ref: 09ad6d02e8976f54aaf711c7ebacb57b8d81de1a
dir: /libfaac/psychkni.c/
/*
* FAAC - Freeware Advanced Audio Coder
* Copyright (C) 2002 Krzysztof Nikiel
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: psychkni.c,v 1.17 2005/04/24 19:16:14 rjamorim Exp $
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "psych.h"
#include "coder.h"
#include "fft.h"
#include "util.h"
#include "frame.h"
typedef float psyfloat;
typedef struct
{
/* bandwidth */
int bandS;
int lastband;
/* SFB energy */
psyfloat *fftEnrgS[8];
psyfloat *fftEnrgNextS[8];
psyfloat *fftEnrgNext2S[8];
psyfloat *fftEnrgPrevS[8];
}
psydata_t;
static void Hann(GlobalPsyInfo * gpsyInfo, double *inSamples, int size)
{
int i;
/* Applying Hann window */
if (size == BLOCK_LEN_LONG * 2)
{
for (i = 0; i < size; i++)
inSamples[i] *= gpsyInfo->hannWindow[i];
}
else
{
for (i = 0; i < size; i++)
inSamples[i] *= gpsyInfo->hannWindowS[i];
}
}
static void PsyCheckShort(PsyInfo * psyInfo)
{
double totvol = 0.0;
double totchg, totchg2;
psydata_t *psydata = psyInfo->data;
int lastband = psydata->lastband;
int firstband = 1;
int sfb;
/* long/short block switch */
totchg = totchg2 = 0.0;
for (sfb = 0; sfb < lastband; sfb++)
{
int win;
double volb[16];
double vavg[13];
double maxdif = 0.0;
double totmaxdif = 0.0;
double e, v;
// previous frame
for (win = 0; win < 4; win++)
{
e = psydata->fftEnrgPrevS[win + 4][sfb];
volb[win] = sqrt(e);
totvol += e;
}
// current frame
for (win = 0; win < 8; win++)
{
e = psydata->fftEnrgS[win][sfb];
volb[win + 4] = sqrt(e);
totvol += e;
}
// next frame
for (win = 0; win < 4; win++)
{
e = psydata->fftEnrgNextS[win][sfb];
volb[win + 12] = sqrt(e);
totvol += e;
}
// ignore lowest SFBs
if (sfb < firstband)
continue;
v = 0.0;
for (win = 0; win < 4; win++)
{
v += volb[win];
}
vavg[0] = 0.25 * v;
for (win = 1; win < 13; win++)
{
v -= volb[win - 1];
v += volb[win + 3];
vavg[win] = 0.25 * v;
}
for (win = 0; win < 8; win++)
{
int i;
double mina, maxv;
double voldif;
double totvoldif;
mina = vavg[win];
for (i = 1; i < 5; i++)
mina = min(mina, vavg[win + i]);
maxv = volb[win + 2];
for (i = 3; i < 6; i++)
maxv = max(maxv, volb[win + i]);
if (!maxv || !mina)
continue;
voldif = (maxv - mina) / mina;
totvoldif = (maxv - mina) * (maxv - mina);
if (voldif > maxdif)
maxdif = voldif;
if (totvoldif > totmaxdif)
totmaxdif = totvoldif;
}
totchg += maxdif;
totchg2 += totmaxdif;
}
totvol = sqrt(totvol);
totchg2 = sqrt(totchg2);
totchg = totchg / lastband;
if (totvol)
totchg2 /= totvol;
else
totchg2 = 0.0;
psyInfo->block_type = ((totchg > 1.0) && (totchg2 > 0.04))
? ONLY_SHORT_WINDOW : ONLY_LONG_WINDOW;
#if 0
{
static int total = 0, shorts = 0;
char *flash = " ";
total++;
if (psyInfo->block_type == ONLY_SHORT_WINDOW)
{
flash = "****";
shorts++;
}
printf("totchg: %s %g %g\t%g\n", flash, totchg, totchg2,
(double)shorts/total);
}
#endif
}
static void PsyInit(GlobalPsyInfo * gpsyInfo, PsyInfo * psyInfo, unsigned int numChannels,
unsigned int sampleRate, int *cb_width_long, int num_cb_long,
int *cb_width_short, int num_cb_short)
{
unsigned int channel;
int i, j, size;
gpsyInfo->hannWindow =
(double *) AllocMemory(2 * BLOCK_LEN_LONG * sizeof(double));
