1 #include "x264_encoder.h"
11 #include <movit/image_format.h>
25 #include "shared/metrics.h"
26 #include "shared/mux.h"
27 #include "print_latency.h"
28 #include "shared/timebase.h"
29 #include "x264_dynamic.h"
30 #include "x264_speed_control.h"
33 #include <libavcodec/packet.h>
34 #include <libavformat/avformat.h>
37 using namespace movit;
39 using namespace std::chrono;
40 using namespace std::placeholders;
44 // X264Encoder can be restarted if --record-x264-video is set, so make these
46 atomic<int64_t> metric_x264_queued_frames{0};
47 atomic<int64_t> metric_x264_max_queued_frames{X264_QUEUE_LENGTH};
48 atomic<int64_t> metric_x264_dropped_frames{0};
49 atomic<int64_t> metric_x264_output_frames_i{0};
50 atomic<int64_t> metric_x264_output_frames_p{0};
51 atomic<int64_t> metric_x264_output_frames_b{0};
52 Histogram metric_x264_crf;
53 LatencyHistogram x264_latency_histogram;
55 atomic<int64_t> metric_x264_disk_queued_frames{0};
56 atomic<int64_t> metric_x264_disk_max_queued_frames{X264_QUEUE_LENGTH};
57 atomic<int64_t> metric_x264_disk_dropped_frames{0};
58 atomic<int64_t> metric_x264_disk_output_frames_i{0};
59 atomic<int64_t> metric_x264_disk_output_frames_p{0};
60 atomic<int64_t> metric_x264_disk_output_frames_b{0};
61 Histogram metric_x264_disk_crf;
62 LatencyHistogram x264_disk_latency_histogram;
64 once_flag x264_metrics_inited, x264_disk_metrics_inited;
66 void update_vbv_settings(x264_param_t *param)
68 if (global_flags.x264_bitrate == -1) {
71 param->rc.i_vbv_buffer_size = param->rc.i_bitrate; // One-second VBV.
72 param->rc.i_vbv_max_bitrate = param->rc.i_bitrate; // CBR.
77 X264Encoder::X264Encoder(const AVOutputFormat *oformat, bool use_separate_disk_params)
78 : wants_global_headers(oformat->flags & AVFMT_GLOBALHEADER),
79 use_separate_disk_params(use_separate_disk_params),
80 dyn(load_x264_for_bit_depth(global_flags.bit_depth))
82 if (use_separate_disk_params) {
83 call_once(x264_disk_metrics_inited, []{
84 global_metrics.add("x264_queued_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_queued_frames, Metrics::TYPE_GAUGE);
85 global_metrics.add("x264_max_queued_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_max_queued_frames, Metrics::TYPE_GAUGE);
86 global_metrics.add("x264_dropped_frames", {{ "encode", "separate_disk" }}, &metric_x264_disk_dropped_frames);
87 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "i" }}, &metric_x264_disk_output_frames_i);
88 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "p" }}, &metric_x264_disk_output_frames_p);
89 global_metrics.add("x264_output_frames", {{ "encode", "separate_disk" }, { "type", "b" }}, &metric_x264_disk_output_frames_b);
91 metric_x264_disk_crf.init_uniform(50);
92 global_metrics.add("x264_crf", {{ "encode", "separate_disk" }}, &metric_x264_disk_crf);
93 x264_disk_latency_histogram.init("x264_disk");
96 call_once(use_separate_disk_params ? x264_disk_metrics_inited : x264_metrics_inited, []{
97 global_metrics.add("x264_queued_frames", {{ "encode", "regular" }}, &metric_x264_queued_frames, Metrics::TYPE_GAUGE);
98 global_metrics.add("x264_max_queued_frames", {{ "encode", "regular" }}, &metric_x264_max_queued_frames, Metrics::TYPE_GAUGE);
99 global_metrics.add("x264_dropped_frames", {{ "encode", "regular" }}, &metric_x264_dropped_frames);
100 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "i" }}, &metric_x264_output_frames_i);
101 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "p" }}, &metric_x264_output_frames_p);
102 global_metrics.add("x264_output_frames", {{ "encode", "regular" }, { "type", "b" }}, &metric_x264_output_frames_b);
104 metric_x264_crf.init_uniform(50);
105 global_metrics.add("x264_crf", {{ "encode", "regular" }}, &metric_x264_crf);
106 x264_latency_histogram.init("x264");
110 size_t bytes_per_pixel = global_flags.bit_depth > 8 ? 2 : 1;
