ref: 3551f2a82d7c32d6014e477263a8ca242e704a71
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->clips); } 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->clips); } } 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->clips); 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]); free(chan->lastwindow); 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, st_effect_nothing }; const st_effect_t *st_noisered_effect_fn(void) { return &st_noisered_effect; }