[FFmpeg-devel] GSoC 2020:Audio tones source filter
apk120
ashutoshp012345 at gmail.com
Sat Mar 14 14:16:00 EET 2020
Audio tones source filter to generate random audio tones using fluidsynth
diff --git a/Makefile b/Makefile
index 45a22b0cb3..44cf1b5710 100644
--- a/Makefile
+++ b/Makefile
@@ -111,7 +111,7 @@ else
endif
%$(PROGSSUF)_g$(EXESUF): $(FF_DEP_LIBS)
- $(LD) $(LDFLAGS) $(LDEXEFLAGS) $(LD_O) $(OBJS-$*) $(FF_EXTRALIBS)
+ $(LD) $(LDFLAGS) $(LDEXEFLAGS) $(LD_O) $(OBJS-$*) $(FF_EXTRALIBS) -lfluidsynth
VERSION_SH = $(SRC_PATH)/ffbuild/version.sh
GIT_LOG = $(SRC_PATH)/.git/logs/HEAD
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 750412da6b..b1f0c4be35 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -151,6 +151,7 @@ OBJS-$(CONFIG_FLITE_FILTER) += asrc_flite.o
OBJS-$(CONFIG_HILBERT_FILTER) += asrc_hilbert.o
OBJS-$(CONFIG_SINC_FILTER) += asrc_sinc.o
OBJS-$(CONFIG_SINE_FILTER) += asrc_sine.o
+OBJS-$(CONFIG_ATONE_FILTER) += asrc_atone.o
OBJS-$(CONFIG_ANULLSINK_FILTER) += asink_anullsink.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 501e5d041b..4d3efc7e15 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -145,6 +145,7 @@ extern AVFilter ff_asrc_flite;
extern AVFilter ff_asrc_hilbert;
extern AVFilter ff_asrc_sinc;
extern AVFilter ff_asrc_sine;
+extern AVFilter ff_asrc_atone;
extern AVFilter ff_asink_anullsink;
diff --git a/libavfilter/asrc_atone.c b/libavfilter/asrc_atone.c
new file mode 100644
index 0000000000..e3703f5e4b
--- /dev/null
+++ b/libavfilter/asrc_atone.c
@@ -0,0 +1,244 @@
+/*
+ * 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 <float.h>
+#include <stdio.h>
+#include <string.h>
+#include <fluidsynth.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "libavutil/avassert.h"
+#include "libavutil/channel_layout.h"
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "libavutil/lfg.h"
+#include "libavutil/random_seed.h"
+#include "audio.h"
+#include "avfilter.h"
+#include "internal.h"
+
+typedef struct AtoneContext
+{
+ const AVClass* class;
+ int64_t duration;
+ int nb_samples;
+ int sample_rate;
+ int64_t pts;
+ int infinite;
+
+ fluid_settings_t* settings;
+ fluid_synth_t* synth;
+ char* sfont; ///< soundfont file
+ int sfont_id;
+ int midi_chan; ///< midi channel number
+ int velocity; ///< velocity of key
+ int changerate; ///< get the frequency of changing tones
+ float* left; ///< store the left buffer
+ float* right; ///< store the right buffer
+ AVLFG key;
+}AtoneContext;
+
+#define CONTEXT AtoneContext
+#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_DUR(name, field, def, min, max, descr, ...) \
+ OPT_GENERIC(name, field, def, min, max, descr, DURATION, str, __VA_ARGS__)
+
+#define OPT_STR(name, field, def, min, max, descr, ...) \
+ OPT_GENERIC(name, field, def, min, max, descr, STRING, str, __VA_ARGS__)
+
+static const AVOption atone_options[] = {
+ OPT_INT("velocity", velocity, 80, 0, INT_MAX, "set the velocity of key press",),
+ OPT_INT("v", velocity, 80, 0, INT_MAX, "set the velocity of key press",),
+ 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_STR("sfont", sfont, "/usr/share/sounds/sf2/FluidR3_GM.sf2", 0, 0, "set the soundfont file",),
+ OPT_INT("samples_per_frame", nb_samples, 1024, 0, INT_MAX, "set the number of samples per frame",),
+ OPT_INT("MIDI channel", midi_chan, 0, 0, 16, "set the MIDI Channel",),
+ OPT_INT("Tone Change interval",changerate, 20, 1, INT_MAX, "set the random tone change interval",),
+ {NULL}
+};
+
+AVFILTER_DEFINE_CLASS(atone);
+
+static av_cold int init(AVFilterContext *ctx)
+{
+ AtoneContext *s = ctx->priv;
+ /*Initialise the fluidsynth settings object followed by synthesizer*/
+ s->settings = new_fluid_settings();
