lavfi: add sine audio source.
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				| @ -10,6 +10,7 @@ version <next>: | |||||||
| - perms and aperms filters | - perms and aperms filters | ||||||
| - audio filtering support in ffplay | - audio filtering support in ffplay | ||||||
| - 10% faster aac encoding on x86 and MIPS | - 10% faster aac encoding on x86 and MIPS | ||||||
|  | - sine audio filter source | ||||||
| 
 | 
 | ||||||
| 
 | 
 | ||||||
| version 1.2: | version 1.2: | ||||||
|  | |||||||
| @ -1653,6 +1653,57 @@ ffplay -f lavfi flite=text='No more be grieved for which that thou hast done.' | |||||||
| For more information about libflite, check: | For more information about libflite, check: | ||||||
| @url{http://www.speech.cs.cmu.edu/flite/} | @url{http://www.speech.cs.cmu.edu/flite/} | ||||||
| 
 | 
 | ||||||
|  | @section sine | ||||||
|  | 
 | ||||||
|  | Generate an audio signal made of a sine wave with amplitude 1/8. | ||||||
|  | 
 | ||||||
|  | The audio signal is bit-exact. | ||||||
|  | 
 | ||||||
|  | It accepts a list of options in the form of @var{key}=@var{value} pairs | ||||||
|  | separated by ":". If the option name is omitted, the first option is the | ||||||
|  | frequency and the second option is the beep factor. | ||||||
|  | 
 | ||||||
|  | The supported options are: | ||||||
|  | 
 | ||||||
|  | @table @option | ||||||
|  | 
 | ||||||
|  | @item frequency, f | ||||||
|  | Set the carrier frequency. Default is 440 Hz. | ||||||
|  | 
 | ||||||
|  | @item beep_factor, b | ||||||
|  | Enable a periodic beep every second with frequency @var{beep_factor} times | ||||||
|  | the carrier frequency. Default is 0, meaning the beep is disabled. | ||||||
|  | 
 | ||||||
|  | @item sample_rate, s | ||||||
|  | Specify the sample rate, default is 44100. | ||||||
|  | 
 | ||||||
|  | @item duration, d | ||||||
|  | Specify the duration of the generated audio stream. | ||||||
|  | 
 | ||||||
|  | @item samples_per_frame | ||||||
|  | Set the number of samples per output frame, default is 1024. | ||||||
|  | @end table | ||||||
|  | 
 | ||||||
|  | @subsection Examples | ||||||
|  | 
 | ||||||
|  | @itemize | ||||||
|  | 
 | ||||||
|  | @item | ||||||
|  | Generate a simple 440 Hz sine wave: | ||||||
|  | @example | ||||||
|  | sine | ||||||
|  | @end example | ||||||
|  | 
 | ||||||
|  | @item | ||||||
|  | Generate a 220 Hz sine wave with a 880 Hz beep each second, for 5 seconds: | ||||||
|  | @example | ||||||
|  | sine=220:4:d=5 | ||||||
|  | sine=f=220:b=4:d=5 | ||||||
|  | sine=frequency=220:beep_factor=4:duration=5 | ||||||
|  | @end example | ||||||
|  | 
 | ||||||
|  | @end itemize | ||||||
|  | 
 | ||||||
| @c man end AUDIO SOURCES | @c man end AUDIO SOURCES | ||||||
| 
 | 
 | ||||||
| @chapter Audio Sinks | @chapter Audio Sinks | ||||||
|  | |||||||
| @ -90,6 +90,7 @@ OBJS-$(CONFIG_VOLUMEDETECT_FILTER)           += af_volumedetect.o | |||||||
| OBJS-$(CONFIG_AEVALSRC_FILTER)               += asrc_aevalsrc.o | OBJS-$(CONFIG_AEVALSRC_FILTER)               += asrc_aevalsrc.o | ||||||
| OBJS-$(CONFIG_ANULLSRC_FILTER)               += asrc_anullsrc.o | OBJS-$(CONFIG_ANULLSRC_FILTER)               += asrc_anullsrc.o | ||||||
| OBJS-$(CONFIG_FLITE_FILTER)                  += asrc_flite.o | OBJS-$(CONFIG_FLITE_FILTER)                  += asrc_flite.o | ||||||
