git.sesse.net Git - casparcg/blob - core/producer/framerate/framerate_producer.cpp

   1 /*
   2 * Copyright (c) 2011 Sveriges Television AB <info@casparcg.com>
   3 *
   4 * This file is part of CasparCG (www.casparcg.com).
   5 *
   6 * CasparCG is free software: you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation, either version 3 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * CasparCG is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with CasparCG. If not, see <http://www.gnu.org/licenses/>.
  18 *
  19 * Author: Helge Norberg, helge.norberg@svt.se
  20 */
  21
  22 #include "../../StdAfx.h"
  23
  24 #include "framerate_producer.h"
  25
  26 #include "../frame_producer.h"
  27 #include "../../frame/audio_channel_layout.h"
  28 #include "../../frame/draw_frame.h"
  29 #include "../../frame/frame.h"
  30 #include "../../frame/frame_transform.h"
  31 #include "../../frame/pixel_format.h"
  32 #include "../../monitor/monitor.h"
  33 #include "../../help/help_sink.h"
  34
  35 #include <common/future.h>
  36 #include <common/tweener.h>
  37
  38 #include <functional>
  39 #include <queue>
  40 #include <future>
  41 #include <stack>
  42
  43 namespace caspar { namespace core {
  44
  45 draw_frame drop_and_skip(const draw_frame& source, const draw_frame&, const boost::rational<int64_t>&)
  46 {
  47         return source;
  48 }
  49
  50 // Blends next frame with current frame when the distance is not 0.
  51 // Completely sharp when distance is 0 but blurry when in between.
  52 draw_frame blend(const draw_frame& source, const draw_frame& destination, const boost::rational<int64_t>& distance)
  53 {
  54         if (destination == draw_frame::empty())
  55                 return source;
  56
  57         auto under                                      = source;
  58         auto over                                       = destination;
  59         double float_distance           = boost::rational_cast<double>(distance);
  60
  61         under.transform().image_transform.is_mix        = true;
  62         under.transform().image_transform.opacity       = 1 - float_distance;
  63         over.transform().image_transform.is_mix         = true;
  64         over.transform().image_transform.opacity        = float_distance;
  65
  66         return draw_frame::over(under, over);
  67 }
  68
  69 // Blends a moving window with a width of 1 frame duration.
  70 // * A distance of 0.0 gives 50% previous, 50% current and 0% next.
  71 // * A distance of 0.5 gives 25% previous, 50% current and 25% next.
  72 // * A distance of 0.75 gives 12.5% previous, 50% current and 37.5% next.
  73 // This is blurrier than blend, but gives a more even bluriness, instead of sharp, blurry, sharp, blurry.
  74 struct blend_all
  75 {
  76         draw_frame previous_frame       = draw_frame::empty();
  77         draw_frame last_source          = draw_frame::empty();
  78         draw_frame last_destination     = draw_frame::empty();
  79
  80         draw_frame operator()(const draw_frame& source, const draw_frame& destination, const boost::rational<int64_t>& distance)
  81         {
  82                 if (last_source != draw_frame::empty() && last_source != source)
  83                 {
  84                         if (last_destination == source)
  85                                 previous_frame = last_source;
  86                         else // A two frame jump
  87                                 previous_frame = last_destination;
  88                 }
  89
  90                 last_source                     = source;
  91                 last_destination        = destination;
  92
  93                 bool has_previous = previous_frame != draw_frame::empty();
  94
  95                 if (!has_previous)
  96                         return blend(source, destination, distance);
  97
  98                 auto middle                                                                                     = last_source;
  99                 auto next_frame                                                                         = destination;
 100                 previous_frame.transform().image_transform.is_mix       = true;
 101                 middle.transform().image_transform.is_mix                       = true;
 102                 next_frame.transform().image_transform.is_mix           = true;
 103
 104                 double float_distance                                                           = boost::rational_cast<double>(distance);
 105                 previous_frame.transform().image_transform.opacity      = std::max(0.0, 0.5 - float_distance * 0.5);
 106                 middle.transform().image_transform.opacity                      = 0.5;
 107                 next_frame.transform().image_transform.opacity          = 1.0 - previous_frame.transform().image_transform.opacity - middle.transform().image_transform.opacity;
 108
 109                 std::vector<draw_frame> combination { previous_frame, middle, next_frame };
 110
 111                 return draw_frame(std::move(combination));
 112         }
 113 };
 114
 115 class audio_extractor : public frame_visitor
 116 {
 117         std::stack<core::audio_transform>                               transform_stack_;
 118         std::function<void(const const_frame& frame)>   on_frame_;
 119 public:
 120         audio_extractor(std::function<void(const const_frame& frame)> on_frame)
 121                 : on_frame_(std::move(on_frame))
 122         {
 123                 transform_stack_.push(audio_transform());
 124         }
 125
 126         void push(const frame_transform& transform) override
 127         {
 128                 transform_stack_.push(transform_stack_.top() * transform.audio_transform);
 129         }
 130
 131         void pop() override
 132         {
 133                 transform_stack_.pop();
 134         }
 135
 136         void visit(const const_frame& frame) override
 137         {
 138                 if (!frame.audio_data().empty() && !transform_stack_.top().is_still)
 139                         on_frame_(frame);
 140         }
 141 };
 142
 143 // Like tweened_transform but for framerates
 144 class speed_tweener
 145 {
 146         boost::rational<int64_t>        source_         = 1LL;
 147         boost::rational<int64_t>        dest_           = 1LL;
 148         int                                                     duration_       = 0;
 149         int                                                     time_           = 0;
