1 #include "x264_encoder.h"
17 #include "shared/metrics.h"
18 #include "shared/mux.h"
19 #include "print_latency.h"
20 #include "shared/timebase.h"
21 #include "x264_dynamic.h"
22 #include "x264_speed_control.h"
25 #include <libavcodec/avcodec.h>
26 #include <libavformat/avformat.h>
29 using namespace movit;
31 using namespace std::chrono;
32 using namespace std::placeholders;
36 // X264Encoder can be restarted if --record-x264-video is set, so make these
38 atomic<int64_t> metric_x264_queued_frames{0};
39 atomic<int64_t> metric_x264_max_queued_frames{X264_QUEUE_LENGTH};
40 atomic<int64_t> metric_x264_dropped_frames{0};
41 atomic<int64_t> metric_x264_output_frames_i{0};
42 atomic<int64_t> metric_x264_output_frames_p{0};
43 atomic<int64_t> metric_x264_output_frames_b{0};
44 Histogram metric_x264_crf;
45 LatencyHistogram x264_latency_histogram;
47 atomic<int64_t> metric_x264_disk_queued_frames{0};
48 atomic<int64_t> metric_x264_disk_max_queued_frames{X264_QUEUE_LENGTH};
49 atomic<int64_t> metric_x264_disk_dropped_frames{0};
50 atomic<int64_t> metric_x264_disk_output_frames_i{0};
51 atomic<int64_t> metric_x264_disk_output_frames_p{0};
52 atomic<int64_t> metric_x264_disk_output_frames_b{0};
53 Histogram metric_x264_disk_crf;
54 LatencyHistogram x264_disk_latency_histogram;
56 once_flag x264_metrics_inited, x264_disk_metrics_inited;
58 void update_vbv_settings(x264_param_t *param)
60 if (global_flags.x264_bitrate == -1) {
63 param->rc.i_vbv_buffer_size = param->rc.i_bitrate; // One-second VBV.
64 param->rc.i_vbv_max_bitrate = param->rc.i_bitrate; // CBR.
69 X264Encoder::X264Encoder(const AVOutputFormat *oformat, bool use_separate_disk_params)
70 : wants_global_headers(oformat->flags & AVFMT_GLOBALHEADER),
71 use_separate_disk_params(use_separate_disk_params),
72 dyn(load_x264_for_bit_depth(global_flags.bit_depth))
74 if (use_separate_disk_params) {
75 call_once(x264_disk_metrics_inited, []{
76 global_metrics.add("x264_queued_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_queued_frames, Metrics::TYPE_GAUGE);
77 global_metrics.add("x264_max_queued_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_max_queued_frames, Metrics::TYPE_GAUGE);
78 global_metrics.add("x264_dropped_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_dropped_frames);
79 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "i" }}, &metric_x264_disk_output_frames_i);
80 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "p" }}, &metric_x264_disk_output_frames_p);
81 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "b" }}, &metric_x264_disk_output_frames_b);
83 metric_x264_disk_crf.init_uniform(50);
84 global_metrics.add("x264_crf", {{ "encode", "separate_disk" }}, &metric_x264_disk_crf);
85 x264_disk_latency_histogram.init("x264_disk");
88 call_once(use_separate_disk_params ? x264_disk_metrics_inited : x264_metrics_inited, []{
89 global_metrics.add("x264_queued_frames", {{ "encode", "regular" }}, &metric_x264_queued_frames, Metrics::TYPE_GAUGE);
90 global_metrics.add("x264_max_queued_frames", {{ "encode", "regular" }}, &metric_x264_max_queued_frames, Metrics::TYPE_GAUGE);
91 global_metrics.add("x264_dropped_frames", {{ "encode", "regular" }}, &metric_x264_dropped_frames);
92 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "i" }}, &metric_x264_output_frames_i);
93 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "p" }}, &metric_x264_output_frames_p);
94 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "b" }}, &metric_x264_output_frames_b);
96 metric_x264_crf.init_uniform(50);
97 global_metrics.add("x264_crf", {{ "encode", "regular" }}, &metric_x264_crf);
98 x264_latency_histogram.init("x264");
102 size_t bytes_per_pixel = global_flags.bit_depth > 8 ? 2 : 1;
