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-rw-r--r--media/libstagefright/codecs/amrwbenc/src/az_isp.c536
1 files changed, 268 insertions, 268 deletions
diff --git a/media/libstagefright/codecs/amrwbenc/src/az_isp.c b/media/libstagefright/codecs/amrwbenc/src/az_isp.c
index 8259f91..9333d19 100644
--- a/media/libstagefright/codecs/amrwbenc/src/az_isp.c
+++ b/media/libstagefright/codecs/amrwbenc/src/az_isp.c
@@ -1,268 +1,268 @@
-/*
- ** Copyright 2003-2010, VisualOn, Inc.
- **
- ** Licensed under the Apache License, Version 2.0 (the "License");
- ** you may not use this file except in compliance with the License.
- ** You may obtain a copy of the License at
- **
- ** http://www.apache.org/licenses/LICENSE-2.0
- **
- ** Unless required by applicable law or agreed to in writing, software
- ** distributed under the License is distributed on an "AS IS" BASIS,
- ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- ** See the License for the specific language governing permissions and
- ** limitations under the License.
- */
-
-/***********************************************************************
-* File: az_isp.c
-*
-* Description:
-*-----------------------------------------------------------------------*
-* Compute the ISPs from the LPC coefficients (order=M) *
-*-----------------------------------------------------------------------*
-* *
-* The ISPs are the roots of the two polynomials F1(z) and F2(z) *
-* defined as *
-* F1(z) = A(z) + z^-m A(z^-1) *
-* and F2(z) = A(z) - z^-m A(z^-1) *
-* *
-* For a even order m=2n, F1(z) has M/2 conjugate roots on the unit *
-* circle and F2(z) has M/2-1 conjugate roots on the unit circle in *
-* addition to two roots at 0 and pi. *
-* *
-* For a 16th order LP analysis, F1(z) and F2(z) can be written as *
-* *
-* F1(z) = (1 + a[M]) PRODUCT (1 - 2 cos(w_i) z^-1 + z^-2 ) *
-* i=0,2,4,6,8,10,12,14 *
-* *
-* F2(z) = (1 - a[M]) (1 - z^-2) PRODUCT (1 - 2 cos(w_i) z^-1 + z^-2 ) *
-* i=1,3,5,7,9,11,13 *
-* *
-* The ISPs are the M-1 frequencies w_i, i=0...M-2 plus the last *
-* predictor coefficient a[M]. *
-*-----------------------------------------------------------------------*
-
-************************************************************************/
-
-#include "typedef.h"
-#include "basic_op.h"
-#include "oper_32b.h"
-#include "stdio.h"
-#include "grid100.tab"
-
-#define M 16
-#define NC (M/2)
-
-/* local function */
-static __inline Word16 Chebps2(Word16 x, Word16 f[], Word32 n);
-
-void Az_isp(
- Word16 a[], /* (i) Q12 : predictor coefficients */
- Word16 isp[], /* (o) Q15 : Immittance spectral pairs */
- Word16 old_isp[] /* (i) : old isp[] (in case not found M roots) */
- )
-{
- Word32 i, j, nf, ip, order;
- Word16 xlow, ylow, xhigh, yhigh, xmid, ymid, xint;
- Word16 x, y, sign, exp;
- Word16 *coef;