|  | OBJS-$(CONFIG_SINE_FILTER)                   += asrc_sine.o | ||||||
| 
 | 
 | ||||||
| OBJS-$(CONFIG_ANULLSINK_FILTER)              += asink_anullsink.o | OBJS-$(CONFIG_ANULLSINK_FILTER)              += asink_anullsink.o | ||||||
| 
 | 
 | ||||||
|  | |||||||
| @ -86,6 +86,7 @@ void avfilter_register_all(void) | |||||||
|     REGISTER_FILTER(AEVALSRC,       aevalsrc,       asrc); |     REGISTER_FILTER(AEVALSRC,       aevalsrc,       asrc); | ||||||
|     REGISTER_FILTER(ANULLSRC,       anullsrc,       asrc); |     REGISTER_FILTER(ANULLSRC,       anullsrc,       asrc); | ||||||
|     REGISTER_FILTER(FLITE,          flite,          asrc); |     REGISTER_FILTER(FLITE,          flite,          asrc); | ||||||
|  |     REGISTER_FILTER(SINE,           sine,           asrc); | ||||||
| 
 | 
 | ||||||
|     REGISTER_FILTER(ANULLSINK,      anullsink,      asink); |     REGISTER_FILTER(ANULLSINK,      anullsink,      asink); | ||||||
| 
 | 
 | ||||||
|  | |||||||
							
								
								
									
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							| @ -0,0 +1,228 @@ | |||||||
|  | /*
 | ||||||
|  |  * Copyright (c) 2013 Nicolas George | ||||||
|  |  * | ||||||
|  |  * This file is part of FFmpeg. | ||||||
|  |  * | ||||||
|  |  * FFmpeg is free software; you can redistribute it and/or | ||||||
|  |  * modify it under the terms of the GNU Lesser General Public License | ||||||
|  |  * as published by the Free Software Foundation; either | ||||||
|  |  * version 2.1 of the License, or (at your option) any later version. | ||||||
|  |  * | ||||||
|  |  * FFmpeg is distributed in the hope that it will be useful, | ||||||
|  |  * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||||||
|  |  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | ||||||
|  |  * GNU Lesser General Public License for more details. | ||||||
|  |  * | ||||||
|  |  * You should have received a copy of the GNU Lesser General Public License | ||||||
|  |  * along with FFmpeg; if not, write to the Free Software Foundation, Inc., | ||||||
|  |  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||||||
|  |  */ | ||||||
|  | 
 | ||||||
|  | #include "libavutil/avassert.h" | ||||||
|  | #include "libavutil/channel_layout.h" | ||||||
|  | #include "libavutil/opt.h" | ||||||
|  | #include "audio.h" | ||||||
|  | #include "avfilter.h" | ||||||
|  | #include "internal.h" | ||||||
|  | 
 | ||||||
|  | typedef struct { | ||||||
|  |     const AVClass *class; | ||||||
|  |     double frequency; | ||||||
|  |     double beep_factor; | ||||||
|  |     int samples_per_frame; | ||||||
|  |     int sample_rate; | ||||||
|  |     int64_t duration; | ||||||
|  |     int16_t *sin; | ||||||
|  |     int64_t pts; | ||||||
|  |     uint32_t phi;  ///< current phase of the sine (2pi = 1<<32)
 | ||||||
|  |     uint32_t dphi; ///< phase increment between two samples
 | ||||||
|  |     unsigned beep_period; | ||||||
|  |     unsigned beep_index; | ||||||
|  |     unsigned beep_length; | ||||||
|  |     uint32_t phi_beep;  ///< current phase of the beep
 | ||||||
|  |     uint32_t dphi_beep; ///< phase increment of the beep
 | ||||||
|  | } SineContext; | ||||||
|  | 
 | ||||||
|  | #define CONTEXT SineContext | ||||||
|  | #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM | ||||||
