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                 // Wait until we're supposed to play something.
  59                 {
  60                         unique_lock<mutex> lock(queue_state_mu);
  61                         new_clip_changed.wait(lock, [this]{
  62                                 return new_clip_ready && current_clip.pts_in != -1;
  63                         });
  64                         new_clip_ready = false;
  65                         playing = true;
  66                 }
  67
  68                 Clip clip;
  69                 unsigned stream_idx;
  70                 {
  71                         lock_guard<mutex> lock(mu);
  72                         clip = current_clip;
  73                         stream_idx = current_stream_idx;
  74                 }
  75 got_clip:
  76                 steady_clock::time_point origin = steady_clock::now();
  77                 int64_t in_pts_origin = clip.pts_in;
  78                 int64_t out_pts_origin = pts;
  79
  80                 // Start playing exactly at a frame.
  81                 {
  82                         lock_guard<mutex> lock(frame_mu);
  83
  84                         // Find the first frame such that frame.pts <= in_pts.
  85                         auto it = lower_bound(frames[stream_idx].begin(),
  86                                 frames[stream_idx].end(),
  87                                 in_pts_origin);
  88                         if (it != frames[stream_idx].end()) {
  89                                 in_pts_origin = *it;
  90                         }
  91                 }
  92
  93                 // TODO: Lock to a rational multiple of the frame rate if possible.
  94                 double speed = 0.5;
  95
  96                 for (int frameno = 0; ; ++frameno) {  // Ends when the clip ends.
  97                         double out_pts = out_pts_origin + TIMEBASE * frameno / output_framerate;
  98                         steady_clock::time_point next_frame_start =
  99                                 origin + microseconds(lrint((out_pts - out_pts_origin) * 1e6 / TIMEBASE));
 100                         int64_t in_pts = lrint(in_pts_origin + TIMEBASE * frameno * speed / output_framerate);
 101                         pts = lrint(out_pts);
 102
 103                         steady_clock::duration time_behind = steady_clock::now() - next_frame_start;
 104                         if (time_behind >= milliseconds(200)) {
 105                                 fprintf(stderr, "WARNING: %ld ms behind, dropping a frame (no matter the type).\n",
 106                                         lrint(1e3 * duration<double>(time_behind).count()));
 107                                 continue;
 108                         }
 109
 110                         double time_left_this_clip = double(clip.pts_out - in_pts) / TIMEBASE / speed;
 111                         if (!got_next_clip && next_clip_callback != nullptr && time_left_this_clip <= clip.fade_time_seconds) {
 112                                 // Find the next clip so that we can begin a fade.
 113                                 next_clip = next_clip_callback();
 114                                 if (next_clip.pts_in != -1) {
 115                                         got_next_clip = true;
 116
 117                                         double duration_next_clip = (next_clip.pts_out - next_clip.pts_in) / TIMEBASE / speed;
 118                                         next_clip_fade_time = std::min(time_left_this_clip, duration_next_clip);
 119                                         fprintf(stderr, "decided on %.3f seconds fade time [%f %f]\n", next_clip_fade_time, time_left_this_clip, duration_next_clip);
 120                                 }
 121                         }
 122
 123                         // TODO: If more than half-way through the fade, interpolate the next clip
 124                         // instead of the current one.
 125
 126                         int secondary_stream_idx = -1;
 127                         int64_t secondary_pts = -1;
 128                         float fade_alpha = 0.0f;
 129                         if (got_next_clip) {
 130                                 int64_t in_pts_lower, in_pts_upper;
 131                                 bool ok = find_surrounding_frames(in_pts, next_clip.stream_idx, &in_pts_lower, &in_pts_upper);
 132                                 if (ok) {
 133                                         secondary_stream_idx = next_clip.stream_idx;
 134                                         secondary_pts = in_pts_lower;
 135                                         fade_alpha = 1.0f - time_left_this_clip / next_clip_fade_time;
 136                                 }
 137                         }
 138
 139                         if (progress_callback != nullptr) {
 140                                 // NOTE: None of this will take into account any snapping done below.
