git.sesse.net Git - nageru/blob - player.cpp

   1 #include <algorithm>
   2 #include <chrono>
   3 #include <condition_variable>
   4 #include <mutex>
   5 #include <thread>
   6 #include <vector>
   7
   8 #include <stdio.h>
   9
  10 #include <movit/util.h>
  11
  12 #include "clip_list.h"
  13 #include "context.h"
  14 #include "defs.h"
  15 #include "ffmpeg_raii.h"
  16 #include "httpd.h"
  17 #include "jpeg_frame_view.h"
  18 #include "mux.h"
  19 #include "player.h"
  20 #include "timebase.h"
  21 #include "video_stream.h"
  22
  23 using namespace std;
  24 using namespace std::chrono;
  25
  26 extern mutex frame_mu;
  27 extern vector<int64_t> frames[MAX_STREAMS];
  28 extern HTTPD *global_httpd;
  29
  30 void Player::thread_func(bool also_output_to_stream)
  31 {
  32         pthread_setname_np(pthread_self(), "Player");
  33
  34         QSurface *surface = create_surface();
  35         QOpenGLContext *context = create_context(surface);
  36         if (!make_current(context, surface)) {
  37                 printf("oops\n");
  38                 exit(1);
  39         }
  40
  41         check_error();
  42
  43         // Create the VideoStream object, now that we have an OpenGL context.
  44         if (also_output_to_stream) {
  45                 video_stream.reset(new VideoStream);
  46                 video_stream->start();
  47         }
  48
  49         check_error();
  50
  51         constexpr double output_framerate = 60000.0 / 1001.0;  // FIXME: make configurable
  52         int64_t pts = 0;
  53         Clip next_clip;
  54         bool got_next_clip = false;
  55         double next_clip_fade_time = -1.0;
  56
  57         for ( ;; ) {
  58                 bool clip_ready;
  59                 steady_clock::time_point before_sleep = steady_clock::now();
  60
  61                 // Wait until we're supposed to play something.
  62                 {
  63                         unique_lock<mutex> lock(queue_state_mu);
  64                         clip_ready = new_clip_changed.wait_for(lock, milliseconds(100), [this]{
  65                                 return new_clip_ready && current_clip.pts_in != -1;
  66                         });
  67                         new_clip_ready = false;
  68                         playing = true;
  69                 }
  70
  71                 steady_clock::duration time_slept = steady_clock::now() - before_sleep;
  72                 pts += duration_cast<duration<size_t, TimebaseRatio>>(time_slept).count();
  73
  74                 if (!clip_ready) {
  75                         if (video_stream != nullptr) {
  76                                 video_stream->schedule_refresh_frame(pts);
  77                         }
  78                         continue;
  79                 }
  80
  81                 Clip clip;
  82                 unsigned stream_idx;
  83                 {
  84                         lock_guard<mutex> lock(mu);
  85                         clip = current_clip;
  86                         stream_idx = current_stream_idx;
  87                 }
  88                 steady_clock::time_point origin = steady_clock::now();
  89                 int64_t in_pts_origin = clip.pts_in;
  90 got_clip:
  91                 int64_t out_pts_origin = pts;
  92
  93                 // Start playing exactly at a frame.
  94                 // TODO: Snap secondary (fade-to) clips in the same fashion
  95                 // so that we don't get jank here).
  96                 {
  97                         lock_guard<mutex> lock(frame_mu);
  98
  99                         // Find the first frame such that frame.pts <= in_pts.
 100                         auto it = lower_bound(frames[stream_idx].begin(),
 101                                 frames[stream_idx].end(),
 102                                 in_pts_origin);
 103                         if (it != frames[stream_idx].end()) {
 104                                 in_pts_origin = *it;
 105                         }
 106                 }
 107
 108                 // TODO: Lock to a rational multiple of the frame rate if possible.
