ref: 883355a95bec272ec70686f24f245aac9c43614d
parent: e7c9036d2c72450694cf18ae6bbf8f4fa84200b5
author: knik <knik>
date: Sat Nov 23 12:33:28 EST 2002
noise threshold updated to fit new quantizer improved block type switch
--- a/libfaac/psychkni.c
+++ b/libfaac/psychkni.c
@@ -16,7 +16,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
- * $Id: psychkni.c,v 1.2 2002/08/21 16:54:55 knik Exp $
+ * $Id: psychkni.c,v 1.3 2002/11/23 17:33:28 knik Exp $
*/
#include <stdio.h>
#include <stdlib.h>
@@ -74,34 +74,47 @@
int num_cb_long, int *cb_width_short, int num_cb_short)
{int b, j;
- double enb[8][NSFB_SHORT]; // total energy in each band in each window
- double enchg[NSFB_SHORT]; // energy change
+ double volb[8][NSFB_SHORT]; // band volume in each window
double totchg;
int lastband;
+ int offset;
psydata_t *psydata = psyInfo->data;
+ const double globalthr = 70;
+ double tmp;
+ double thr;
/* Long window */
+ offset = 1;
for (b = 0; b < num_cb_long; b++)
{- psyInfo->maskThr[b] = 0.8;
+ tmp = (double)(offset + cb_width_long[b]) / offset;
+
+ thr = log(tmp) * globalthr;
+
psyInfo->maskEn[b] = 1.0;
- // extremely simple constant masking threshold
- // but it works better than those elaborate but buggy models >:)
+ psyInfo->maskThr[b] = 1.0 / thr;
+ offset += cb_width_long[b];
}
/* Short windows */
+ offset = 1;
for (j = 0; j < 8; j++)
{for (b = 0; b < num_cb_short; b++)
{- psyInfo->maskThrS[j][b] = 0.5;
+ tmp = (double)(offset + cb_width_short[b]) / offset;
+
+ thr = log(tmp) * globalthr;
+
psyInfo->maskEnS[j][b] = 1.0;
+ psyInfo->maskThrS[j][b] = 1.0 / thr;
+ offset += cb_width_short[b];
}
}
/* long/short block switch */
- // compute energy
+ // compute band volume
for (j = 0; j < 8; j++)
{int l = 0;
@@ -109,43 +122,44 @@
{int last = l + cb_width_short[b];
double e = 0;
+
+ if (last > psydata->bandS) // band out of range
+ {+ volb[j][b] = 0;
+ l = last;
+ continue;
+ }
+
for (; l < last; l++)
e += psydata->fftEnrgS[j][l];
-
- if (l >= psydata->bandS)
- break;
- enb[j][b] = e;
- //printf("en[%d][%d] = %g\n", j, b, e);+ volb[j][b] = sqrt(e);
}
}
lastband = b;
- // compare levels of energy in each band of short widows
+ // compare volume levels in each band of short widows
totchg = 0.0;
for (b = 2; b < lastband; b++)
{double maxdif = 0;
- enchg[b] = 0.0;
for (j = 1; j < 7; j++)
{- double slowen = (1.0 / 7.0) * ((7 - j) * enb[0][b] + j * enb[7][b]);
- double endif = enb[j][b] - slowen;
+ double slowvol = (1.0 / 7.0) * ((7 - j) * volb[0][b] + j * volb[7][b]);
+ double voldif = volb[j][b] / slowvol;
- endif /= enb[j][b];
+ if (voldif < 1.0)
+ voldif = 1.0 / voldif;
+ voldif -= 1.0;
- if (endif < 0)
- endif = -endif;
- if (endif > maxdif)
- maxdif = endif;
+ if (voldif > maxdif)
+ maxdif = voldif;
}
- enchg[b] += maxdif;
- totchg += enchg[b];
- //printf("enchg[%d] = %g\n", b, enchg[b]);+ totchg += maxdif;
}
totchg = totchg / lastband;
- psyInfo->block_type = (totchg > 3.0) ? ONLY_SHORT_WINDOW : ONLY_LONG_WINDOW;
+ psyInfo->block_type = (totchg > 1.0) ? ONLY_SHORT_WINDOW : ONLY_LONG_WINDOW;
#if 0
printf("totchg: %s %g\n", (psyInfo->block_type == ONLY_SHORT_WINDOW)@@ -403,8 +417,8 @@
{int i, j;
double a, b;
- static double transBuff[2 * BLOCK_LEN_LONG];
- static double transBuffS[2 * BLOCK_LEN_SHORT];
+ double transBuff[2 * BLOCK_LEN_LONG];
+ double transBuffS[2 * BLOCK_LEN_SHORT];
psydata_t *psydata = psyInfo->data;
psyfloat *tmp;