2 * Copyright (c) 2001-2010 Krzysztof Foltman, Markus Schmidt, Thor Harald Johansen and others
3 * Copyright (c) 2015 Paul B Mahol
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/avstring.h"
24 #include "libavutil/ffmath.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/parseutils.h"
31 #define FILTER_ORDER 4
40 typedef struct FoSection {
41 double a0, a1, a2, a3, a4;
42 double b0, b1, b2, b3, b4;
48 typedef struct EqualizatorFilter {
60 typedef struct AudioNEqualizerContext {
71 EqualizatorFilter *filters;
73 } AudioNEqualizerContext;
75 #define OFFSET(x) offsetof(AudioNEqualizerContext, x)
76 #define A AV_OPT_FLAG_AUDIO_PARAM
77 #define V AV_OPT_FLAG_VIDEO_PARAM
78 #define F AV_OPT_FLAG_FILTERING_PARAM
80 static const AVOption anequalizer_options[] = {
81 { "params", NULL, OFFSET(args), AV_OPT_TYPE_STRING, {.str=""}, 0, 0, A|F },
82 { "curves", "draw frequency response curves", OFFSET(draw_curves), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, V|F },
83 { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "hd720"}, 0, 0, V|F },
84 { "mgain", "set max gain", OFFSET(mag), AV_OPT_TYPE_DOUBLE, {.dbl=60}, -900, 900, V|F },
85 { "fscale", "set frequency scale", OFFSET(fscale), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, V|F, "fscale" },
86 { "lin", "linear", 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, V|F, "fscale" },
87 { "log", "logarithmic", 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, V|F, "fscale" },
88 { "colors", "set channels curves colors", OFFSET(colors), AV_OPT_TYPE_STRING, {.str = "red|green|blue|yellow|orange|lime|pink|magenta|brown" }, 0, 0, V|F },
92 AVFILTER_DEFINE_CLASS(anequalizer);
94 static void draw_curves(AVFilterContext *ctx, AVFilterLink *inlink, AVFrame *out)
96 AudioNEqualizerContext *s = ctx->priv;
97 char *colors, *color, *saveptr = NULL;
100 colors = av_strdup(s->colors);
104 memset(out->data[0], 0, s->h * out->linesize[0]);
106 for (ch = 0; ch < inlink->channels; ch++) {
107 uint8_t fg[4] = { 0xff, 0xff, 0xff, 0xff };
111 color = av_strtok(ch == 0 ? colors : NULL, " |", &saveptr);
113 av_parse_color(fg, color, -1, ctx);
115 for (f = 0; f < s->w; f++) {
116 double zr, zi, zr2, zi2;
122 w = M_PI * (s->fscale ? pow(s->w - 1, f / s->w) : f) / (s->w - 1);
128 for (n = 0; n < s->nb_filters; n++) {
129 if (s->filters[n].channel != ch ||
130 s->filters[n].ignore)
133 for (i = 0; i < FILTER_ORDER / 2; i++) {
134 FoSection *S = &s->filters[n].section[i];
136 /* H *= (((((S->b4 * z + S->b3) * z + S->b2) * z + S->b1) * z + S->b0) /
137 ((((S->a4 * z + S->a3) * z + S->a2) * z + S->a1) * z + S->a0)); */
139 Hr = S->b4*(1-8*zr2*zi2) + S->b2*(zr2-zi2) + zr*(S->b1+S->b3*(zr2-3*zi2))+ S->b0;
140 Hi = zi*(S->b3*(3*zr2-zi2) + S->b1 + 2*zr*(2*S->b4*(zr2-zi2) + S->b2));
