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                         int64_t in_pts_lower, in_pts_upper;
 101
 102                         // Find the frame immediately before and after this point.
 103                         {
 104                                 lock_guard<mutex> lock(frame_mu);
 105
 106                                 // Find the first frame such that in_pts >= frame.pts.
 107                                 auto it = lower_bound(frames[stream_idx].begin(),
 108                                         frames[stream_idx].end(),
 109                                         in_pts);
 110                                 if (it == frames[stream_idx].end() || *it >= clip.pts_out) {
 111                                         break;
 112                                 }
 113                                 in_pts_upper = *it;
 114
 115                                 // Find the last frame such that in_pts <= frame.pts (if any).
 116                                 if (it == frames[stream_idx].begin()) {
 117                                         in_pts_lower = *it;
 118                                 } else {
 119                                         in_pts_lower = *(it - 1);
 120                                 }
 121                         }
 122                         assert(in_pts >= in_pts_lower);
 123                         assert(in_pts <= in_pts_upper);
 124
 125                         // Sleep until the next frame start, or until there's a new clip we're supposed to play.
 126                         {
 127                                 unique_lock<mutex> lock(queue_state_mu);
 128                                 new_clip_changed.wait_until(lock, next_frame_start, [this]{
 129                                         return new_clip_ready || override_stream_idx != -1;
 130                                 });
 131                                 if (new_clip_ready) break;
 132                                 if (override_stream_idx != -1) {
 133                                         stream_idx = override_stream_idx;
 134                                         override_stream_idx = -1;
 135                                         continue;
 136                                 }
 137                         }
 138
 139                         if (in_pts_lower == in_pts_upper) {
 140                                 destination->setFrame(stream_idx, in_pts_lower);
 141                                 if (video_stream != nullptr) {
 142                                         video_stream->schedule_original_frame(lrint(out_pts), stream_idx, in_pts_lower);
 143                                 }
 144                                 continue;
 145                         }
 146
 147                         // Snap to input frame: If we can do so with less than 1% jitter
 148                         // (ie., move less than 1% of an _output_ frame), do so.
 149                         double in_pts_lower_as_frameno = (in_pts_lower - in_pts_origin) * output_framerate / TIMEBASE / speed;
 150                         double in_pts_upper_as_frameno = (in_pts_upper - in_pts_origin) * output_framerate / TIMEBASE / speed;
 151                         if (fabs(in_pts_lower_as_frameno - frameno) < 0.01) {
 152                                 destination->setFrame(stream_idx, in_pts_lower);
 153                                 if (video_stream != nullptr) {
 154                                         video_stream->schedule_original_frame(lrint(out_pts), stream_idx, in_pts_lower);
 155                                 }
 156                                 in_pts_origin += in_pts_lower - in_pts;
 157                                 continue;
 158                         } else if (fabs(in_pts_upper_as_frameno - frameno) < 0.01) {
 159                                 destination->setFrame(stream_idx, in_pts_upper);
 160                                 if (video_stream != nullptr) {
 161                                         video_stream->schedule_original_frame(lrint(out_pts), stream_idx, in_pts_upper);
 162                                 }
 163                                 in_pts_origin += in_pts_upper - in_pts;
 164                                 continue;
 165                         }
 166
 167                         double alpha = double(in_pts - in_pts_lower) / (in_pts_upper - in_pts_lower);
 168                         destination->setFrame(stream_idx, in_pts_lower);  // FIXME
 169
 170                         if (video_stream != nullptr) {
 171                                 // Send the frame to the stream.
 172                                 video_stream->schedule_interpolated_frame(lrint(out_pts), stream_idx, in_pts_lower, in_pts_upper, alpha);
 173                         }
 174                 }
 175
 176                 {
 177                         unique_lock<mutex> lock(queue_state_mu);
 178                         playing = false;
 179                 }
 180                 if (done_callback != nullptr && !aborted) {
 181                         done_callback();
 182                 }
 183         }
 184 }
 185
 186 Player::Player(JPEGFrameView *destination, bool also_output_to_stream)
 187         : destination(destination)
 188 {
 189         thread(&Player::thread_func, this, also_output_to_stream).detach();
 190 }
 191
 192 void Player::play_clip(const Clip &clip, unsigned stream_idx)
 193 {
 194         {
 195                 lock_guard<mutex> lock(mu);
 196                 current_clip = clip;
 197                 current_stream_idx = stream_idx;
 198         }
 199
 200         {
 201                 lock_guard<mutex> lock(queue_state_mu);
 202                 new_clip_ready = true;
 203                 override_stream_idx = -1;
 204                 new_clip_changed.notify_all();
 205         }
 206 }
 207
 208 void Player::override_angle(unsigned stream_idx)
 209 {
 210         // Corner case: If a new clip is waiting to be played, change its stream and then we're done.
 211         {
 212                 unique_lock<mutex> lock(queue_state_mu);
 213                 if (new_clip_ready) {
 214                         lock_guard<mutex> lock2(mu);
 215                         current_stream_idx = stream_idx;
 216                         return;
 217                 }
 218         }
 219
 220         // If we are playing a clip, set override_stream_idx, and the player thread will
 221         // pick it up and change its internal index.
 222         {
 223                 unique_lock<mutex> lock(queue_state_mu);
 224                 if (playing) {
 225                         override_stream_idx = stream_idx;
 226                         new_clip_changed.notify_all();
 227                 }
 228         }
 229
 230         // OK, so we're standing still, presumably at the end of a clip.
 231         // Look at the current pts_out (if it exists), and show the closest
 232         // thing we've got.
 233         int64_t pts_out;
 234         {
 235                 lock_guard<mutex> lock(mu);
 236                 if (current_clip.pts_out < 0) {
 237                         return;
 238                 }
 239                 pts_out = current_clip.pts_out;
 240         }
 241
 242         lock_guard<mutex> lock(frame_mu);
 243         auto it = upper_bound(frames[stream_idx].begin(), frames[stream_idx].end(), pts_out);
 244         if (it == frames[stream_idx].end()) {
 245                 return;
 246         }
 247         destination->setFrame(stream_idx, *it);
 248 }