This source file includes following definitions.
- getreal
- getimag
- realf
- imagf
- config_input
- filter_frame
- activate
- query_formats
- uninit
#include "libavutil/audio_fifo.h"
#include "libavutil/avstring.h"
#include "libavfilter/internal.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "libavcodec/avfft.h"
#include "libavutil/eval.h"
#include "audio.h"
#include "filters.h"
#include "window_func.h"
typedef struct AFFTFiltContext {
const AVClass *class;
char *real_str;
char *img_str;
int fft_size;
int fft_bits;
FFTContext *fft, *ifft;
FFTComplex **fft_data;
FFTComplex **fft_temp;
int nb_exprs;
int channels;
int window_size;
AVExpr **real;
AVExpr **imag;
AVAudioFifo *fifo;
int64_t pts;
int hop_size;
float overlap;
AVFrame *buffer;
int eof;
int win_func;
float *window_func_lut;
} AFFTFiltContext;
static const char *const var_names[] = { "sr", "b", "nb", "ch", "chs", "pts", "re", "im", NULL };
enum { VAR_SAMPLE_RATE, VAR_BIN, VAR_NBBINS, VAR_CHANNEL, VAR_CHANNELS, VAR_PTS, VAR_REAL, VAR_IMAG, VAR_VARS_NB };
#define OFFSET(x) offsetof(AFFTFiltContext, x)
#define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption afftfilt_options[] = {
{ "real", "set channels real expressions", OFFSET(real_str), AV_OPT_TYPE_STRING, {.str = "re" }, 0, 0, A },
{ "imag", "set channels imaginary expressions", OFFSET(img_str), AV_OPT_TYPE_STRING, {.str = "im" }, 0, 0, A },
{ "win_size", "set window size", OFFSET(fft_size), AV_OPT_TYPE_INT, {.i64=4096}, 16, 131072, A },
{ "win_func", "set window function", OFFSET(win_func), AV_OPT_TYPE_INT, {.i64 = WFUNC_HANNING}, 0, NB_WFUNC-1, A, "win_func" },
{ "rect", "Rectangular", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_RECT}, 0, 0, A, "win_func" },
{ "bartlett", "Bartlett", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BARTLETT}, 0, 0, A, "win_func" },
{ "hann", "Hann", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, A, "win_func" },
{ "hanning", "Hanning", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HANNING}, 0, 0, A, "win_func" },
{ "hamming", "Hamming", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_HAMMING}, 0, 0, A, "win_func" },
{ "blackman", "Blackman", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BLACKMAN}, 0, 0, A, "win_func" },
{ "welch", "Welch", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_WELCH}, 0, 0, A, "win_func" },
{ "flattop", "Flat-top", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_FLATTOP}, 0, 0, A, "win_func" },
{ "bharris", "Blackman-Harris", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BHARRIS}, 0, 0, A, "win_func" },
{ "bnuttall", "Blackman-Nuttall", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BNUTTALL}, 0, 0, A, "win_func" },
{ "bhann", "Bartlett-Hann", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BHANN}, 0, 0, A, "win_func" },
{ "sine", "Sine", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_SINE}, 0, 0, A, "win_func" },
{ "nuttall", "Nuttall", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_NUTTALL}, 0, 0, A, "win_func" },
{ "lanczos", "Lanczos", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_LANCZOS}, 0, 0, A, "win_func" },
{ "gauss", "Gauss", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_GAUSS}, 0, 0, A, "win_func" },
{ "tukey", "Tukey", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_TUKEY}, 0, 0, A, "win_func" },
{ "dolph", "Dolph-Chebyshev", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_DOLPH}, 0, 0, A, "win_func" },
{ "cauchy", "Cauchy", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_CAUCHY}, 0, 0, A, "win_func" },
{ "parzen", "Parzen", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_PARZEN}, 0, 0, A, "win_func" },
{ "poisson", "Poisson", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_POISSON}, 0, 0, A, "win_func" },