 141                                 double played_this_clip = double(in_pts - clip.pts_in) / TIMEBASE / speed;
 142                                 double total_length = double(clip.pts_out - clip.pts_in) / TIMEBASE / speed;
 143                                 progress_callback(played_this_clip, total_length);
 144                         }
 145
 146                         int64_t in_pts_lower, in_pts_upper;
 147                         bool ok = find_surrounding_frames(in_pts, stream_idx, &in_pts_lower, &in_pts_upper);
 148                         if (!ok || in_pts_upper >= clip.pts_out) {
 149                                 break;
 150                         }
 151
 152                         // Sleep until the next frame start, or until there's a new clip we're supposed to play.
 153                         {
 154                                 unique_lock<mutex> lock(queue_state_mu);
 155                                 new_clip_changed.wait_until(lock, next_frame_start, [this]{
 156                                         return new_clip_ready || override_stream_idx != -1;
 157                                 });
 158                                 if (new_clip_ready) break;
 159                                 if (override_stream_idx != -1) {
 160                                         stream_idx = override_stream_idx;
 161                                         override_stream_idx = -1;
 162                                         continue;
 163                                 }
 164                         }
 165
 166                         if (in_pts_lower == in_pts_upper) {
 167                                 destination->setFrame(stream_idx, in_pts_lower, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 168                                 if (video_stream != nullptr) {
 169                                         if (secondary_stream_idx == -1) {
 170                                                 video_stream->schedule_original_frame(pts, stream_idx, in_pts_lower);
 171                                         } else {
 172                                                 video_stream->schedule_faded_frame(pts, stream_idx, in_pts_lower, secondary_stream_idx, secondary_pts, fade_alpha);
 173                                         }
 174                                 }
 175                                 continue;
 176                         }
 177
 178                         // Snap to input frame: If we can do so with less than 1% jitter
 179                         // (ie., move less than 1% of an _output_ frame), do so.
 180                         bool snapped = false;
 181                         for (int64_t snap_pts : { in_pts_lower, in_pts_upper }) {
 182                                 double snap_pts_as_frameno = (snap_pts - in_pts_origin) * output_framerate / TIMEBASE / speed;
 183                                 if (fabs(snap_pts_as_frameno - frameno) < 0.01) {
 184                                         destination->setFrame(stream_idx, snap_pts, /*interpolated=*/false, secondary_stream_idx, secondary_pts, fade_alpha);
 185                                         if (video_stream != nullptr) {
 186                                                 if (secondary_stream_idx == -1) {
 187                                                         video_stream->schedule_original_frame(pts, stream_idx, snap_pts);
 188                                                 } else {
 189                                                         video_stream->schedule_faded_frame(pts, stream_idx, snap_pts, secondary_stream_idx, secondary_pts, fade_alpha);
 190                                                 }
 191                                         }
 192                                         in_pts_origin += snap_pts - in_pts;
 193                                         snapped = true;
 194                                         break;
 195                                 }
 196                         }
 197                         if (snapped) {
 198                                 continue;
 199                         }
 200
 201                         if (time_behind >= milliseconds(100)) {
 202                                 fprintf(stderr, "WARNING: %ld ms behind, dropping an interpolated frame.\n",
 203                                         lrint(1e3 * duration<double>(time_behind).count()));
 204                                 continue;
 205                         }
 206
 207                         double alpha = double(in_pts - in_pts_lower) / (in_pts_upper - in_pts_lower);
 208
 209                         if (video_stream == nullptr) {
 210                                 // Previews don't do any interpolation.
 211                                 assert(secondary_stream_idx == -1);
 212                                 destination->setFrame(stream_idx, in_pts_lower, /*interpolated=*/false, fade_alpha);
 213                         } else {
 214                                 // Calculate the interpolated frame. When it's done, the destination
 215                                 // will be unblocked.
 216                                 destination->setFrame(stream_idx, pts, /*interpolated=*/true, secondary_stream_idx, secondary_pts, fade_alpha);
 217                                 video_stream->schedule_interpolated_frame(pts, stream_idx, in_pts_lower, in_pts_upper, alpha, secondary_stream_idx, secondary_pts, fade_alpha);
 218                         }
 219                 }
 220
 221                 // The clip ended.