141 Hmag *= hypot(Hr, Hi);
142 Hr = S->a4*(1-8*zr2*zi2) + S->a2*(zr2-zi2) + zr*(S->a1+S->a3*(zr2-3*zi2))+ S->a0;
143 Hi = zi*(S->a3*(3*zr2-zi2) + S->a1 + 2*zr*(2*S->a4*(zr2-zi2) + S->a2));
144 Hmag /= hypot(Hr, Hi);
148 v = av_clip((1. + -20 * log10(Hmag) / s->mag) * s->h / 2, 0, s->h - 1);
153 for (y = v; y <= prev_v; y++)
154 AV_WL32(out->data[0] + y * out->linesize[0] + x * 4, AV_RL32(fg));
156 for (y = prev_v; y <= v; y++)
157 AV_WL32(out->data[0] + y * out->linesize[0] + x * 4, AV_RL32(fg));
167 static int config_video(AVFilterLink *outlink)
169 AVFilterContext *ctx = outlink->src;
170 AudioNEqualizerContext *s = ctx->priv;
171 AVFilterLink *inlink = ctx->inputs[0];
177 av_frame_free(&s->video);
178 s->video = out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
180 return AVERROR(ENOMEM);
181 outlink->sample_aspect_ratio = (AVRational){1,1};
183 draw_curves(ctx, inlink, out);
188 static av_cold int init(AVFilterContext *ctx)
190 AudioNEqualizerContext *s = ctx->priv;
191 AVFilterPad pad, vpad;
196 .type = AVMEDIA_TYPE_AUDIO,
199 ret = ff_insert_outpad(ctx, 0, &pad);
203 if (s->draw_curves) {
204 vpad = (AVFilterPad){
206 .type = AVMEDIA_TYPE_VIDEO,
207 .config_props = config_video,
209 ret = ff_insert_outpad(ctx, 1, &vpad);
217 static int query_formats(AVFilterContext *ctx)
219 AVFilterLink *inlink = ctx->inputs[0];
220 AVFilterLink *outlink = ctx->outputs[0];
221 AudioNEqualizerContext *s = ctx->priv;
222 AVFilterFormats *formats;
223 AVFilterChannelLayouts *layouts;
224 static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE };
225 static const enum AVSampleFormat sample_fmts[] = {
231 if (s->draw_curves) {
232 AVFilterLink *videolink = ctx->outputs[1];
233 formats = ff_make_format_list(pix_fmts);
234 if ((ret = ff_formats_ref(formats, &videolink->incfg.formats)) < 0)
238 formats = ff_make_format_list(sample_fmts);
239 if ((ret = ff_formats_ref(formats, &inlink->outcfg.formats)) < 0 ||
240 (ret = ff_formats_ref(formats, &outlink->incfg.formats)) < 0)
243 layouts = ff_all_channel_counts();
244 if ((ret = ff_channel_layouts_ref(layouts, &inlink->outcfg.channel_layouts)) < 0 ||
245 (ret = ff_channel_layouts_ref(layouts, &outlink->incfg.channel_layouts)) < 0)
248 formats = ff_all_samplerates();
249 if ((ret = ff_formats_ref(formats, &inlink->outcfg.samplerates)) < 0 ||
250 (ret = ff_formats_ref(formats, &outlink->incfg.samplerates)) < 0)
256 static av_cold void uninit(AVFilterContext *ctx)
258 AudioNEqualizerContext *s = ctx->priv;
260 av_frame_free(&s->video);
261 av_freep(&s->filters);
266 static void butterworth_fo_section(FoSection *S, double beta,
267 double si, double g, double g0,
270 if (c0 == 1 || c0 == -1) {
271 S->b0 = (g*g*beta*beta + 2*g*g0*si*beta + g0*g0)/D;
272 S->b1 = 2*c0*(g*g*beta*beta - g0*g0)/D;
