/*
* Copyright (c) 2019 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 <float.h>
#include <math.h>
#include "libavcodec/avfft.h"
#include "libavutil/audio_fifo.h"
#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "audio.h"
#include "video.h"
#include "avfilter.h"
#include "filters.h"
#include "internal.h"
#include "window_func.h"
typedef struct ShowSpatialContext {
const AVClass *class;
int w, h;
AVRational frame_rate;
FFTContext *fft[2]; ///< Fast Fourier Transform context
FFTContext *ifft[2]; ///< Inverse Fast Fourier Transform context
int fft_bits; ///< number of bits (FFT window size = 1<<fft_bits)
FFTComplex *fft_data[2]; ///< bins holder for each (displayed) channels
float *window_func_lut; ///< Window function LUT
int win_func;
int win_size;
int buf_size;
float overlap;
int consumed;
int hop_size;
AVAudioFifo *fifo;
int64_t pts;
} ShowSpatialContext;
#define OFFSET(x) offsetof(ShowSpatialContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption showspatial_options[] = {
{ "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "512x512"}, 0, 0, FLAGS },
{ "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "512x512"}, 0, 0, FLAGS },
{ "win_size", "set window size", OFFSET(win_size), AV_OPT_TYPE_INT, {.i64 = 4096}, 1024, 65536, FLAGS },
{ "win_func", "set window function", OFFSET(win_func), AV_OPT_TYPE_INT, {.i64 = WFUNC_HANNING}, 0, NB_WFUNC-1, FLAGS, "win_func" },
{ "rect", "Rectangular", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_RECT}, 0, 0, FLAGS, "win_func" },
{ "bartlett", "Bartlett", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BARTLETT}, 0, 0, FLAGS, "win_func" },
{ "hann", "Hann", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, FLAGS, "win_func" },
{ "hanning", "Hanning", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, FLAGS, "win_func" },
{ "hamming", "Hamming", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HAMMING}, 0, 0, FLAGS, "win_func" },
{ "blackman", "Blackman", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BLACKMAN}, 0, 0, FLAGS, "win_func" },
{ "welch", "Welch", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_WELCH}, 0, 0, FLAGS, "win_func" },
{ "flattop", "Flat-top", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_FLATTOP}, 0, 0, FLAGS, "win_func" },
{ "bharris", "Blackman-Harris", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BHARRIS}, 0, 0, FLAGS, "win_func" },
{ "bnuttall", "Blackman-Nuttall", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BNUTTALL}, 0, 0, FLAGS, "win_func" },
{ "bhann", "Bartlett-Hann", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BHANN}, 0, 0, FLAGS, "win_func" },
{ "sine", "Sine", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_SINE}, 0, 0, FLAGS, "win_func" },
{ "nuttall", "Nuttall", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_NUTTALL}, 0, 0, FLAGS, "win_func" },
{ "lanczos", "Lanczos", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_LANCZOS}, 0, 0, FLAGS, "win_func" },
{ "gauss", "Gauss", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_GAUSS}, 0, 0, FLAGS, "win_func" },
{ "tukey", "Tukey", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_TUKEY}, 0, 0, FLAGS, "win_func" },
{ "dolph", "Dolph-Chebyshev", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_DOLPH}, 0, 0, FLAGS, "win_func" },
{ "cauchy", "Cauchy", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_CAUCHY}, 0, 0, FLAGS, "win_func" },
{ "parzen", "Parzen", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_PARZEN}, 0, 0, FLAGS, "win_func" },
{ "poisson", "Poisson", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_POISSON}, 0, 0, FLAGS, "win_func" },
{ "bohman", "Bohman", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BOHMAN}, 0, 0, FLAGS, "win_func" },
