#include <movit/image_format.h>
#include <movit/init.h>
#include <movit/resource_pool.h>
+#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
} // namespace
-void QueueLengthPolicy::update_policy(int queue_length)
+void QueueLengthPolicy::update_policy(unsigned queue_length)
{
- if (queue_length < 0) { // Starvation.
- if (been_at_safe_point_since_last_starvation && safe_queue_length < 5) {
+ if (queue_length == 0) { // Starvation.
+ if (been_at_safe_point_since_last_starvation && safe_queue_length < global_flags.max_input_queue_frames) {
++safe_queue_length;
- fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frames\n",
+ fprintf(stderr, "Card %u: Starvation, increasing safe limit to %u frame(s)\n",
card_index, safe_queue_length);
}
frames_with_at_least_one = 0;
been_at_safe_point_since_last_starvation = false;
return;
}
- if (queue_length > 0) {
- if (queue_length >= int(safe_queue_length)) {
+ if (queue_length >= 1) {
+ if (queue_length >= safe_queue_length) {
been_at_safe_point_since_last_starvation = true;
}
- if (++frames_with_at_least_one >= 1000 && safe_queue_length > 0) {
+ if (++frames_with_at_least_one >= 1000 && safe_queue_length > 1) {
--safe_queue_length;
- fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frames\n",
+ fprintf(stderr, "Card %u: Spare frames for more than 1000 frames, reducing safe limit to %u frame(s)\n",
card_index, safe_queue_length);
frames_with_at_least_one = 0;
}
alsa.reset(new ALSAOutput(OUTPUT_FREQUENCY, /*num_channels=*/2));
}
if (global_flags.output_card != -1) {
- set_output_card(global_flags.output_card);
+ desired_output_card_index = global_flags.output_card;
+ set_output_card_internal(global_flags.output_card);
}
}
if (card->surface == nullptr) {
card->surface = create_surface_with_same_format(mixer_surface);
}
- while (!card->new_frames.empty()) card->new_frames.pop();
+ while (!card->new_frames.empty()) card->new_frames.pop_front();
card->last_timecode = -1;
card->capture->configure_card();
audio_mixer.trigger_state_changed_callback();
}
-void Mixer::set_output_card(int card_index)
+void Mixer::set_output_card_internal(int card_index)
{
- if (card_index == output_card_index) {
- return;
- }
+ // We don't really need to take card_mutex, since we're in the mixer
+ // thread and don't mess with any queues (which is the only thing that happens
+ // from other threads), but it's probably the safest in the long run.
unique_lock<mutex> lock(card_mutex);
if (output_card_index != -1) {
// Switch the old card from output to input.
old_card->is_fake_capture = false;
old_card->capture->start_bm_capture();
}
-
- CaptureCard *card = &cards[card_index];
- bmusb::CaptureInterface *capture = card->capture.get();
- lock.unlock();
- capture->stop_dequeue_thread();
- lock.lock();
- card->parked_capture = move(card->capture);
- bmusb::CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
- configure_card(card_index, fake_capture, /*is_fake_capture=*/true, card->output.release());
- card->queue_length_policy.reset(card_index);
- card->capture->start_bm_capture();
- card->output->start_output(bmdModeHD720p5994, pts_int); // FIXME
+ if (card_index != -1) {
+ CaptureCard *card = &cards[card_index];
+ bmusb::CaptureInterface *capture = card->capture.get();
+ // TODO: DeckLinkCapture::stop_dequeue_thread can actually take
+ // several seconds to complete (blocking on DisableVideoInput);
+ // see if we can maybe do it asynchronously.
+ lock.unlock();
+ capture->stop_dequeue_thread();
+ lock.lock();
+ card->parked_capture = move(card->capture);
+ bmusb::CaptureInterface *fake_capture = new FakeCapture(global_flags.width, global_flags.height, FAKE_FPS, OUTPUT_FREQUENCY, card_index, global_flags.fake_cards_audio);
+ configure_card(card_index, fake_capture, /*is_fake_capture=*/true, card->output.release());
+ card->queue_length_policy.reset(card_index);
+ card->capture->start_bm_capture();
+ desired_output_video_mode = output_video_mode = card->output->pick_video_mode(desired_output_video_mode);
+ card->output->start_output(desired_output_video_mode, pts_int);
+ }
output_card_index = card_index;
}
} while (!success);
}
- audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length);
+ audio_mixer.add_audio(device, audio_frame.data + audio_offset, num_samples, audio_format, frame_length, audio_frame.received_timestamp);
// Done with the audio, so release it.