111 frame_pool.reset(new uint8_t[global_flags.width * global_flags.height * 2 * bytes_per_pixel * X264_QUEUE_LENGTH]);
112 for (unsigned i = 0; i < X264_QUEUE_LENGTH; ++i) {
113 free_frames.push(frame_pool.get() + i * (global_flags.width * global_flags.height * 2 * bytes_per_pixel));
115 encoder_thread = thread(&X264Encoder::encoder_thread_func, this);
118 X264Encoder::~X264Encoder()
121 queued_frames_nonempty.notify_all();
122 encoder_thread.join();
128 void X264Encoder::add_frame(int64_t pts, int64_t duration, YCbCrLumaCoefficients ycbcr_coefficients, const uint8_t *data, const ReceivedTimestamps &received_ts)
130 assert(!should_quit);
134 qf.duration = duration;
135 qf.ycbcr_coefficients = ycbcr_coefficients;
136 qf.received_ts = received_ts;
139 lock_guard<mutex> lock(mu);
140 if (free_frames.empty()) {
141 if (use_separate_disk_params) {
142 fprintf(stderr, "WARNING: x264 queue full (disk encoder), dropping frame with pts %" PRId64 "\n", pts);
143 ++metric_x264_disk_dropped_frames;
145 fprintf(stderr, "WARNING: x264 queue full, dropping frame with pts %" PRId64 "\n", pts);
146 ++metric_x264_dropped_frames;
151 qf.data = free_frames.front();
155 size_t bytes_per_pixel = global_flags.bit_depth > 8 ? 2 : 1;
156 memcpy(qf.data, data, global_flags.width * global_flags.height * 2 * bytes_per_pixel);
159 lock_guard<mutex> lock(mu);
160 queued_frames.push(qf);
161 queued_frames_nonempty.notify_all();
162 if (use_separate_disk_params) {
163 metric_x264_disk_queued_frames = queued_frames.size();
165 metric_x264_queued_frames = queued_frames.size();
170 void X264Encoder::init_x264()
173 if (use_separate_disk_params) {
174 dyn.x264_param_default_preset(¶m, global_flags.x264_separate_disk_preset.c_str(), global_flags.x264_separate_disk_tune.c_str());
176 dyn.x264_param_default_preset(¶m, global_flags.x264_preset.c_str(), global_flags.x264_tune.c_str());
179 param.i_width = global_flags.width;
180 param.i_height = global_flags.height;
181 param.i_csp = X264_CSP_NV12;
182 if (global_flags.bit_depth > 8) {
183 param.i_csp |= X264_CSP_HIGH_DEPTH;
185 param.b_vfr_input = 1;
186 param.i_timebase_num = 1;
187 param.i_timebase_den = TIMEBASE;
188 param.i_keyint_max = 50; // About one second.
189 if (!use_separate_disk_params && global_flags.x264_speedcontrol) {
190 param.i_frame_reference = 16; // Because speedcontrol is never allowed to change this above what we set at start.
192 #if X264_BUILD >= 153
193 param.i_bitdepth = global_flags.bit_depth;
196 // NOTE: These should be in sync with the ones in quicksync_encoder.cpp (sps_rbsp()).
197 param.vui.i_vidformat = 5; // Unspecified.
198 param.vui.b_fullrange = 0;
199 param.vui.i_colorprim = 1; // BT.709.
200 param.vui.i_transfer = 13; // sRGB.
201 if (global_flags.ycbcr_rec709_coefficients) {
202 param.vui.i_colmatrix = 1; // BT.709.
204 param.vui.i_colmatrix = 6; // BT.601/SMPTE 170M.
207 const double crf = use_separate_disk_params ? global_flags.x264_separate_disk_crf : global_flags.x264_crf;
208 const int bitrate = use_separate_disk_params ? global_flags.x264_separate_disk_bitrate : global_flags.x264_bitrate;
210 param.rc.i_rc_method = X264_RC_CRF;
211 param.rc.f_rf_constant = crf;
213 param.rc.i_rc_method = X264_RC_ABR;
214 param.rc.i_bitrate = bitrate;
216 // If the user wants to cap the max rate, it is also reasonable
217 // to assume that they are fine with the stream constantly
218 // being around that rate even for very low-complexity content;
219 // the obvious and extreme example being a static black picture.
221 // One would think it's fine to have low-complexity content use
222 // less bitrate, but it seems to cause problems in practice;
223 // e.g. VLC seems to often drop the stream (similar to a buffer
224 // underrun) in such cases, but only when streaming from Nageru,
225 // not when reading a dump of the same stream from disk.
