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
  54         for ( ;; ) {
  55                 // Wait until we're supposed to play something.
  56                 {
  57                         unique_lock<mutex> lock(queue_state_mu);
  58                         new_clip_changed.wait(lock, [this]{
  59                                 return new_clip_ready && current_clip.pts_in != -1;
  60                         });
  61                         new_clip_ready = false;
  62                         playing = true;
  63                 }
  64
  65                 Clip clip;
  66                 unsigned stream_idx;
  67                 {
  68                         lock_guard<mutex> lock(mu);
  69                         clip = current_clip;
  70                         stream_idx = current_stream_idx;
  71                 }
  72                 steady_clock::time_point origin = steady_clock::now();
  73                 int64_t in_pts_origin = clip.pts_in;
  74                 int64_t out_pts_origin = pts;
  75
  76                 // Start playing exactly at a frame.
  77                 {
  78                         lock_guard<mutex> lock(frame_mu);
  79
  80                         // Find the first frame such that frame.pts <= in_pts.
  81                         auto it = lower_bound(frames[stream_idx].begin(),
  82                                 frames[stream_idx].end(),
  83                                 in_pts_origin);
  84                         if (it != frames[stream_idx].end()) {
  85                                 in_pts_origin = *it;
  86                         }
  87                 }
  88
  89                 // TODO: Lock to a rational multiple of the frame rate if possible.
  90                 double speed = 0.5;
  91
  92                 bool aborted = false;
  93                 for (int frameno = 0; ; ++frameno) {  // Ends when the clip ends.
  94                         double out_pts = out_pts_origin + TIMEBASE * frameno / output_framerate;
  95                         steady_clock::time_point next_frame_start =
  96                                 origin + microseconds(lrint((out_pts - out_pts_origin) * 1e6 / TIMEBASE));
  97                         int64_t in_pts = lrint(in_pts_origin + TIMEBASE * frameno * speed / output_framerate);
  98                         pts = lrint(out_pts);
  99
 100                         steady_clock::duration time_behind = steady_clock::now() - next_frame_start;
 101                         if (time_behind >= milliseconds(200)) {
 102                                 fprintf(stderr, "WARNING: %ld ms behind, dropping a frame (no matter the type).\n",
 103                                         lrint(1e3 * duration<double>(time_behind).count()));
 104                                 continue;
 105                         }
 106
 107                         int64_t in_pts_lower, in_pts_upper;
 108                         bool ok = find_surrounding_frames(in_pts, stream_idx, &in_pts_lower, &in_pts_upper);
 109                         if (!ok || in_pts_upper >= clip.pts_out) {
 110                                 break;
 111                         }
 112
 113                         // Sleep until the next frame start, or until there's a new clip we're supposed to play.
 114                         {
 115                                 unique_lock<mutex> lock(queue_state_mu);
 116                                 new_clip_changed.wait_until(lock, next_frame_start, [this]{
 117                                         return new_clip_ready || override_stream_idx != -1;
 118                                 });
 119                                 if (new_clip_ready) break;
 120                                 if (override_stream_idx != -1) {
 121                                         stream_idx = override_stream_idx;
 122                                         override_stream_idx = -1;
 123                                         continue;
 124                                 }
 125                         }
 126
 127                         if (progress_callback != nullptr) {
 128                                 // NOTE: None of this will take into account any snapping done below.
 129                                 double played_this_clip = double(in_pts - clip.pts_in) / TIMEBASE / speed;
 130                                 double total_length = double(clip.pts_out - clip.pts_in) / TIMEBASE / speed;
 131                                 progress_callback(played_this_clip, total_length);
 132                         }
 133
 134                         if (in_pts_lower == in_pts_upper) {
 135                                 destination->setFrame(stream_idx, in_pts_lower, /*interpolated=*/false);
 136                                 if (video_stream != nullptr) {
 137                                         video_stream->schedule_original_frame(lrint(out_pts), stream_idx, in_pts_lower);
 138                                 }
 139                                 continue;
 140                         }
 141
 142                         // Snap to input frame: If we can do so with less than 1% jitter
 143                         // (ie., move less than 1% of an _output_ frame), do so.