|  | 
 | ||||||
|  | #define OPT_GENERIC(name, field, def, min, max, descr, type, deffield, ...) \ | ||||||
|  |     { name, descr, offsetof(CONTEXT, field), AV_OPT_TYPE_ ## type,          \ | ||||||
|  |       { .deffield = def }, min, max, FLAGS, __VA_ARGS__ } | ||||||
|  | 
 | ||||||
|  | #define OPT_INT(name, field, def, min, max, descr, ...) \ | ||||||
|  |     OPT_GENERIC(name, field, def, min, max, descr, INT, i64, __VA_ARGS__) | ||||||
|  | 
 | ||||||
|  | #define OPT_DBL(name, field, def, min, max, descr, ...) \ | ||||||
|  |     OPT_GENERIC(name, field, def, min, max, descr, DOUBLE, dbl, __VA_ARGS__) | ||||||
|  | 
 | ||||||
|  | #define OPT_DUR(name, field, def, min, max, descr, ...) \ | ||||||
|  |     OPT_GENERIC(name, field, def, min, max, descr, DURATION, str, __VA_ARGS__) | ||||||
|  | 
 | ||||||
|  | static const AVOption sine_options[] = { | ||||||
|  |     OPT_DBL("frequency",         frequency,            440, 0, INFINITY,  "set the sine frequency"), | ||||||
|  |     OPT_DBL("f",                 frequency,            440, 0, INFINITY,  "set the sine frequency"), | ||||||
|  |     OPT_DBL("beep_factor",       beep_factor,            0, 0, INFINITY,  "set the beep fequency factor"), | ||||||
|  |     OPT_DBL("b",                 beep_factor,            0, 0, INFINITY,  "set the beep fequency factor"), | ||||||
|  |     OPT_INT("sample_rate",       sample_rate,        44100, 1, INT_MAX,   "set the sample rate"), | ||||||
|  |     OPT_INT("r",                 sample_rate,        44100, 1, INT_MAX,   "set the sample rate"), | ||||||
|  |     OPT_DUR("duration",          duration,               0, 0, INT64_MAX, "set the audio duration"), | ||||||
|  |     OPT_DUR("d",                 duration,               0, 0, INT64_MAX, "set the audio duration"), | ||||||
|  |     OPT_INT("samples_per_frame", samples_per_frame,   1024, 0, INT_MAX,   "set the number of samples per frame"), | ||||||
|  |     {NULL}, | ||||||
|  | }; | ||||||
|  | 
 | ||||||
|  | AVFILTER_DEFINE_CLASS(sine); | ||||||
|  | 
 | ||||||
|  | #define LOG_PERIOD 15 | ||||||
|  | #define AMPLITUDE 4095 | ||||||
|  | #define AMPLITUDE_SHIFT 3 | ||||||
|  | 
 | ||||||
|  | static void make_sin_table(int16_t *sin) | ||||||
|  | { | ||||||
|  |     unsigned half_pi = 1 << (LOG_PERIOD - 2); | ||||||
|  |     unsigned ampls = AMPLITUDE << AMPLITUDE_SHIFT; | ||||||
|  |     uint64_t unit2 = (uint64_t)(ampls * ampls) << 32; | ||||||
|  |     unsigned step, i, c, s, k, new_k, n2; | ||||||
|  | 
 | ||||||
|  |     /* Principle: if u = exp(i*a1) and v = exp(i*a2), then
 | ||||||
|  |        exp(i*(a1+a2)/2) = (u+v) / length(u+v) */ | ||||||
|  |     sin[0] = 0; | ||||||
|  |     sin[half_pi] = ampls; | ||||||
|  |     for (step = half_pi; step > 1; step /= 2) { | ||||||
|  |         /* k = (1 << 16) * amplitude / length(u+v)
 | ||||||
|  |            In exact values, k is constant at a given step */ | ||||||
|  |         k = 0x10000; | ||||||
|  |         for (i = 0; i < half_pi / 2; i += step) { | ||||||
|  |             s = sin[i] + sin[i + step]; | ||||||
|  |             c = sin[half_pi - i] + sin[half_pi - i - step]; | ||||||
|  |             n2 = s * s + c * c; | ||||||
|  |             /* Newton's method to solve n² * k² = unit² */ | ||||||
|  |             while (1) { | ||||||