 150         tweener                                         tweener_;
 151 public:
 152         speed_tweener() = default;
 153         speed_tweener(
 154                         const boost::rational<int64_t>& source,
 155                         const boost::rational<int64_t>& dest,
 156                         int duration,
 157                         const tweener& tween)
 158                 : source_(source)
 159                 , dest_(dest)
 160                 , duration_(duration)
 161                 , time_(0)
 162                 , tweener_(tween)
 163         {
 164         }
 165
 166         const boost::rational<int64_t>& dest() const
 167         {
 168                 return dest_;
 169         }
 170
 171         boost::rational<int64_t> fetch() const
 172         {
 173                 if (time_ == duration_)
 174                         return dest_;
 175
 176                 double source   = boost::rational_cast<double>(source_);
 177                 double delta    = boost::rational_cast<double>(dest_) - source;
 178                 double result   = tweener_(time_, source, delta, duration_);
 179
 180                 return boost::rational<int64_t>(static_cast<int64_t>(result * 1000000.0), 1000000);
 181         }
 182
 183         boost::rational<int64_t> fetch_and_tick()
 184         {
 185                 time_ = std::min(time_ + 1, duration_);
 186                 return fetch();
 187         }
 188 };
 189
 190 class framerate_producer : public frame_producer_base
 191 {
 192         spl::shared_ptr<frame_producer>                                         source_;
 193         boost::rational<int>                                                            source_framerate_;
 194         audio_channel_layout                                                            source_channel_layout_          = audio_channel_layout::invalid();
 195         boost::rational<int>                                                            destination_framerate_;
 196         field_mode                                                                                      destination_fieldmode_;
 197         std::vector<int>                                                                        destination_audio_cadence_;
 198         boost::rational<std::int64_t>                                           speed_;
 199         speed_tweener                                                                           user_speed_;
 200         std::function<draw_frame (
 201                         const draw_frame& source,
 202                         const draw_frame& destination,
 203                         const boost::rational<int64_t>& distance)>      interpolator_                           = drop_and_skip;
 204
 205         boost::rational<std::int64_t>                                           current_frame_number_           = 0;
 206         draw_frame                                                                                      previous_frame_                         = draw_frame::empty();
 207         draw_frame                                                                                      next_frame_                                     = draw_frame::empty();
 208         mutable_audio_buffer                                                            audio_samples_;
 209
 210         unsigned int                                                                            output_repeat_                          = 0;
 211         unsigned int                                                                            output_frame_                           = 0;
 212 public:
 213         framerate_producer(
 214                         spl::shared_ptr<frame_producer> source,
 215                         boost::rational<int> source_framerate,
 216                         boost::rational<int> destination_framerate,
 217                         field_mode destination_fieldmode,
 218                         std::vector<int> destination_audio_cadence)
 219                 : source_(std::move(source))
 220                 , source_framerate_(std::move(source_framerate))
 221                 , destination_framerate_(std::move(destination_framerate))
 222                 , destination_fieldmode_(destination_fieldmode)
 223                 , destination_audio_cadence_(std::move(destination_audio_cadence))
 224         {
 225                 // Coarse adjustment to correct fps family (23.98 - 30 vs 47.95 - 60)
 226                 if (destination_fieldmode_ != field_mode::progressive)  // Interlaced output
 227                 {
 228                         auto diff_double        = boost::abs(source_framerate_ - destination_framerate_ * 2);
 229                         auto diff_keep          = boost::abs(source_framerate_ - destination_framerate_);
 230
 231                         if (diff_double < diff_keep)                                            // Double rate interlaced
 232                         {
 233                                 destination_framerate_ *= 2;
 234                         }
 235                         else                                                                                            // Progressive non interlaced
 236                         {
 237                                 destination_fieldmode_ = field_mode::progressive;
 238                         }
 239                 }
 240                 else                                                                                                    // Progressive
 241                 {
 242                         auto diff_halve = boost::abs(source_framerate_ * 2      - destination_framerate_);
 243                         auto diff_keep  = boost::abs(source_framerate_          - destination_framerate_);
 244
 245                         if (diff_halve < diff_keep)                                                     // Repeat every frame two times
 246                         {
 247                                 destination_framerate_  /= 2;
 248                                 output_repeat_                  = 2;
 249                         }
 250                 }
 251
 252                 speed_ = boost::rational<int64_t>(source_framerate_ / destination_framerate_);
 253
 254                 // drop_and_skip will only be used by default for exact framerate multiples (half, same and double)
 255                 // for all other framerates a frame interpolator will be chosen.