103 frame_pool.reset(new uint8_t[global_flags.width * global_flags.height * 2 * bytes_per_pixel * X264_QUEUE_LENGTH]);
104 for (unsigned i = 0; i < X264_QUEUE_LENGTH; ++i) {
105 free_frames.push(frame_pool.get() + i * (global_flags.width * global_flags.height * 2 * bytes_per_pixel));
107 encoder_thread = thread(&X264Encoder::encoder_thread_func, this);
110 X264Encoder::~X264Encoder()
113 queued_frames_nonempty.notify_all();
114 encoder_thread.join();
120 void X264Encoder::add_frame(int64_t pts, int64_t duration, YCbCrLumaCoefficients ycbcr_coefficients, const uint8_t *data, const ReceivedTimestamps &received_ts)
122 assert(!should_quit);
126 qf.duration = duration;
127 qf.ycbcr_coefficients = ycbcr_coefficients;
128 qf.received_ts = received_ts;
131 lock_guard<mutex> lock(mu);
132 if (free_frames.empty()) {
133 if (use_separate_disk_params) {
134 fprintf(stderr, "WARNING: x264 queue full (disk encoder), dropping frame with pts %" PRId64 "\n", pts);
135 ++metric_x264_disk_dropped_frames;
137 fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %" PRId64 "\n", pts);
138 ++metric_x264_dropped_frames;
143 qf.data = free_frames.front();
147 size_t bytes_per_pixel = global_flags.bit_depth > 8 ? 2 : 1;
148 memcpy(qf.data, data, global_flags.width * global_flags.height * 2 * bytes_per_pixel);
151 lock_guard<mutex> lock(mu);
152 queued_frames.push(qf);
153 queued_frames_nonempty.notify_all();
154 if (use_separate_disk_params) {
155 metric_x264_disk_queued_frames = queued_frames.size();
157 metric_x264_queued_frames = queued_frames.size();
162 void X264Encoder::init_x264()
165 if (use_separate_disk_params) {
166 dyn.x264_param_default_preset(¶m, global_flags.x264_separate_disk_preset.c_str(), global_flags.x264_separate_disk_tune.c_str());
168 dyn.x264_param_default_preset(¶m, global_flags.x264_preset.c_str(), global_flags.x264_tune.c_str());
171 param.i_width = global_flags.width;
172 param.i_height = global_flags.height;
173 param.i_csp = X264_CSP_NV12;
174 if (global_flags.bit_depth > 8) {
175 param.i_csp |= X264_CSP_HIGH_DEPTH;
177 param.b_vfr_input = 1;
178 param.i_timebase_num = 1;
179 param.i_timebase_den = TIMEBASE;
180 param.i_keyint_max = 50; // About one second.
181 if (!use_separate_disk_params && global_flags.x264_speedcontrol) {
182 param.i_frame_reference = 16; // Because speedcontrol is never allowed to change this above what we set at start.
184 #if X264_BUILD >= 153
185 param.i_bitdepth = global_flags.bit_depth;
188 // NOTE: These should be in sync with the ones in quicksync_encoder.cpp (sps_rbsp()).
189 param.vui.i_vidformat = 5; // Unspecified.
190 param.vui.b_fullrange = 0;
191 param.vui.i_colorprim = 1; // BT.709.
192 param.vui.i_transfer = 13; // sRGB.
193 if (global_flags.ycbcr_rec709_coefficients) {
194 param.vui.i_colmatrix = 1; // BT.709.
196 param.vui.i_colmatrix = 6; // BT.601/SMPTE 170M.
199 const double crf = use_separate_disk_params ? global_flags.x264_separate_disk_crf : global_flags.x264_crf;
200 const int bitrate = use_separate_disk_params ? global_flags.x264_separate_disk_bitrate : global_flags.x264_bitrate;
202 param.rc.i_rc_method = X264_RC_CRF;
203 param.rc.f_rf_constant = crf;
205 param.rc.i_rc_method = X264_RC_ABR;
206 param.rc.i_bitrate = bitrate;
208 // If the user wants to cap the max rate, it is also reasonable
209 // to assume that they are fine with the stream constantly
210 // being around that rate even for very low-complexity content;
211 // the obvious and extreme example being a static black picture.
213 // One would think it's fine to have low-complexity content use
214 // less bitrate, but it seems to cause problems in practice;
215 // e.g. VLC seems to often drop the stream (similar to a buffer
216 // underrun) in such cases, but only when streaming from Nageru,
217 // not when reading a dump of the same stream from disk.
