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author | Matthias P. Braendli <matthias.braendli@mpb.li> | 2016-02-15 02:44:20 +0100 |
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committer | Matthias P. Braendli <matthias.braendli@mpb.li> | 2016-02-15 02:44:20 +0100 |
commit | 22f1fce330059ef8a383cf327a023d6a9da5ad3e (patch) | |
tree | 6893f158dcaaaa1b9f1317923c32a841ba31f768 /libtoolame-dab/psycho_1.c | |
parent | 891bb2592944aa2be2d81e1583e73e632e70537f (diff) | |
download | fdk-aac-22f1fce330059ef8a383cf327a023d6a9da5ad3e.tar.gz fdk-aac-22f1fce330059ef8a383cf327a023d6a9da5ad3e.tar.bz2 fdk-aac-22f1fce330059ef8a383cf327a023d6a9da5ad3e.zip |
Include toolame-dab as library
Diffstat (limited to 'libtoolame-dab/psycho_1.c')
-rw-r--r-- | libtoolame-dab/psycho_1.c | 601 |
1 files changed, 601 insertions, 0 deletions
diff --git a/libtoolame-dab/psycho_1.c b/libtoolame-dab/psycho_1.c new file mode 100644 index 0000000..004813c --- /dev/null +++ b/libtoolame-dab/psycho_1.c @@ -0,0 +1,601 @@ +#include <stdio.h> +#include <math.h> +#include "common.h" +#include "encoder.h" +#include "mem.h" +#include "fft.h" +#include "psycho_1.h" +#include "psycho_1_priv.h" + +#define DBTAB 1000 +double dbtable[DBTAB]; + +/********************************************************************** + + This module implements the psychoacoustic model I for the + MPEG encoder layer II. It uses simplified tonal and noise masking + threshold analysis to generate SMR for the encoder bit allocation + routine. + +**********************************************************************/ + +void psycho_1 (short buffer[2][1152], double scale[2][SBLIMIT], + double ltmin[2][SBLIMIT], frame_info * frame) +{ + frame_header *header = frame->header; + int nch = frame->nch; + int sblimit = frame->sblimit; + int k, i, tone = 0, noise = 0; + static char init = 0; + static int off[2] = { 256, 256 }; + double sample[FFT_SIZE]; + double spike[2][SBLIMIT]; + static D1408 *fft_buf; + static mask_ptr power; + static g_ptr ltg; + FLOAT energy[FFT_SIZE]; + + /* call functions for critical boundaries, freq. */ + if (!init) { /* bands, bark values, and mapping */ + fft_buf = (D1408 *) mem_alloc ((long) sizeof (D1408) * 2, "fft_buf"); + power = (mask_ptr) mem_alloc (sizeof (mask) * HAN_SIZE, "power"); + if (header->version == MPEG_AUDIO_ID) { + psycho_1_read_cbound (header->lay, header->sampling_frequency); + psycho_1_read_freq_band (<g, header->lay, header->sampling_frequency); + } else { + psycho_1_read_cbound (header->lay, header->sampling_frequency + 4); + psycho_1_read_freq_band (<g, header->lay, header->sampling_frequency + 4); + } + psycho_1_make_map (power, ltg); + for (i = 0; i < 1408; i++) + fft_buf[0][i] = fft_buf[1][i] = 0; + + psycho_1_init_add_db (); /* create the add_db table */ + + init = 1; + } + for (k = 0; k < nch; k++) { + /* check pcm input for 3 blocks of 384 samples */ + /* sami's speedup, added in 02j + saves about 4% overall during an encode */ + int ok = off[k] % 1408; + for (i = 0; i < 1152; i++) { + fft_buf[k][ok++] = (double) buffer[k][i] / SCALE; + if (ok >= 1408) + ok = 0; + } + ok = (off[k] + 1216) % 1408; + for (i = 0; i < FFT_SIZE; i++) { + sample[i] = fft_buf[k][ok++]; + if (ok >= 1408) + ok = 0; + } + off[k] += 1152; + off[k] %= 1408; + + psycho_1_hann_fft_pickmax (sample, power, &spike[k][0], energy); + psycho_1_tonal_label (power, &tone); + psycho_1_noise_label (power, &noise, ltg, energy); + //psycho_1_dump(power, &tone, &noise) ; + psycho_1_subsampling (power, ltg, &tone, &noise); + psycho_1_threshold (power, ltg, &tone, &noise, + bitrate[header->version][header->bitrate_index] / nch); + psycho_1_minimum_mask (ltg, <min[k][0], sblimit); + psycho_1_smr (<min[k][0], &spike[k][0], &scale[k][0], sblimit); + } + +} + + +int crit_band; +int *cbound; +int sub_size; + +void psycho_1_read_cbound (int lay, int freq) +/* this function reads in critical band boundaries */ +{ + +#include "critband.h" + //static const int FirstCriticalBand[7][27] = {... + + int i, k; + + if ((lay < 1) || (lay > 2)) { + printf ("Internal error (read_cbound())\n"); + return; + } + if ((freq < 0) || (freq > 6) || (freq == 3)) { + printf ("Internal error (read_cbound())\n"); + return; + } + + crit_band = SecondCriticalBand[freq][0]; + cbound = (int *) mem_alloc (sizeof (int) * crit_band, "cbound"); + for (i = 0; i < crit_band; i++) { + k = SecondCriticalBand[freq][i + 1]; + if (k != 0) { + cbound[i] = k; + } else { + printf ("Internal error (read_cbound())\n"); + return; + } + } +} + +void psycho_1_read_freq_band (ltg, lay, freq) /* this function reads in */ + int lay, freq; /* frequency bands and bark */ + g_ptr *ltg; /* values */ +{ + +#include "freqtable.h" + + int i, k; + + if ((freq < 0) || (freq > 6) || (freq == 3)) { + printf ("Internal error (read_freq_band())\n"); + return; + } + + /* read input for freq. subbands */ + + sub_size = SecondFreqEntries[freq] + 1; + *ltg = (g_ptr) mem_alloc (sizeof (g_thres) * sub_size, "ltg"); + (*ltg)[0].line = 0; /* initialize global masking threshold */ + (*ltg)[0].bark = 0.0; + (*ltg)[0].hear = 0.0; + for (i = 1; i < sub_size; i++) { + k = SecondFreqSubband[freq][i - 1].line; + if (k != 0) { + (*ltg)[i].line = k; + (*ltg)[i].bark = SecondFreqSubband[freq][i - 1].bark; + (*ltg)[i].hear = SecondFreqSubband[freq][i - 1].hear; + } else { + printf ("Internal error (read_freq_band())\n"); + return; + } + } +} + + +void psycho_1_make_map (mask power[HAN_SIZE], g_thres * ltg) +/* this function calculates the global masking threshold */ +{ + int i, j; + + for (i = 1; i < sub_size; i++) + for (j = ltg[i - 1].line; j <= ltg[i].line; j++) + power[j].map = i; +} + +void psycho_1_init_add_db (void) +{ + int i; + double x; + for (i = 0; i < DBTAB; i++) { + x = (double) i / 10.0; + dbtable[i] = 10 * log10 (1 + pow (10.0, x / 10.0)) - x; + } +} + +double add_db (double a, double b) +{ + /* MFC - if the difference between a and b is large (>99), then just return the + largest one. (about 10% of the time) + - For differences between 0 and 99, return the largest value, but add + in a pre-calculated difference value. + - the value 99 was chosen arbitarily. + - maximum (a-b) i've seen is 572 */ + FLOAT fdiff; + int idiff; + fdiff = (10.0 * (a - b)); + + if (fdiff > 990.0) { + return a; + } + if (fdiff < -990.0) { + return (b); + } + + idiff = (int) fdiff; + if (idiff >= 0) { + return (a + dbtable[idiff]); + } + + return (b + dbtable[-idiff]); +} + +/**************************************************************** +* Window the samples then, +* Fast Fourier transform of the input samples. +* +* ( call the FHT-based fft() in fft.c ) +* +* +****************************************************************/ +void psycho_1_hann_fft_pickmax (double sample[FFT_SIZE], mask power[HAN_SIZE], + double spike[SBLIMIT], FLOAT energy[FFT_SIZE]) +{ + FLOAT x_real[FFT_SIZE]; + register int i, j; + register double sqrt_8_over_3; + static int init = 0; + static double *window; + double sum; + + if (!init) { /* calculate window function for the Fourier transform */ + window = (double *) mem_alloc (sizeof (DFFT), "window"); + sqrt_8_over_3 = pow (8.0 / 3.0, 