ref: 709570b2f9deb1fb83e50403d22e093dede4f780
dir: /src/noisered.c/
/*
* noiseprof - Noise Profiling Effect.
*
* Written by Ian Turner (vectro@vectro.org)
*
* Copyright 1999 Ian Turner
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Authors are not responsible for the consequences of using this software.
*/
#include "noisered.h"
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <assert.h>
static st_effect_t st_noisered_effect;
typedef struct chandata {
float *window;
float *lastwindow;
float *noisegate;
float *smoothing;
} chandata_t;
/* Holds profile information */
typedef struct reddata {
char* profile_filename;
float threshold;
chandata_t *chandata;
st_size_t bufdata;
} * reddata_t;
/*
* Get the options. Filename is mandatory, though a reasonable default would
* be stdin (if the input file isn't coming from there, of course!)
*/
static int st_noisered_getopts(eff_t effp, int n, char **argv)
{
reddata_t data = (reddata_t) effp->priv;
if (n > 2 || n < 1) {
st_fail(st_noisered_effect.usage);
return (ST_EOF);
}
data->threshold = 0.5;
data->profile_filename = argv[0];
if (n == 2)
{
data->threshold = atof(argv[1]);
if (data->threshold > 1)
{
data->threshold = 1;
} else if (data->threshold < 0)
{
data->threshold = 0;
}
}
return (ST_SUCCESS);
}
/*
* Prepare processing.
* Do all initializations.
*/
static int st_noisered_start(eff_t effp)
{
reddata_t data = (reddata_t) effp->priv;
int fchannels = 0;
int channels = effp->ininfo.channels;
int i;
FILE* ifd;
data->chandata = (chandata_t*)xcalloc(channels, sizeof(*(data->chandata)));
data->bufdata = 0;
for (i = 0; i < channels; i ++) {
data->chandata[i].noisegate = (float*)xcalloc(FREQCOUNT, sizeof(float));
data->chandata[i].smoothing = (float*)xcalloc(FREQCOUNT, sizeof(float));
data->chandata[i].lastwindow = NULL;
}
/* Here we actually open the input file. */
ifd = fopen(data->profile_filename, "r");
if (ifd == NULL) {
st_fail("Couldn't open profile file %s: %s",
data->profile_filename, strerror(errno));
return ST_EOF;
}
while (1) {
int i1;
float f1;
if (2 != fscanf(ifd, " Channel %d: %f", &i1, &f1))
break;
if (i1 != fchannels) {
st_fail("noisered: Got channel %d, expected channel %d.",
i1, fchannels);
return ST_EOF;
}
data->chandata[fchannels].noisegate[0] = f1;
for (i = 1; i < FREQCOUNT; i ++) {
if (1 != fscanf(ifd, ", %f", &f1)) {
st_fail("noisered: Not enough datums for channel %d "
"(expected %d, got %d)", fchannels, FREQCOUNT, i);
return ST_EOF;
}
data->chandata[fchannels].noisegate[i] = f1;
}
fchannels ++;
}
if (fchannels != channels) {
st_fail("noisered: channel mismatch: %d in input, %d in profile.",
channels, fchannels);
return ST_EOF;
}
fclose(ifd);
return (ST_SUCCESS);
}
/* Mangle a single window. Each output sample (except the first and last
* half-window) is the result of two distinct calls to this function,
* due to overlapping windows. */
static void reduce_noise(chandata_t* chan, float* window, float level)
{
float *inr, *ini, *outr, *outi, *power;
float *smoothing = chan->smoothing;
int i;
inr = (float*)xcalloc(WINDOWSIZE * 5, sizeof(float));
ini = inr + WINDOWSIZE;
outr = ini + WINDOWSIZE;
outi = outr + WINDOWSIZE;
power = outi + WINDOWSIZE;
for (i = 0; i < FREQCOUNT; i ++)
assert(smoothing[i] >= 0 && smoothing[i] <= 1);
memcpy(inr, window, WINDOWSIZE*sizeof(float));
FFT(WINDOWSIZE, 0, inr, NULL, outr, outi);
memcpy(inr, window, WINDOWSIZE*sizeof(float));
WindowFunc(HANNING, WINDOWSIZE, inr);
PowerSpectrum(WINDOWSIZE, inr, power);
for (i = 0; i < FREQCOUNT; i ++) {
float smooth;
float plog;
plog = log(power[i]);
if (power[i] != 0 && plog < chan->noisegate[i] + level*8.0)
smooth = 0.0;
else
smooth = 1.0;
smoothing[i] = smooth * 0.5 + smoothing[i] * 0.5;
}
/* Audacity says this code will eliminate tinkle bells.
