Signed-off-by: Paul B Mahol <one...@gmail.com>
---
libavfilter/Makefile | 1 +
libavfilter/af_astretch.c | 330 ++++++++++++++++++++++++++++++++++++++
libavfilter/allfilters.c | 1 +
3 files changed, 332 insertions(+)
create mode 100644 libavfilter/af_astretch.c
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 79a89a1ab1..4a715915fc 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -81,6 +81,7 @@ OBJS-$(CONFIG_ASIDEDATA_FILTER) += f_sidedata.o
OBJS-$(CONFIG_ASPLIT_FILTER) += split.o
OBJS-$(CONFIG_ASTATS_FILTER) += af_astats.o
OBJS-$(CONFIG_ASTREAMSELECT_FILTER) += f_streamselect.o framesync.o
+OBJS-$(CONFIG_ASTRETCH_FILTER) += af_astretch.o
OBJS-$(CONFIG_ATEMPO_FILTER) += af_atempo.o
OBJS-$(CONFIG_ATRIM_FILTER) += trim.o
OBJS-$(CONFIG_AZMQ_FILTER) += f_zmq.o
diff --git a/libavfilter/af_astretch.c b/libavfilter/af_astretch.c
new file mode 100644
index 0000000000..1e39ac3163
--- /dev/null
+++ b/libavfilter/af_astretch.c
@@ -0,0 +1,330 @@
+/*
+ * Copyright (c) 2018 Paul B Mahol
+ *
+ * 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/audio_fifo.h"
+#include "libavutil/avstring.h"
+#include "libavutil/lfg.h"
+#include "libavutil/random_seed.h"
+#include "libavfilter/internal.h"
+#include "libavutil/common.h"
+#include "libavutil/opt.h"
+#include "libavcodec/avfft.h"
+#include "audio.h"
+#include "filters.h"
+#include "window_func.h"
+
+typedef struct AStretchContext {
+ const AVClass *class;
+ double stretch;
+ double overlap;
+ int window_size;
+ int phase;
+ int win_func;
+ int64_t seed;
+
+ int fft_bits;
+ AVAudioFifo *fifo;
+ double start_pos;
+ double displace_pos;
+ int64_t pts;
+ AVFrame *buffer;
+ int start, end;
+ float win_scale;
+ float *window_func_lut;
+
+ AVLFG c;
+ FFTContext *fft;
+ FFTContext *ifft;
+ FFTComplex *fft_data;
+} AStretchContext;
+
+#define OFFSET(x) offsetof(AStretchContext, x)
+#define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption astretch_options[] = {
+ { "stretch", "set stretch factor", OFFSET(stretch),
AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.001, 1000, A },
+ { "overlap", "set overlap factor", OFFSET(overlap),
AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, A },
+ { "winsize", "set window size", OFFSET(window_size), AV_OPT_TYPE_INT,
{.i64=8192}, 16, 65536, A },
+ { "phase", "change phase", OFFSET(phase), AV_OPT_TYPE_BOOL,
{.i64=1}, 0, 1, A },
+ { "winfunc", "set window function", OFFSET(win_func), AV_OPT_TYPE_INT,
{.i64=WFUNC_SINE}, 0, NB_WFUNC-1, A, "winfunc" },
+ { "rect", "Rectangular", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_RECT}, 0, 0, A, "winfunc" },
+ { "bartlett", "Bartlett", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BARTLETT}, 0, 0, A, "winfunc" },
+ { "hann", "Hann", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, A, "winfunc" },
+ { "hanning", "Hanning", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, A, "winfunc" },
+ { "hamming", "Hamming", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_HAMMING}, 0, 0, A, "winfunc" },
+ { "blackman", "Blackman", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BLACKMAN}, 0, 0, A, "winfunc" },
+ { "welch", "Welch", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_WELCH}, 0, 0, A, "winfunc" },
+ { "flattop", "Flat-top", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_FLATTOP}, 0, 0, A, "winfunc" },
+ { "bharris", "Blackman-Harris", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BHARRIS}, 0, 0, A, "winfunc" },
+ { "bnuttall", "Blackman-Nuttall", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BNUTTALL}, 0, 0, A, "winfunc" },
+ { "bhann", "Bartlett-Hann", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BHANN}, 0, 0, A, "winfunc" },
