class QOpenGLContext;
class QSurfaceFormat;
+// 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 set a lower floor N,
+// where we assume that if we have N frames in the queue, we're always safe from
+// starvation. (Typically, N will be 0 or 1. It starts off at 0.) If we have
+// more than N frames in the queue after reading out the one we need, we head-drop
+// them to reduce the queue.
+//
+// N is reduced as follows: If the queue has had at least one spare frame for
+// at least 50 (master) frames (ie., it's been too conservative for a second),
+// we reduce N by 1 and reset the timers. TODO: Only do this if N ever actually
+// touched the limit.
+//
+// Whenever the queue is starved (we needed a frame but there was none),
+// and we've been at N since the last starvation, N was obviously too low,
+// so we increment it. We will never set N above 5, though.
+class QueueLengthPolicy {
+public:
+ QueueLengthPolicy() {}
+ void reset(unsigned card_index) {
+ this->card_index = card_index;
+ safe_queue_length = 0;
+ frames_with_at_least_one = 0;
+ been_at_safe_point_since_last_starvation = false;
+ }
+
+ void update_policy(int queue_length); // Give in -1 for starvation.
+ unsigned get_safe_queue_length() const { return safe_queue_length; }
+
+private:
+ unsigned card_index; // For debugging only.
+ unsigned safe_queue_length = 0; // Called N in the comments.
+ unsigned frames_with_at_least_one = 0;
+ bool been_at_safe_point_since_last_starvation = false;
+};
+
class Mixer {
public:
// The surface format is used for offscreen destinations for OpenGL contexts we need.
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);
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);
return cards[card_index].capture->get_description();
}
+ std::map<uint32_t, 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);
+ }
+
private:
+ void configure_card(unsigned card_index, const QSurfaceFormat &format, CaptureInterface *capture);
void bm_frame(unsigned card_index, uint16_t timecode,
FrameAllocator::Frame video_frame, size_t video_offset, VideoFormat video_format,
- FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format);
+ FrameAllocator::Frame audio_frame, size_t audio_offset, AudioFormat audio_format);
void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
void thread_func();
+ void schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame);
+ void render_one_frame();
+ 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);
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.
QSurface *surface;
QOpenGLContext *context;
- bool new_data_ready = false; // Whether new_frame contains anything.
+ 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.
+ RefCountedGLsync ready_fence; // Whether frame is ready for rendering.
+ unsigned dropped_frames = 0; // Number of dropped frames before this one.
+ };
+ std::queue<NewFrame> new_frames;
bool should_quit = false;
- RefCountedFrame new_frame;
- int64_t new_frame_length; // In TIMEBASE units.
- bool new_frame_interlaced;
- unsigned new_frame_field; // Which field (0 or 1) of the frame to use. Always 0 for progressive.
- GLsync new_data_ready_fence; // Whether new_frame is ready for rendering.
- std::condition_variable new_data_ready_changed; // Set whenever new_data_ready is changed.
- unsigned dropped_frames = 0; // Before new_frame.
+ 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.
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;
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];
};
extern Mixer *global_mixer;
projects / nageru / blobdiff