 222
 223                 // Last-ditch effort to get the next clip (if e.g. the fade time was zero seconds).
 224                 if (!got_next_clip && next_clip_callback != nullptr) {
 225                         next_clip = next_clip_callback();
 226                         if (next_clip.pts_in != -1) {
 227                                 got_next_clip = true;
 228                         }
 229                 }
 230
 231                 // Switch to next clip if we got it.
 232                 if (got_next_clip) {
 233                         clip = next_clip;
 234                         stream_idx = next_clip.stream_idx;  // Override is used for previews only, and next_clip is used for live ony.
 235                         if (done_callback != nullptr) {
 236                                 done_callback();
 237                         }
 238                         got_next_clip = false;
 239                         goto got_clip;
 240                 }
 241
 242                 {
 243                         unique_lock<mutex> lock(queue_state_mu);
 244                         playing = false;
 245                 }
 246                 if (done_callback != nullptr) {
 247                         done_callback();
 248                 }
 249         }
 250 }
 251
 252 // Find the frame immediately before and after this point.
 253 bool Player::find_surrounding_frames(int64_t pts, int stream_idx, int64_t *pts_lower, int64_t *pts_upper)
 254 {
 255         lock_guard<mutex> lock(frame_mu);
 256
 257         // Find the first frame such that frame.pts >= pts.
 258         auto it = lower_bound(frames[stream_idx].begin(),
 259                 frames[stream_idx].end(),
 260                 pts);
 261         if (it == frames[stream_idx].end()) {
 262                 return false;
 263         }
 264         *pts_upper = *it;
 265
 266         // Find the last frame such that in_pts <= frame.pts (if any).
 267         if (it == frames[stream_idx].begin()) {
 268                 *pts_lower = *it;
 269         } else {
 270                 *pts_lower = *(it - 1);
 271         }
 272         assert(pts >= *pts_lower);
 273         assert(pts <= *pts_upper);
 274         return true;
 275 }
 276
 277 Player::Player(JPEGFrameView *destination, bool also_output_to_stream)
 278         : destination(destination)
 279 {
 280         thread(&Player::thread_func, this, also_output_to_stream).detach();
 281 }
 282
 283 void Player::play_clip(const Clip &clip, unsigned stream_idx)
 284 {
 285         {
 286                 lock_guard<mutex> lock(mu);
 287                 current_clip = clip;
 288                 current_stream_idx = stream_idx;
 289         }
 290
 291         {
 292                 lock_guard<mutex> lock(queue_state_mu);
 293                 new_clip_ready = true;
 294                 override_stream_idx = -1;
 295                 new_clip_changed.notify_all();
 296         }
 297 }
 298
 299 void Player::override_angle(unsigned stream_idx)
 300 {
 301         // Corner case: If a new clip is waiting to be played, change its stream and then we're done.
 302         {
 303                 unique_lock<mutex> lock(queue_state_mu);
 304                 if (new_clip_ready) {
 305                         lock_guard<mutex> lock2(mu);
 306                         current_stream_idx = stream_idx;
 307                         return;
 308                 }
 309         }
 310
 311         // If we are playing a clip, set override_stream_idx, and the player thread will
 312         // pick it up and change its internal index.
 313         {
 314                 unique_lock<mutex> lock(queue_state_mu);
 315                 if (playing) {
 316                         override_stream_idx = stream_idx;
 317                         new_clip_changed.notify_all();
 318                 }
 319         }
 320
 321         // OK, so we're standing still, presumably at the end of a clip.
 322         // Look at the current pts_out (if it exists), and show the closest
 323         // thing we've got.
 324         int64_t pts_out;
 325         {
 326                 lock_guard<mutex> lock(mu);
 327                 if (current_clip.pts_out < 0) {
 328                         return;
 329                 }
 330                 pts_out = current_clip.pts_out;
 331         }
 332
 333         lock_guard<mutex> lock(frame_mu);
 334         auto it = upper_bound(frames[stream_idx].begin(), frames[stream_idx].end(), pts_out);
 335         if (it == frames[stream_idx].end()) {
 336                 return;
 337         }
 338         destination->setFrame(stream_idx, *it, /*interpolated=*/false);
 339 }