 109                 double speed = 0.5;
 110
 111                 int64_t in_pts_start_next_clip = -1;
 112                 for (int frameno = 0; ; ++frameno) {  // Ends when the clip ends.
 113                         double out_pts = out_pts_origin + TIMEBASE * frameno / output_framerate;
 114                         steady_clock::time_point next_frame_start =
 115                                 origin + microseconds(lrint((out_pts - out_pts_origin) * 1e6 / TIMEBASE));
 116                         int64_t in_pts = lrint(in_pts_origin + TIMEBASE * frameno * speed / output_framerate);
 117                         pts = lrint(out_pts);
 118
 119                         steady_clock::duration time_behind = steady_clock::now() - next_frame_start;
 120                         if (time_behind >= milliseconds(200)) {
 121                                 fprintf(stderr, "WARNING: %ld ms behind, dropping a frame (no matter the type).\n",
 122                                         lrint(1e3 * duration<double>(time_behind).count()));
 123                                 continue;
 124                         }
 125
 126                         double time_left_this_clip = double(clip.pts_out - in_pts) / TIMEBASE / speed;
 127                         if (!got_next_clip && next_clip_callback != nullptr && time_left_this_clip <= clip.fade_time_seconds) {
 128                                 // Find the next clip so that we can begin a fade.
 129                                 next_clip = next_clip_callback();
 130                                 if (next_clip.pts_in != -1) {
 131                                         got_next_clip = true;
 132
 133                                         double duration_next_clip = (next_clip.pts_out - next_clip.pts_in) / TIMEBASE / speed;
 134                                         next_clip_fade_time = std::min(time_left_this_clip, duration_next_clip);
 135                                         in_pts_start_next_clip = next_clip.pts_in + lrint(next_clip_fade_time * TIMEBASE * speed);
 136                                 }
 137                         }
 138
 139                         int primary_stream_idx = stream_idx;
 140                         int secondary_stream_idx = -1;
 141                         float fade_alpha = 0.0f;
 142                         if (got_next_clip) {
 143                                 secondary_stream_idx = next_clip.stream_idx;
 144                                 fade_alpha = 1.0f - time_left_this_clip / next_clip_fade_time;
 145
 146                                 // If more than half-way through the fade, interpolate the next clip
 147                                 // instead of the current one, since it's more visible.
 148                                 if (fade_alpha >= 0.5f) {
 149                                         swap(primary_stream_idx, secondary_stream_idx);
 150                                         fade_alpha = 1.0f - fade_alpha;
 151                                 }
 152                         }
 153
 154                         int64_t secondary_pts = -1;
 155                         if (got_next_clip) {
 156                                 int64_t in_pts_secondary = lrint(next_clip.pts_in + TIMEBASE * frameno * speed / output_framerate);
 157                                 int64_t in_pts_lower, in_pts_upper;
 158                                 bool ok = find_surrounding_frames(in_pts_secondary, secondary_stream_idx, &in_pts_lower, &in_pts_upper);
 159                                 if (ok) {
 160                                         secondary_pts = in_pts_lower;
 161                                 } else {
 162                                         secondary_stream_idx = -1;
 163                                 }
 164                         }
 165
 166                         if (progress_callback != nullptr) {
 167                                 // NOTE: None of this will take into account any snapping done below.
 168                                 double played_this_clip = double(in_pts - clip.pts_in) / TIMEBASE / speed;
 169                                 double total_length = double(clip.pts_out - clip.pts_in) / TIMEBASE / speed;
 170                                 progress_callback(played_this_clip, total_length);
 171                         }
 172
 173                         int64_t in_pts_lower, in_pts_upper;
 174                         bool ok = find_surrounding_frames(in_pts, primary_stream_idx, &in_pts_lower, &in_pts_upper);
 175                         if (!ok || in_pts_upper >= clip.pts_out) {
 176                                 break;
 177                         }
 178
 179                         // Sleep until the next frame start, or until there's a new clip we're supposed to play.
