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

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