git.sesse.net Git - nageru/blob - mixer.h

   1 #ifndef _MIXER_H
   2 #define _MIXER_H 1
   3
   4 // The actual video mixer, running in its own separate background thread.
   5
   6 #include <epoxy/gl.h>
   7 #undef Success
   8 #include <movit/effect_chain.h>
   9 #include <movit/flat_input.h>
  10 #include <functional>
  11
  12 #include "bmusb/bmusb.h"
  13 #include "h264encode.h"
  14 #include "pbo_frame_allocator.h"
  15 #include "ref_counted_frame.h"
  16 #include "ref_counted_gl_sync.h"
  17 #include "theme.h"
  18 #include "resampler.h"
  19 #include "timebase.h"
  20
  21 #define NUM_CARDS 2
  22
  23 namespace movit {
  24 class YCbCrInput;
  25 }
  26 class QOpenGLContext;
  27 class QSurfaceFormat;
  28
  29 class Mixer {
  30 public:
  31         // The surface format is used for offscreen destinations for OpenGL contexts we need.
  32         Mixer(const QSurfaceFormat &format);
  33         ~Mixer();
  34         void start();
  35         void quit();
  36
  37         void transition_clicked(int transition_num);
  38         void channel_clicked(int preview_num);
  39
  40         enum Output {
  41                 OUTPUT_LIVE = 0,
  42                 OUTPUT_PREVIEW,
  43                 OUTPUT_INPUT0,
  44                 OUTPUT_INPUT1,
  45                 OUTPUT_INPUT2,
  46                 OUTPUT_INPUT3,
  47                 NUM_OUTPUTS
  48         };
  49
  50         struct DisplayFrame {
  51                 // The chain for rendering this frame. To render a display frame,
  52                 // first wait for <ready_fence>, then call <setup_chain>
  53                 // to wire up all the inputs, and then finally call
  54                 // chain->render_to_screen() or similar.
  55                 movit::EffectChain *chain;
  56                 std::function<void()> setup_chain;
  57
  58                 // Asserted when all the inputs are ready; you cannot render the chain
  59                 // before this.
  60                 RefCountedGLsync ready_fence;
  61
  62                 // Holds on to all the input frames needed for this display frame,
  63                 // so they are not released while still rendering.
  64                 std::vector<RefCountedFrame> input_frames;
  65
  66                 // Textures that should be released back to the resource pool
  67                 // when this frame disappears, if any.
  68                 // TODO: Refcount these as well?
  69                 std::vector<GLuint> temp_textures;
  70         };
  71         // Implicitly frees the previous one if there's a new frame available.
  72         bool get_display_frame(Output output, DisplayFrame *frame) {
  73                 return output_channel[output].get_display_frame(frame);
  74         }
  75
  76         typedef std::function<void()> new_frame_ready_callback_t;
  77         void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
  78         {
  79                 output_channel[output].set_frame_ready_callback(callback);
  80         }
  81
  82         std::vector<std::string> get_transition_names()
  83         {
  84                 return theme->get_transition_names(pts());
  85         }
  86
  87 private:
  88         void bm_frame(int card_index, uint16_t timecode,
  89                 FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
  90                 FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format);
  91         void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
  92         void thread_func();
  93         void subsample_chroma(GLuint src_tex, GLuint dst_dst);
  94         void release_display_frame(DisplayFrame *frame);
  95         double pts() { return double(pts_int) / TIMEBASE; }
  96
  97         QSurface *mixer_surface, *h264_encoder_surface;
  98         std::unique_ptr<movit::ResourcePool> resource_pool;
  99         std::unique_ptr<Theme> theme;
 100         std::unique_ptr<movit::EffectChain> display_chain;
 101         GLuint cbcr_program_num;  // Owned by <resource_pool>.
 102         std::unique_ptr<H264Encoder> h264_encoder;
 103
 104         // Effects part of <display_chain>. Owned by <display_chain>.
 105         movit::FlatInput *display_input;
 106
 107         int64_t pts_int = 0;  // In TIMEBASE units.
 108
 109         std::mutex bmusb_mutex;
 110         struct CaptureCard {
 111                 BMUSBCapture *usb;
 112                 std::unique_ptr<PBOFrameAllocator> frame_allocator;
 113
 114                 // Stuff for the OpenGL context (for texture uploading).
 115                 QSurface *surface;
 116                 QOpenGLContext *context;
 117
 118                 bool new_data_ready = false;  // Whether new_frame and new_frame_audio contains anything.
 119                 bool should_quit = false;
 120                 RefCountedFrame new_frame;
 121                 GLsync new_data_ready_fence;  // Whether new_frame is ready for rendering.
 122                 std::vector<float> new_frame_audio;
 123                 std::condition_variable new_data_ready_changed;  // Set whenever new_data_ready is changed.
 124                 unsigned dropped_frames = 0;  // Before new_frame.
 125
 126                 std::mutex audio_mutex;
 127                 std::unique_ptr<Resampler> resampler;  // Under audio_mutex.
 128                 int last_timecode = -1;  // Unwrapped.
 129         };
 130         CaptureCard cards[NUM_CARDS];  // protected by <bmusb_mutex>
 131
 132         RefCountedFrame bmusb_current_rendering_frame[NUM_CARDS];
 133
 134         class OutputChannel {
 135         public:
 136                 ~OutputChannel();
 137                 void output_frame(DisplayFrame frame);
 138                 bool get_display_frame(DisplayFrame *frame);
 139                 void set_frame_ready_callback(new_frame_ready_callback_t callback);
 140
 141         private:
 142                 friend class Mixer;
 143
 144                 Mixer *parent = nullptr;  // Not owned.
 145                 std::mutex frame_mutex;
 146                 DisplayFrame current_frame, ready_frame;  // protected by <frame_mutex>
 147                 bool has_current_frame = false, has_ready_frame = false;  // protected by <frame_mutex>
 148                 new_frame_ready_callback_t new_frame_ready_callback;
 149                 bool has_new_frame_ready_callback = false;
 150         };
 151         OutputChannel output_channel[NUM_OUTPUTS];
 152
 153         std::thread mixer_thread;
 154         bool should_quit = false;
 155 };
 156
 157 extern Mixer *global_mixer;
 158
 159 #endif  // !defined(_MIXER_H)