0.5); + for (i = 0; i < FFT_SIZE; i++) { + /* Hann window formula */ + window[i] = + sqrt_8_over_3 * 0.5 * (1 - + cos (2.0 * PI * i / (FFT_SIZE))) / FFT_SIZE; + } + init = 1; + } + for (i = 0; i < FFT_SIZE; i++) + x_real[i] = (FLOAT) (sample[i] * window[i]); + + psycho_1_fft (x_real, energy, FFT_SIZE); + + for (i = 0; i < HAN_SIZE; i++) { /* calculate power density spectrum */ + if (energy[i] < 1E-20) + power[i].x = -200.0 + POWERNORM; + else + power[i].x = 10 * log10 (energy[i]) + POWERNORM; + power[i].next = STOP; + power[i].type = FALSE; + } + + /* Calculate the sum of spectral component in each subband from bound 4-16 */ + +#define CF 1073741824 /* pow(10, 0.1*POWERNORM) */ +#define DBM 1E-20 /* pow(10.0, 0.1*DBMIN */ + for (i = 0; i < HAN_SIZE; spike[i >> 4] = 10.0 * log10 (sum), i += 16) { + for (j = 0, sum = DBM; j < 16; j++) + sum += CF * energy[i + j]; + } +} + +/**************************************************************** +* +* This function labels the tonal component in the power +* spectrum. +* +****************************************************************/ + +void psycho_1_tonal_label (mask power[HAN_SIZE], int *tone) +/* this function extracts (tonal) sinusoidals from the spectrum */ +{ + int i, j, last = LAST, first, run, last_but_one = LAST; /* dpwe */ + double max; + + *tone = LAST; + for (i = 2; i < HAN_SIZE - 12; i++) { + if (power[i].x > power[i - 1].x && power[i].x >= power[i + 1].x) { + power[i].type = TONE; + power[i].next = LAST; + if (last != LAST) + power[last].next = i; + else + first = *tone = i; + last = i; + } + } + last = LAST; + first = *tone; + *tone = LAST; + while ((first != LAST) && (first != STOP)) { /* the conditions for the tonal */ + if (first < 3 || first > 500) + run = 0; /* otherwise k+/-j will be out of bounds */ + else if (first < 63) + run = 2; /* components in layer II, which */ + else if (first < 127) + run = 3; /* are the boundaries for calc. */ + else if (first < 255) + run = 6; /* the tonal components */ + else + run = 12; + max = power[first].x - 7; /* after calculation of tonal */ + for (j = 2; j <= run; j++) /* components, set to local max */ + if (max < power[first - j].x || max < power[first + j].x) { + power[first].type = FALSE; + break; + } + if (power[first].type == TONE) { /* extract tonal components */ + int help = first; + if (*tone == LAST) + *tone = first; + while ((power[help].next != LAST) && (power[help].next - first) <= run) + help = power[help].next; + help = power[help].next; + power[first].next = help; + if ((first - last) <= run) { + if (last_but_one != LAST) + power[last_but_one].next = first; + } + if (first > 1 && first < 500) { /* calculate the sum of the */ + double tmp; /* powers of the components */ + tmp = add_db (power[first - 1].x, power[first + 1].x); + power[first].x = add_db (power[first].x, tmp); + } + for (j = 1; j <= run; j++) { + power[first - j].x = power[first + j].x = DBMIN; + power[first - j].next = power[first + j].next = STOP; + power[first - j].type = power[first + j].type = FALSE; + } + last_but_one = last; + last = first; + first = power[first].next; + } else { + int ll; + if (last == LAST); /* *tone = power[first].next; dpwe */ + else + power[last].next = power[first].next; + ll = first; + first = power[first].next; + power[ll].next = STOP; + } + } +} + +/**************************************************************** +* +* This function groups all the remaining non-tonal +* spectral lines into critical band where they are replaced by +* one single line. +* +****************************************************************/ + +void psycho_1_noise_label (mask * power, int *noise, g_thres * ltg, + FLOAT energy[FFT_SIZE]) +{ + int i, j, centre, last = LAST; + double index, weight, sum; + /* calculate the remaining spectral */ + for (i = 0; i < crit_band - 1; i++) { /* lines for non-tonal components */ + for (j = cbound[i], weight = 0.0, sum = DBMIN; j < cbound[i + 1]; j++) { + if (power[j].type != TONE) { + if (power[j].x != DBMIN) { + sum = add_db (power[j].x, sum); + /* Weight is used in finding the geometric mean of the noise energy within a subband */ + weight += CF * energy[j] * (double) (j - cbound[i]) / (double) (cbound[i + 1] - cbound[i]); /* correction */ + power[j].x = DBMIN; + } + } /* check to see if the spectral line is low dB, and if */ + } /* so replace the center of the critical band, which is */ + /* the center freq. of the noise component */ + + if (sum <= DBMIN) + centre = (cbound[i + 1] + cbound[i]) / 2; + else { + /* fprintf(stderr, "%i [%f %f] -", count++,weight/pow(10.0,0.1*sum), weight*pow(10.0,-0.1*sum)); */ + index = weight * pow (10.0, -0.1 * sum); + centre = + cbound[i] + (int) (index * (double) (cbound[i + 1] - cbound[i])); + } + + + /* locate next non-tonal component until finished; */ + /* add to list of non-tonal components */ + + /* Masahiro Iwadare's fix for infinite looping problem? */ + if (power[centre].type == TONE) { + if (power[centre + 1].type == TONE) { + centre++; + } else + centre--; + } + + if (last == LAST) + *noise = centre; + else { + power[centre].next = LAST; + power[last].next = centre; + } + power[centre].x = sum; + power[centre].type = NOISE; + last = centre; + } +} + +/**************************************************************** +* +* This function reduces the number of noise and tonal +* component for further threshold analysis. +* +****************************************************************/ + +void psycho_1_subsampling (mask power[HAN_SIZE], g_thres * ltg, int *tone, int *noise) +{ + int i, old; + + i = *tone; + old = STOP; /* calculate tonal components for */ + + while ((i != LAST) && (i != STOP)) + { /* reduction of spectral lines */ + if (power[i].x < ltg[power[i].map].hear) { + power[i].type = FALSE; + power[i].x = DBMIN; + if (old == STOP) + *tone = power[i].next; + else + power[old].next = power[i].next; + } else + old = i; + i = power[i].next; + } + i = *noise; + old = STOP; /* calculate non-tonal components for */ + while ((i != LAST) && (i != STOP)) { /* reduction of spectral lines */ + if (power[i].x < ltg[power[i].map].hear) { + power[i].type = FALSE; + power[i].x = DBMIN; + if (old == STOP) + *noise = power[i].next; + else + power[old].next = power[i].next; + } else + old = i; + i = power[i].next; + } + i = *tone; + old = STOP; + while ((i != LAST) && (i != STOP)) + { /* if more than one */ + if (power[i].next == LAST) + break; /* tonal component */ + if (ltg[power[power[i].next].map].bark - /* is less than .5 */ + ltg[power[i].map].bark < 0.5) { /* bark, take the */ + if (power[power[i].next].x > power[i].x) { /* maximum */ + if (old == STOP) + *tone = power[i].next; + else + power[old].next = power[i].next; + power[i].type = FALSE; + power[i].x = DBMIN; + i = power[i].next; + } else { + power[power[i].next].type = FALSE; + power[power[i].next].x = DBMIN; + power[i].next = power[power[i].next].next; + old = i; + } + } else { + old = i; + i = power[i].next; + } + } +} + +/**************************************************************** +* +* This function calculates the individual threshold and +* sum with the quiet threshold to find