gpsyInfo->hannWindowS =
(double *) AllocMemory(2 * BLOCK_LEN_SHORT * sizeof(double));
for (i = 0; i < BLOCK_LEN_LONG * 2; i++)
gpsyInfo->hannWindow[i] = 0.5 * (1 - cos(2.0 * M_PI * (i + 0.5) /
(BLOCK_LEN_LONG * 2)));
for (i = 0; i < BLOCK_LEN_SHORT * 2; i++)
gpsyInfo->hannWindowS[i] = 0.5 * (1 - cos(2.0 * M_PI * (i + 0.5) /
(BLOCK_LEN_SHORT * 2)));
gpsyInfo->sampleRate = (double) sampleRate;
for (channel = 0; channel < numChannels; channel++)
{
psydata_t *psydata = AllocMemory(sizeof(psydata_t));
psyInfo[channel].data = psydata;
}
size = BLOCK_LEN_LONG;
for (channel = 0; channel < numChannels; channel++)
{
psyInfo[channel].size = size;
psyInfo[channel].prevSamples =
(double *) AllocMemory(size * sizeof(double));
memset(psyInfo[channel].prevSamples, 0, size * sizeof(double));
}
size = BLOCK_LEN_SHORT;
for (channel = 0; channel < numChannels; channel++)
{
psydata_t *psydata = psyInfo[channel].data;
psyInfo[channel].sizeS = size;
psyInfo[channel].prevSamplesS =
(double *) AllocMemory(size * sizeof(double));
memset(psyInfo[channel].prevSamplesS, 0, size * sizeof(double));
for (j = 0; j < 8; j++)
{
psydata->fftEnrgPrevS[j] =
(psyfloat *) AllocMemory(NSFB_SHORT * sizeof(psyfloat));
memset(psydata->fftEnrgPrevS[j], 0, NSFB_SHORT * sizeof(psyfloat));
psydata->fftEnrgS[j] =
(psyfloat *) AllocMemory(NSFB_SHORT * sizeof(psyfloat));
memset(psydata->fftEnrgS[j], 0, NSFB_SHORT * sizeof(psyfloat));
psydata->fftEnrgNextS[j] =
(psyfloat *) AllocMemory(NSFB_SHORT * sizeof(psyfloat));
memset(psydata->fftEnrgNextS[j], 0, NSFB_SHORT * sizeof(psyfloat));
psydata->fftEnrgNext2S[j] =
(psyfloat *) AllocMemory(NSFB_SHORT * sizeof(psyfloat));
memset(psydata->fftEnrgNext2S[j], 0, NSFB_SHORT * sizeof(psyfloat));
}
}
}
static void PsyEnd(GlobalPsyInfo * gpsyInfo, PsyInfo * psyInfo, unsigned int numChannels)
{
unsigned int channel;
int j;
if (gpsyInfo->hannWindow)
FreeMemory(gpsyInfo->hannWindow);
if (gpsyInfo->hannWindowS)
FreeMemory(gpsyInfo->hannWindowS);
for (channel = 0; channel < numChannels; channel++)
{
if (psyInfo[channel].prevSamples)
FreeMemory(psyInfo[channel].prevSamples);
}
for (channel = 0; channel < numChannels; channel++)
{
psydata_t *psydata = psyInfo[channel].data;
if (psyInfo[channel].prevSamplesS)
FreeMemory(psyInfo[channel].prevSamplesS);
for (j = 0; j < 8; j++)
{
if (psydata->fftEnrgPrevS[j])
FreeMemory(psydata->fftEnrgPrevS[j]);
if (psydata->fftEnrgS[j])
FreeMemory(psydata->fftEnrgS[j]);
if (psydata->fftEnrgNextS[j])
FreeMemory(psydata->fftEnrgNextS[j]);
if (psydata->fftEnrgNext2S[j])
FreeMemory(psydata->fftEnrgNext2S[j]);
}
}
for (channel = 0; channel < numChannels; channel++)
{
if (psyInfo[channel].data)
FreeMemory(psyInfo[channel].data);
}
}
/* Do psychoacoustical analysis */
static void PsyCalculate(ChannelInfo * channelInfo, GlobalPsyInfo * gpsyInfo,
PsyInfo * psyInfo, int *cb_width_long, int
num_cb_long, int *cb_width_short,
int num_cb_short, unsigned int numChannels)
{
unsigned int channel;
for (channel = 0; channel < numChannels; channel++)
{
if (channelInfo[channel].present)
{
if (channelInfo[channel].cpe &&
channelInfo[channel].ch_is_left)
{ /* CPE */
int leftChan = channel;