if (audio_frame.owner) {
new_frame.length = frame_length;
new_frame.interlaced = false;
new_frame.dropped_frames = dropped_frames;
- card->new_frames.push(move(new_frame));
+ card->new_frames.push_back(move(new_frame));
card->new_frames_changed.notify_all();
}
return;
new_frame.upload_func = upload_func;
new_frame.dropped_frames = dropped_frames;
new_frame.received_timestamp = video_frame.received_timestamp; // Ignore the audio timestamp.
- card->new_frames.push(move(new_frame));
+ card->new_frames.push_back(move(new_frame));
card->new_frames_changed.notify_all();
}
}
void Mixer::thread_func()
{
+ pthread_setname_np(pthread_self(), "Mixer_OpenGL");
+
eglBindAPI(EGL_OPENGL_API);
QOpenGLContext *context = create_context(mixer_surface);
if (!make_current(context, mixer_surface)) {
int stats_dropped_frames = 0;
while (!should_quit) {
+ if (desired_output_card_index != output_card_index) {
+ set_output_card_internal(desired_output_card_index);
+ }
+ if (output_card_index != -1 &&
+ desired_output_video_mode != output_video_mode) {
+ DeckLinkOutput *output = cards[output_card_index].output.get();
+ output->end_output();
+ desired_output_video_mode = output_video_mode = output->pick_video_mode(desired_output_video_mode);
+ output->start_output(desired_output_video_mode, pts_int);
+ }
+
CaptureCard::NewFrame new_frames[MAX_VIDEO_CARDS];
bool has_new_frame[MAX_VIDEO_CARDS] = { false };
}
OutputFrameInfo output_frame_info = get_one_frame_from_each_card(master_card_index, master_card_is_output, new_frames, has_new_frame);
- schedule_audio_resampling_tasks(output_frame_info.dropped_frames, output_frame_info.num_samples, output_frame_info.frame_duration);
+ schedule_audio_resampling_tasks(output_frame_info.dropped_frames, output_frame_info.num_samples, output_frame_info.frame_duration, output_frame_info.is_preroll, output_frame_info.frame_timestamp);
stats_dropped_frames += output_frame_info.dropped_frames;
handle_hotplugged_cards();
return (card_index == master_card_index);
}
+void Mixer::trim_queue(CaptureCard *card, unsigned card_index)
+{
+ // Count the number of frames in the queue, including any frames
+ // we dropped. It's hard to know exactly how we should deal with
+ // dropped (corrupted) input frames; they don't help our goal of
+ // avoiding starvation, but they still add to the problem of latency.
+ // Since dropped frames is going to mean a bump in the signal anyway,
+ // we err on the side of having more stable latency instead.
+ unsigned queue_length = 0;
+ for (const CaptureCard::NewFrame &frame : card->new_frames) {
+ queue_length += frame.dropped_frames + 1;
+ }
+ card->queue_length_policy.update_policy(queue_length);
+
+ // If needed, drop frames until the queue is below the safe limit.
+ // We prefer to drop from the head, because all else being equal,
+ // we'd like more recent frames (less latency).
+ unsigned dropped_frames = 0;
+ while (queue_length > card->queue_length_policy.get_safe_queue_length()) {
+ assert(!card->new_frames.empty());
+ assert(queue_length > card->new_frames.front().dropped_frames);
+ queue_length -= card->new_frames.front().dropped_frames;
+
+ if (queue_length <= card->queue_length_policy.get_safe_queue_length()) {
+ // No need to drop anything.
+ break;
+ }
+
+ card->new_frames.pop_front();
+ card->new_frames_changed.notify_all();
+ --queue_length;
+ ++dropped_frames;
+ }
+
+ if (dropped_frames > 0) {
+ fprintf(stderr, "Card %u dropped %u frame(s) to keep latency down.\n",
+ card_index, dropped_frames);
+ }
+}
+
+
Mixer::OutputFrameInfo Mixer::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])
{
OutputFrameInfo output_frame_info;
unique_lock<mutex> lock(card_mutex, defer_lock);
if (master_card_is_output) {
// Clocked to the output, so wait for it to be ready for the next frame.
