package net.sourceforge.jaad.aac.sbr;
import java.util.Arrays;
import net.sourceforge.jaad.aac.SampleFrequency;
/**
* This class is part of JAAD ( jaadec.sourceforge.net ) that is distributed
* under the Public Domain license. Code changes provided by the JCodec project
* are distributed under FreeBSD license.
*
* @author in-somnia
*/
class FBT implements SBRConstants {
/* calculate the start QMF channel for the master frequency band table */
/* parameter is also called k0 */
public static int qmf_start_channel(int bs_start_freq, int bs_samplerate_mode,
SampleFrequency sample_rate) {
int startMin = startMinTable[sample_rate.getIndex()];
int offsetIndex = offsetIndexTable[sample_rate.getIndex()];
if(bs_samplerate_mode!=0) {
return startMin+OFFSET[offsetIndex][bs_start_freq];
}
else {
return startMin+OFFSET[6][bs_start_freq];
}
}
private static final int[] stopMinTable = {13, 15, 20, 21, 23,
32, 32, 35, 48, 64, 70, 96};
private static final int[][] STOP_OFFSET_TABLE = {
{0, 2, 4, 6, 8, 11, 14, 18, 22, 26, 31, 37, 44, 51},
{0, 2, 4, 6, 8, 11, 14, 18, 22, 26, 31, 36, 42, 49},
{0, 2, 4, 6, 8, 11, 14, 17, 21, 25, 29, 34, 39, 44},
{0, 2, 4, 6, 8, 11, 14, 17, 20, 24, 28, 33, 38, 43},
{0, 2, 4, 6, 8, 11, 14, 17, 20, 24, 28, 32, 36, 41},
{0, 2, 4, 6, 8, 10, 12, 14, 17, 20, 23, 26, 29, 32},
{0, 2, 4, 6, 8, 10, 12, 14, 17, 20, 23, 26, 29, 32},
{0, 1, 3, 5, 7, 9, 11, 13, 15, 17, 20, 23, 26, 29},
{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16},
{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
{0, -1, -2, -3, -4, -5, -6, -6, -6, -6, -6, -6, -6, -6},
{0, -3, -6, -9, -12, -15, -18, -20, -22, -24, -26, -28, -30, -32}
};
/* calculate the stop QMF channel for the master frequency band table */
/* parameter is also called k2 */
public static int qmf_stop_channel(int bs_stop_freq, SampleFrequency sample_rate,
int k0) {
if(bs_stop_freq==15) {
return Math.min(64, k0*3);
}
else if(bs_stop_freq==14) {
return Math.min(64, k0*2);
}
else {
int stopMin = stopMinTable[sample_rate.getIndex()];
/* bs_stop_freq <= 13 */
return Math.min(64, stopMin+STOP_OFFSET_TABLE[sample_rate.getIndex()][Math.min(bs_stop_freq, 13)]);
}
}
/* calculate the master frequency table from k0, k2, bs_freq_scale
and bs_alter_scale
version for bs_freq_scale = 0
*/
public static int master_frequency_table_fs0(SBR sbr, int k0, int k2,
boolean bs_alter_scale) {
int incr;
int k;
int dk;
int nrBands, k2Achieved;
int k2Diff;
int[] vDk = new int[64];
/* mft only defined for k2 > k0 */
if(k2<=k0) {
sbr.N_master = 0;
return 1;
}
dk = bs_alter_scale ? 2 : 1;
if(bs_alter_scale) {
nrBands = (((k2-k0+2)>>2)<<1);
}
else {
nrBands = (((k2-k0)>>1)<<1);
}
nrBands = Math.min(nrBands, 63);
if(nrBands<=0)
return 1;
k2Achieved = k0+nrBands*dk;
k2Diff = k2-k2Achieved;
for(k = 0; k<nrBands; k++) {
vDk[k] = dk;
}
if(k2Diff!=0) {
incr = (k2Diff>0) ? -1 : 1;
k = ((k2Diff>0) ? (nrBands-1) : 0);
while(k2Diff!=0) {
vDk[k] -= incr;
k += incr;
k2Diff += incr;
}
}
sbr.f_master[0] = k0;
for(k = 1; k<=nrBands; k++) {
sbr.f_master[k] = (sbr.f_master[k-1]+vDk[k-1]);
}
sbr.N_master = nrBands;