218 // I'm not 100% sure whether it's in VLC (possibly some buffering
219 // in the HTTP layer), in microhttpd or somewhere in Nageru itself,
220 // but it's a typical case of problems that can arise. Similarly,
221 // TCP's congestion control is not always fond of the rate staying
222 // low for a while and then rising quickly -- a variation on the same
225 // We solve this by simply asking x264 to fill in dummy bits
226 // in these cases, so that the bitrate stays reasonable constant.
227 // It's a waste of bandwidth, but it makes things go much more
228 // smoothly in these cases. (We don't do it if VBV control is off
229 // in general, not the least because it makes no sense and x264
230 // thus ignores the parameter.)
231 param.rc.b_filler = 1;
233 if (!use_separate_disk_params) {
234 update_vbv_settings(¶m);
237 // Occasionally players have problem with extremely low quantizers;
238 // be on the safe side. Shouldn't affect quality in any meaningful way.
239 param.rc.i_qp_min = 5;
241 const vector<string> &extra_param = use_separate_disk_params ? global_flags.x264_separate_disk_extra_param : global_flags.x264_extra_param;
242 for (const string &str : extra_param) {
243 const size_t pos = str.find(',');
244 if (pos == string::npos) {
245 if (dyn.x264_param_parse(¶m, str.c_str(), nullptr) != 0) {
246 fprintf(stderr, "ERROR: x264 rejected parameter '%s'\n", str.c_str());
249 const string key = str.substr(0, pos);
250 const string value = str.substr(pos + 1);
251 if (dyn.x264_param_parse(¶m, key.c_str(), value.c_str()) != 0) {
252 fprintf(stderr, "ERROR: x264 rejected parameter '%s' set to '%s'\n",
253 key.c_str(), value.c_str());
258 if (global_flags.bit_depth > 8) {
259 dyn.x264_param_apply_profile(¶m, "high10");
261 dyn.x264_param_apply_profile(¶m, "high");
264 param.b_repeat_headers = !wants_global_headers;
266 x264 = dyn.x264_encoder_open(¶m);
267 if (x264 == nullptr) {
268 fprintf(stderr, "ERROR: x264 initialization failed.\n");
272 if (!use_separate_disk_params && global_flags.x264_speedcontrol) {
273 speed_control.reset(new X264SpeedControl(x264, /*f_speed=*/1.0f, X264_QUEUE_LENGTH, /*f_buffer_init=*/1.0f));
276 if (wants_global_headers) {
280 dyn.x264_encoder_headers(x264, &nal, &num_nal);
282 for (int i = 0; i < num_nal; ++i) {
283 if (nal[i].i_type == NAL_SEI) {
284 // Don't put the SEI in extradata; make it part of the first frame instead.
285 buffered_sei += string((const char *)nal[i].p_payload, nal[i].i_payload);
287 global_headers += string((const char *)nal[i].p_payload, nal[i].i_payload);
293 void X264Encoder::encoder_thread_func()
295 if (nice(5) == -1) { // Note that x264 further nices some of its threads.
297 // No exit; it's not fatal.
299 pthread_setname_np(pthread_self(), "x264_encode");
301 x264_init_done = true;
308 // Wait for a queued frame, then dequeue it.
310 unique_lock<mutex> lock(mu);
311 queued_frames_nonempty.wait(lock, [this]() { return !queued_frames.empty() || should_quit; });
312 if (!queued_frames.empty()) {
313 qf = queued_frames.front();
321 if (use_separate_disk_params) {
322 metric_x264_disk_queued_frames = queued_frames.size();
324 metric_x264_queued_frames = queued_frames.size();
326 frames_left = !queued_frames.empty();
332 lock_guard<mutex> lock(mu);
333 free_frames.push(qf.data);
336 // We should quit only if the should_quit flag is set _and_ we have nothing
338 } while (!should_quit || frames_left || dyn.x264_encoder_delayed_frames(x264) > 0);
340 dyn.x264_encoder_close(x264);
343 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
345 x264_nal_t *nal = nullptr;
348 x264_picture_t *input_pic = nullptr;
351 dyn.x264_picture_init(&pic);
354 if (global_flags.bit_depth > 8) {
355 pic.img.i_csp = X264_CSP_NV12 | X264_CSP_HIGH_DEPTH;
357 pic.img.plane[0] = qf.data;
358 pic.img.i_stride[0] = global_flags.width * sizeof(uint16_t);
359 pic.img.plane[1] = qf.data + global_flags.width * global_flags.height * sizeof(uint16_t);
360 pic.img.i_stride[1] = global_flags.width / 2 * sizeof(uint32_t);
362 pic.img.i_csp = X264_CSP_NV12;
364 pic.img.plane[0] = qf.data;
365 pic.img.i_stride[0] = global_flags.width;
366 pic.img.plane[1] = qf.data + global_flags.width * global_flags.height;
367 pic.img.i_stride[1] = global_flags.width / 2 * sizeof(uint16_t);
369 pic.opaque = reinterpret_cast<void *>(intptr_t(qf.duration));
373 frames_being_encoded[qf.pts] = qf.received_ts;
376 unsigned new_rate = new_bitrate_kbit.load(); // Can be 0 for no change.
