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