sbr.N_master = Math.min(sbr.N_master, 64);
return 0;
}
/*
This function finds the number of bands using this formula:
bands * log(a1/a0)/log(2.0) + 0.5
*/
public static int find_bands(int warp, int bands, int a0, int a1) {
float div = (float) Math.log(2.0);
if(warp!=0) div *= 1.3f;
return (int) (bands*Math.log((float) a1/(float) a0)/div+0.5);
}
public static float find_initial_power(int bands, int a0, int a1) {
return (float) Math.pow((float) a1/(float) a0, 1.0f/(float) bands);
}
/*
version for bs_freq_scale > 0
*/
public static int master_frequency_table(SBR sbr, int k0, int k2,
int bs_freq_scale, boolean bs_alter_scale) {
int k, bands;
boolean twoRegions;
int k1;
int nrBand0, nrBand1;
int[] vDk0 = new int[64], vDk1 = new int[64];
int[] vk0 = new int[64], vk1 = new int[64];
int[] temp1 = {6, 5, 4};
float q, qk;
int A_1;
/* mft only defined for k2 > k0 */
if(k2<=k0) {
sbr.N_master = 0;
return 1;
}
bands = temp1[bs_freq_scale-1];
if((float) k2/(float) k0>2.2449) {
twoRegions = true;
k1 = k0<<1;
}
else {
twoRegions = false;
k1 = k2;
}
nrBand0 = (2*find_bands(0, bands, k0, k1));
nrBand0 = Math.min(nrBand0, 63);
if(nrBand0<=0)
return 1;
q = find_initial_power(nrBand0, k0, k1);
qk = k0;
A_1 = (int) (qk+0.5f);
for(k = 0; k<=nrBand0; k++) {
int A_0 = A_1;
qk *= q;
A_1 = (int) (qk+0.5f);
vDk0[k] = A_1-A_0;
}
/* needed? */
//qsort(vDk0, nrBand0, sizeof(vDk0[0]), longcmp);
Arrays.sort(vDk0, 0, nrBand0);
vk0[0] = k0;
for(k = 1; k<=nrBand0; k++) {
vk0[k] = vk0[k-1]+vDk0[k-1];
if(vDk0[k-1]==0)
return 1;
}
if(!twoRegions) {
for(k = 0; k<=nrBand0; k++) {
sbr.f_master[k] = vk0[k];
}
sbr.N_master = nrBand0;
sbr.N_master = Math.min(sbr.N_master, 64);
return 0;
}
nrBand1 = (2*find_bands(1 /* warped */, bands, k1, k2));
nrBand1 = Math.min(nrBand1, 63);
q = find_initial_power(nrBand1, k1, k2);
qk = k1;
A_1 = (int) (qk+0.5f);
for(k = 0; k<=nrBand1-1; k++) {
int A_0 = A_1;
qk *= q;
A_1 = (int) (qk+0.5f);
vDk1[k] = A_1-A_0;
}
if(vDk1[0]<vDk0[nrBand0-1]) {
int change;
/* needed? */
//qsort(vDk1, nrBand1+1, sizeof(vDk1[0]), longcmp);
Arrays.sort(vDk1, 0, nrBand1+1);
change = vDk0[nrBand0-1]-vDk1[0];
vDk1[0] = vDk0[nrBand0-1];
vDk1[nrBand1-1] = vDk1[nrBand1-1]-change;
}
/* needed? */
//qsort(vDk1, nrBand1, sizeof(vDk1[0]), longcmp);
Arrays.sort(vDk1, 0, nrBand1);
vk1[0] = k1;
for(k = 1; k<=nrBand1; k++) {
vk1[k] = vk1[k-1]+vDk1[k-1];
if(vDk1[k-1]==0)
return 1;
}
sbr.N_master = nrBand0+nrBand1;
sbr.N_master = Math.min(sbr.N_master, 64);
for(k = 0; k<=nrBand0; k++) {
sbr.f_master[k] = vk0[k];
}
for(k = nrBand0+1; k<=sbr.N_master; k++) {
sbr.f_master[k] = vk1[k-nrBand0];
}
return 0;
}
/* calculate the derived frequency border tables from f_master */
public static int derived_frequency_table(SBR sbr, int bs_xover_band,
int k2) {
int k, i = 0;
int minus;
/* The following relation shall be satisfied: bs_xover_band < N_Master */
if(sbr.N_master<=bs_xover_band)
return 1;
sbr.N_high = sbr.N_master-bs_xover_band;
sbr.N_low = (sbr.N_high>>1)+(sbr.N_high-((sbr.N_high>>1)<<1));
sbr.n[0] = sbr.N_low;
sbr.n[1] = sbr.N_high;
for(k = 0; k<=sbr.N_high; k++) {
sbr.f_table_res[HI_RES][k] = sbr.f_master[k+bs_xover_band];