- cards[master_card_index].output->wait_for_frame(pts_int, &output_frame_info.dropped_frames, &output_frame_info.frame_duration);
+ cards[master_card_index].output->wait_for_frame(pts_int, &output_frame_info.dropped_frames, &output_frame_info.frame_duration, &output_frame_info.is_preroll, &output_frame_info.frame_timestamp);
lock.lock();
} else {
// Wait for the master card to have a new frame.
// TODO: Add a timeout.
+ output_frame_info.is_preroll = false;
lock.lock();
cards[master_card_index].new_frames_changed.wait(lock, [this, master_card_index]{ return !cards[master_card_index].new_frames.empty() || cards[master_card_index].capture->get_disconnected(); });
}
goto start;
}
+ if (!master_card_is_output) {
+ output_frame_info.frame_timestamp =
+ cards[master_card_index].new_frames.front().received_timestamp;
+ }
+
for (unsigned card_index = 0; card_index < num_cards; ++card_index) {
CaptureCard *card = &cards[card_index];
- if (card->new_frames.empty()) {
- assert(!input_card_is_master_clock(card_index, master_card_index));
- card->queue_length_policy.update_policy(-1);
- continue;
- }
- new_frames[card_index] = move(card->new_frames.front());
- has_new_frame[card_index] = true;
- card->new_frames.pop();
- card->new_frames_changed.notify_all();
-
if (input_card_is_master_clock(card_index, master_card_index)) {
// We don't use the queue length policy for the master card,
// but we will if it stops being the master. Thus, clear out
// the policy in case we switch in the future.
card->queue_length_policy.reset(card_index);
+ assert(!card->new_frames.empty());
} else {
- // If we have excess frames compared to the policy for this card,
- // drop frames from the head.
- card->queue_length_policy.update_policy(card->new_frames.size());
- while (card->new_frames.size() > card->queue_length_policy.get_safe_queue_length()) {
- card->new_frames.pop();
- }
+ trim_queue(card, card_index);
+ }
+ if (!card->new_frames.empty()) {
+ new_frames[card_index] = move(card->new_frames.front());
+ has_new_frame[card_index] = true;
+ card->new_frames.pop_front();
+ card->new_frames_changed.notify_all();
}
}
}
-void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame)
+void Mixer::schedule_audio_resampling_tasks(unsigned dropped_frames, int num_samples_per_frame, int length_per_frame, bool is_preroll, steady_clock::time_point frame_timestamp)
{
// Resample the audio as needed, including from previously dropped frames.
assert(num_cards > 0);
// since dropped frames are expected to be rare, and it might be
// better to just wait until we have a slightly more normal situation).
unique_lock<mutex> lock(audio_mutex);
- bool adjust_rate = !dropped_frame;
- audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate});
+ bool adjust_rate = !dropped_frame && !is_preroll;
+ audio_task_queue.push(AudioTask{pts_int, num_samples_per_frame, adjust_rate, frame_timestamp});
audio_task_queue_changed.notify_one();
}
if (dropped_frame) {
void Mixer::audio_thread_func()
{
+ pthread_setname_np(pthread_self(), "Mixer_Audio");
+
while (!should_quit) {
AudioTask task;
ResamplingQueue::RateAdjustmentPolicy rate_adjustment_policy =
task.adjust_rate ? ResamplingQueue::ADJUST_RATE : ResamplingQueue::DO_NOT_ADJUST_RATE;
vector<float> samples_out = audio_mixer.get_output(
- double(task.pts_int) / TIMEBASE,
+ task.frame_timestamp,
task.num_samples,
rate_adjustment_policy);
last_mode_scan_change[card_index] = steady_clock::now();
}
+map<uint32_t, bmusb::VideoMode> Mixer::get_available_output_video_modes() const
+{
+ assert(desired_output_card_index != -1);
+ unique_lock<mutex> lock(card_mutex);
+ return cards[desired_output_card_index].output->get_available_video_modes();
+}
+
Mixer::OutputChannel::~OutputChannel()
{
if (has_current_frame) {
projects / nageru / blobdiff