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ref: 61f40418fab2205c94ed1f113e10677a0679baf4
parent: 49f76805ba9ee5672ba882a0152ca87bdbf0ed1e
author: Jean-Marc Valin <[email protected]>
date: Thu Jan 27 12:14:33 EST 2011 

Adjusting post-filter coefficients to be exact in 13 bit precision.

That way they can be exact in 16 bits once multiplied by the gain


--- a/libcelt/celt.c
+++ b/libcelt/celt.c
@@ -406,9 +406,9 @@
    /* printf ("%d %d %f %f\n", T0, T1, g0, g1); */
    celt_word16 g00, g01, g02, g10, g11, g12;
    static const celt_word16 gains[3][3] = {
-         {QCONST16(0.30690f, 15), QCONST16(0.21701f, 15), QCONST16(0.12954f, 15)},
-         {QCONST16(0.46410f, 15), QCONST16(0.26795f, 15), QCONST16(0.f, 15)},
-         {QCONST16(0.8f, 15),     QCONST16(0.1f, 15),     QCONST16(0.f, 15)}};
+         {QCONST16(0.3066406250f, 15), QCONST16(0.2170410156f, 15), QCONST16(0.1296386719f, 15)},
+         {QCONST16(0.4638671875f, 15), QCONST16(0.2680664062f, 15), QCONST16(0.f, 15)},
+         {QCONST16(0.7998046875f, 15), QCONST16(0.1000976562f, 15), QCONST16(0.f, 15)}};
    g00 = MULT16_16_Q15(g0, gains[tapset0][0]);
    g01 = MULT16_16_Q15(g0, gains[tapset0][1]);
    g02 = MULT16_16_Q15(g0, gains[tapset0][2]);