 256                 if (speed_ != 1 && speed_ * 2 != 1 && speed_ != 2)
 257                 {
 258                         auto high_source_framerate              = source_framerate_ > 47;
 259                         auto high_destination_framerate = destination_framerate_ > 47
 260                                         || destination_fieldmode_ != field_mode::progressive;
 261
 262                         if (high_source_framerate && high_destination_framerate)        // The bluriness of blend_all is acceptable on high framerates.
 263                                 interpolator_ = blend_all();
 264                         else                                                                                                            // blend_all is mostly too blurry on low framerates. blend provides a compromise.
 265                                 interpolator_ = &blend;
 266
 267                         CASPAR_LOG(warning) << source_->print() << L" Frame blending frame rate conversion required to conform to channel frame rate.";
 268                 }
 269
 270                 // Note: Uses 1 step rotated cadence for 1001 modes (1602, 1602, 1601, 1602, 1601)
 271                 // This cadence fills the audio mixer most optimally.
 272                 boost::range::rotate(destination_audio_cadence_, std::end(destination_audio_cadence_) - 1);
 273         }
 274
 275         draw_frame receive_impl() override
 276         {
 277                 if (destination_fieldmode_ == field_mode::progressive)
 278                 {
 279                         return do_render_progressive_frame(true);
 280                 }
 281                 else
 282                 {
 283                         auto field1 = do_render_progressive_frame(true);
 284                         auto field2 = do_render_progressive_frame(false);
 285
 286                         return draw_frame::interlace(field1, field2, destination_fieldmode_);
 287                 }
 288         }
 289
 290         std::future<std::wstring> call(const std::vector<std::wstring>& params) override
 291         {
 292                 if (!boost::iequals(params.at(0), L"framerate"))
 293                         return source_->call(params);
 294
 295                 if (boost::iequals(params.at(1), L"speed"))
 296                 {
 297                         auto destination_user_speed = boost::rational<std::int64_t>(
 298                                         static_cast<std::int64_t>(boost::lexical_cast<double>(params.at(2)) * 1000000.0),
 299                                         1000000);
 300                         auto frames = params.size() > 3 ? boost::lexical_cast<int>(params.at(3)) : 0;
 301                         auto easing = params.size() > 4 ? params.at(4) : L"linear";
 302
 303                         user_speed_ = speed_tweener(user_speed_.fetch(), destination_user_speed, frames, tweener(easing));
 304                 }
 305                 else if (boost::iequals(params.at(1), L"interpolation"))
 306                 {
 307                         if (boost::iequals(params.at(2), L"blend"))
 308                                 interpolator_ = &blend;
 309                         else if (boost::iequals(params.at(2), L"blend_all"))
 310                                 interpolator_ = blend_all();
 311                         else
 312                                 interpolator_ = &drop_and_skip;
 313                 }
 314                 else if (boost::iequals(params.at(1), L"output_repeat")) // Only for debugging purposes
 315                 {
 316                         output_repeat_ = boost::lexical_cast<unsigned int>(params.at(2));
 317                 }
 318
 319                 return make_ready_future<std::wstring>(L"");
 320         }
 321
 322         monitor::subject& monitor_output() override
 323         {
 324                 return source_->monitor_output();
 325         }
 326
 327         std::wstring print() const override
 328         {
 329                 return source_->print();
 330         }
 331
 332         std::wstring name() const override
 333         {
 334                 return source_->name();
 335         }
 336
 337         boost::property_tree::wptree info() const override
 338         {
 339                 auto info = source_->info();
 340
 341                 auto incorrect_frame_number = info.get_child_optional(L"frame-number");
 342                 if (incorrect_frame_number)
 343                         incorrect_frame_number->put_value(frame_number());
