display_timecode_on_stdout{false};
-
- // Effects part of <display_chain>. Owned by <display_chain>.
- movit::YCbCrInput *display_input;
-
- int64_t pts_int = 0; // In TIMEBASE units.
-
- mutable std::mutex frame_num_mutex;
- std::condition_variable frame_num_updated;
- unsigned frame_num = 0; // Under <frame_num_mutex>.
-
- // Accumulated errors in number of 1/TIMEBASE audio samples. If OUTPUT_FREQUENCY divided by
- // frame rate is integer, will always stay zero.
- unsigned fractional_samples = 0;
-
- mutable std::mutex card_mutex;
- bool has_bmusb_thread = false;
- struct CaptureCard {
- std::unique_ptr<bmusb::CaptureInterface> capture;
- bool is_fake_capture;
- CardType type;
- std::unique_ptr<DeckLinkOutput> output;
-
- // CEF only delivers frames when it actually has a change.
- // If we trim the queue for latency reasons, we could thus
- // end up in a situation trimming a frame that was meant to
- // be displayed for a long time, which is really suboptimal.
- // Thus, if we drop the last frame we have, may_have_dropped_last_frame
- // is set to true, and the next starvation event will trigger
- // us requestin a CEF repaint.
- bool is_cef_capture, may_have_dropped_last_frame = false;
-
- // If this card is used for output (ie., output_card_index points to it),
- // it cannot simultaneously be uesd for capture, so <capture> gets replaced
- // by a FakeCapture. However, since reconstructing the real capture object
- // with all its state can be annoying, it is not being deleted, just stopped
- // and moved here.
- std::unique_ptr<bmusb::CaptureInterface> parked_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::chrono::steady_clock::time_point received_timestamp = std::chrono::steady_clock::time_point::min();
- };
- std::deque<NewFrame> new_frames;
- std::condition_variable new_frames_changed; // Set whenever new_frames is changed.
-
- QueueLengthPolicy queue_length_policy; // Refers to the "new_frames" queue.
-
- int last_timecode = -1; // Unwrapped.
-
- JitterHistory jitter_history;
-
- // Metrics.
- std::vector<std::pair<std::string, std::string>> labels;
- std::atomic<int64_t> metric_input_received_frames{0};
- std::atomic<int64_t> metric_input_duped_frames{0};
- std::atomic<int64_t> metric_input_dropped_frames_jitter{0};
- std::atomic<int64_t> metric_input_dropped_frames_error{0};
- std::atomic<int64_t> metric_input_resets{0};
- std::atomic<int64_t> metric_input_queue_length_frames{0};
-
- std::atomic<int64_t> metric_input_has_signal_bool{-1};
- std::atomic<int64_t> metric_input_is_connected_bool{-1};
- std::atomic<int64_t> metric_input_interlaced_bool{-1};
- std::atomic<int64_t> metric_input_width_pixels{-1};
- std::atomic<int64_t> metric_input_height_pixels{-1};
- std::atomic<int64_t> metric_input_frame_rate_nom{-1};
- std::atomic<int64_t> metric_input_frame_rate_den{-1};
- std::atomic<int64_t> metric_input_sample_rate_hz{-1};
- };
- JitterHistory output_jitter_history;
- CaptureCard cards[MAX_VIDEO_CARDS]; // Protected by <card_mutex>.
- YCbCrInterpretation ycbcr_interpretation[MAX_VIDEO_CARDS]; // Protected by <card_mutex>.
- std::unique_ptr<AudioMixer> audio_mixer; // Same as global_audio_mixer (see audio_mixer.h).
- bool input_card_is_master_clock(unsigned card_index, unsigned master_card_index) const;
- struct OutputFrameInfo {
- int dropped_frames; // Since last frame.
- int num_samples; // Audio samples needed for this output frame.
- int64_t frame_duration; // In TIMEBASE units.
- bool is_preroll;
- std::chrono::steady_clock::time_point frame_timestamp;
- };
- OutputFrameInfo get_one_frame_from_each_card(unsigned master_card_index, bool master_card_is_output, CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS], bool has_new_frame[MAX_VIDEO_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 add_frame_ready_callback(void *key, new_frame_ready_callback_t callback);
- void remove_frame_ready_callback(void *key);
- 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>
- std::map<void *, new_frame_ready_callback_t> new_frame_ready_callbacks; // protected by <frame_mutex>
- 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};
-
- std::unique_ptr<ALSAOutput> alsa;
-
- struct AudioTask {
- int64_t pts_int;
- int num_samples;
- bool adjust_rate;
- std::chrono::steady_clock::time_point frame_timestamp;
- };
- 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_VIDEO_CARDS]{ false };
- std::vector<uint32_t> mode_scanlist[MAX_VIDEO_CARDS];
- unsigned mode_scanlist_index[MAX_VIDEO_CARDS]{ 0 };
- std::chrono::steady_clock::time_point last_mode_scan_change[MAX_VIDEO_CARDS];
-};
-
-extern Mixer *global_mixer;
-
-#endif // !defined(_MIXER_H)
projects / nageru / blobdiff