- Word16 f1[NC + 1], f2[NC];
- Word32 t0;
- /*-------------------------------------------------------------*
- * find the sum and diff polynomials F1(z) and F2(z) *
- * F1(z) = [A(z) + z^M A(z^-1)] *
- * F2(z) = [A(z) - z^M A(z^-1)]/(1-z^-2) *
- * *
- * for (i=0; i<NC; i++) *
- * { *
- * f1[i] = a[i] + a[M-i]; *
- * f2[i] = a[i] - a[M-i]; *
- * } *
- * f1[NC] = 2.0*a[NC]; *
- * *
- * for (i=2; i<NC; i++) Divide by (1-z^-2) *
- * f2[i] += f2[i-2]; *
- *-------------------------------------------------------------*/
- for (i = 0; i < NC; i++)
- {
- t0 = a[i] << 15;
- f1[i] = vo_round(t0 + (a[M - i] << 15)); /* =(a[i]+a[M-i])/2 */
- f2[i] = vo_round(t0 - (a[M - i] << 15)); /* =(a[i]-a[M-i])/2 */
- }
- f1[NC] = a[NC];
- for (i = 2; i < NC; i++) /* Divide by (1-z^-2) */
- f2[i] = add1(f2[i], f2[i - 2]);
-
- /*---------------------------------------------------------------------*
- * Find the ISPs (roots of F1(z) and F2(z) ) using the *
- * Chebyshev polynomial evaluation. *
- * The roots of F1(z) and F2(z) are alternatively searched. *
- * We start by finding the first root of F1(z) then we switch *
- * to F2(z) then back to F1(z) and so on until all roots are found. *
- * *
- * - Evaluate Chebyshev pol. at grid points and check for sign change.*
- * - If sign change track the root by subdividing the interval *
- * 2 times and ckecking sign change. *
- *---------------------------------------------------------------------*/
- nf = 0; /* number of found frequencies */
- ip = 0; /* indicator for f1 or f2 */
- coef = f1;
- order = NC;
- xlow = vogrid[0];
- ylow = Chebps2(xlow, coef, order);
- j = 0;
- while ((nf < M - 1) && (j < GRID_POINTS))
- {
- j ++;
- xhigh = xlow;
- yhigh = ylow;
- xlow = vogrid[j];
- ylow = Chebps2(xlow, coef, order);
- if ((ylow * yhigh) <= (Word32) 0)
- {
- /* divide 2 times the interval */
- for (i = 0; i < 2; i++)
- {
- xmid = (xlow >> 1) + (xhigh >> 1); /* xmid = (xlow + xhigh)/2 */
- ymid = Chebps2(xmid, coef, order);
- if ((ylow * ymid) <= (Word32) 0)
- {
- yhigh = ymid;
- xhigh = xmid;
- } else
- {
- ylow = ymid;
- xlow = xmid;
- }
- }
- /*-------------------------------------------------------------*
- * Linear interpolation *
- * xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); *
- *-------------------------------------------------------------*/
- x = xhigh - xlow;
- y = yhigh - ylow;
- if (y == 0)
- {
- xint = xlow;
- } else
- {
- sign = y;
- y = abs_s(y);
- exp = norm_s(y);
- y = y << exp;
- y = div_s((Word16) 16383, y);
- t0 = x * y;
- t0 = (t0 >> (19 - exp));
- y = vo_extract_l(t0); /* y= (xhigh-xlow)/(yhigh-ylow) in Q11 */
- if (sign < 0)
- y = -y;
- t0 = ylow * y; /* result in Q26 */
- t0 = (t0 >> 10); /* result in Q15 */
- xint = vo_sub(xlow, vo_extract_l(t0)); /* xint = xlow - ylow*y */
- }
- isp[nf] = xint;
- xlow = xint;
