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 got_clip:
  89                 steady_clock::time_point origin = steady_clock::now();
  90                 int64_t in_pts_origin = clip.pts_in;
  91                 int64_t out_pts_origin = pts;
  92
  93                 // Start playing exactly at a frame.
  94                 {
  95                         lock_guard<mutex> lock(frame_mu);
  96
  97                         // Find the first frame such that frame.pts <= in_pts.
  98                         auto it = lower_bound(frames[stream_idx].begin(),
  99                                 frames[stream_idx].end(),
 100                                 in_pts_origin);
 101                         if (it != frames[stream_idx].end()) {
 102                                 in_pts_origin = *it;
 103                         }
 104                 }
 105
 106                 // TODO: Lock to a rational multiple of the frame rate if possible.
 107                 double speed = 0.5;
 108
 109                 for (int frameno = 0; ; ++frameno) {  // Ends when the clip ends.
 110                         double out_pts = out_pts_origin + TIMEBASE * frameno / output_framerate;
 111                         steady_clock::time_point next_frame_start =
 112                                 origin + microseconds(lrint((out_pts - out_pts_origin) * 1e6 / TIMEBASE));
 113                         int64_t in_pts = lrint(in_pts_origin + TIMEBASE * frameno * speed / output_framerate);
 114                         pts = lrint(out_pts);
 115
 116                         steady_clock::duration time_behind = steady_clock::now() - next_frame_start;
 117                         if (time_behind >= milliseconds(200)) {
 118                                 fprintf(stderr, "WARNING: %ld ms behind, dropping a frame (no matter the type).\n",
 119                                         lrint(1e3 * duration<double>(time_behind).count()));
 120                                 continue;
 121                         }
 122
 123                         double time_left_this_clip = double(clip.pts_out - in_pts) / TIMEBASE / speed;
 124                         if (!got_next_clip && next_clip_callback != nullptr && time_left_this_clip <= clip.fade_time_seconds) {
 125                                 // Find the next clip so that we can begin a fade.
 126                                 next_clip = next_clip_callback();
 127                                 if (next_clip.pts_in != -1) {
 128                                         got_next_clip = true;
 129
 130                                         double duration_next_clip = (next_clip.pts_out - next_clip.pts_in) / TIMEBASE / speed;
 131                                         next_clip_fade_time = std::min(time_left_this_clip, duration_next_clip);
 132                                 }
 133                         }
 134
 135                         int primary_stream_idx = stream_idx;
 136                         int secondary_stream_idx = -1;
 137                         float fade_alpha = 0.0f;
 138                         if (got_next_clip) {
 139                                 secondary_stream_idx = next_clip.stream_idx;
 140                                 fade_alpha = 1.0f - time_left_this_clip / next_clip_fade_time;
 141
 142                                 // If more than half-way through the fade, interpolate the next clip
 143                                 // instead of the current one, since it's more visible.
 144                                 if (fade_alpha >= 0.5f) {
 145                                         swap(primary_stream_idx, secondary_stream_idx);
 146                                         fade_alpha = 1.0f - fade_alpha;
 147                                 }
 148                         }
 149
 150                         int64_t secondary_pts = -1;
 151                         if (got_next_clip) {
 152                                 int64_t in_pts_lower, in_pts_upper;
 153                                 bool ok = find_surrounding_frames(in_pts, secondary_stream_idx, &in_pts_lower, &in_pts_upper);
 154                                 if (ok) {
 155                                         secondary_pts = in_pts_lower;
 156                                 } else {
 157                                         secondary_stream_idx = -1;
 158                                 }
 159                         }
 160
 161                         if (progress_callback != nullptr) {
 162                                 // NOTE: None of this will take into account any snapping done below.
