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 <ebur128.h>
  11 #include <functional>
  12
  13 #include "bmusb/bmusb.h"
  14 #include "h264encode.h"
  15 #include "pbo_frame_allocator.h"
  16 #include "ref_counted_frame.h"
  17 #include "ref_counted_gl_sync.h"
  18 #include "theme.h"
  19 #include "resampler.h"
  20 #include "timebase.h"
  21 #include "httpd.h"
  22
  23 #define NUM_CARDS 2
  24
  25 namespace movit {
  26 class YCbCrInput;
  27 }
  28 class QOpenGLContext;
  29 class QSurfaceFormat;
  30
  31 class Mixer {
  32 public:
  33         // The surface format is used for offscreen destinations for OpenGL contexts we need.
  34         Mixer(const QSurfaceFormat &format);
  35         ~Mixer();
  36         void start();
  37         void quit();
  38
  39         void transition_clicked(int transition_num);
  40         void channel_clicked(int preview_num);
  41
  42         enum Output {
  43                 OUTPUT_LIVE = 0,
  44                 OUTPUT_PREVIEW,
  45                 OUTPUT_INPUT0,
  46                 OUTPUT_INPUT1,
  47                 OUTPUT_INPUT2,
  48                 OUTPUT_INPUT3,
  49                 NUM_OUTPUTS
  50         };
  51
  52         struct DisplayFrame {
  53                 // The chain for rendering this frame. To render a display frame,
  54                 // first wait for <ready_fence>, then call <setup_chain>
  55                 // to wire up all the inputs, and then finally call
  56                 // chain->render_to_screen() or similar.
  57                 movit::EffectChain *chain;
  58                 std::function<void()> setup_chain;
  59
  60                 // Asserted when all the inputs are ready; you cannot render the chain
  61                 // before this.
  62                 RefCountedGLsync ready_fence;
  63
  64                 // Holds on to all the input frames needed for this display frame,
  65                 // so they are not released while still rendering.
  66                 std::vector<RefCountedFrame> input_frames;
  67
  68                 // Textures that should be released back to the resource pool
  69                 // when this frame disappears, if any.
  70                 // TODO: Refcount these as well?
  71                 std::vector<GLuint> temp_textures;
  72         };
  73         // Implicitly frees the previous one if there's a new frame available.
  74         bool get_display_frame(Output output, DisplayFrame *frame) {
  75                 return output_channel[output].get_display_frame(frame);
  76         }
  77
  78         typedef std::function<void()> new_frame_ready_callback_t;
  79         void set_frame_ready_callback(Output output, new_frame_ready_callback_t callback)
  80         {
  81                 output_channel[output].set_frame_ready_callback(callback);
  82         }
  83
  84         typedef std::function<void(float, float, float, float, float)> audio_level_callback_t;
  85         void set_audio_level_callback(audio_level_callback_t callback)
  86         {
  87                 audio_level_callback = callback;
  88         }
  89
  90         std::vector<std::string> get_transition_names()
  91         {
  92                 return theme->get_transition_names(pts());
  93         }
  94
  95 private:
  96         void bm_frame(int card_index, uint16_t timecode,
  97                 FrameAllocator::Frame video_frame, size_t video_offset, uint16_t video_format,
  98                 FrameAllocator::Frame audio_frame, size_t audio_offset, uint16_t audio_format);
  99         void place_rectangle(movit::Effect *resample_effect, movit::Effect *padding_effect, float x0, float y0, float x1, float y1);
 100         void thread_func();
 101         void subsample_chroma(GLuint src_tex, GLuint dst_dst);
 102         void release_display_frame(DisplayFrame *frame);
 103         double pts() { return double(pts_int) / TIMEBASE; }
 104
 105         HTTPD httpd;
 106
 107         QSurface *mixer_surface, *h264_encoder_surface;
 108         std::unique_ptr<movit::ResourcePool> resource_pool;
 109         std::unique_ptr<Theme> theme;
 110         std::unique_ptr<movit::EffectChain> display_chain;
 111         GLuint cbcr_program_num;  // Owned by <resource_pool>.
 112         std::unique_ptr<H264Encoder> h264_encoder;
 113
 114         // Effects part of <display_chain>. Owned by <display_chain>.
 115         movit::FlatInput *display_input;
 116
 117         int64_t pts_int = 0;  // In TIMEBASE units.
 118
 119         std::mutex bmusb_mutex;
 120         struct CaptureCard {
 121                 BMUSBCapture *usb;
 122                 std::unique_ptr<PBOFrameAllocator> frame_allocator;
 123
 124                 // Stuff for the OpenGL context (for texture uploading).
 125                 QSurface *surface;
 126                 QOpenGLContext *context;
 127
 128                 bool new_data_ready = false;  // Whether new_frame and new_frame_audio contains anything.
 129                 bool should_quit = false;
 130                 RefCountedFrame new_frame;
 131                 GLsync new_data_ready_fence;  // Whether new_frame is ready for rendering.
 132                 std::vector<float> new_frame_audio;
 133                 std::condition_variable new_data_ready_changed;  // Set whenever new_data_ready is changed.
 134                 unsigned dropped_frames = 0;  // Before new_frame.
 135
 136                 std::mutex audio_mutex;
 137                 std::unique_ptr<Resampler> resampler;  // Under audio_mutex.
 138                 int last_timecode = -1;  // Unwrapped.
 139         };
 140         CaptureCard cards[NUM_CARDS];  // protected by <bmusb_mutex>
 141
 142         RefCountedFrame bmusb_current_rendering_frame[NUM_CARDS];
 143
 144         class OutputChannel {
 145         public:
 146                 ~OutputChannel();
 147                 void output_frame(DisplayFrame frame);
 148                 bool get_display_frame(DisplayFrame *frame);
 149                 void set_frame_ready_callback(new_frame_ready_callback_t callback);
 150
 151         private:
 152                 friend class Mixer;
 153
 154                 Mixer *parent = nullptr;  // Not owned.
 155                 std::mutex frame_mutex;
 156                 DisplayFrame current_frame, ready_frame;  // protected by <frame_mutex>
 157                 bool has_current_frame = false, has_ready_frame = false;  // protected by <frame_mutex>
 158                 new_frame_ready_callback_t new_frame_ready_callback;
 159                 bool has_new_frame_ready_callback = false;
 160         };
 161         OutputChannel output_channel[NUM_OUTPUTS];
 162
 163         std::thread mixer_thread;
 164         bool should_quit = false;
 165
 166         audio_level_callback_t audio_level_callback = nullptr;
 167         ebur128_state *r128_state = nullptr;
 168 };
 169
 170 extern Mixer *global_mixer;
 171
 172 #endif  // !defined(_MIXER_H)