- nf++;
- if (ip == 0)
- {
- ip = 1;
- coef = f2;
- order = NC - 1;
- } else
- {
- ip = 0;
- coef = f1;
- order = NC;
- }
- ylow = Chebps2(xlow, coef, order);
- }
- }
- /* Check if M-1 roots found */
- if(nf < M - 1)
- {
- for (i = 0; i < M; i++)
- {
- isp[i] = old_isp[i];
- }
- } else
- {
- isp[M - 1] = a[M] << 3; /* From Q12 to Q15 with saturation */
- }
- return;
-}
-
-/*--------------------------------------------------------------*
-* function Chebps2: *
-* ~~~~~~~ *
-* Evaluates the Chebishev polynomial series *
-*--------------------------------------------------------------*
-* *
-* The polynomial order is *
-* n = M/2 (M is the prediction order) *
-* The polynomial is given by *
-* C(x) = f(0)T_n(x) + f(1)T_n-1(x) + ... +f(n-1)T_1(x) + f(n)/2 *
-* Arguments: *
-* x: input value of evaluation; x = cos(frequency) in Q15 *
-* f[]: coefficients of the pol. in Q11 *
-* n: order of the pol. *
-* *
-* The value of C(x) is returned. (Satured to +-1.99 in Q14) *
-* *
-*--------------------------------------------------------------*/
-
-static __inline Word16 Chebps2(Word16 x, Word16 f[], Word32 n)
-{
- Word32 i, cheb;
- Word16 b0_h, b0_l, b1_h, b1_l, b2_h, b2_l;
- Word32 t0;
-
- /* Note: All computation are done in Q24. */
-
- t0 = f[0] << 13;
- b2_h = t0 >> 16;
- b2_l = (t0 & 0xffff)>>1;
-
- t0 = ((b2_h * x)<<1) + (((b2_l * x)>>15)<<1);
- t0 <<= 1;
- t0 += (f[1] << 13); /* + f[1] in Q24 */
-
- b1_h = t0 >> 16;
- b1_l = (t0 & 0xffff) >> 1;
-
- for (i = 2; i < n; i++)
- {
- t0 = ((b1_h * x)<<1) + (((b1_l * x)>>15)<<1);
-
- t0 += (b2_h * (-16384))<<1;
- t0 += (f[i] << 12);
- t0 <<= 1;
- t0 -= (b2_l << 1); /* t0 = 2.0*x*b1 - b2 + f[i]; */
-
- b0_h = t0 >> 16;
- b0_l = (t0 & 0xffff) >> 1;
-
- b2_l = b1_l; /* b2 = b1; */
- b2_h = b1_h;
- b1_l = b0_l; /* b1 = b0; */
- b1_h = b0_h;
- }
-
- t0 = ((b1_h * x)<<1) + (((b1_l * x)>>15)<<1);
- t0 += (b2_h * (-32768))<<1; /* t0 = x*b1 - b2 */
- t0 -= (b2_l << 1);
- t0 += (f[n] << 12); /* t0 = x*b1 - b2 + f[i]/2 */
-
- t0 = L_shl2(t0, 6); /* Q24 to Q30 with saturation */
-
- cheb = extract_h(t0); /* Result in Q14 */
-
- if (cheb == -32768)
- {
- cheb = -32767; /* to avoid saturation in Az_isp */
- }
- return (cheb);
-}
-
-
-
+/*
+ ** Copyright 2003-2010, VisualOn, Inc.
+ **
+ ** Licensed under the Apache License, Version 2.0 (the "License");
+ ** you may not use this file except in compliance with the License.
+ ** You may obtain a copy of the License at
+ **
+ ** http://www.apache.org/licenses/LICENSE-2.0
+ **
+ ** Unless required by applicable law or agreed to in writing, software
+ ** distributed under the License is distributed on an "AS IS" BASIS,
+ ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ ** See the License for the specific language governing permissions and
+ ** limitations under the License.