273 S->b2 = (g*g*beta*beta - 2*g0*g*beta*si + g0*g0)/D;
278 S->a1 = 2*c0*(beta*beta - 1)/D;
279 S->a2 = (beta*beta - 2*beta*si + 1)/D;
283 S->b0 = (g*g*beta*beta + 2*g*g0*si*beta + g0*g0)/D;
284 S->b1 = -4*c0*(g0*g0 + g*g0*si*beta)/D;
285 S->b2 = 2*(g0*g0*(1 + 2*c0*c0) - g*g*beta*beta)/D;
286 S->b3 = -4*c0*(g0*g0 - g*g0*si*beta)/D;
287 S->b4 = (g*g*beta*beta - 2*g*g0*si*beta + g0*g0)/D;
290 S->a1 = -4*c0*(1 + si*beta)/D;
291 S->a2 = 2*(1 + 2*c0*c0 - beta*beta)/D;
292 S->a3 = -4*c0*(1 - si*beta)/D;
293 S->a4 = (beta*beta - 2*si*beta + 1)/D;
297 static void butterworth_bp_filter(EqualizatorFilter *f,
298 int N, double w0, double wb,
299 double G, double Gb, double G0)
301 double g, c0, g0, beta;
307 if (G == 0 && G0 == 0) {
308 f->section[0].a0 = 1;
309 f->section[0].b0 = 1;
310 f->section[1].a0 = 1;
311 f->section[1].b0 = 1;
316 Gb = ff_exp10(Gb/20);
317 G0 = ff_exp10(G0/20);
319 epsilon = sqrt((G * G - Gb * Gb) / (Gb * Gb - G0 * G0));
321 g0 = pow(G0, 1.0 / N);
322 beta = pow(epsilon, -1.0 / N) * tan(wb/2);
325 for (i = 1; i <= L; i++) {
326 double ui = (2.0 * i - 1) / N;
327 double si = sin(M_PI * ui / 2.0);
328 double Di = beta * beta + 2 * si * beta + 1;
330 butterworth_fo_section(&f->section[i - 1], beta, si, g, g0, Di, c0);
334 static void chebyshev1_fo_section(FoSection *S, double a,
335 double c, double tetta_b,
336 double g0, double si, double b,
339 if (c0 == 1 || c0 == -1) {
340 S->b0 = (tetta_b*tetta_b*(b*b+g0*g0*c*c) + 2*g0*b*si*tetta_b*tetta_b + g0*g0)/D;
341 S->b1 = 2*c0*(tetta_b*tetta_b*(b*b+g0*g0*c*c) - g0*g0)/D;
342 S->b2 = (tetta_b*tetta_b*(b*b+g0*g0*c*c) - 2*g0*b*si*tetta_b + g0*g0)/D;
347 S->a1 = 2*c0*(tetta_b*tetta_b*(a*a+c*c) - 1)/D;
348 S->a2 = (tetta_b*tetta_b*(a*a+c*c) - 2*a*si*tetta_b + 1)/D;
352 S->b0 = ((b*b + g0*g0*c*c)*tetta_b*tetta_b + 2*g0*b*si*tetta_b + g0*g0)/D;
353 S->b1 = -4*c0*(g0*g0 + g0*b*si*tetta_b)/D;
354 S->b2 = 2*(g0*g0*(1 + 2*c0*c0) - (b*b + g0*g0*c*c)*tetta_b*tetta_b)/D;
355 S->b3 = -4*c0*(g0*g0 - g0*b*si*tetta_b)/D;
356 S->b4 = ((b*b + g0*g0*c*c)*tetta_b*tetta_b - 2*g0*b*si*tetta_b + g0*g0)/D;
359 S->a1 = -4*c0*(1 + a*si*tetta_b)/D;
360 S->a2 = 2*(1 + 2*c0*c0 - (a*a + c*c)*tetta_b*tetta_b)/D;
361 S->a3 = -4*c0*(1 - a*si*tetta_b)/D;
362 S->a4 = ((a*a + c*c)*tetta_b*tetta_b - 2*a*si*tetta_b + 1)/D;
366 static void chebyshev1_bp_filter(EqualizatorFilter *f,
367 int N, double w0, double wb,
368 double G, double Gb, double G0)
370 double a, b, c0, g0, alfa, beta, tetta_b;
376 if (G == 0 && G0 == 0) {
377 f->section[0].a0 = 1;
378 f->section[0].b0 = 1;
379 f->section[1].a0 = 1;
380 f->section[1].b0 = 1;
385 Gb = ff_exp10(Gb/20);
386 G0 = ff_exp10(G0/20);
388 epsilon = sqrt((G*G - Gb*Gb) / (Gb*Gb - G0*G0));
390 alfa = pow(1.0/epsilon + sqrt(1 + 1/(epsilon*epsilon)), 1.0/N);