{ "overlap", "set window overlap", OFFSET(overlap), AV_OPT_TYPE_FLOAT, {.dbl=0.5}, 0, 1, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(showspatial);
static av_cold void uninit(AVFilterContext *ctx)
{
ShowSpatialContext *s = ctx->priv;
int i;
for (i = 0; i < 2; i++)
av_fft_end(s->fft[i]);
for (i = 0; i < 2; i++)
av_fft_end(s->ifft[i]);
for (i = 0; i < 2; i++)
av_freep(&s->fft_data[i]);
av_freep(&s->window_func_lut);
av_audio_fifo_free(s->fifo);
}
static int query_formats(AVFilterContext *ctx)
{
AVFilterFormats *formats = NULL;
AVFilterChannelLayouts *layout = NULL;
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE };
static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GBRP, AV_PIX_FMT_NONE };
int ret;
formats = ff_make_format_list(sample_fmts);
if ((ret = ff_formats_ref (formats, &inlink->out_formats )) < 0 ||
(ret = ff_add_channel_layout (&layout, AV_CH_LAYOUT_STEREO )) < 0 ||
(ret = ff_channel_layouts_ref (layout , &inlink->out_channel_layouts)) < 0)
return ret;
formats = ff_all_samplerates();
if ((ret = ff_formats_ref(formats, &inlink->out_samplerates)) < 0)
return ret;
formats = ff_make_format_list(pix_fmts);
if ((ret = ff_formats_ref(formats, &outlink->in_formats)) < 0)
return ret;
return 0;
}
static int run_channel_fft(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
{
ShowSpatialContext *s = ctx->priv;
const float *window_func_lut = s->window_func_lut;
AVFrame *fin = arg;
const int ch = jobnr;
const float *p = (float *)fin->extended_data[ch];
for (int n = 0; n < fin->nb_samples; n++) {
s->fft_data[ch][n].re = p[n] * window_func_lut[n];
s->fft_data[ch][n].im = 0;
}
av_fft_permute(s->fft[ch], s->fft_data[ch]);
av_fft_calc(s->fft[ch], s->fft_data[ch]);
return 0;
}
static int config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
AVFilterLink *inlink = ctx->inputs[0];
ShowSpatialContext *s = ctx->priv;
int i, fft_bits;
float overlap;
outlink->w = s->w;
outlink->h = s->h;
outlink->sample_aspect_ratio = (AVRational){1,1};
s->buf_size = 1 << av_log2(s->win_size);
s->win_size = s->buf_size;
fft_bits = av_log2(s->win_size);
/* (re-)configuration if the video output changed (or first init) */
if (fft_bits != s->fft_bits) {
s->fft_bits = fft_bits;
/* FFT buffers: x2 for each channel buffer.
* Note: we use free and malloc instead of a realloc-like function to
* make sure the buffer is aligned in memory for the FFT functions. */
for (i = 0; i < 2; i++) {
av_fft_end(s->fft[i]);
av_freep(&s->fft_data[i]);
}
for (i = 0; i < 2; i++) {
s->fft[i] = av_fft_init(fft_bits, 0);
if (!s->fft[i]) {
av_log(ctx, AV_LOG_ERROR, "Unable to create FFT context. "
"The window size might be too high.\n");
return AVERROR(EINVAL);
}
}
for (i = 0; i < 2; i++) {
s->fft_data[i] = av_calloc(s->buf_size, sizeof(**s->fft_data));
if (!s->fft_data[i])
return AVERROR(ENOMEM);
}
/* pre-calc windowing function */
s->window_func_lut =
av_realloc_f(s->window_func_lut, s->win_size,
sizeof(*s->window_func_lut));
if (!s->window_func_lut)
return AVERROR(ENOMEM);
generate_window_func(s->window_func_lut, s->win_size, s->win_func, &overlap);
if (s->overlap == 1)
s->overlap = overlap;
s->hop_size = (1.f - s->overlap) * s->win_size;
if (s->hop_size < 1) {
av_log(ctx, AV_LOG_ERROR, "overlap %f too big\n", s->overlap);
return AVERROR(EINVAL);
}
}
outlink->time_base = av_inv_q(outlink->frame_rate);
av_audio_fifo_free(s->fifo);
s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels, s->win_size);
if (!s->fifo)
return AVERROR(ENOMEM);
return 0;
}
#define RE(y, ch) s->fft_data[ch][y].re
#define IM(y, ch) s->fft_data[ch][y].im
static void draw_dot(uint8_t *dst, int linesize, int value)
{
dst[0] = value;
dst[1] = value;