|  |                 new_k = (k + unit2 / ((uint64_t)k * n2) + 1) >> 1; | ||||||
|  |                 if (k == new_k) | ||||||
|  |                     break; | ||||||
|  |                 k = new_k; | ||||||
|  |             } | ||||||
|  |             sin[i + step / 2] = (k * s + 0x7FFF) >> 16; | ||||||
|  |             sin[half_pi - i - step / 2] = (k * c + 0x8000) >> 16; | ||||||
|  |         } | ||||||
|  |     } | ||||||
|  |     /* Unshift amplitude */ | ||||||
|  |     for (i = 0; i <= half_pi; i++) | ||||||
|  |         sin[i] = (sin[i] + (1 << (AMPLITUDE_SHIFT - 1))) >> AMPLITUDE_SHIFT; | ||||||
|  |     /* Use symmetries to fill the other three quarters */ | ||||||
|  |     for (i = 0; i < half_pi; i++) | ||||||
|  |         sin[half_pi * 2 - i] = sin[i]; | ||||||
|  |     for (i = 0; i < 2 * half_pi; i++) | ||||||
|  |         sin[i + 2 * half_pi] = -sin[i]; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static av_cold int init(AVFilterContext *ctx, const char *args) | ||||||
|  | { | ||||||
|  |     SineContext *sine = ctx->priv; | ||||||
|  |     static const char *shorthand[] = { "frequency", "beep_factor", NULL }; | ||||||
|  |     int ret; | ||||||
|  | 
 | ||||||
|  |     sine->class = &sine_class; | ||||||
|  |     av_opt_set_defaults(sine); | ||||||
|  | 
 | ||||||
|  |     if ((ret = av_opt_set_from_string(sine, args, shorthand, "=", ":")) < 0) | ||||||
|  |         return ret; | ||||||
|  |     if (!(sine->sin = av_malloc(sizeof(*sine->sin) << LOG_PERIOD))) | ||||||
|  |         return AVERROR(ENOMEM); | ||||||
|  |     sine->dphi = ldexp(sine->frequency, 32) / sine->sample_rate + 0.5; | ||||||
|  |     make_sin_table(sine->sin); | ||||||
|  | 
 | ||||||
|  |     if (sine->beep_factor) { | ||||||
|  |         sine->beep_period = sine->sample_rate; | ||||||
|  |         sine->beep_length = sine->beep_period / 25; | ||||||
|  |         sine->dphi_beep = ldexp(sine->beep_factor * sine->frequency, 32) / | ||||||
|  |                           sine->sample_rate + 0.5; | ||||||
|  |     } | ||||||
|  | 
 | ||||||
|  |     return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static av_cold void uninit(AVFilterContext *ctx) | ||||||
|  | { | ||||||
|  |     SineContext *sine = ctx->priv; | ||||||
|  | 
 | ||||||
|  |     av_freep(&sine->sin); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static av_cold int query_formats(AVFilterContext *ctx) | ||||||
|  | { | ||||||
|  |     SineContext *sine = ctx->priv; | ||||||
|  |     static const int64_t chlayouts[] = { AV_CH_LAYOUT_MONO, -1 }; | ||||||
|  |     int sample_rates[] = { sine->sample_rate, -1 }; | ||||||
|  |     static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, | ||||||
|  |                                                        AV_SAMPLE_FMT_NONE }; | ||||||
|  | 
 | ||||||
|  |     ff_set_common_formats (ctx, ff_make_format_list(sample_fmts)); | ||||||
|  |     ff_set_common_channel_layouts(ctx, avfilter_make_format64_list(chlayouts)); | ||||||
|  |     ff_set_common_samplerates(ctx, ff_make_format_list(sample_rates)); | ||||||
|  |     return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static av_cold int config_props(AVFilterLink *outlink) | ||||||
|  | { | ||||||
|  |     SineContext *sine = outlink->src->priv; | ||||||
