git.sesse.net Git - nageru/blob - x264_encoder.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 "x264_encoder.h"
   9
  10 extern "C" {
  11 #include <libavformat/avformat.h>
  12 }
  13
  14 using namespace std;
  15
  16 X264Encoder::X264Encoder(AVOutputFormat *oformat)
  17         : wants_global_headers(oformat->flags & AVFMT_GLOBALHEADER)
  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, int64_t duration, const uint8_t *data)
  34 {
  35         QueuedFrame qf;
  36         qf.pts = pts;
  37         qf.duration = duration;
  38
  39         {
  40                 lock_guard<mutex> lock(mu);
  41                 if (free_frames.empty()) {
  42                         fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %ld\n", pts);
  43                         return;
  44                 }
  45
  46                 qf.data = free_frames.front();
  47                 free_frames.pop();
  48         }
  49
  50         memcpy(qf.data, data, WIDTH * HEIGHT * 2);
  51
  52         {
  53                 lock_guard<mutex> lock(mu);
  54                 queued_frames.push(qf);
  55                 queued_frames_nonempty.notify_all();
  56         }
  57 }
  58
  59 void X264Encoder::init_x264()
  60 {
  61         x264_param_t param;
  62         x264_param_default_preset(&param, global_flags.x264_preset.c_str(), global_flags.x264_tune.c_str());
  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         param.b_repeat_headers = !wants_global_headers;
  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         if (wants_global_headers) {
 100                 x264_nal_t *nal;
 101                 int num_nal;
 102
 103                 x264_encoder_headers(x264, &nal, &num_nal);
 104
 105                 for (int i = 0; i < num_nal; ++i) {
 106                         if (nal[i].i_type == NAL_SEI) {
 107                                 // Don't put the SEI in extradata; make it part of the first frame instead.
 108                                 buffered_sei += string((const char *)nal[i].p_payload, nal[i].i_payload);
 109                         } else {
 110                                 global_headers += string((const char *)nal[i].p_payload, nal[i].i_payload);
 111                         }
 112                 }
 113         }
 114 }
 115
 116 void X264Encoder::encoder_thread_func()
 117 {
 118         nice(5);  // Note that x264 further nices some of its threads.
 119         init_x264();
 120
 121         bool frames_left;
 122
 123         do {
 124                 QueuedFrame qf;
 125
 126                 // Wait for a queued frame, then dequeue it.
 127                 {
 128                         unique_lock<mutex> lock(mu);
 129                         queued_frames_nonempty.wait(lock, [this]() { return !queued_frames.empty() || should_quit; });
 130                         if (!queued_frames.empty()) {
 131                                 qf = queued_frames.front();
 132                                 queued_frames.pop();
 133                         } else {
 134                                 qf.pts = -1;
 135                                 qf.duration = -1;
 136                                 qf.data = nullptr;
 137                         }
 138
 139                         frames_left = !queued_frames.empty();
 140                 }
 141
 142                 encode_frame(qf);
 143
 144                 {
 145                         lock_guard<mutex> lock(mu);
 146                         free_frames.push(qf.data);
 147                 }
 148
 149                 // We should quit only if the should_quit flag is set _and_ we have nothing
 150                 // in either queue.
 151         } while (!should_quit || frames_left || x264_encoder_delayed_frames(x264) > 0);
 152
 153         x264_encoder_close(x264);
 154 }
 155
 156 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
 157 {
 158         x264_nal_t *nal = nullptr;
 159         int num_nal = 0;
 160         x264_picture_t pic;
 161
 162         if (qf.data) {
 163                 x264_picture_init(&pic);
 164
 165                 pic.i_pts = qf.pts;
 166                 pic.img.i_csp = X264_CSP_NV12;
 167                 pic.img.i_plane = 2;
 168                 pic.img.plane[0] = qf.data;
 169                 pic.img.i_stride[0] = WIDTH;
 170                 pic.img.plane[1] = qf.data + WIDTH * HEIGHT;
 171                 pic.img.i_stride[1] = WIDTH / 2 * sizeof(uint16_t);
 172                 pic.opaque = reinterpret_cast<void *>(intptr_t(qf.duration));
 173
 174                 x264_encoder_encode(x264, &nal, &num_nal, &pic, &pic);
 175         } else {
 176                 x264_encoder_encode(x264, &nal, &num_nal, nullptr, &pic);
 177         }
 178
 179         // We really need one AVPacket for the entire frame, it seems,
 180         // so combine it all.
 181         size_t num_bytes = buffered_sei.size();
 182         for (int i = 0; i < num_nal; ++i) {
 183                 num_bytes += nal[i].i_payload;
 184         }
 185
 186         unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
 187         uint8_t *ptr = data.get();
 188
 189         if (!buffered_sei.empty()) {
 190                 memcpy(ptr, buffered_sei.data(), buffered_sei.size());
 191                 ptr += buffered_sei.size();
 192                 buffered_sei.clear();
 193         }
 194         for (int i = 0; i < num_nal; ++i) {
 195                 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
 196                 ptr += nal[i].i_payload;
 197         }
 198
 199         AVPacket pkt;
 200         memset(&pkt, 0, sizeof(pkt));
 201         pkt.buf = nullptr;
 202         pkt.data = data.get();
 203         pkt.size = num_bytes;
 204         pkt.stream_index = 0;
 205         if (pic.b_keyframe) {
 206                 pkt.flags = AV_PKT_FLAG_KEY;
 207         } else {
 208                 pkt.flags = 0;
 209         }
 210         pkt.duration = reinterpret_cast<intptr_t>(pic.opaque);
 211
 212         mux->add_packet(pkt, pic.i_pts, pic.i_dts);
 213 }