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         // TODO: close x264
  29 }
  30
  31 void X264Encoder::add_frame(int64_t pts, const uint8_t *data)
  32 {
  33         QueuedFrame qf;
  34         qf.pts = pts;
  35
  36         {
  37                 lock_guard<mutex> lock(mu);
  38                 if (free_frames.empty()) {
  39                         fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %ld\n", pts);
  40                         return;
  41                 }
  42
  43                 qf.data = free_frames.front();
  44                 free_frames.pop();
  45         }
  46
  47         memcpy(qf.data, data, WIDTH * HEIGHT * 2);
  48
  49         {
  50                 lock_guard<mutex> lock(mu);
  51                 queued_frames.push(qf);
  52                 queued_frames_nonempty.notify_all();
  53         }
  54 }
  55
  56 void X264Encoder::end_encoding()
  57 {
  58         // TODO
  59 }
  60
  61 void X264Encoder::init_x264()
  62 {
  63         x264_param_t param;
  64         x264_param_default_preset(&param, global_flags.x264_preset.c_str(), global_flags.x264_tune.c_str());
  65
  66         param.i_width = WIDTH;
  67         param.i_height = HEIGHT;
  68         param.i_csp = X264_CSP_NV12;
  69         param.b_vfr_input = 1;
  70         param.i_timebase_num = 1;
  71         param.i_timebase_den = TIMEBASE;
  72         param.i_keyint_max = 50; // About one second.
  73
  74         // NOTE: These should be in sync with the ones in h264encode.cpp (sbs_rbsp()).
  75         param.vui.i_vidformat = 5;  // Unspecified.
  76         param.vui.b_fullrange = 0;
  77         param.vui.i_colorprim = 1;  // BT.709.
  78         param.vui.i_transfer = 2;  // Unspecified (since we use sRGB).
  79         param.vui.i_colmatrix = 6;  // BT.601/SMPTE 170M.
  80
  81         // 4.5 Mbit/sec, CBR.
  82         param.rc.i_rc_method = X264_RC_ABR;
  83         param.rc.i_bitrate = 4500;
  84
  85         // One-second VBV.
  86         param.rc.i_vbv_max_bitrate = 4500;
  87         param.rc.i_vbv_buffer_size = 4500;
  88
  89         // TODO: more flags here, via x264_param_parse().
  90
  91         x264_param_apply_profile(&param, "high");
  92
  93         x264 = x264_encoder_open(&param);
  94         if (x264 == nullptr) {
  95                 fprintf(stderr, "ERROR: x264 initialization failed.\n");
  96                 exit(1);
  97         }
  98 }
  99
 100 void X264Encoder::encoder_thread_func()
 101 {
 102         nice(5);  // Note that x264 further nices some of its threads.
 103         init_x264();
 104
 105         for ( ;; ) {
 106                 QueuedFrame qf;
 107
 108                 // Wait for a queued frame, then dequeue it.
 109                 {
 110                         unique_lock<mutex> lock(mu);
 111                         queued_frames_nonempty.wait(lock, [this]() { return !queued_frames.empty(); });
 112                         qf = queued_frames.front();
 113                         queued_frames.pop();
 114                 }
 115
 116                 encode_frame(qf);
 117
 118                 {
 119                         lock_guard<mutex> lock(mu);
 120                         free_frames.push(qf.data);
 121                 }
 122         }
 123 }
 124
 125 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
 126 {
 127         x264_picture_t pic;
 128         x264_nal_t *nal = nullptr;
 129         int num_nal = 0;
 130
 131         x264_picture_init(&pic);
 132
 133         // TODO: Delayed frames.
 134         pic.i_pts = qf.pts;
 135         pic.img.i_csp = X264_CSP_NV12;
 136         pic.img.i_plane = 2;
 137         pic.img.plane[0] = qf.data;
 138         pic.img.i_stride[0] = WIDTH;
 139         pic.img.plane[1] = qf.data + WIDTH * HEIGHT;
 140         pic.img.i_stride[1] = WIDTH / 2 * sizeof(uint16_t);
 141
 142         x264_encoder_encode(x264, &nal, &num_nal, &pic, &pic);
 143
 144         // We really need one AVPacket for the entire frame, it seems,
 145         // so combine it all.
 146         size_t num_bytes = 0;
 147         for (int i = 0; i < num_nal; ++i) {
 148                 num_bytes += nal[i].i_payload;
 149         }
 150
 151         unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
 152         uint8_t *ptr = data.get();
 153
 154         for (int i = 0; i < num_nal; ++i) {
 155                 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
 156                 ptr += nal[i].i_payload;
 157         }
 158
 159         AVPacket pkt;
 160         memset(&pkt, 0, sizeof(pkt));
 161         pkt.buf = nullptr;
 162         pkt.data = data.get();
 163         pkt.size = num_bytes;
 164         pkt.stream_index = 0;
 165         if (pic.b_keyframe) {
 166                 pkt.flags = AV_PKT_FLAG_KEY;
 167         } else {
 168                 pkt.flags = 0;
 169         }
 170
 171         mux->add_packet(pkt, pic.i_pts, pic.i_dts);
 172 }