391 beta = pow(G/epsilon + Gb * sqrt(1 + 1/(epsilon*epsilon)), 1.0/N);
392 a = 0.5 * (alfa - 1.0/alfa);
393 b = 0.5 * (beta - g0*g0*(1/beta));
397 for (i = 1; i <= L; i++) {
398 double ui = (2.0*i-1.0)/N;
399 double ci = cos(M_PI*ui/2.0);
400 double si = sin(M_PI*ui/2.0);
401 double Di = (a*a + ci*ci)*tetta_b*tetta_b + 2.0*a*si*tetta_b + 1;
403 chebyshev1_fo_section(&f->section[i - 1], a, ci, tetta_b, g0, si, b, Di, c0);
407 static void chebyshev2_fo_section(FoSection *S, double a,
408 double c, double tetta_b,
409 double g, double si, double b,
412 if (c0 == 1 || c0 == -1) {
413 S->b0 = (g*g*tetta_b*tetta_b + 2*tetta_b*g*b*si + b*b + g*g*c*c)/D;
414 S->b1 = 2*c0*(g*g*tetta_b*tetta_b - b*b - g*g*c*c)/D;
415 S->b2 = (g*g*tetta_b*tetta_b - 2*tetta_b*g*b*si + b*b + g*g*c*c)/D;
420 S->a1 = 2*c0*(tetta_b*tetta_b - a*a - c*c)/D;
421 S->a2 = (tetta_b*tetta_b - 2*tetta_b*a*si + a*a + c*c)/D;
425 S->b0 = (g*g*tetta_b*tetta_b + 2*g*b*si*tetta_b + b*b + g*g*c*c)/D;
426 S->b1 = -4*c0*(b*b + g*g*c*c + g*b*si*tetta_b)/D;
427 S->b2 = 2*((b*b + g*g*c*c)*(1 + 2*c0*c0) - g*g*tetta_b*tetta_b)/D;
428 S->b3 = -4*c0*(b*b + g*g*c*c - g*b*si*tetta_b)/D;
429 S->b4 = (g*g*tetta_b*tetta_b - 2*g*b*si*tetta_b + b*b + g*g*c*c)/D;
432 S->a1 = -4*c0*(a*a + c*c + a*si*tetta_b)/D;
433 S->a2 = 2*((a*a + c*c)*(1 + 2*c0*c0) - tetta_b*tetta_b)/D;
434 S->a3 = -4*c0*(a*a + c*c - a*si*tetta_b)/D;
435 S->a4 = (tetta_b*tetta_b - 2*a*si*tetta_b + a*a + c*c)/D;
439 static void chebyshev2_bp_filter(EqualizatorFilter *f,
440 int N, double w0, double wb,
441 double G, double Gb, double G0)
443 double a, b, c0, tetta_b;
444 double epsilon, g, eu, ew;
449 if (G == 0 && G0 == 0) {
450 f->section[0].a0 = 1;
451 f->section[0].b0 = 1;
452 f->section[1].a0 = 1;
453 f->section[1].b0 = 1;
458 Gb = ff_exp10(Gb/20);
459 G0 = ff_exp10(G0/20);
461 epsilon = sqrt((G*G - Gb*Gb) / (Gb*Gb - G0*G0));
463 eu = pow(epsilon + sqrt(1 + epsilon*epsilon), 1.0/N);
464 ew = pow(G0*epsilon + Gb*sqrt(1 + epsilon*epsilon), 1.0/N);
465 a = (eu - 1.0/eu)/2.0;
466 b = (ew - g*g/ew)/2.0;
470 for (i = 1; i <= L; i++) {
471 double ui = (2.0 * i - 1.0)/N;
472 double ci = cos(M_PI * ui / 2.0);
473 double si = sin(M_PI * ui / 2.0);
474 double Di = tetta_b*tetta_b + 2*a*si*tetta_b + a*a + ci*ci;
476 chebyshev2_fo_section(&f->section[i - 1], a, ci, tetta_b, g, si, b, Di, c0);
480 static double butterworth_compute_bw_gain_db(double gain)
486 else if(gain > -6 && gain < 6)
487 bw_gain = gain * 0.5;
494 static double chebyshev1_compute_bw_gain_db(double gain)
500 else if(gain > -6 && gain < 6)
501 bw_gain = gain * 0.9;
508 static double chebyshev2_compute_bw_gain_db(double gain)
514 else if(gain > -6 && gain < 6)
515 bw_gain = gain * 0.3;
522 static inline double hz_2_rad(double x, double fs)
524 return 2 * M_PI * x / fs;