+ { "sine", "Sine", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_SINE}, 0, 0, A, "winfunc" },
+ { "nuttall", "Nuttall", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_NUTTALL}, 0, 0, A, "winfunc" },
+ { "lanczos", "Lanczos", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_LANCZOS}, 0, 0, A, "winfunc" },
+ { "gauss", "Gauss", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_GAUSS}, 0, 0, A, "winfunc" },
+ { "tukey", "Tukey", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_TUKEY}, 0, 0, A, "winfunc" },
+ { "dolph", "Dolph-Chebyshev", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_DOLPH}, 0, 0, A, "winfunc" },
+ { "cauchy", "Cauchy", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_CAUCHY}, 0, 0, A, "winfunc" },
+ { "parzen", "Parzen", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_PARZEN}, 0, 0, A, "winfunc" },
+ { "poisson", "Poisson", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_POISSON}, 0, 0, A, "winfunc" },
+ { "bohman", "Bohman", 0,
AV_OPT_TYPE_CONST, {.i64=WFUNC_BOHMAN}, 0, 0, A, "winfunc" },
+ { "seed", "set random seed", OFFSET(seed),
AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT_MAX, A },
+ { NULL },
+};
+
+AVFILTER_DEFINE_CLASS(astretch);
+
+static int config_input(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AStretchContext *s = ctx->priv;
+ float overlap;
+
+ av_lfg_init(&s->c, s->seed);
+
+ s->fft_bits = av_log2(s->window_size);
+ if (s->phase)
+ s->window_size = 1 << s->fft_bits;
+
+ s->fft = av_fft_init(s->fft_bits, 0);
+ s->ifft = av_fft_init(s->fft_bits, 1);
+ if (!s->ifft || !s->fft)
+ return AVERROR(ENOMEM);
+
+ s->fft_data = av_calloc(s->window_size, sizeof(*s->fft_data));
+ if (!s->fft_data)
+ return AVERROR(ENOMEM);
+
+ s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels,
s->window_size);
+ if (!s->fifo)
+ return AVERROR(ENOMEM);
+
+ s->window_func_lut = av_realloc_f(s->window_func_lut, s->window_size,
+ sizeof(*s->window_func_lut));
+ if (!s->window_func_lut)
+ return AVERROR(ENOMEM);
+ generate_window_func(s->window_func_lut, s->window_size, s->win_func,
&overlap);
+ if (s->overlap == 1)
+ s->overlap = overlap;
+
+ s->buffer = ff_get_audio_buffer(inlink, 2 * s->window_size);
+ if (!s->buffer)
+ return AVERROR(ENOMEM);
+
+ s->start_pos = 0.;
+ s->displace_pos = (s->window_size * (1. - s->overlap)) / s->stretch;
+ s->pts = AV_NOPTS_VALUE;
+
+ return 0;
+}
+
+static int activate(AVFilterContext *ctx)
+{
+ AVFilterLink *inlink = ctx->inputs[0];
+ AVFilterLink *outlink = ctx->outputs[0];
+ AStretchContext *s = ctx->priv;
+ AVFrame *frame = NULL;
+ int ret = 0;
+
+ FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
+
+ if (av_audio_fifo_size(s->fifo) < s->window_size) {
+ ret = ff_inlink_consume_frame(inlink, &frame);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (ret > 0) {
+ if (s->pts == AV_NOPTS_VALUE)
+ s->pts = frame->pts;
+
+ ret = av_audio_fifo_write(s->fifo, (void **)frame->extended_data,
frame->nb_samples);
+ av_frame_free(&frame);
+ if (ret < 0)
+ return ret;
+ }
+
+ if (av_audio_fifo_size(s->fifo) >= s->window_size) {
+ int istart_pos, hwin = s->window_size * (1. - s->overlap);
+ AVFrame *in = ff_get_audio_buffer(outlink, s->window_size);
+ AVFrame *out = ff_get_audio_buffer(outlink, hwin);
+
+ if (!out || !in) {
+ av_frame_free(&in);
+ av_frame_free(&out);
+ return AVERROR(ENOMEM);
+ }
+
+ ret = av_audio_fifo_peek(s->fifo, (void **)in->extended_data,
s->window_size);
+ if (ret < 0) {
+ av_frame_free(&in);
+ av_frame_free(&out);
+ return ret;
+ }
+
+ if (s->phase) {
+ for (int ch = 0; ch < outlink->channels; ch++) {
+ const float *src = (float *)in->extended_data[ch];
+ const float *w = s->window_func_lut;
+ float *ptr = (float *)s->buffer->extended_data[ch];
