annotate src/lag_wind.c @ 8:8b17df8f6340 default tip

add README
author Mychaela Falconia <falcon@freecalypso.org>
date Wed, 17 Apr 2024 17:30:25 +0000
parents 56410792419a
children
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
0
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
1 /*************************************************************************
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
2 *
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
3 * FUNCTION: Lag_window()
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
4 *
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
5 * PURPOSE: Lag windowing of autocorrelations.
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
6 *
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
7 * DESCRIPTION:
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
8 * r[i] = r[i]*lag_wind[i], i=1,...,10
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
9 *
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
10 * r[i] and lag_wind[i] are in special double precision format.
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
11 * See "oper_32b.c" for the format.
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
12 *
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
13 *************************************************************************/
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
14
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
15 #include "typedef.h"
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
16 #include "basic_op.h"
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
17 #include "oper_32b.h"
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
18 #include "count.h"
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
19
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
20 #include "lag_wind.tab"
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
21
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
22 void Lag_window (
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
23 Word16 m, /* (i) : LPC order */
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
24 Word16 r_h[], /* (i/o) : Autocorrelations (msb) */
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
25 Word16 r_l[] /* (i/o) : Autocorrelations (lsb) */
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
26 )
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
27 {
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
28 Word16 i;
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
29 Word32 x;
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
30
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
31 for (i = 1; i <= m; i++)
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
32 {
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
33 x = Mpy_32 (r_h[i], r_l[i], lag_h[i - 1], lag_l[i - 1]);
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
34 L_Extract (x, &r_h[i], &r_l[i]);
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
35 }
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
36 return;
56410792419a src: original EFR source from ETSI
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
37 }