 344
 345                 auto incorrect_nb_frames = info.get_child_optional(L"nb-frames");
 346                 if (incorrect_nb_frames)
 347                         incorrect_nb_frames->put_value(nb_frames());
 348
 349                 return info;
 350         }
 351
 352         uint32_t nb_frames() const override
 353         {
 354                 auto source_nb_frames = source_->nb_frames();
 355                 auto multiple = boost::rational_cast<double>(1 / get_speed() * (output_repeat_ != 0 ? 2 : 1));
 356
 357                 return static_cast<uint32_t>(source_nb_frames * multiple);
 358         }
 359
 360         uint32_t frame_number() const override
 361         {
 362                 auto source_frame_number = source_->frame_number() - 1; // next frame already received
 363                 auto multiple = boost::rational_cast<double>(1 / get_speed() * (output_repeat_ != 0 ? 2 : 1));
 364
 365                 return static_cast<uint32_t>(source_frame_number * multiple);
 366         }
 367
 368         constraints& pixel_constraints() override
 369         {
 370                 return source_->pixel_constraints();
 371         }
 372 private:
 373         draw_frame do_render_progressive_frame(bool sound)
 374         {
 375                 user_speed_.fetch_and_tick();
 376
 377                 if (output_repeat_ && ++output_frame_ % output_repeat_)
 378                 {
 379                         auto frame = draw_frame::still(last_frame());
 380
 381                         frame.transform().audio_transform.volume = 0.0;
 382
 383                         return attach_sound(frame);
 384                 }
 385
 386                 if (previous_frame_ == draw_frame::empty())
 387                         previous_frame_ = pop_frame_from_source();
 388
 389                 auto current_frame_number       = current_frame_number_;
 390                 auto distance                           = current_frame_number_ - boost::rational_cast<int64_t>(current_frame_number_);
 391                 bool needs_next                         = distance > 0 || !enough_sound();
 392
 393                 if (needs_next && next_frame_ == draw_frame::empty())
 394                         next_frame_ = pop_frame_from_source();
 395
 396                 auto result = interpolator_(previous_frame_, next_frame_, distance);
 397
 398                 auto next_frame_number          = current_frame_number_ += get_speed();
 399                 auto integer_current_frame      = boost::rational_cast<std::int64_t>(current_frame_number);
 400                 auto integer_next_frame         = boost::rational_cast<std::int64_t>(next_frame_number);
 401
 402                 fast_forward_integer_frames(integer_next_frame - integer_current_frame);
 403
 404                 if (sound)
 405                         return attach_sound(result);
 406                 else
 407                         return result;
 408         }
 409
 410         void fast_forward_integer_frames(std::int64_t num_frames)
 411         {
 412                 if (num_frames == 0)
 413                         return;
 414
 415                 for (std::int64_t i = 0; i < num_frames; ++i)
 416                 {
 417                         if (next_frame_ == draw_frame::empty())
 418                                 previous_frame_ = pop_frame_from_source();
 419                         else
 420                         {
 421                                 previous_frame_ = std::move(next_frame_);
 422
 423                                 next_frame_ = pop_frame_from_source();
 424                         }
 425                 }
 426         }
 427
 428         boost::rational<std::int64_t> get_speed() const
 429         {
 430                 return speed_ * user_speed_.fetch();
 431         }
 432
 433         draw_frame pop_frame_from_source()
 434         {
 435                 auto frame = source_->receive();
 436
 437                 if (user_speed_.fetch() == 1)
 438                 {
 439                         audio_extractor extractor([this](const const_frame& frame)
 440                         {
 441                                 if (source_channel_layout_ != frame.audio_channel_layout())
 442                                 {
 443                                         source_channel_layout_ = frame.audio_channel_layout();
 444
 445                                         // Insert silence samples so that the audio mixer is guaranteed to be filled.