+ FFTComplex *dst = s->fft_data;
+ float magnitude, phase;
+
+ for (int n = 0; n < s->window_size; n++) {
+ dst[n].re = src[n] * w[n];
+ dst[n].im = 0;
+ }
+
+ av_fft_permute(s->fft, s->fft_data);
+ av_fft_calc(s->fft, s->fft_data);
+
+ for (int n = 0; n < s->window_size; n++) {
+ magnitude = hypotf(dst[n].re, dst[n].im);
+ phase = M_PI * (((2. * av_lfg_get(&s->c)) / (UINT_MAX +
1.0)) - 1.);
+ dst[n].re = magnitude * cos(phase);
+ dst[n].im = magnitude * sin(phase);
+ }
+
+ av_fft_permute(s->ifft, s->fft_data);
+ av_fft_calc(s->ifft, s->fft_data);
+
+ for (int n = 0; n < s->window_size; n++) {
+ const float *w = s->window_func_lut;
+
+ ptr[n] += (dst[n].re / s->window_size) * w[n];
+ }
+ }
+ } else {
+ for (int ch = 0; ch < outlink->channels; ch++) {
+ const float *src = (float *)in->extended_data[ch];
+ float *dst = (float *)s->buffer->extended_data[ch];
+
+ for (int n = 0; n < s->window_size; n++) {
+ dst[n] += src[n];
+ }
+ }
+ }
+
+
+ s->start_pos += s->displace_pos;
+ istart_pos = lrint(floor(s->start_pos));
+ if (istart_pos > 0) {
+ av_audio_fifo_drain(s->fifo, istart_pos);
+ s->start_pos -= istart_pos;
+ }
+ out->pts = s->pts;
+ s->pts += out->nb_samples;
+
+ av_samples_copy(out->extended_data, s->buffer->extended_data,
+ 0, 0, hwin, s->buffer->channels, s->buffer->format);
+
+ for (int ch = 0; ch < outlink->channels; ch++) {
+ float *buf = (float *)s->buffer->extended_data[ch];
+ memmove(buf, buf + hwin, (s->window_size * 2 - hwin) *
sizeof(*buf));
+ }
+
+ for (int ch = 0; ch < outlink->channels; ch++) {
+ float *buf = (float *)s->buffer->extended_data[ch];
+ memset(buf + s->window_size * 2 - hwin, 0, hwin * sizeof(*buf));
+ }
+
+ av_frame_free(&in);
+ return ff_filter_frame(outlink, out);
+ }
+
+ FF_FILTER_FORWARD_STATUS(inlink, outlink);
+ FF_FILTER_FORWARD_WANTED(outlink, inlink);
+
+ return FFERROR_NOT_READY;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ AVFilterFormats *formats;
+ AVFilterChannelLayouts *layouts;
+ static const enum AVSampleFormat sample_fmts[] = {
+ AV_SAMPLE_FMT_FLTP,
+ AV_SAMPLE_FMT_NONE
+ };
+ int ret;
+
+ layouts = ff_all_channel_counts();
+ if (!layouts)
+ return AVERROR(ENOMEM);
+ ret = ff_set_common_channel_layouts(ctx, layouts);
+ if (ret < 0)
+ return 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;
+
+ formats = ff_all_samplerates();
+ if (!formats)
+ return AVERROR(ENOMEM);
+ return ff_set_common_samplerates(ctx, formats);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ AStretchContext *s = ctx->priv;
+
+ av_frame_free(&s->buffer);
+ av_freep(&s->window_func_lut);
+ av_freep(&s->fft_data);
+ av_fft_end(s->fft);
+ s->fft = NULL;
+ av_fft_end(s->ifft);
+ s->ifft = NULL;
+
+ av_audio_fifo_free(s->fifo);
+}
+
+static const AVFilterPad inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .config_props = config_input,
+ },
+ { NULL }
+};
+
+static const AVFilterPad outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ },
+ { NULL }
+};
+
+AVFilter ff_af_astretch = {
+ .name = "astretch",
+ .description = NULL_IF_CONFIG_SMALL("Apply stretch."),
+ .priv_size = sizeof(AStretchContext),
+ .priv_class = &astretch_class,
+ .inputs = inputs,
+ .outputs = outputs,
+ .activate = activate,
+ .query_formats = query_formats,
+ .uninit = uninit,
+};
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 484b080dea..a43376abc7 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -74,6 +74,7 @@ extern AVFilter ff_af_asidedata;
extern AVFilter ff_af_asplit;
extern AVFilter ff_af_astats;
extern AVFilter ff_af_astreamselect;
+extern AVFilter ff_af_astretch;
extern AVFilter ff_af_atempo;
extern AVFilter ff_af_atrim;
extern AVFilter ff_af_azmq;
--
2.17.1
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