 180                         {
 181                                 unique_lock<mutex> lock(queue_state_mu);
 182                                 new_clip_changed.wait_until(lock, next_frame_start, [this]{
 183                                         return new_clip_ready || override_stream_idx != -1;
 184                                 });
 185                                 if (new_clip_ready) break;
 186                                 if (override_stream_idx != -1) {
 187                                         stream_idx = override_stream_idx;
 188                                         override_stream_idx = -1;
 189                                         continue;
 190                                 }
 191                         }
 192
 193                         if (in_pts_lower == in_pts_upper) {
 194                                 destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 195                                 if (video_stream != nullptr) {
 196                                         if (secondary_stream_idx == -1) {
 197                                                 video_stream->schedule_original_frame(pts, primary_stream_idx, in_pts_lower);
 198                                         } else {
 199                                                 video_stream->schedule_faded_frame(pts, primary_stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha);
 200                                         }
 201                                 }
 202                                 continue;
 203                         }
 204
 205                         // Snap to input frame: If we can do so with less than 1% jitter
 206                         // (ie., move less than 1% of an _output_ frame), do so.
 207                         // TODO: Snap secondary (fade-to) clips in the same fashion.
 208                         bool snapped = false;
 209                         for (int64_t snap_pts : { in_pts_lower, in_pts_upper }) {
 210                                 double snap_pts_as_frameno = (snap_pts - in_pts_origin) * output_framerate / TIMEBASE / speed;
 211                                 if (fabs(snap_pts_as_frameno - frameno) < 0.01) {
 212                                         destination->setFrame(primary_stream_idx, snap_pts, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 213                                         if (video_stream != nullptr) {
 214                                                 if (secondary_stream_idx == -1) {
 215                                                         video_stream->schedule_original_frame(pts, primary_stream_idx, snap_pts);
 216                                                 } else {
 217                                                         video_stream->schedule_faded_frame(pts, primary_stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha);
 218                                                 }
 219                                         }
 220                                         in_pts_origin += snap_pts - in_pts;
 221                                         snapped = true;
 222                                         break;
 223                                 }
 224                         }
 225                         if (snapped) {
 226                                 continue;
 227                         }
 228
 229                         if (time_behind >= milliseconds(100)) {
 230                                 fprintf(stderr, "WARNING: %ld ms behind, dropping an interpolated frame.\n",
 231                                         lrint(1e3 * duration<double>(time_behind).count()));
 232                                 continue;
 233                         }
 234
 235                         double alpha = double(in_pts - in_pts_lower) / (in_pts_upper - in_pts_lower);
 236
 237                         if (video_stream == nullptr) {
 238                                 // Previews don't do any interpolation.
 239                                 assert(secondary_stream_idx == -1);
 240                                 destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false);
 241                         } else {
 242                                 // Calculate the interpolated frame. When it's done, the destination
 243                                 // will be unblocked.
 244                                 destination->setFrame(primary_stream_idx, pts, /*interpolated=*/true, secondary_stream_idx, secondary_pts, fade_alpha);
 245                                 video_stream->schedule_interpolated_frame(pts, primary_stream_idx, in_pts_lower, in_pts_upper, alpha, secondary_stream_idx, secondary_pts, fade_alpha);
 246                         }
 247                 }
 248
 249                 // The clip ended.
 250
 251                 // Last-ditch effort to get the next clip (if e.g. the fade time was zero seconds).
 252                 if (!got_next_clip && next_clip_callback != nullptr) {
 253                         next_clip = next_clip_callback();
 254                         if (next_clip.pts_in != -1) {
 255                                 got_next_clip = true;
 256                                 in_pts_start_next_clip = next_clip.pts_in;
 257                         }
 258                 }
 259
 260                 // Switch to next clip if we got it.