 446                                         auto min_num_samples_per_frame  = *boost::min_element(destination_audio_cadence_);
 447                                         auto max_num_samples_per_frame  = *boost::max_element(destination_audio_cadence_);
 448                                         auto cadence_safety_samples             = max_num_samples_per_frame - min_num_samples_per_frame;
 449                                         audio_samples_.resize(source_channel_layout_.num_channels * cadence_safety_samples, 0);
 450                                 }
 451
 452                                 auto& buffer = frame.audio_data();
 453                                 audio_samples_.insert(audio_samples_.end(), buffer.begin(), buffer.end());
 454                         });
 455
 456                         frame.accept(extractor);
 457                 }
 458                 else
 459                 {
 460                         source_channel_layout_ = audio_channel_layout::invalid();
 461                         audio_samples_.clear();
 462                 }
 463
 464                 frame.transform().audio_transform.volume = 0.0;
 465
 466                 return frame;
 467         }
 468
 469         draw_frame attach_sound(draw_frame frame)
 470         {
 471                 if (user_speed_.fetch() != 1 || source_channel_layout_ == audio_channel_layout::invalid())
 472                         return frame;
 473
 474                 mutable_audio_buffer buffer;
 475
 476                 if (destination_audio_cadence_.front() * source_channel_layout_.num_channels == audio_samples_.size())
 477                 {
 478                         buffer.swap(audio_samples_);
 479                 }
 480                 else if (audio_samples_.size() >= destination_audio_cadence_.front() * source_channel_layout_.num_channels)
 481                 {
 482                         auto begin      = audio_samples_.begin();
 483                         auto end        = begin + destination_audio_cadence_.front() * source_channel_layout_.num_channels;
 484
 485                         buffer.insert(buffer.begin(), begin, end);
 486                         audio_samples_.erase(begin, end);
 487                 }
 488                 else
 489                 {
 490                         auto needed = destination_audio_cadence_.front();
 491                         auto got = audio_samples_.size() / source_channel_layout_.num_channels;
 492                         if (got != 0) // If at end of stream we don't care
 493                                 CASPAR_LOG(debug) << print() << L" Too few audio samples. Needed " << needed << L" but got " << got;
 494                         buffer.swap(audio_samples_);
 495                         buffer.resize(needed * source_channel_layout_.num_channels, 0);
 496                 }
 497
 498                 boost::range::rotate(destination_audio_cadence_, std::begin(destination_audio_cadence_) + 1);
 499
 500                 auto audio_frame = mutable_frame(
 501                                 {},
 502                                 std::move(buffer),
 503                                 this,
 504                                 pixel_format_desc(),
 505                                 source_channel_layout_);
 506                 return draw_frame::over(frame, draw_frame(std::move(audio_frame)));
 507         }
 508
 509         bool enough_sound() const
 510         {
 511                 return source_channel_layout_ == core::audio_channel_layout::invalid()
 512                                 || user_speed_.fetch() != 1
 513                                 || audio_samples_.size() / source_channel_layout_.num_channels >= destination_audio_cadence_.at(0);
 514         }
 515 };
 516
 517 void describe_framerate_producer(help_sink& sink)
 518 {
 519         sink.para()->text(L"Framerate conversion control / Slow motion examples:");
 520         sink.example(L">> CALL 1-10 FRAMERATE INTERPOLATION BLEND", L"enables 2 frame blend interpolation.");
 521         sink.example(L">> CALL 1-10 FRAMERATE INTERPOLATION BLEND_ALL", L"enables 3 frame blend interpolation.");
 522         sink.example(L">> CALL 1-10 FRAMERATE INTERPOLATION DROP_AND_SKIP", L"disables frame interpolation.");
 523         sink.example(L">> CALL 1-10 FRAMERATE SPEED 0.25", L"immediately changes the speed to 25%. Sound will be disabled.");
 524         sink.example(L">> CALL 1-10 FRAMERATE SPEED 0.25 50", L"changes the speed to 25% linearly over 50 frames. Sound will be disabled.");
 525         sink.example(L">> CALL 1-10 FRAMERATE SPEED 0.25 50 easeinoutsine", L"changes the speed to 25% over 50 frames using specified easing curve. Sound will be disabled.");
 526         sink.example(L">> CALL 1-10 FRAMERATE SPEED 1 50", L"changes the speed to 100% linearly over 50 frames. Sound will be enabled when the destination speed of 100% has been reached.");
 527 }
 528
 529 spl::shared_ptr<frame_producer> create_framerate_producer(
 530                 spl::shared_ptr<frame_producer> source,
 531                 boost::rational<int> source_framerate,
 532                 boost::rational<int> destination_framerate,
 533                 field_mode destination_fieldmode,
 534                 std::vector<int> destination_audio_cadence)
 535 {
 536         return spl::make_shared<framerate_producer>(
 537                         std::move(source),
 538                         std::move(source_framerate),
 539                         std::move(destination_framerate),
 540                         destination_fieldmode,
 541                         std::move(destination_audio_cadence));
 542 }
 543
 544 }}
 545