+ */
+
+/***********************************************************************
+* File: az_isp.c
+*
+* Description:
+*-----------------------------------------------------------------------*
+* Compute the ISPs from the LPC coefficients (order=M) *
+*-----------------------------------------------------------------------*
+* *
+* The ISPs are the roots of the two polynomials F1(z) and F2(z) *
+* defined as *
+* F1(z) = A(z) + z^-m A(z^-1) *
+* and F2(z) = A(z) - z^-m A(z^-1) *
+* *
+* For a even order m=2n, F1(z) has M/2 conjugate roots on the unit *
+* circle and F2(z) has M/2-1 conjugate roots on the unit circle in *
+* addition to two roots at 0 and pi. *
+* *
+* For a 16th order LP analysis, F1(z) and F2(z) can be written as *
+* *
+* F1(z) = (1 + a[M]) PRODUCT (1 - 2 cos(w_i) z^-1 + z^-2 ) *
+* i=0,2,4,6,8,10,12,14 *
+* *
+* F2(z) = (1 - a[M]) (1 - z^-2) PRODUCT (1 - 2 cos(w_i) z^-1 + z^-2 ) *
+* i=1,3,5,7,9,11,13 *
+* *
+* The ISPs are the M-1 frequencies w_i, i=0...M-2 plus the last *
+* predictor coefficient a[M]. *
+*-----------------------------------------------------------------------*
+
+************************************************************************/
+
+#include "typedef.h"
+#include "basic_op.h"
+#include "oper_32b.h"
+#include "stdio.h"
+#include "grid100.tab"
+
+#define M 16
+#define NC (M/2)
+
+/* local function */
+static __inline Word16 Chebps2(Word16 x, Word16 f[], Word32 n);
+
+void Az_isp(
+ Word16 a[], /* (i) Q12 : predictor coefficients */
+ Word16 isp[], /* (o) Q15 : Immittance spectral pairs */
+ Word16 old_isp[] /* (i) : old isp[] (in case not found M roots) */
+ )
+{
+ Word32 i, j, nf, ip, order;
+ Word16 xlow, ylow, xhigh, yhigh, xmid, ymid, xint;
+ Word16 x, y, sign, exp;
+ Word16 *coef;
+ Word16 f1[NC + 1], f2[NC];
+ Word32 t0;
+ /*-------------------------------------------------------------*
+ * find the sum and diff polynomials F1(z) and F2(z) *
+ * F1(z) = [A(z) + z^M A(z^-1)] *
+ * F2(z) = [A(z) - z^M A(z^-1)]/(1-z^-2) *
+ * *
+ * for (i=0; i<NC; i++) *
+ * { *
+ * f1[i] = a[i] + a[M-i]; *
+ * f2[i] = a[i] - a[M-i]; *
+ * } *
+ * f1[NC] = 2.0*a[NC]; *
+ * *
+ * for (i=2; i<NC; i++) Divide by (1-z^-2) *
+ * f2[i] += f2[i-2]; *
+ *-------------------------------------------------------------*/
+ for (i = 0; i < NC; i++)
+ {
+ t0 = a[i] << 15;
+ f1[i] = vo_round(t0 + (a[M - i] << 15)); /* =(a[i]+a[M-i])/2 */
+ f2[i] = vo_round(t0 - (a[M - i] << 15)); /* =(a[i]-a[M-i])/2 */
+ }
+ f1[NC] = a[NC];
+ for (i = 2; i < NC; i++) /* Divide by (1-z^-2) */
+ f2[i] = add1(f2[i], f2[i - 2]);
+
+ /*---------------------------------------------------------------------*
+ * Find the ISPs (roots of F1(z) and F2(z) ) using the *
+ * Chebyshev polynomial evaluation. *
+ * The roots of F1(z) and F2(z) are alternatively searched. *
+ * We start by finding the first root of F1(z) then we switch *
+ * to F2(z) then back to F1(z) and so on until all roots are found. *
+ * *
+ * - Evaluate Chebyshev pol. at grid points and check for sign change.*
