git.sesse.net Git - nageru/blob - x264encode.cpp

   1 #include <string.h>
   2 #include <unistd.h>
   3
   4 #include "defs.h"
   5 #include "flags.h"
   6 #include "mux.h"
   7 #include "timebase.h"
   8 #include "x264encode.h"
   9
  10 extern "C" {
  11 #include <libavformat/avformat.h>
  12 }
  13
  14 using namespace std;
  15
  16 X264Encoder::X264Encoder(Mux *mux)
  17         : mux(mux)
  18 {
  19         frame_pool.reset(new uint8_t[WIDTH * HEIGHT * 2 * X264_QUEUE_LENGTH]);
  20         for (unsigned i = 0; i < X264_QUEUE_LENGTH; ++i) {
  21                 free_frames.push(frame_pool.get() + i * (WIDTH * HEIGHT * 2));
  22         }
  23         encoder_thread = thread(&X264Encoder::encoder_thread_func, this);
  24 }
  25
  26 X264Encoder::~X264Encoder()
  27 {
  28         should_quit = true;
  29         queued_frames_nonempty.notify_all();
  30         encoder_thread.join();
  31 }
  32
  33 void X264Encoder::add_frame(int64_t pts, const uint8_t *data)
  34 {
  35         QueuedFrame qf;
  36         qf.pts = pts;
  37
  38         {
  39                 lock_guard<mutex> lock(mu);
  40                 if (free_frames.empty()) {
  41                         fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %ld\n", pts);
  42                         return;
  43                 }
  44
  45                 qf.data = free_frames.front();
  46                 free_frames.pop();
  47         }
  48
  49         memcpy(qf.data, data, WIDTH * HEIGHT * 2);
  50
  51         {
  52                 lock_guard<mutex> lock(mu);
  53                 queued_frames.push(qf);
  54                 queued_frames_nonempty.notify_all();
  55         }
  56 }
  57
  58 void X264Encoder::init_x264()
  59 {
  60         x264_param_t param;
  61         x264_param_default_preset(&param, global_flags.x264_preset.c_str(), global_flags.x264_tune.c_str());
  62
  63         param.i_width = WIDTH;
  64         param.i_height = HEIGHT;
  65         param.i_csp = X264_CSP_NV12;
  66         param.b_vfr_input = 1;
  67         param.i_timebase_num = 1;
  68         param.i_timebase_den = TIMEBASE;
  69         param.i_keyint_max = 50; // About one second.
  70
  71         // NOTE: These should be in sync with the ones in h264encode.cpp (sbs_rbsp()).
  72         param.vui.i_vidformat = 5;  // Unspecified.
  73         param.vui.b_fullrange = 0;
  74         param.vui.i_colorprim = 1;  // BT.709.
  75         param.vui.i_transfer = 2;  // Unspecified (since we use sRGB).
  76         param.vui.i_colmatrix = 6;  // BT.601/SMPTE 170M.
  77
  78         // 4.5 Mbit/sec, CBR.
  79         param.rc.i_rc_method = X264_RC_ABR;
  80         param.rc.i_bitrate = 4500;
  81
  82         // One-second VBV.
  83         param.rc.i_vbv_max_bitrate = 4500;
  84         param.rc.i_vbv_buffer_size = 4500;
  85
  86         // TODO: more flags here, via x264_param_parse().
  87
  88         x264_param_apply_profile(&param, "high");
  89
  90         x264 = x264_encoder_open(&param);
  91         if (x264 == nullptr) {
  92                 fprintf(stderr, "ERROR: x264 initialization failed.\n");
  93                 exit(1);
  94         }
  95 }
  96
  97 void X264Encoder::encoder_thread_func()
  98 {
  99         nice(5);  // Note that x264 further nices some of its threads.
 100         init_x264();
 101
 102         bool frames_left;
 103
 104         do {
 105                 QueuedFrame qf;
 106
 107                 // Wait for a queued frame, then dequeue it.
 108                 {
 109                         unique_lock<mutex> lock(mu);
 110                         queued_frames_nonempty.wait(lock, [this]() { return !queued_frames.empty() || should_quit; });
 111                         if (!queued_frames.empty()) {
 112                                 qf = queued_frames.front();
 113                                 queued_frames.pop();
 114                         } else {
 115                                 qf.pts = -1;
 116                                 qf.data = nullptr;
 117                         }
 118
 119                         frames_left = !queued_frames.empty();
 120                 }
 121
 122                 encode_frame(qf);
 123
 124                 {
 125                         lock_guard<mutex> lock(mu);
 126                         free_frames.push(qf.data);
 127                 }
 128
 129                 // We should quit only if the should_quit flag is set _and_ we have nothing
 130                 // in either queue.
 131         } while (!should_quit || frames_left || x264_encoder_delayed_frames(x264) > 0);
 132
 133         x264_encoder_close(x264);
 134 }
 135
 136 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
 137 {
 138         x264_nal_t *nal = nullptr;
 139         int num_nal = 0;
 140         x264_picture_t pic;
 141
 142         if (qf.data) {
 143                 x264_picture_init(&pic);
 144
 145                 pic.i_pts = qf.pts;
 146                 pic.img.i_csp = X264_CSP_NV12;
 147                 pic.img.i_plane = 2;
 148                 pic.img.plane[0] = qf.data;
 149                 pic.img.i_stride[0] = WIDTH;
 150                 pic.img.plane[1] = qf.data + WIDTH * HEIGHT;
 151                 pic.img.i_stride[1] = WIDTH / 2 * sizeof(uint16_t);
 152
 153                 x264_encoder_encode(x264, &nal, &num_nal, &pic, &pic);
 154         } else {
 155                 x264_encoder_encode(x264, &nal, &num_nal, nullptr, &pic);
 156         }
 157
 158         // We really need one AVPacket for the entire frame, it seems,
 159         // so combine it all.
 160         size_t num_bytes = 0;
 161         for (int i = 0; i < num_nal; ++i) {
 162                 num_bytes += nal[i].i_payload;
 163         }
 164
 165         unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
 166         uint8_t *ptr = data.get();
 167
 168         for (int i = 0; i < num_nal; ++i) {
 169                 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
 170                 ptr += nal[i].i_payload;
 171         }
 172
 173         AVPacket pkt;
 174         memset(&pkt, 0, sizeof(pkt));
 175         pkt.buf = nullptr;
 176         pkt.data = data.get();
 177         pkt.size = num_bytes;
 178         pkt.stream_index = 0;
 179         if (pic.b_keyframe) {
 180                 pkt.flags = AV_PKT_FLAG_KEY;
 181         } else {
 182                 pkt.flags = 0;
 183         }
 184
 185         mux->add_packet(pkt, pic.i_pts, pic.i_dts);
 186 }