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

   1 #include <string.h>
   2 #include <unistd.h>
   3
   4 #include "defs.h"
   5 #include "mux.h"
   6 #include "timebase.h"
   7 #include "x264encode.h"
   8
   9 extern "C" {
  10 #include <libavformat/avformat.h>
  11 }
  12
  13 using namespace std;
  14
  15 X264Encoder::X264Encoder(Mux *mux)
  16         : mux(mux)
  17 {
  18         frame_pool.reset(new uint8_t[WIDTH * HEIGHT * 2 * X264_QUEUE_LENGTH]);
  19         for (unsigned i = 0; i < X264_QUEUE_LENGTH; ++i) {
  20                 free_frames.push(frame_pool.get() + i * (WIDTH * HEIGHT * 2));
  21         }
  22         encoder_thread = thread(&X264Encoder::encoder_thread_func, this);
  23 }
  24
  25 X264Encoder::~X264Encoder()
  26 {
  27         // TODO: close x264
  28 }
  29
  30 void X264Encoder::add_frame(int64_t pts, const uint8_t *data)
  31 {
  32         QueuedFrame qf;
  33         qf.pts = pts;
  34
  35         {
  36                 lock_guard<mutex> lock(mu);
  37                 if (free_frames.empty()) {
  38                         fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %ld\n", pts);
  39                         return;
  40                 }
  41
  42                 qf.data = free_frames.front();
  43                 free_frames.pop();
  44         }
  45
  46         memcpy(qf.data, data, WIDTH * HEIGHT * 2);
  47
  48         {
  49                 lock_guard<mutex> lock(mu);
  50                 queued_frames.push(qf);
  51                 queued_frames_nonempty.notify_all();
  52         }
  53 }
  54
  55 void X264Encoder::end_encoding()
  56 {
  57         // TODO
  58 }
  59
  60 void X264Encoder::init_x264()
  61 {
  62         x264_param_t param;
  63         x264_param_default_preset(&param, "ultrafast", "film");  // TODO: flags
  64
  65         param.i_width = WIDTH;
  66         param.i_height = HEIGHT;
  67         param.i_csp = X264_CSP_NV12;
  68         param.b_vfr_input = 1;
  69         param.i_timebase_num = 1;
  70         param.i_timebase_den = TIMEBASE;
  71         param.i_keyint_max = 50; // About one second.
  72
  73         // NOTE: These should be in sync with the ones in h264encode.cpp (sbs_rbsp()).
  74         param.vui.i_vidformat = 5;  // Unspecified.
  75         param.vui.b_fullrange = 0;
  76         param.vui.i_colorprim = 1;  // BT.709.
  77         param.vui.i_transfer = 2;  // Unspecified (since we use sRGB).
  78         param.vui.i_colmatrix = 6;  // BT.601/SMPTE 170M.
  79
  80         // 4.5 Mbit/sec, CBR.
  81         param.rc.i_rc_method = X264_RC_ABR;
  82         param.rc.i_bitrate = 4500;
  83
  84         // One-second VBV.
  85         param.rc.i_vbv_max_bitrate = 4500;
  86         param.rc.i_vbv_buffer_size = 4500;
  87
  88         // TODO: more flags here, via x264_param_parse().
  89
  90         x264_param_apply_profile(&param, "high");
  91
  92         x264 = x264_encoder_open(&param);
  93         if (x264 == nullptr) {
  94                 fprintf(stderr, "ERROR: x264 initialization failed.\n");
  95                 exit(1);
  96         }
  97 }
  98
  99 void X264Encoder::encoder_thread_func()
 100 {
 101         nice(5);  // Note that x264 further nices some of its threads.
 102         init_x264();
 103
 104         for ( ;; ) {
 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(); });
 111                         qf = queued_frames.front();
 112                         queued_frames.pop();
 113                 }
 114
 115                 encode_frame(qf);
 116
 117                 {
 118                         lock_guard<mutex> lock(mu);
 119                         free_frames.push(qf.data);
 120                 }
 121         }
 122 }
 123
 124 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
 125 {
 126         x264_picture_t pic;
 127         x264_nal_t *nal = nullptr;
 128         int num_nal = 0;
 129
 130         x264_picture_init(&pic);
 131
 132         // TODO: Delayed frames.
 133         pic.i_pts = qf.pts;
 134         pic.img.i_csp = X264_CSP_NV12;
 135         pic.img.i_plane = 2;
 136         pic.img.plane[0] = qf.data;
 137         pic.img.i_stride[0] = WIDTH;
 138         pic.img.plane[1] = qf.data + WIDTH * HEIGHT;
 139         pic.img.i_stride[1] = WIDTH / 2 * sizeof(uint16_t);
 140
 141         x264_encoder_encode(x264, &nal, &num_nal, &pic, &pic);
 142
 143         // We really need one AVPacket for the entire frame, it seems,
 144         // so combine it all.
 145         size_t num_bytes = 0;
 146         for (int i = 0; i < num_nal; ++i) {
 147                 num_bytes += nal[i].i_payload;
 148         }
 149
 150         unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
 151         uint8_t *ptr = data.get();
 152
 153         for (int i = 0; i < num_nal; ++i) {
 154                 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
 155                 ptr += nal[i].i_payload;
 156         }
 157
 158         AVPacket pkt;
 159         memset(&pkt, 0, sizeof(pkt));
 160         pkt.buf = nullptr;
 161         pkt.data = data.get();
 162         pkt.size = num_bytes;
 163         pkt.stream_index = 0;
 164         if (pic.b_keyframe) {
 165                 pkt.flags = AV_PKT_FLAG_KEY;
 166         } else {
 167                 pkt.flags = 0;
 168         }
 169
 170         mux->add_packet(pkt, pic.i_pts, pic.i_dts);
 171 }