226 // I'm not 100% sure whether it's in VLC (possibly some buffering
227 // in the HTTP layer), in microhttpd or somewhere in Nageru itself,
228 // but it's a typical case of problems that can arise. Similarly,
229 // TCP's congestion control is not always fond of the rate staying
230 // low for a while and then rising quickly -- a variation on the same
233 // We solve this by simply asking x264 to fill in dummy bits
234 // in these cases, so that the bitrate stays reasonable constant.
235 // It's a waste of bandwidth, but it makes things go much more
236 // smoothly in these cases. (We don't do it if VBV control is off
237 // in general, not the least because it makes no sense and x264
238 // thus ignores the parameter.)
239 param.rc.b_filler = 1;
241 if (!use_separate_disk_params) {
242 update_vbv_settings(¶m);
245 // Occasionally players have problem with extremely low quantizers;
246 // be on the safe side. Shouldn't affect quality in any meaningful way.
247 param.rc.i_qp_min = 5;
249 const vector<string> &extra_param = use_separate_disk_params ? global_flags.x264_separate_disk_extra_param : global_flags.x264_extra_param;
250 for (const string &str : extra_param) {
251 const size_t pos = str.find(',');
252 if (pos == string::npos) {
253 if (dyn.x264_param_parse(¶m, str.c_str(), nullptr) != 0) {
254 fprintf(stderr, "ERROR: x264 rejected parameter '%s'\n", str.c_str());
257 const string key = str.substr(0, pos);
258 const string value = str.substr(pos + 1);
259 if (dyn.x264_param_parse(¶m, key.c_str(), value.c_str()) != 0) {
260 fprintf(stderr, "ERROR: x264 rejected parameter '%s' set to '%s'\n",
261 key.c_str(), value.c_str());
266 if (global_flags.bit_depth > 8) {
267 dyn.x264_param_apply_profile(¶m, "high10");
269 dyn.x264_param_apply_profile(¶m, "high");
272 param.b_repeat_headers = !wants_global_headers;
274 x264 = dyn.x264_encoder_open(¶m);
275 if (x264 == nullptr) {
276 fprintf(stderr, "ERROR: x264 initialization failed.\n");
280 if (!use_separate_disk_params && global_flags.x264_speedcontrol) {
281 speed_control.reset(new X264SpeedControl(x264, /*f_speed=*/1.0f, X264_QUEUE_LENGTH, /*f_buffer_init=*/1.0f));
284 if (wants_global_headers) {
288 dyn.x264_encoder_headers(x264, &nal, &num_nal);
290 for (int i = 0; i < num_nal; ++i) {
291 if (nal[i].i_type == NAL_SEI) {
292 // Don't put the SEI in extradata; make it part of the first frame instead.
293 buffered_sei += string((const char *)nal[i].p_payload, nal[i].i_payload);
295 global_headers += string((const char *)nal[i].p_payload, nal[i].i_payload);
301 void X264Encoder::encoder_thread_func()
303 if (nice(5) == -1) { // Note that x264 further nices some of its threads.
305 // No exit; it's not fatal.
307 pthread_setname_np(pthread_self(), "x264_encode");
309 x264_init_done = true;
316 // Wait for a queued frame, then dequeue it.
318 unique_lock<mutex> lock(mu);
319 queued_frames_nonempty.wait(lock, [this]() { return !queued_frames.empty() || should_quit; });
320 if (!queued_frames.empty()) {
321 qf = queued_frames.front();
329 if (use_separate_disk_params) {
330 metric_x264_disk_queued_frames = queued_frames.size();
332 metric_x264_queued_frames = queued_frames.size();
334 frames_left = !queued_frames.empty();
340 lock_guard<mutex> lock(mu);
341 free_frames.push(qf.data);
344 // We should quit only if the should_quit flag is set _and_ we have nothing
346 } while (!should_quit || frames_left || dyn.x264_encoder_delayed_frames(x264) > 0);
348 dyn.x264_encoder_close(x264);
351 void X264Encoder::encode_frame(X264Encoder::QueuedFrame qf)
353 x264_nal_t *nal = nullptr;
356 x264_picture_t *input_pic = nullptr;
359 dyn.x264_picture_init(&pic);
362 if (global_flags.bit_depth > 8) {
363 pic.img.i_csp = X264_CSP_NV12 | X264_CSP_HIGH_DEPTH;
365 pic.img.plane[0] = qf.data;
366 pic.img.i_stride[0] = global_flags.width * sizeof(uint16_t);
367 pic.img.plane[1] = qf.data + global_flags.width * global_flags.height * sizeof(uint16_t);
368 pic.img.i_stride[1] = global_flags.width / 2 * sizeof(uint32_t);
370 pic.img.i_csp = X264_CSP_NV12;
372 pic.img.plane[0] = qf.data;
373 pic.img.i_stride[0] = global_flags.width;
374 pic.img.plane[1] = qf.data + global_flags.width * global_flags.height;
375 pic.img.i_stride[1] = global_flags.width / 2 * sizeof(uint16_t);
377 pic.opaque = reinterpret_cast<void *>(intptr_t(qf.duration));
381 frames_being_encoded[qf.pts] = qf.received_ts;
384 unsigned new_rate = new_bitrate_kbit.load(); // Can be 0 for no change.