527 static void equalizer(EqualizatorFilter *f, double sample_rate)
529 double w0 = hz_2_rad(f->freq, sample_rate);
530 double wb = hz_2_rad(f->width, sample_rate);
535 bw_gain = butterworth_compute_bw_gain_db(f->gain);
536 butterworth_bp_filter(f, FILTER_ORDER, w0, wb, f->gain, bw_gain, 0);
539 bw_gain = chebyshev1_compute_bw_gain_db(f->gain);
540 chebyshev1_bp_filter(f, FILTER_ORDER, w0, wb, f->gain, bw_gain, 0);
543 bw_gain = chebyshev2_compute_bw_gain_db(f->gain);
544 chebyshev2_bp_filter(f, FILTER_ORDER, w0, wb, f->gain, bw_gain, 0);
550 static int add_filter(AudioNEqualizerContext *s, AVFilterLink *inlink)
552 equalizer(&s->filters[s->nb_filters], inlink->sample_rate);
553 if (s->nb_filters >= s->nb_allocated - 1) {
554 EqualizatorFilter *filters;
556 filters = av_calloc(s->nb_allocated, 2 * sizeof(*s->filters));
558 return AVERROR(ENOMEM);
559 memcpy(filters, s->filters, sizeof(*s->filters) * s->nb_allocated);
561 s->filters = filters;
562 s->nb_allocated *= 2;
569 static int config_input(AVFilterLink *inlink)
571 AVFilterContext *ctx = inlink->dst;
572 AudioNEqualizerContext *s = ctx->priv;
573 char *args = av_strdup(s->args);
574 char *saveptr = NULL;
578 return AVERROR(ENOMEM);
580 s->nb_allocated = 32 * inlink->channels;
581 s->filters = av_calloc(inlink->channels, 32 * sizeof(*s->filters));
585 return AVERROR(ENOMEM);
589 char *arg = av_strtok(s->nb_filters == 0 ? args : NULL, "|", &saveptr);
594 s->filters[s->nb_filters].type = 0;
595 if (sscanf(arg, "c%d f=%lf w=%lf g=%lf t=%d", &s->filters[s->nb_filters].channel,
596 &s->filters[s->nb_filters].freq,
597 &s->filters[s->nb_filters].width,
598 &s->filters[s->nb_filters].gain,
599 &s->filters[s->nb_filters].type) != 5 &&
600 sscanf(arg, "c%d f=%lf w=%lf g=%lf", &s->filters[s->nb_filters].channel,
601 &s->filters[s->nb_filters].freq,
602 &s->filters[s->nb_filters].width,
603 &s->filters[s->nb_filters].gain) != 4 ) {
605 return AVERROR(EINVAL);
608 if (s->filters[s->nb_filters].freq < 0 ||
609 s->filters[s->nb_filters].freq > inlink->sample_rate / 2.0)
610 s->filters[s->nb_filters].ignore = 1;
612 if (s->filters[s->nb_filters].channel < 0 ||
613 s->filters[s->nb_filters].channel >= inlink->channels)
614 s->filters[s->nb_filters].ignore = 1;
616 s->filters[s->nb_filters].type = av_clip(s->filters[s->nb_filters].type, 0, NB_TYPES - 1);
617 ret = add_filter(s, inlink);
627 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
628 char *res, int res_len, int flags)
630 AudioNEqualizerContext *s = ctx->priv;
631 AVFilterLink *inlink = ctx->inputs[0];
632 int ret = AVERROR(ENOSYS);
634 if (!strcmp(cmd, "change")) {
635 double freq, width, gain;
638 if (sscanf(args, "%d|f=%lf|w=%lf|g=%lf", &filter, &freq, &width, &gain) != 4)
639 return AVERROR(EINVAL);