* I have no idea what that means. */
for (i = 2; i < FREQCOUNT - 2; i ++) {
if (smoothing[i]>=0.5 &&
smoothing[i]<=0.55 &&
smoothing[i-1]<0.1 &&
smoothing[i-2]<0.1 &&
smoothing[i+1]<0.1 &&
smoothing[i+2]<0.1)
smoothing[i] = 0.0;
}
outr[0] *= smoothing[0];
outi[0] *= smoothing[0];
outr[FREQCOUNT-1] *= smoothing[FREQCOUNT-1];
outi[FREQCOUNT-1] *= smoothing[FREQCOUNT-1];
for (i = 1; i < FREQCOUNT-1; i ++) {
int j = WINDOWSIZE - i;
float smooth = smoothing[i];
outr[i] *= smooth;
outi[i] *= smooth;
outr[j] *= smooth;
outi[j] *= smooth;
}
FFT(WINDOWSIZE, 1, outr, outi, inr, ini);
WindowFunc(HANNING, WINDOWSIZE, inr);
memcpy(window, inr, WINDOWSIZE*sizeof(float));
for (i = 0; i < FREQCOUNT; i ++)
assert(smoothing[i] >= 0 && smoothing[i] <= 1);
free(inr);
}
/* Do window management once we have a complete window, including mangling
* the current window. */
static int process_window(eff_t effp, reddata_t data, int chan_num, int num_chans,
st_sample_t *obuf, int len) {
int j;
float* nextwindow;
int use = min(len, WINDOWSIZE)-min(len,(WINDOWSIZE/2));
chandata_t *chan = &(data->chandata[chan_num]);
int first = (chan->lastwindow == NULL);
if ((nextwindow = (float*)xcalloc(WINDOWSIZE, sizeof(float))) == NULL)
return ST_EOF;
memcpy(nextwindow, chan->window+WINDOWSIZE/2,
sizeof(float)*(WINDOWSIZE/2));
reduce_noise(chan, chan->window, data->threshold);
if (!first) {
for (j = 0; j < use; j ++) {
float s = chan->window[j] + chan->lastwindow[WINDOWSIZE/2 + j];
obuf[chan_num + num_chans * j] =
ST_FLOAT_DWORD_TO_SAMPLE(s, effp->clippedCount);
}
free(chan->lastwindow);
} else {
for (j = 0; j < use; j ++) {
assert(chan->window[j] >= -1 && chan->window[j] <= 1);
obuf[chan_num + num_chans * j] =
ST_FLOAT_DWORD_TO_SAMPLE(chan->window[j], effp->clippedCount);
}
}
chan->lastwindow = chan->window;
chan->window = nextwindow;
return use;
}
/*
* Read in windows, and call process_window once we get a whole one.
*/
static int st_noisered_flow(eff_t effp, const st_sample_t *ibuf, st_sample_t *obuf,
st_size_t *isamp, st_size_t *osamp)
{
reddata_t data = (reddata_t) effp->priv;
st_size_t samp = min(*isamp, *osamp);
st_size_t tracks = effp->ininfo.channels;
st_size_t track_samples = samp / tracks;
st_size_t ncopy = min(track_samples, WINDOWSIZE-data->bufdata);
st_size_t whole_window = (ncopy + data->bufdata == WINDOWSIZE);
int oldbuf = data->bufdata;
st_size_t i;
assert(effp->ininfo.channels == effp->outinfo.channels);
if (whole_window)
data->bufdata = WINDOWSIZE/2;
else
data->bufdata += ncopy;
/* Reduce noise on every channel. */
for (i = 0; i < tracks; i ++) {
chandata_t* chan = &(data->chandata[i]);
st_size_t j;
if (chan->window == NULL)
chan->window = (float*)xcalloc(WINDOWSIZE, sizeof(float));
for (j = 0; j < ncopy; j ++)
chan->window[oldbuf + j] =
ST_SAMPLE_TO_FLOAT_DWORD(ibuf[i + tracks * j], effp->clippedCount);
if (!whole_window)
continue;
else
process_window(effp, data, i, tracks, obuf, oldbuf + ncopy);
}
*isamp = tracks*ncopy;
if (whole_window)
*osamp = tracks*(WINDOWSIZE/2);
else
*osamp = 0;
return ST_SUCCESS;
}
/*
* We have up to half a window left to dump.
*/
static int st_noisered_drain(eff_t effp, st_sample_t *obuf, st_size_t *osamp)
{
reddata_t data = (reddata_t)effp->priv;
int i;
int tracks = effp->ininfo.channels;
for (i = 0; i < tracks; i ++)
*osamp = process_window(effp, data, i, tracks, obuf, data->bufdata);
/* FIXME: This is very picky. osamp needs to be big enough to get all
* remaining data or it will be discarded.
*/
return (ST_EOF);
}
/*
* Clean up.
*/
static int st_noisered_stop(eff_t effp)
{
reddata_t data = (reddata_t) effp->priv;
st_size_t i;
for (i = 0; i < effp->ininfo.channels; i ++) {
chandata_t* chan = &(data->chandata[i]);
if (chan->lastwindow != NULL) {
free(chan->lastwindow);
}
if (chan->window != NULL) {
free(chan->window);
}
free(chan->smoothing);
free(chan->noisegate);
}
free(data->chandata);
return (ST_SUCCESS);
}
static st_effect_t st_noisered_effect = {
"noisered",
"Usage: noiseprof profile-file [threshold]",
ST_EFF_MCHAN,
st_noisered_getopts,
st_noisered_start,
st_noisered_flow,
st_noisered_drain,
st_noisered_stop
};
const st_effect_t *st_noisered_effect_fn(void)
{
return &st_noisered_effect;
}
/* For Emacs:
Local Variables:
c-basic-offset: 4
*/