{ "bohman", "Bohman", 0, AV_OPT_TYPE_CONST, {.i64=WFUNC_BOHMAN}, 0, 0, A, "win_func" },
{ "overlap", "set window overlap", OFFSET(overlap), AV_OPT_TYPE_FLOAT, {.dbl=0.75}, 0, 1, A },
{ NULL },
};
AVFILTER_DEFINE_CLASS(afftfilt);
static inline double getreal(void *priv, double x, double ch)
{
AFFTFiltContext *s = priv;
int ich, ix;
ich = av_clip(ch, 0, s->nb_exprs - 1);
ix = av_clip(x, 0, s->window_size / 2);
return s->fft_data[ich][ix].re;
}
static inline double getimag(void *priv, double x, double ch)
{
AFFTFiltContext *s = priv;
int ich, ix;
ich = av_clip(ch, 0, s->nb_exprs - 1);
ix = av_clip(x, 0, s->window_size / 2);
return s->fft_data[ich][ix].im;
}
static double realf(void *priv, double x, double ch) { return getreal(priv, x, ch); }
static double imagf(void *priv, double x, double ch) { return getimag(priv, x, ch); }
static const char *const func2_names[] = { "real", "imag", NULL };
double (*func2[])(void *, double, double) = { realf, imagf, NULL };
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
AFFTFiltContext *s = ctx->priv;
char *saveptr = NULL;
int ret = 0, ch;
float overlap;
char *args;
const char *last_expr = "1";
s->channels = inlink->channels;
s->pts = AV_NOPTS_VALUE;
s->fft_bits = av_log2(s->fft_size);
s->fft = av_fft_init(s->fft_bits, 0);
s->ifft = av_fft_init(s->fft_bits, 1);
if (!s->fft || !s->ifft)
return AVERROR(ENOMEM);
s->window_size = 1 << s->fft_bits;
s->fft_data = av_calloc(inlink->channels, sizeof(*s->fft_data));
if (!s->fft_data)
return AVERROR(ENOMEM);
s->fft_temp = av_calloc(inlink->channels, sizeof(*s->fft_temp));
if (!s->fft_temp)
return AVERROR(ENOMEM);
for (ch = 0; ch < inlink->channels; ch++) {
s->fft_data[ch] = av_calloc(s->window_size, sizeof(**s->fft_data));
if (!s->fft_data[ch])
return AVERROR(ENOMEM);
}
for (ch = 0; ch < inlink->channels; ch++) {
s->fft_temp[ch] = av_calloc(s->window_size, sizeof(**s->fft_temp));
if (!s->fft_temp[ch])
return AVERROR(ENOMEM);
}
s->real = av_calloc(inlink->channels, sizeof(*s->real));
if (!s->real)
return AVERROR(ENOMEM);
s->imag = av_calloc(inlink->channels, sizeof(*s->imag));
if (!s->imag)
return AVERROR(ENOMEM);
args = av_strdup(s->real_str);
if (!args)
return AVERROR(ENOMEM);
for (ch = 0; ch < inlink->channels; ch++) {
char *arg = av_strtok(ch == 0 ? args : NULL, "|", &saveptr);
ret = av_expr_parse(&s->real[ch], arg ? arg : last_expr, var_names,
NULL, NULL, func2_names, func2, 0, ctx);
if (ret < 0)
goto fail;
if (arg)
last_expr = arg;
s->nb_exprs++;
}
av_freep(&args);
args = av_strdup(s->img_str ? s->img_str : s->real_str);
if (!args)
return AVERROR(ENOMEM);
saveptr = NULL;
last_expr = "1";
for (ch = 0; ch < inlink->channels; ch++) {
char *arg = av_strtok(ch == 0 ? args : NULL, "|", &saveptr);
ret = av_expr_parse(&s->imag[ch], arg ? arg : last_expr, var_names,
NULL, NULL, func2_names, func2, 0, ctx);
if (ret < 0)
goto fail;
if (arg)
last_expr = arg;
}
av_freep(&args);
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->hop_size = s->window_size * (1 - s->overlap);
if (s->hop_size <= 0)
return AVERROR(EINVAL);
s->buffer = ff_get_audio_buffer(inlink, s->window_size * 2);
if (!s->buffer)
return AVERROR(ENOMEM);
fail:
av_freep(&args);
return ret;
}
static int filter_frame(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
AFFTFiltContext *s = ctx->priv;
const int window_size = s->window_size;
const float f = 1. / (s->window_size / 2);
double values[VAR_VARS_NB];
AVFrame *out, *in = NULL;
int ch, n, ret, i;
if (!in) {
in = ff_get_audio_buffer(outlink, window_size);
if (!in)
return AVERROR(ENOMEM);
}
ret = av_audio_fifo_peek(s->fifo, (void **)in->extended_data, window_size);
if (ret < 0)
goto fail;
for (ch = 0; ch < inlink->channels; ch++) {
const float *src = (float *)in->extended_data[ch];
FFTComplex *fft_data = s->fft_data[ch];
for (n = 0; n < in->nb_samples; n++) {
fft_data[n].re = src[n] * s->window_func_lut[n];