641 if (filter < 0 || filter >= s->nb_filters)
642 return AVERROR(EINVAL);
644 if (freq < 0 || freq > inlink->sample_rate / 2.0)
645 return AVERROR(EINVAL);
647 s->filters[filter].freq = freq;
648 s->filters[filter].width = width;
649 s->filters[filter].gain = gain;
650 equalizer(&s->filters[filter], inlink->sample_rate);
652 draw_curves(ctx, inlink, s->video);
660 static inline double section_process(FoSection *S, double in)
665 out+= S->b1 * S->num[0] - S->denum[0] * S->a1;
666 out+= S->b2 * S->num[1] - S->denum[1] * S->a2;
667 out+= S->b3 * S->num[2] - S->denum[2] * S->a3;
668 out+= S->b4 * S->num[3] - S->denum[3] * S->a4;
670 S->num[3] = S->num[2];
671 S->num[2] = S->num[1];
672 S->num[1] = S->num[0];
675 S->denum[3] = S->denum[2];
676 S->denum[2] = S->denum[1];
677 S->denum[1] = S->denum[0];
683 static double process_sample(FoSection *s1, double in)
688 for (i = 0; i < FILTER_ORDER / 2; i++) {
689 p1 = section_process(&s1[i], p0);
696 static int filter_channels(AVFilterContext *ctx, void *arg,
697 int jobnr, int nb_jobs)
699 AudioNEqualizerContext *s = ctx->priv;
701 const int start = (buf->channels * jobnr) / nb_jobs;
702 const int end = (buf->channels * (jobnr+1)) / nb_jobs;
704 for (int i = 0; i < s->nb_filters; i++) {
705 EqualizatorFilter *f = &s->filters[i];
708 if (f->gain == 0. || f->ignore)
710 if (f->channel < start ||
714 bptr = (double *)buf->extended_data[f->channel];
715 for (int n = 0; n < buf->nb_samples; n++) {
716 double sample = bptr[n];
718 sample = process_sample(f->section, sample);
726 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
728 AVFilterContext *ctx = inlink->dst;
729 AudioNEqualizerContext *s = ctx->priv;
730 AVFilterLink *outlink = ctx->outputs[0];
732 if (!ctx->is_disabled)
733 ctx->internal->execute(ctx, filter_channels, buf, NULL, FFMIN(inlink->channels,
734 ff_filter_get_nb_threads(ctx)));
736 if (s->draw_curves) {
739 const int64_t pts = buf->pts +
740 av_rescale_q(buf->nb_samples, (AVRational){ 1, inlink->sample_rate },
745 clone = av_frame_clone(s->video);
747 return AVERROR(ENOMEM);
748 ret = ff_filter_frame(ctx->outputs[1], clone);
753 return ff_filter_frame(outlink, buf);
756 static const AVFilterPad inputs[] = {
759 .type = AVMEDIA_TYPE_AUDIO,
760 .config_props = config_input,
761 .filter_frame = filter_frame,
767 const AVFilter ff_af_anequalizer = {
768 .name = "anequalizer",
769 .description = NULL_IF_CONFIG_SMALL("Apply high-order audio parametric multi band equalizer."),
770 .priv_size = sizeof(AudioNEqualizerContext),
771 .priv_class = &anequalizer_class,
774 .query_formats = query_formats,
777 .process_command = process_command,
778 .flags = AVFILTER_FLAG_DYNAMIC_OUTPUTS |
779 AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL |
780 AVFILTER_FLAG_SLICE_THREADS,