the global threshold. +* +****************************************************************/ + +/* mainly just changed the way range checking was done MFC Nov 1999 */ +void psycho_1_threshold (mask power[HAN_SIZE], g_thres * ltg, int *tone, int *noise, + int bit_rate) +{ + int k, t; + double dz, tmps, vf; + + for (k = 1; k < sub_size; k++) { + ltg[k].x = DBMIN; + t = *tone; /* calculate individual masking threshold for */ + while ((t != LAST) && (t != STOP)) + { /* components in order to find the global */ + dz = ltg[k].bark - ltg[power[t].map].bark; /* distance of bark value */ + if (dz >= -3.0 && dz < 8.0) { + tmps = -1.525 - 0.275 * ltg[power[t].map].bark - 4.5 + power[t].x; + /* masking function for lower & upper slopes */ + if (dz < -1) + vf = 17 * (dz + 1) - (0.4 * power[t].x + 6); + else if (dz < 0) + vf = (0.4 * power[t].x + 6) * dz; + else if (dz < 1) + vf = (-17 * dz); + else + vf = -(dz - 1) * (17 - 0.15 * power[t].x) - 17; + ltg[k].x = add_db (ltg[k].x, tmps + vf); + } + t = power[t].next; + } + + t = *noise; /* calculate individual masking threshold */ + while ((t != LAST) && (t != STOP)) { /* for non-tonal components to find LTG */ + dz = ltg[k].bark - ltg[power[t].map].bark; /* distance of bark value */ + if (dz >= -3.0 && dz < 8.0) { + tmps = -1.525 - 0.175 * ltg[power[t].map].bark - 0.5 + power[t].x; + /* masking function for lower & upper slopes */ + if (dz < -1) + vf = 17 * (dz + 1) - (0.4 * power[t].x + 6); + else if (dz < 0) + vf = (0.4 * power[t].x + 6) * dz; + else if (dz < 1) + vf = (-17 * dz); + else + vf = -(dz - 1) * (17 - 0.15 * power[t].x) - 17; + ltg[k].x = add_db (ltg[k].x, tmps + vf); + } + t = power[t].next; + } + if (bit_rate < 96) + ltg[k].x = add_db (ltg[k].hear, ltg[k].x); + else + ltg[k].x = add_db (ltg[k].hear - 12.0, ltg[k].x); + } + +} + +/**************************************************************** +* +* This function finds the minimum masking threshold and +* return the value to the encoder. +* +****************************************************************/ + +void psycho_1_minimum_mask (g_thres * ltg, double ltmin[SBLIMIT], int sblimit) +{ + double min; + int i, j; + + j = 1; + for (i = 0; i < sblimit; i++) + if (j >= sub_size - 1) /* check subband limit, and */ + ltmin[i] = ltg[sub_size - 1].hear; /* calculate the minimum masking */ + else { /* level of LTMIN for each subband */ + min = ltg[j].x; + while (ltg[j].line >> 4 == i && j < sub_size) { + if (min > ltg[j].x) + min = ltg[j].x; + j++; + } + ltmin[i] = min; + } +} + +/***************************************************************** +* +* This procedure is called in musicin to pick out the +* smaller of the scalefactor or threshold. +* +*****************************************************************/ + +void psycho_1_smr (double ltmin[SBLIMIT], double spike[SBLIMIT], double scale[SBLIMIT], + int sblimit) +{ + int i; + double max; + + for (i = 0; i < sblimit; i++) { /* determine the signal */ + max = 20 * log10 (scale[i] * 32768) - 10; /* level for each subband */ + if (spike[i] > max) + max = spike[i]; /* for the maximum scale */ + max -= ltmin[i]; /* factors */ + ltmin[i] = max; + } +} + +void psycho_1_dump(mask power[HAN_SIZE], int *tone, int *noise) { + int t; + + fprintf(stdout,"1 Ton: "); + t=*tone; + while (t!=LAST && t!=STOP) { + fprintf(stdout,"[%i] %3.0f ",t, power[t].x); + t = power[t].next; + } + fprintf(stdout,"\n"); + + fprintf(stdout,"1 Nos: "); + t=*noise; + while (t!=LAST && t!=STOP) { + fprintf(stdout,"[%i] %3.0f ",t, power[t].x); + t = power[t].next; + } + fprintf(stdout,"\n"); +} |