 144                         bool snapped = false;
 145                         for (int64_t snap_pts : { in_pts_lower, in_pts_upper }) {
 146                                 double snap_pts_as_frameno = (snap_pts - in_pts_origin) * output_framerate / TIMEBASE / speed;
 147                                 if (fabs(snap_pts_as_frameno - frameno) < 0.01) {
 148                                         destination->setFrame(stream_idx, snap_pts, /*interpolated=*/false);
 149                                         if (video_stream != nullptr) {
 150                                                 video_stream->schedule_original_frame(lrint(out_pts), stream_idx, snap_pts);
 151                                         }
 152                                         in_pts_origin += snap_pts - in_pts;
 153                                         snapped = true;
 154                                         break;
 155                                 }
 156                         }
 157                         if (snapped) {
 158                                 continue;
 159                         }
 160
 161                         if (time_behind >= milliseconds(100)) {
 162                                 fprintf(stderr, "WARNING: %ld ms behind, dropping an interpolated frame.\n",
 163                                         lrint(1e3 * duration<double>(time_behind).count()));
 164                                 continue;
 165                         }
 166
 167                         double alpha = double(in_pts - in_pts_lower) / (in_pts_upper - in_pts_lower);
 168
 169                         if (video_stream == nullptr) {
 170                                 // Previews don't do any interpolation.
 171                                 destination->setFrame(stream_idx, in_pts_lower, /*interpolated=*/false);
 172                         } else {
 173                                 // Calculate the interpolated frame. When it's done, the destination
 174                                 // will be unblocked.
 175                                 destination->setFrame(stream_idx, lrint(out_pts), /*interpolated=*/true);
 176                                 video_stream->schedule_interpolated_frame(lrint(out_pts), stream_idx, in_pts_lower, in_pts_upper, alpha);
 177                         }
 178                 }
 179
 180                 {
 181                         unique_lock<mutex> lock(queue_state_mu);
 182                         playing = false;
 183                 }
 184                 if (done_callback != nullptr && !aborted) {
 185                         done_callback();
 186                 }
 187         }
 188 }
 189
 190 // Find the frame immediately before and after this point.
 191 bool Player::find_surrounding_frames(int64_t pts, int stream_idx, int64_t *pts_lower, int64_t *pts_upper)
 192 {
 193         lock_guard<mutex> lock(frame_mu);
 194
 195         // Find the first frame such that frame.pts >= pts.
 196         auto it = lower_bound(frames[stream_idx].begin(),
 197                 frames[stream_idx].end(),
 198                 pts);
 199         if (it == frames[stream_idx].end()) {
 200                 return false;
 201         }
 202         *pts_upper = *it;
 203
 204         // Find the last frame such that in_pts <= frame.pts (if any).
 205         if (it == frames[stream_idx].begin()) {
 206                 *pts_lower = *it;
 207         } else {
 208                 *pts_lower = *(it - 1);
 209         }
 210         assert(pts >= *pts_lower);
 211         assert(pts <= *pts_upper);
 212         return true;
 213 }
 214
 215 Player::Player(JPEGFrameView *destination, bool also_output_to_stream)
 216         : destination(destination)
 217 {
 218         thread(&Player::thread_func, this, also_output_to_stream).detach();
 219 }
 220
 221 void Player::play_clip(const Clip &clip, unsigned stream_idx)
 222 {
 223         {
 224                 lock_guard<mutex> lock(mu);
 225                 current_clip = clip;
 226                 current_stream_idx = stream_idx;
 227         }
 228
 229         {
 230                 lock_guard<mutex> lock(queue_state_mu);
 231                 new_clip_ready = true;
 232                 override_stream_idx = -1;
 233                 new_clip_changed.notify_all();
 234         }
 235 }
 236
 237 void Player::override_angle(unsigned stream_idx)
 238 {
 239         // Corner case: If a new clip is waiting to be played, change its stream and then we're done.
 240         {
 241                 unique_lock<mutex> lock(queue_state_mu);
 242                 if (new_clip_ready) {
 243                         lock_guard<mutex> lock2(mu);
 244                         current_stream_idx = stream_idx;
 245                         return;
 246                 }
 247         }
 248
 249         // If we are playing a clip, set override_stream_idx, and the player thread will
 250         // pick it up and change its internal index.
 251         {
 252                 unique_lock<mutex> lock(queue_state_mu);
 253                 if (playing) {
 254                         override_stream_idx = stream_idx;
 255                         new_clip_changed.notify_all();
 256                 }
 257         }
 258
 259         // OK, so we're standing still, presumably at the end of a clip.
 260         // Look at the current pts_out (if it exists), and show the closest
 261         // thing we've got.
 262         int64_t pts_out;
 263         {
 264                 lock_guard<mutex> lock(mu);
 265                 if (current_clip.pts_out < 0) {
 266                         return;
 267                 }
 268                 pts_out = current_clip.pts_out;
 269         }
 270
 271         lock_guard<mutex> lock(frame_mu);
 272         auto it = upper_bound(frames[stream_idx].begin(), frames[stream_idx].end(), pts_out);
 273         if (it == frames[stream_idx].end()) {
 274                 return;
 275         }
 276         destination->setFrame(stream_idx, *it, /*interpolated=*/false);
 277 }