386 speed_control->set_config_override_function(bind(&speed_control_override_func, new_rate, qf.ycbcr_coefficients, _1));
389 dyn.x264_encoder_parameters(x264, ¶m);
390 speed_control_override_func(new_rate, qf.ycbcr_coefficients, ¶m);
391 dyn.x264_encoder_reconfig(x264, ¶m);
395 float queue_fill_ratio;
397 lock_guard<mutex> lock(mu);
398 queue_fill_ratio = float(free_frames.size()) / X264_QUEUE_LENGTH;
400 speed_control->before_frame(queue_fill_ratio, X264_QUEUE_LENGTH, 1e6 * qf.duration / TIMEBASE);
402 dyn.x264_encoder_encode(x264, &nal, &num_nal, input_pic, &pic);
404 speed_control->after_frame();
407 if (num_nal == 0) return;
409 if (use_separate_disk_params) {
410 if (IS_X264_TYPE_I(pic.i_type)) {
411 ++metric_x264_disk_output_frames_i;
412 } else if (IS_X264_TYPE_B(pic.i_type)) {
413 ++metric_x264_disk_output_frames_b;
415 ++metric_x264_disk_output_frames_p;
418 metric_x264_disk_crf.count_event(pic.prop.f_crf_avg);
420 if (IS_X264_TYPE_I(pic.i_type)) {
421 ++metric_x264_output_frames_i;
422 } else if (IS_X264_TYPE_B(pic.i_type)) {
423 ++metric_x264_output_frames_b;
425 ++metric_x264_output_frames_p;
428 metric_x264_crf.count_event(pic.prop.f_crf_avg);
431 if (frames_being_encoded.count(pic.i_pts)) {
432 ReceivedTimestamps received_ts = frames_being_encoded[pic.i_pts];
433 frames_being_encoded.erase(pic.i_pts);
435 static int frameno = 0;
436 print_latency("Current x264 latency (video inputs → network mux):",
437 received_ts, (pic.i_type == X264_TYPE_B || pic.i_type == X264_TYPE_BREF),
438 &frameno, &x264_latency_histogram);
443 // We really need one AVPacket for the entire frame, it seems,
444 // so combine it all.
445 size_t num_bytes = buffered_sei.size();
446 for (int i = 0; i < num_nal; ++i) {
447 num_bytes += nal[i].i_payload;
450 unique_ptr<uint8_t[]> data(new uint8_t[num_bytes]);
451 uint8_t *ptr = data.get();
453 if (!buffered_sei.empty()) {
454 memcpy(ptr, buffered_sei.data(), buffered_sei.size());
455 ptr += buffered_sei.size();
456 buffered_sei.clear();
458 for (int i = 0; i < num_nal; ++i) {
459 memcpy(ptr, nal[i].p_payload, nal[i].i_payload);
460 ptr += nal[i].i_payload;
464 memset(&pkt, 0, sizeof(pkt));
466 pkt.data = data.get();
467 pkt.size = num_bytes;
468 pkt.stream_index = 0;
469 if (pic.b_keyframe) {
470 pkt.flags = AV_PKT_FLAG_KEY;
474 pkt.duration = reinterpret_cast<intptr_t>(pic.opaque);
476 for (Mux *mux : muxes) {
477 mux->add_packet(pkt, pic.i_pts, pic.i_dts);
481 void X264Encoder::speed_control_override_func(unsigned bitrate_kbit, movit::YCbCrLumaCoefficients ycbcr_coefficients, x264_param_t *param)
483 if (bitrate_kbit != 0) {
484 param->rc.i_bitrate = bitrate_kbit;
485 update_vbv_settings(param);
488 if (ycbcr_coefficients == YCBCR_REC_709) {
489 param->vui.i_colmatrix = 1; // BT.709.
491 assert(ycbcr_coefficients == YCBCR_REC_601);
492 param->vui.i_colmatrix = 6; // BT.601/SMPTE 170M.