}
sbr.M = sbr.f_table_res[HI_RES][sbr.N_high]-sbr.f_table_res[HI_RES][0];
sbr.kx = sbr.f_table_res[HI_RES][0];
if(sbr.kx>32)
return 1;
if(sbr.kx+sbr.M>64)
return 1;
minus = ((sbr.N_high&1)!=0) ? 1 : 0;
for(k = 0; k<=sbr.N_low; k++) {
if(k==0)
i = 0;
else
i = (2*k-minus);
sbr.f_table_res[LO_RES][k] = sbr.f_table_res[HI_RES][i];
}
sbr.N_Q = 0;
if(sbr.bs_noise_bands==0) {
sbr.N_Q = 1;
}
else {
sbr.N_Q = (Math.max(1, find_bands(0, sbr.bs_noise_bands, sbr.kx, k2)));
sbr.N_Q = Math.min(5, sbr.N_Q);
}
for(k = 0; k<=sbr.N_Q; k++) {
if(k==0) {
i = 0;
}
else {
/* i = i + (int32_t)((sbr.N_low - i)/(sbr.N_Q + 1 - k)); */
i += (sbr.N_low-i)/(sbr.N_Q+1-k);
}
sbr.f_table_noise[k] = sbr.f_table_res[LO_RES][i];
}
/* build table for mapping k to g in hf patching */
for(k = 0; k<64; k++) {
int g;
for(g = 0; g<sbr.N_Q; g++) {
if((sbr.f_table_noise[g]<=k)
&&(k<sbr.f_table_noise[g+1])) {
sbr.table_map_k_to_g[k] = g;
break;
}
}
}
return 0;
}
/* TODO: blegh, ugly */
/* Modified to calculate for all possible bs_limiter_bands always
* This reduces the number calls to this functions needed (now only on
* header reset)
*/
private static final float[] limiterBandsCompare = {1.327152f,
1.185093f, 1.119872f};
public static void limiter_frequency_table(SBR sbr) {
int k, s;
int nrLim;
sbr.f_table_lim[0][0] = sbr.f_table_res[LO_RES][0]-sbr.kx;
sbr.f_table_lim[0][1] = sbr.f_table_res[LO_RES][sbr.N_low]-sbr.kx;
sbr.N_L[0] = 1;
for(s = 1; s<4; s++) {
int[] limTable = new int[100 /*TODO*/];
int[] patchBorders = new int[64/*??*/];
patchBorders[0] = sbr.kx;
for(k = 1; k<=sbr.noPatches; k++) {
patchBorders[k] = patchBorders[k-1]+sbr.patchNoSubbands[k-1];
}
for(k = 0; k<=sbr.N_low; k++) {
limTable[k] = sbr.f_table_res[LO_RES][k];
}
for(k = 1; k<sbr.noPatches; k++) {
limTable[k+sbr.N_low] = patchBorders[k];
}
/* needed */
//qsort(limTable, sbr.noPatches+sbr.N_low, sizeof(limTable[0]), longcmp);
Arrays.sort(limTable, 0, sbr.noPatches+sbr.N_low);
k = 1;
nrLim = sbr.noPatches+sbr.N_low-1;
if(nrLim<0) // TODO: BIG FAT PROBLEM
return;
restart:
while(k<=nrLim) {
float nOctaves;
if(limTable[k-1]!=0)
nOctaves = (float) limTable[k]/(float) limTable[k-1];
else
nOctaves = 0;
if(nOctaves<limiterBandsCompare[s-1]) {
int i;
if(limTable[k]!=limTable[k-1]) {
boolean found = false, found2 = false;
for(i = 0; i<=sbr.noPatches; i++) {
if(limTable[k]==patchBorders[i])
found = true;
}
if(found) {
found2 = false;
for(i = 0; i<=sbr.noPatches; i++) {
if(limTable[k-1]==patchBorders[i])
found2 = true;
}
if(found2) {
k++;
continue;
}
else {
/* remove (k-1)th element */
limTable[k-1] = sbr.f_table_res[LO_RES][sbr.N_low];
//qsort(limTable, sbr.noPatches+sbr.N_low, sizeof(limTable[0]), longcmp);
Arrays.sort(limTable, 0, sbr.noPatches+sbr.N_low);
nrLim--;
continue;
}
}
}
/* remove kth element */
limTable[k] = sbr.f_table_res[LO_RES][sbr.N_low];
//qsort(limTable, nrLim, sizeof(limTable[0]), longcmp);
Arrays.sort(limTable, 0, nrLim);
nrLim--;
//continue;
}
else {
k++;
//continue;
}
}
sbr.N_L[s] = nrLim;
for(k = 0; k<=nrLim; k++) {
sbr.f_table_lim[s][k] = limTable[k]-sbr.kx;
}
}
}
}