378 speed_control->set_config_override_function(bind(&speed_control_override_func, new_rate, qf.ycbcr_coefficients, _1));
381 dyn.x264_encoder_parameters(x264, ¶m);
382 speed_control_override_func(new_rate, qf.ycbcr_coefficients, ¶m);
383 dyn.x264_encoder_reconfig(x264, ¶m);
387 float queue_fill_ratio;
389 lock_guard<mutex> lock(mu);
390 queue_fill_ratio = float(free_frames.size()) / X264_QUEUE_LENGTH;
392 speed_control->before_frame(queue_fill_ratio, X264_QUEUE_LENGTH, 1e6 * qf.duration / TIMEBASE);
394 dyn.x264_encoder_encode(x264, &nal, &num_nal, input_pic, &pic);
396 speed_control->after_frame();
399 if (num_nal == 0) return;
401 if (use_separate_disk_params) {
402 if (IS_X264_TYPE_I(pic.i_type)) {
403 ++metric_x264_disk_output_frames_i;
404 } else if (IS_X264_TYPE_B(pic.i_type)) {
405 ++metric_x264_disk_output_frames_b;
407 ++metric_x264_disk_output_frames_p;
410 metric_x264_disk_crf.count_event(pic.prop.f_crf_avg);
412 if (IS_X264_TYPE_I(pic.i_type)) {
413 ++metric_x264_output_frames_i;
414 } else if (IS_X264_TYPE_B(pic.i_type)) {
415 ++metric_x264_output_frames_b;
417 ++metric_x264_output_frames_p;
420 metric_x264_crf.count_event(pic.prop.f_crf_avg);
423 if (frames_being_encoded.count(pic.i_pts)) {
424 ReceivedTimestamps received_ts = frames_being_encoded[pic.i_pts];
425 frames_being_encoded.erase(pic.i_pts);
427 static int frameno = 0;
428 print_latency("Current x264 latency (video inputs → network mux):",
429 received_ts, (pic.i_type == X264_TYPE_B || pic.i_type == X264_TYPE_BREF),
430 &frameno, &x264_latency_histogram);
435 // We really need one AVPacket for the entire frame, it seems,
436 // so combine it all.
437 size_t num_bytes = buffered_sei.size();
438 for (int i = 0; i < num_nal; ++i) {
439 num_bytes += nal[i].i_payload;
442 unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
443 uint8_t *ptr = data.get();
445 if (!buffered_sei.empty()) {
446 memcpy(ptr, buffered_sei.data(), buffered_sei.size());
447 ptr += buffered_sei.size();
448 buffered_sei.clear();
450 for (int i = 0; i < num_nal; ++i) {
451 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
452 ptr += nal[i].i_payload;
456 memset(&pkt, 0, sizeof(pkt));
458 pkt.data = data.get();
459 pkt.size = num_bytes;
460 pkt.stream_index = 0;
461 if (pic.b_keyframe) {
462 pkt.flags = AV_PKT_FLAG_KEY;
466 pkt.duration = reinterpret_cast<intptr_t>(pic.opaque);
468 for (Mux *mux : muxes) {
469 mux->add_packet(pkt, pic.i_pts, pic.i_dts);
473 void X264Encoder::speed_control_override_func(unsigned bitrate_kbit, movit::YCbCrLumaCoefficients ycbcr_coefficients, x264_param_t *param)
475 if (bitrate_kbit != 0) {
476 param->rc.i_bitrate = bitrate_kbit;
477 update_vbv_settings(param);
480 if (ycbcr_coefficients == YCBCR_REC_709) {
481 param->vui.i_colmatrix = 1; // BT.709.
483 assert(ycbcr_coefficients == YCBCR_REC_601);
484 param->vui.i_colmatrix = 6; // BT.601/SMPTE 170M.