 163                                 double played_this_clip = double(in_pts - clip.pts_in) / TIMEBASE / speed;
 164                                 double total_length = double(clip.pts_out - clip.pts_in) / TIMEBASE / speed;
 165                                 progress_callback(played_this_clip, total_length);
 166                         }
 167
 168                         int64_t in_pts_lower, in_pts_upper;
 169                         bool ok = find_surrounding_frames(in_pts, primary_stream_idx, &in_pts_lower, &in_pts_upper);
 170                         if (!ok || in_pts_upper >= clip.pts_out) {
 171                                 break;
 172                         }
 173
 174                         // Sleep until the next frame start, or until there's a new clip we're supposed to play.
 175                         {
 176                                 unique_lock<mutex> lock(queue_state_mu);
 177                                 new_clip_changed.wait_until(lock, next_frame_start, [this]{
 178                                         return new_clip_ready || override_stream_idx != -1;
 179                                 });
 180                                 if (new_clip_ready) break;
 181                                 if (override_stream_idx != -1) {
 182                                         stream_idx = override_stream_idx;
 183                                         override_stream_idx = -1;
 184                                         continue;
 185                                 }
 186                         }
 187
 188                         if (in_pts_lower == in_pts_upper) {
 189                                 destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 190                                 if (video_stream != nullptr) {
 191                                         if (secondary_stream_idx == -1) {
 192                                                 video_stream->schedule_original_frame(pts, primary_stream_idx, in_pts_lower);
 193                                         } else {
 194                                                 video_stream->schedule_faded_frame(pts, primary_stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha);
 195                                         }
 196                                 }
 197                                 continue;
 198                         }
 199
 200                         // Snap to input frame: If we can do so with less than 1% jitter
 201                         // (ie., move less than 1% of an _output_ frame), do so.
 202                         bool snapped = false;
 203                         for (int64_t snap_pts : { in_pts_lower, in_pts_upper }) {
 204                                 double snap_pts_as_frameno = (snap_pts - in_pts_origin) * output_framerate / TIMEBASE / speed;
 205                                 if (fabs(snap_pts_as_frameno - frameno) < 0.01) {
 206                                         destination->setFrame(primary_stream_idx, snap_pts, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 207                                         if (video_stream != nullptr) {
 208                                                 if (secondary_stream_idx == -1) {
 209                                                         video_stream->schedule_original_frame(pts, primary_stream_idx, snap_pts);
 210                                                 } else {
 211                                                         video_stream->schedule_faded_frame(pts, primary_stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha);
 212                                                 }
 213                                         }
 214                                         in_pts_origin += snap_pts - in_pts;
 215                                         snapped = true;
 216                                         break;
 217                                 }
 218                         }
 219                         if (snapped) {
 220                                 continue;
 221                         }
 222
 223                         if (time_behind >= milliseconds(100)) {
 224                                 fprintf(stderr, "WARNING: %ld ms behind, dropping an interpolated frame.\n",
 225                                         lrint(1e3 * duration<double>(time_behind).count()));
 226                                 continue;
 227                         }
 228
 229                         double alpha = double(in_pts - in_pts_lower) / (in_pts_upper - in_pts_lower);
 230
 231                         if (video_stream == nullptr) {
 232                                 // Previews don't do any interpolation.
 233                                 assert(secondary_stream_idx == -1);
 234                                 destination->setFrame(primary_stream_idx, in_pts_lower, /*interpolated=*/false);
 235                         } else {
 236                                 // Calculate the interpolated frame. When it's done, the destination
 237                                 // will be unblocked.
 238                                 destination->setFrame(primary_stream_idx, pts, /*interpolated=*/true, secondary_stream_idx, secondary_pts, fade_alpha);
 239                                 video_stream->schedule_interpolated_frame(pts, primary_stream_idx, in_pts_lower, in_pts_upper, alpha, secondary_stream_idx, secondary_pts, fade_alpha);
 240                         }
 241                 }
 242
 243                 // The clip ended.
 244
 245                 // Last-ditch effort to get the next clip (if e.g. the fade time was zero seconds).
