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authorZack Middleton <zturtleman@gmail.com>2013-02-17 18:33:39 -0600
committerTim Angus <tim@ngus.net>2013-03-19 16:41:12 +0000
commitaaf1f6659bd32e6bf5b78696512fafccacdcb7eb (patch)
tree656a77d7ea7c1238a5c594aa5be554ce11195ad4 /src/opus-1.0.2/celt/celt_lpc.c
parent5eb2ccc45d9fd9880540411e1624821c73136db6 (diff)
Add libopus 1.0.2 and libopusfile 0.2
Diffstat (limited to 'src/opus-1.0.2/celt/celt_lpc.c')
-rw-r--r--src/opus-1.0.2/celt/celt_lpc.c188
1 files changed, 188 insertions, 0 deletions
diff --git a/src/opus-1.0.2/celt/celt_lpc.c b/src/opus-1.0.2/celt/celt_lpc.c
new file mode 100644
index 00000000..d2addbf2
--- /dev/null
+++ b/src/opus-1.0.2/celt/celt_lpc.c
@@ -0,0 +1,188 @@
+/* Copyright (c) 2009-2010 Xiph.Org Foundation
+ Written by Jean-Marc Valin */
+/*
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+
+ - Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ - Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+ OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "celt_lpc.h"
+#include "stack_alloc.h"
+#include "mathops.h"
+
+void _celt_lpc(
+ opus_val16 *_lpc, /* out: [0...p-1] LPC coefficients */
+const opus_val32 *ac, /* in: [0...p] autocorrelation values */
+int p
+)
+{
+ int i, j;
+ opus_val32 r;
+ opus_val32 error = ac[0];
+#ifdef FIXED_POINT
+ opus_val32 lpc[LPC_ORDER];
+#else
+ float *lpc = _lpc;
+#endif
+
+ for (i = 0; i < p; i++)
+ lpc[i] = 0;
+ if (ac[0] != 0)
+ {
+ for (i = 0; i < p; i++) {
+ /* Sum up this iteration's reflection coefficient */
+ opus_val32 rr = 0;
+ for (j = 0; j < i; j++)
+ rr += MULT32_32_Q31(lpc[j],ac[i - j]);
+ rr += SHR32(ac[i + 1],3);
+ r = -frac_div32(SHL32(rr,3), error);
+ /* Update LPC coefficients and total error */
+ lpc[i] = SHR32(r,3);
+ for (j = 0; j < (i+1)>>1; j++)
+ {
+ opus_val32 tmp1, tmp2;
+ tmp1 = lpc[j];
+ tmp2 = lpc[i-1-j];
+ lpc[j] = tmp1 + MULT32_32_Q31(r,tmp2);
+ lpc[i-1-j] = tmp2 + MULT32_32_Q31(r,tmp1);
+ }
+
+ error = error - MULT32_32_Q31(MULT32_32_Q31(r,r),error);
+ /* Bail out once we get 30 dB gain */
+#ifdef FIXED_POINT
+ if (error<SHR32(ac[0],10))
+ break;
+#else
+ if (error<.001f*ac[0])
+ break;
+#endif
+ }
+ }
+#ifdef FIXED_POINT
+ for (i=0;i<p;i++)
+ _lpc[i] = ROUND16(lpc[i],16);
+#endif
+}
+
+void celt_fir(const opus_val16 *x,
+ const opus_val16 *num,
+ opus_val16 *y,
+ int N,
+ int ord,
+ opus_val16 *mem)
+{
+ int i,j;
+
+ for (i=0;i<N;i++)
+ {
+ opus_val32 sum = SHL32(EXTEND32(x[i]), SIG_SHIFT);
+ for (j=0;j<ord;j++)
+ {
+ sum += MULT16_16(num[j],mem[j]);
+ }
+ for (j=ord-1;j>=1;j--)
+ {
+ mem[j]=mem[j-1];
+ }
+ mem[0] = x[i];
+ y[i] = ROUND16(sum, SIG_SHIFT);
+ }
+}
+
+void celt_iir(const opus_val32 *x,
+ const opus_val16 *den,
+ opus_val32 *y,
+ int N,
+ int ord,
+ opus_val16 *mem)
+{
+ int i,j;
+ for (i=0;i<N;i++)
+ {
+ opus_val32 sum = x[i];
+ for (j=0;j<ord;j++)
+ {
+ sum -= MULT16_16(den[j],mem[j]);
+ }
+ for (j=ord-1;j>=1;j--)
+ {
+ mem[j]=mem[j-1];
+ }
+ mem[0] = ROUND16(sum,SIG_SHIFT);
+ y[i] = sum;
+ }
+}
+
+void _celt_autocorr(
+ const opus_val16 *x, /* in: [0...n-1] samples x */
+ opus_val32 *ac, /* out: [0...lag-1] ac values */
+ const opus_val16 *window,
+ int overlap,
+ int lag,
+ int n
+ )
+{
+ opus_val32 d;
+ int i;
+ VARDECL(opus_val16, xx);
+ SAVE_STACK;
+ ALLOC(xx, n, opus_val16);
+ celt_assert(n>0);
+ celt_assert(overlap>=0);
+ for (i=0;i<n;i++)
+ xx[i] = x[i];
+ for (i=0;i<overlap;i++)
+ {
+ xx[i] = MULT16_16_Q15(x[i],window[i]);
+ xx[n-i-1] = MULT16_16_Q15(x[n-i-1],window[i]);
+ }
+#ifdef FIXED_POINT
+ {
+ opus_val32 ac0=0;
+ int shift;
+ for(i=0;i<n;i++)
+ ac0 += SHR32(MULT16_16(xx[i],xx[i]),9);
+ ac0 += 1+n;
+
+ shift = celt_ilog2(ac0)-30+10;
+ shift = (shift+1)/2;
+ for(i=0;i<n;i++)
+ xx[i] = VSHR32(xx[i], shift);
+ }
+#endif
+ while (lag>=0)
+ {
+ for (i = lag, d = 0; i < n; i++)
+ d += xx[i] * xx[i-lag];
+ ac[lag] = d;
+ /*printf ("%f ", ac[lag]);*/
+ lag--;
+ }
+ /*printf ("\n");*/
+ ac[0] += 10;
+
+ RESTORE_STACK;
+}