 261                 if (got_next_clip) {
 262                         clip = next_clip;
 263                         stream_idx = next_clip.stream_idx;  // Override is used for previews only, and next_clip is used for live ony.
 264                         if (done_callback != nullptr) {
 265                                 done_callback();
 266                         }
 267                         got_next_clip = false;
 268
 269                         // Start the next clip from the point where the fade went out.
 270                         origin = steady_clock::now();
 271                         in_pts_origin = in_pts_start_next_clip;
 272                         goto got_clip;
 273                 }
 274
 275                 {
 276                         unique_lock<mutex> lock(queue_state_mu);
 277                         playing = false;
 278                 }
 279                 if (done_callback != nullptr) {
 280                         done_callback();
 281                 }
 282         }
 283 }
 284
 285 // Find the frame immediately before and after this point.
 286 bool Player::find_surrounding_frames(int64_t pts, int stream_idx, int64_t *pts_lower, int64_t *pts_upper)
 287 {
 288         lock_guard<mutex> lock(frame_mu);
 289
 290         // Find the first frame such that frame.pts >= pts.
 291         auto it = lower_bound(frames[stream_idx].begin(),
 292                 frames[stream_idx].end(),
 293                 pts);
 294         if (it == frames[stream_idx].end()) {
 295                 return false;
 296         }
 297         *pts_upper = *it;
 298
 299         // Find the last frame such that in_pts <= frame.pts (if any).
 300         if (it == frames[stream_idx].begin()) {
 301                 *pts_lower = *it;
 302         } else {
 303                 *pts_lower = *(it - 1);
 304         }
 305         assert(pts >= *pts_lower);
 306         assert(pts <= *pts_upper);
 307         return true;
 308 }
 309
 310 Player::Player(JPEGFrameView *destination, bool also_output_to_stream)
 311         : destination(destination)
 312 {
 313         thread(&Player::thread_func, this, also_output_to_stream).detach();
 314 }
 315
 316 void Player::play_clip(const Clip &clip, unsigned stream_idx)
 317 {
 318         {
 319                 lock_guard<mutex> lock(mu);
 320                 current_clip = clip;
 321                 current_stream_idx = stream_idx;
 322         }
 323
 324         {
 325                 lock_guard<mutex> lock(queue_state_mu);
 326                 new_clip_ready = true;
 327                 override_stream_idx = -1;
 328                 new_clip_changed.notify_all();
 329         }
 330 }
 331
 332 void Player::override_angle(unsigned stream_idx)
 333 {
 334         // Corner case: If a new clip is waiting to be played, change its stream and then we're done.
 335         {
 336                 unique_lock<mutex> lock(queue_state_mu);
 337                 if (new_clip_ready) {
 338                         lock_guard<mutex> lock2(mu);
 339                         current_stream_idx = stream_idx;
 340                         return;
 341                 }
 342         }
 343
 344         // If we are playing a clip, set override_stream_idx, and the player thread will
 345         // pick it up and change its internal index.
 346         {
 347                 unique_lock<mutex> lock(queue_state_mu);
 348                 if (playing) {
 349                         override_stream_idx = stream_idx;
 350                         new_clip_changed.notify_all();
 351                 }
 352         }
 353
 354         // OK, so we're standing still, presumably at the end of a clip.
 355         // Look at the current pts_out (if it exists), and show the closest
 356         // thing we've got.
 357         int64_t pts_out;
 358         {
 359                 lock_guard<mutex> lock(mu);
 360                 if (current_clip.pts_out < 0) {
 361                         return;
 362                 }
 363                 pts_out = current_clip.pts_out;
 364         }
 365
 366         lock_guard<mutex> lock(frame_mu);
 367         auto it = upper_bound(frames[stream_idx].begin(), frames[stream_idx].end(), pts_out);
 368         if (it == frames[stream_idx].end()) {
 369                 return;
 370         }
 371         destination->setFrame(stream_idx, *it, /*interpolated=*/false);
 372 }