+ if (s->settings== NULL){
+ av_log(s, AV_LOG_ERROR, "Failed to create the fluidsynth settings");
+ return AVERROR_EXTERNAL;
+ }
+
+ s->synth = new_fluid_synth(s->settings);
+ if (s->synth== NULL){
+ av_log(s, AV_LOG_ERROR, "Failed to create the fluidsynth synth");
+ return AVERROR_EXTERNAL;
+ }
+
+ s->sfont_id= fluid_synth_sfload(s->synth, s->sfont, 1);
+ if(s->sfont_id== FLUID_FAILED){
+ av_log(s, AV_LOG_ERROR, "Loading the Soundfont Failed");
+ return AVERROR_EXTERNAL;
+ }
+
+ if (!(s->left = av_malloc(sizeof(*s->left)*(s->nb_samples))))
+ return AVERROR(ENOMEM);
+
+ if (!(s->right = av_malloc(sizeof(*s->right)*(s->nb_samples))))
+ return AVERROR(ENOMEM);
+
+ av_lfg_init(&s->key, av_get_random_seed());
+
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ AtoneContext *s = ctx->priv;
+
+ delete_fluid_synth(s->synth);
+ delete_fluid_settings(s->settings);
+ av_freep(&s->left);
+ av_freep(&s->right);
+}
+
+static av_cold int config_props(AVFilterLink *outlink)
+{
+ AtoneContext *s = outlink->src->priv;
+
+ if (s->duration==0)
+ s->infinite=1;
+ s->duration = av_rescale(s->duration, s->sample_rate, AV_TIME_BASE);
+
+ return 0;
+}
+
+static void gen_random_tone_samples(AtoneContext* s, int buf_size, int key){
+
+ fluid_synth_noteon(s->synth, s->midi_chan, key, s->velocity);
+ fluid_synth_write_float(s->synth, buf_size, s->left, 0, 1, s->right, 0, 1);
+ fluid_synth_noteoff(s->synth, s->midi_chan, key);
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ AtoneContext *s = ctx->priv;
+ AVFrame *frame;
+ int nb_samples, i;
+ unsigned key;
+ float *sample;
+
+ if (!s->infinite && s->duration <= 0) {
+ return AVERROR_EOF;
+ } else if (!s->infinite && s->duration < s->nb_samples) {
+ nb_samples = s->duration;
+ } else {
+ nb_samples = s->nb_samples;
+ }
+
+ if (!(frame = ff_get_audio_buffer(outlink, nb_samples)))
+ return AVERROR(ENOMEM);
+
+
+ if ((s->pts % (s->changerate*nb_samples))== 0){
+ key= av_lfg_get(&s->key);
+ }
+
+ gen_random_tone_samples(s, nb_samples, key%128);
+ sample = (float *)frame->data[0];
+ for (i = 0; i < nb_samples; i++) {
+ sample[2*i]= s->left[i];
+ sample[2*i+1]= s->right[i];
+ }
+
+ if (!s->infinite)
+ s->duration -= nb_samples;
+
+ frame->pts = s->pts;
+ s->pts += nb_samples;
+ return ff_filter_frame(outlink, frame);
+}
+
+static av_cold int query_formats(AVFilterContext *ctx)
+{
+ AtoneContext *s = ctx->priv;
+ static const int64_t chlayouts[] = { AV_CH_LAYOUT_STEREO, -1 };
+ int sample_rates[] = { s->sample_rate, -1 };
+ static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_NONE};
+ AVFilterFormats *formats;
+ AVFilterChannelLayouts *layouts;
+ int ret;
+
+ formats = ff_make_format_list(sample_fmts);
+ if (!formats)
+ return AVERROR(ENOMEM);
+ ret = ff_set_common_formats (ctx, formats);
+ if (ret < 0)
+ return ret;
+
+ layouts = avfilter_make_format64_list(chlayouts);
+ if (!layouts)
+ return AVERROR(ENOMEM);
+ ret = ff_set_common_channel_layouts(ctx, layouts);
+ if (ret < 0)
+ return ret;
+
+ formats = ff_make_format_list(sample_rates);
+ if (!formats)
+ return AVERROR(ENOMEM);
+ return ff_set_common_samplerates(ctx, formats);
+}
+
+
+static const AVFilterPad atone_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .request_frame = request_frame,
+ .config_props = config_props,
+ },
+ { NULL }
+};
+
+AVFilter ff_asrc_atone = {
+ .name = "atone",
+ .description = NULL_IF_CONFIG_SMALL("Generate Random Tones."),
+ .query_formats = query_formats,
+ .init = init,
+ .uninit = uninit,
+ .priv_size = sizeof(AtoneContext),
+ .inputs = NULL,
+ .outputs = atone_outputs,
+ .priv_class = &atone_class,
+};
+
+
+
+
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