fft_data[n].im = 0;
}
for (; n < window_size; n++) {
fft_data[n].re = 0;
fft_data[n].im = 0;
}
}
values[VAR_PTS] = s->pts;
values[VAR_SAMPLE_RATE] = inlink->sample_rate;
values[VAR_NBBINS] = window_size / 2;
values[VAR_CHANNELS] = inlink->channels;
for (ch = 0; ch < inlink->channels; ch++) {
FFTComplex *fft_data = s->fft_data[ch];
av_fft_permute(s->fft, fft_data);
av_fft_calc(s->fft, fft_data);
}
for (ch = 0; ch < inlink->channels; ch++) {
FFTComplex *fft_data = s->fft_data[ch];
FFTComplex *fft_temp = s->fft_temp[ch];
float *buf = (float *)s->buffer->extended_data[ch];
int x;
values[VAR_CHANNEL] = ch;
for (n = 0; n <= window_size / 2; n++) {
float fr, fi;
values[VAR_BIN] = n;
values[VAR_REAL] = fft_data[n].re;
values[VAR_IMAG] = fft_data[n].im;
fr = av_expr_eval(s->real[ch], values, s);
fi = av_expr_eval(s->imag[ch], values, s);
fft_temp[n].re = fr;
fft_temp[n].im = fi;
}
for (n = window_size / 2 + 1, x = window_size / 2 - 1; n < window_size; n++, x--) {
fft_temp[n].re = fft_temp[x].re;
fft_temp[n].im = -fft_temp[x].im;
}
av_fft_permute(s->ifft, fft_temp);
av_fft_calc(s->ifft, fft_temp);
for (i = 0; i < window_size; i++) {
buf[i] += s->fft_temp[ch][i].re * f;
}
}
out = ff_get_audio_buffer(outlink, s->hop_size);
if (!out) {
ret = AVERROR(ENOMEM);
goto fail;
}
out->pts = s->pts;
s->pts += av_rescale_q(s->hop_size, (AVRational){1, outlink->sample_rate}, outlink->time_base);
for (ch = 0; ch < inlink->channels; ch++) {
float *dst = (float *)out->extended_data[ch];
float *buf = (float *)s->buffer->extended_data[ch];
for (n = 0; n < s->hop_size; n++)
dst[n] = buf[n] * (1.f - s->overlap);
memmove(buf, buf + s->hop_size, window_size * 4);
}
ret = ff_filter_frame(outlink, out);
if (ret < 0)
goto fail;
av_audio_fifo_drain(s->fifo, s->hop_size);
fail:
av_frame_free(&in);
return ret < 0 ? ret : 0;
}
static int activate(AVFilterContext *ctx)
{
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
AFFTFiltContext *s = ctx->priv;
AVFrame *in = NULL;
int ret = 0, status;
int64_t pts;
FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink);
if (!s->eof && av_audio_fifo_size(s->fifo) < s->window_size) {
ret = ff_inlink_consume_frame(inlink, &in);
if (ret < 0)
return ret;
if (ret > 0) {
ret = av_audio_fifo_write(s->fifo, (void **)in->extended_data,
in->nb_samples);
if (ret >= 0 && s->pts == AV_NOPTS_VALUE)
s->pts = in->pts;
av_frame_free(&in);
if (ret < 0)
return ret;
}
}
if ((av_audio_fifo_size(s->fifo) >= s->window_size) ||
(av_audio_fifo_size(s->fifo) > 0 && s->eof)) {
ret = filter_frame(inlink);
if (av_audio_fifo_size(s->fifo) >= s->window_size)
ff_filter_set_ready(ctx, 100);
return ret;
}
if (!s->eof && ff_inlink_acknowledge_status(inlink, &status, &pts)) {
if (status == AVERROR_EOF) {
s->eof = 1;
if (av_audio_fifo_size(s->fifo) >= 0) {
ff_filter_set_ready(ctx, 100);
return 0;
}
}
}
if (s->eof && av_audio_fifo_size(s->fifo) <= 0) {
ff_outlink_set_status(outlink, AVERROR_EOF, s->pts);
return 0;
}
if (!s->eof)
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)
{
AFFTFiltContext *s = ctx->priv;
int i;
av_fft_end(s->fft);
av_fft_end(s->ifft);
for (i = 0; i < s->channels; i++) {
if (s->fft_data)
av_freep(&s->fft_data[i]);
if (s->fft_temp)
av_freep(&s->fft_temp[i]);
}
av_freep(&s->fft_data);
av_freep(&s->fft_temp);
for (i = 0; i < s->nb_exprs; i++) {
av_expr_free(s->real[i]);
av_expr_free(s->imag[i]);
}
av_freep(&s->real);
av_freep(&s->imag);
av_frame_free(&s->buffer);
av_freep(&s->window_func_lut);
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_afftfilt = {
.name = "afftfilt",
.description = NULL_IF_CONFIG_SMALL("Apply arbitrary expressions to samples in frequency domain."),
.priv_size = sizeof(AFFTFiltContext),
.priv_class = &afftfilt_class,
.inputs = inputs,
.outputs = outputs,
.activate = activate,
.query_formats = query_formats,
.uninit = uninit,
};