dst[-1] = value;
dst[linesize] = value;
dst[-linesize] = value;
}
static int draw_spatial(AVFilterLink *inlink, AVFrame *insamples)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
ShowSpatialContext *s = ctx->priv;
AVFrame *outpicref;
int h = s->h - 2;
int w = s->w - 2;
int z = s->win_size / 2;
outpicref = ff_get_video_buffer(outlink, outlink->w, outlink->h);
if (!outpicref)
return AVERROR(ENOMEM);
outpicref->sample_aspect_ratio = (AVRational){1,1};
for (int i = 0; i < outlink->h; i++) {
memset(outpicref->data[0] + i * outpicref->linesize[0], 0, outlink->w);
memset(outpicref->data[1] + i * outpicref->linesize[1], 0, outlink->w);
memset(outpicref->data[2] + i * outpicref->linesize[2], 0, outlink->w);
}
for (int j = 0; j < z; j++) {
const int idx = z - 1 - j;
float l = hypotf(RE(idx, 0), IM(idx, 0));
float r = hypotf(RE(idx, 1), IM(idx, 1));
float sum = l + r;
float lp = atan2f(IM(idx, 0), RE(idx, 0));
float rp = atan2f(IM(idx, 1), RE(idx, 1));
float diffp = ((rp - lp) / (2.f * M_PI) + 1.f) * 0.5f;
float diff = (sum < 0.000001f ? 0.f : (r - l) / sum) * 0.5f + 0.5f;
float cr = av_clipf(cbrtf(l / sum), 0, 1) * 255.f;
float cb = av_clipf(cbrtf(r / sum), 0, 1) * 255.f;
float cg;
int x, y;
cg = diffp * 255.f;
x = av_clip(w * diff, 0, w - 2) + 1;
y = av_clip(h * diffp, 0, h - 2) + 1;
draw_dot(outpicref->data[0] + outpicref->linesize[0] * y + x, outpicref->linesize[0], cg);
draw_dot(outpicref->data[1] + outpicref->linesize[1] * y + x, outpicref->linesize[1], cb);
draw_dot(outpicref->data[2] + outpicref->linesize[2] * y + x, outpicref->linesize[2], cr);
}
outpicref->pts = av_rescale_q(insamples->pts, inlink->time_base, outlink->time_base);
return ff_filter_frame(outlink, outpicref);
}
static int spatial_activate(AVFilterContext *ctx)
{
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
ShowSpatialContext *s = ctx->priv;
int ret;
FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
if (av_audio_fifo_size(s->fifo) < s->win_size) {
AVFrame *frame = NULL;
ret = ff_inlink_consume_frame(inlink, &frame);
if (ret < 0)
return ret;
if (ret > 0) {
s->pts = frame->pts;
s->consumed = 0;
av_audio_fifo_write(s->fifo, (void **)frame->extended_data, frame->nb_samples);
av_frame_free(&frame);
}
}
if (av_audio_fifo_size(s->fifo) >= s->win_size) {
AVFrame *fin = ff_get_audio_buffer(inlink, s->win_size);
if (!fin)
return AVERROR(ENOMEM);
fin->pts = s->pts + s->consumed;
s->consumed += s->hop_size;
ret = av_audio_fifo_peek(s->fifo, (void **)fin->extended_data,
FFMIN(s->win_size, av_audio_fifo_size(s->fifo)));
if (ret < 0) {
av_frame_free(&fin);
return ret;
}
av_assert0(fin->nb_samples == s->win_size);
ctx->internal->execute(ctx, run_channel_fft, fin, NULL, 2);
ret = draw_spatial(inlink, fin);
av_frame_free(&fin);
av_audio_fifo_drain(s->fifo, s->hop_size);
if (ret <= 0)
return ret;
}
FF_FILTER_FORWARD_STATUS(inlink, outlink);
if (ff_outlink_frame_wanted(outlink) && av_audio_fifo_size(s->fifo) < s->win_size) {
ff_inlink_request_frame(inlink);
return 0;
}
if (av_audio_fifo_size(s->fifo) >= s->win_size) {
ff_filter_set_ready(ctx, 10);
return 0;
}
return FFERROR_NOT_READY;
}
static const AVFilterPad showspatial_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
},
{ NULL }
};
static const AVFilterPad showspatial_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
AVFilter ff_avf_showspatial = {
.name = "showspatial",
.description = NULL_IF_CONFIG_SMALL("Convert input audio to a spatial video output."),
.uninit = uninit,
.query_formats = query_formats,
.priv_size = sizeof(ShowSpatialContext),
.inputs = showspatial_inputs,
.outputs = showspatial_outputs,
.activate = spatial_activate,
.priv_class = &showspatial_class,
.flags = AVFILTER_FLAG_SLICE_THREADS,
};