int rightChan = channelInfo[channel].paired_ch;
PsyCheckShort(&psyInfo[leftChan]);
PsyCheckShort(&psyInfo[rightChan]);
}
else if (!channelInfo[channel].cpe &&
channelInfo[channel].lfe)
{ /* LFE */
// Only set block type and it should be OK
psyInfo[channel].block_type = ONLY_LONG_WINDOW;
}
else if (!channelInfo[channel].cpe)
{ /* SCE */
PsyCheckShort(&psyInfo[channel]);
}
}
}
}
static void PsyBufferUpdate( FFT_Tables *fft_tables, GlobalPsyInfo * gpsyInfo, PsyInfo * psyInfo,
double *newSamples, unsigned int bandwidth,
int *cb_width_short, int num_cb_short)
{
int win;
double transBuff[2 * BLOCK_LEN_LONG];
double transBuffS[2 * BLOCK_LEN_SHORT];
psydata_t *psydata = psyInfo->data;
psyfloat *tmp;
int sfb;
psydata->bandS = psyInfo->sizeS * bandwidth * 2 / gpsyInfo->sampleRate;
memcpy(transBuff, psyInfo->prevSamples, psyInfo->size * sizeof(double));
memcpy(transBuff + psyInfo->size, newSamples, psyInfo->size * sizeof(double));
for (win = 0; win < 8; win++)
{
int first = 0;
int last = 0;
memcpy(transBuffS, transBuff + (win * BLOCK_LEN_SHORT) + (BLOCK_LEN_LONG - BLOCK_LEN_SHORT) / 2,
2 * psyInfo->sizeS * sizeof(double));
Hann(gpsyInfo, transBuffS, 2 * psyInfo->sizeS);
rfft( fft_tables, transBuffS, 8);
// shift bufs
tmp = psydata->fftEnrgPrevS[win];
psydata->fftEnrgPrevS[win] = psydata->fftEnrgS[win];
psydata->fftEnrgS[win] = psydata->fftEnrgNextS[win];
psydata->fftEnrgNextS[win] = psydata->fftEnrgNext2S[win];
psydata->fftEnrgNext2S[win] = tmp;
for (sfb = 0; sfb < num_cb_short; sfb++)
{
double e;
int l;
first = last;
last = first + cb_width_short[sfb];
if (first < 1)
first = 1;
//if (last > psydata->bandS) // band out of range
if (first >= psydata->bandS) // band out of range
break;
e = 0.0;
for (l = first; l < last; l++)
{
double a = transBuffS[l];
double b = transBuffS[l + psyInfo->sizeS];
e += a * a + b * b;
}
psydata->fftEnrgNext2S[win][sfb] = e;
}
psydata->lastband = sfb;
for (; sfb < num_cb_short; sfb++)
{
psydata->fftEnrgNext2S[win][sfb] = 0;
}
}
memcpy(psyInfo->prevSamples, newSamples, psyInfo->size * sizeof(double));
}
static void BlockSwitch(CoderInfo * coderInfo, PsyInfo * psyInfo, unsigned int numChannels)
{
unsigned int channel;
int desire = ONLY_LONG_WINDOW;
/* Use the same block type for all channels
If there is 1 channel that wants a short block,
use a short block on all channels.
*/
for (channel = 0; channel < numChannels; channel++)
{
if (psyInfo[channel].block_type == ONLY_SHORT_WINDOW)
desire = ONLY_SHORT_WINDOW;
}
for (channel = 0; channel < numChannels; channel++)
{
int lasttype = coderInfo[channel].block_type;
if (desire == ONLY_SHORT_WINDOW
|| coderInfo[channel].desired_block_type == ONLY_SHORT_WINDOW)
{
if (lasttype == ONLY_LONG_WINDOW || lasttype == SHORT_LONG_WINDOW)
coderInfo[channel].block_type = LONG_SHORT_WINDOW;
else
coderInfo[channel].block_type = ONLY_SHORT_WINDOW;
}
else
{
if (lasttype == ONLY_SHORT_WINDOW || lasttype == LONG_SHORT_WINDOW)
coderInfo[channel].block_type = SHORT_LONG_WINDOW;
else
coderInfo[channel].block_type = ONLY_LONG_WINDOW;
}
coderInfo[channel].desired_block_type = desire;
}
}
psymodel_t psymodel2 =
{
PsyInit,
PsyEnd,
PsyCalculate,
PsyBufferUpdate,
BlockSwitch
};