|  |     sine->duration = av_rescale(sine->duration, sine->sample_rate, AV_TIME_BASE); | ||||||
|  |     return 0; | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static int request_frame(AVFilterLink *outlink) | ||||||
|  | { | ||||||
|  |     SineContext *sine = outlink->src->priv; | ||||||
|  |     AVFrame *frame; | ||||||
|  |     int i, nb_samples = sine->samples_per_frame; | ||||||
|  |     int16_t *samples; | ||||||
|  | 
 | ||||||
|  |     if (sine->duration) { | ||||||
|  |         nb_samples = FFMIN(nb_samples, sine->duration - sine->pts); | ||||||
|  |         av_assert1(nb_samples >= 0); | ||||||
|  |         if (!nb_samples) | ||||||
|  |             return AVERROR_EOF; | ||||||
|  |     } | ||||||
|  |     if (!(frame = ff_get_audio_buffer(outlink, nb_samples))) | ||||||
|  |         return AVERROR(ENOMEM); | ||||||
|  |     samples = (int16_t *)frame->data[0]; | ||||||
|  | 
 | ||||||
|  |     for (i = 0; i < nb_samples; i++) { | ||||||
|  |         samples[i] = sine->sin[sine->phi >> (32 - LOG_PERIOD)]; | ||||||
|  |         sine->phi += sine->dphi; | ||||||
|  |         if (sine->beep_index < sine->beep_length) { | ||||||
|  |             samples[i] += sine->sin[sine->phi_beep >> (32 - LOG_PERIOD)] << 1; | ||||||
|  |             sine->phi_beep += sine->dphi_beep; | ||||||
|  |         } | ||||||
|  |         if (++sine->beep_index == sine->beep_period) | ||||||
|  |             sine->beep_index = 0; | ||||||
|  |     } | ||||||
|  | 
 | ||||||
|  |     frame->pts = sine->pts; | ||||||
|  |     sine->pts += nb_samples; | ||||||
|  |     return ff_filter_frame(outlink, frame); | ||||||
|  | } | ||||||
|  | 
 | ||||||
|  | static const AVFilterPad sine_outputs[] = { | ||||||
|  |     { | ||||||
|  |         .name          = "default", | ||||||
|  |         .type          = AVMEDIA_TYPE_AUDIO, | ||||||
|  |         .request_frame = request_frame, | ||||||
|  |         .config_props  = config_props, | ||||||
|  |     }, | ||||||
|  |     { NULL } | ||||||
|  | }; | ||||||
|  | 
 | ||||||
|  | AVFilter avfilter_asrc_sine = { | ||||||
|  |     .name          = "sine", | ||||||
|  |     .description   = NULL_IF_CONFIG_SMALL("Generate sine wave audio signal."), | ||||||
|  |     .query_formats = query_formats, | ||||||
|  |     .init          = init, | ||||||
|  |     .uninit        = uninit, | ||||||
|  |     .priv_size     = sizeof(SineContext), | ||||||
|  |     .inputs        = NULL, | ||||||
|  |     .outputs       = sine_outputs, | ||||||
|  |     .priv_class    = &sine_class, | ||||||
|  | }; | ||||||
| @ -29,8 +29,8 @@ | |||||||
| #include "libavutil/avutil.h" | #include "libavutil/avutil.h" | ||||||
| 
 | 
 | ||||||
| #define LIBAVFILTER_VERSION_MAJOR  3 | #define LIBAVFILTER_VERSION_MAJOR  3 | ||||||
| #define LIBAVFILTER_VERSION_MINOR  47 | #define LIBAVFILTER_VERSION_MINOR  48 | ||||||
| #define LIBAVFILTER_VERSION_MICRO 104 | #define LIBAVFILTER_VERSION_MICRO 100 | ||||||
| 
 | 
 | ||||||
| #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ | #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ | ||||||
|                                                LIBAVFILTER_VERSION_MINOR, \ |                                                LIBAVFILTER_VERSION_MINOR, \ | ||||||
|  | |||||||
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