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