 246                 if (!got_next_clip && next_clip_callback != nullptr) {
 247                         next_clip = next_clip_callback();
 248                         if (next_clip.pts_in != -1) {
 249                                 got_next_clip = true;
 250                         }
 251                 }
 252
 253                 // Switch to next clip if we got it.
 254                 if (got_next_clip) {
 255                         clip = next_clip;
 256                         stream_idx = next_clip.stream_idx;  // Override is used for previews only, and next_clip is used for live ony.
 257                         if (done_callback != nullptr) {
 258                                 done_callback();
 259                         }
 260                         got_next_clip = false;
 261                         goto got_clip;
 262                 }
 263
 264                 {
 265                         unique_lock<mutex> lock(queue_state_mu);
 266                         playing = false;
 267                 }
 268                 if (done_callback != nullptr) {
 269                         done_callback();
 270                 }
 271         }
 272 }
 273
 274 // Find the frame immediately before and after this point.
 275 bool Player::find_surrounding_frames(int64_t pts, int stream_idx, int64_t *pts_lower, int64_t *pts_upper)
 276 {
 277         lock_guard<mutex> lock(frame_mu);
 278
 279         // Find the first frame such that frame.pts >= pts.
 280         auto it = lower_bound(frames[stream_idx].begin(),
 281                 frames[stream_idx].end(),
 282                 pts);
 283         if (it == frames[stream_idx].end()) {
 284                 return false;
 285         }
 286         *pts_upper = *it;
 287
 288         // Find the last frame such that in_pts <= frame.pts (if any).
 289         if (it == frames[stream_idx].begin()) {
 290                 *pts_lower = *it;
 291         } else {
 292                 *pts_lower = *(it - 1);
 293         }
 294         assert(pts >= *pts_lower);
 295         assert(pts <= *pts_upper);
 296         return true;
 297 }
 298
 299 Player::Player(JPEGFrameView *destination, bool also_output_to_stream)
 300         : destination(destination)
 301 {
 302         thread(&Player::thread_func, this, also_output_to_stream).detach();
 303 }
 304
 305 void Player::play_clip(const Clip &clip, unsigned stream_idx)
 306 {
 307         {
 308                 lock_guard<mutex> lock(mu);
 309                 current_clip = clip;
 310                 current_stream_idx = stream_idx;
 311         }
 312
 313         {
 314                 lock_guard<mutex> lock(queue_state_mu);
 315                 new_clip_ready = true;
 316                 override_stream_idx = -1;
 317                 new_clip_changed.notify_all();
 318         }
 319 }
 320
 321 void Player::override_angle(unsigned stream_idx)
 322 {
 323         // Corner case: If a new clip is waiting to be played, change its stream and then we're done.
 324         {
 325                 unique_lock<mutex> lock(queue_state_mu);
 326                 if (new_clip_ready) {
 327                         lock_guard<mutex> lock2(mu);
 328                         current_stream_idx = stream_idx;
 329                         return;
 330                 }
 331         }
 332
 333         // If we are playing a clip, set override_stream_idx, and the player thread will
 334         // pick it up and change its internal index.
 335         {
 336                 unique_lock<mutex> lock(queue_state_mu);
 337                 if (playing) {
 338                         override_stream_idx = stream_idx;
 339                         new_clip_changed.notify_all();
 340                 }
 341         }
 342
 343         // OK, so we're standing still, presumably at the end of a clip.
 344         // Look at the current pts_out (if it exists), and show the closest
 345         // thing we've got.
 346         int64_t pts_out;
 347         {
 348                 lock_guard<mutex> lock(mu);
 349                 if (current_clip.pts_out < 0) {
 350                         return;
 351                 }
 352                 pts_out = current_clip.pts_out;
 353         }
 354
 355         lock_guard<mutex> lock(frame_mu);
 356         auto it = upper_bound(frames[stream_idx].begin(), frames[stream_idx].end(), pts_out);
 357         if (it == frames[stream_idx].end()) {
 358                 return;
 359         }
 360         destination->setFrame(stream_idx, *it, /*interpolated=*/false);
 361 }