+ * - If sign change track the root by subdividing the interval *
+ * 2 times and ckecking sign change. *
+ *---------------------------------------------------------------------*/
+ nf = 0; /* number of found frequencies */
+ ip = 0; /* indicator for f1 or f2 */
+ coef = f1;
+ order = NC;
+ xlow = vogrid[0];
+ ylow = Chebps2(xlow, coef, order);
+ j = 0;
+ while ((nf < M - 1) && (j < GRID_POINTS))
+ {
+ j ++;
+ xhigh = xlow;
+ yhigh = ylow;
+ xlow = vogrid[j];
+ ylow = Chebps2(xlow, coef, order);
+ if ((ylow * yhigh) <= (Word32) 0)
+ {
+ /* divide 2 times the interval */
+ for (i = 0; i < 2; i++)
+ {
+ xmid = (xlow >> 1) + (xhigh >> 1); /* xmid = (xlow + xhigh)/2 */
+ ymid = Chebps2(xmid, coef, order);
+ if ((ylow * ymid) <= (Word32) 0)
+ {
+ yhigh = ymid;
+ xhigh = xmid;
+ } else
+ {
+ ylow = ymid;
+ xlow = xmid;
+ }
+ }
+ /*-------------------------------------------------------------*
+ * Linear interpolation *
+ * xint = xlow - ylow*(xhigh-xlow)/(yhigh-ylow); *
+ *-------------------------------------------------------------*/
+ x = xhigh - xlow;
+ y = yhigh - ylow;
+ if (y == 0)
+ {
+ xint = xlow;
+ } else
+ {
+ sign = y;
+ y = abs_s(y);
+ exp = norm_s(y);
+ y = y << exp;
+ y = div_s((Word16) 16383, y);
+ t0 = x * y;
+ t0 = (t0 >> (19 - exp));
+ y = vo_extract_l(t0); /* y= (xhigh-xlow)/(yhigh-ylow) in Q11 */
+ if (sign < 0)
+ y = -y;
+ t0 = ylow * y; /* result in Q26 */
+ t0 = (t0 >> 10); /* result in Q15 */
+ xint = vo_sub(xlow, vo_extract_l(t0)); /* xint = xlow - ylow*y */
+ }
+ isp[nf] = xint;
+ xlow = xint;
+ nf++;
+ if (ip == 0)
+ {
+ ip = 1;
+ coef = f2;
+ order = NC - 1;
+ } else
+ {
+ ip = 0;
+ coef = f1;
+ order = NC;
+ }
+ ylow = Chebps2(xlow, coef, order);
+ }
+ }
+ /* Check if M-1 roots found */
+ if(nf < M - 1)
+ {
+ for (i = 0; i < M; i++)
+ {
+ isp[i] = old_isp[i];
+ }
+ } else
+ {
+ isp[M - 1] = a[M] << 3; /* From Q12 to Q15 with saturation */
+ }
+ return;
+}
+
+/*--------------------------------------------------------------*
+* function Chebps2: *
+* ~~~~~~~ *
+* Evaluates the Chebishev polynomial series *
+*--------------------------------------------------------------*
+* *
+* The polynomial order is *
+* n = M/2 (M is the prediction order) *
+* The polynomial is given by *
+* C(x) = f(0)T_n(x) + f(1)T_n-1(x) + ... +f(n-1)T_1(x) + f(n)/2 *
+* Arguments: *
+* x: input value of evaluation; x = cos(frequency) in Q15 *
+* f[]: coefficients of the pol. in Q11 *
+* n: order of the pol. *
+* *
+* The value of C(x) is returned. (Satured to +-1.99 in Q14) *
+* *
+*--------------------------------------------------------------*/
+
+static __inline Word16 Chebps2(Word16 x, Word16 f[], Word32 n)
+{
+ Word32 i, cheb;
+ Word16 b0_h, b0_l, b1_h, b1_l, b2_h, b2_l;
+ Word32 t0;
+
+ /* Note: All computation are done in Q24. */
+
+ t0 = f[0] << 13;
+ b2_h = t0 >> 16;
+ b2_l = (t0 & 0xffff)>>1;
+
+ t0 = ((b2_h * x)<<1) + (((b2_l * x)>>15)<<1);
+ t0 <<= 1;
+ t0 += (f[1] << 13); /* + f[1] in Q24 */
+
+ b1_h = t0 >> 16;
+ b1_l = (t0 & 0xffff) >> 1;
+
+ for (i = 2; i < n; i++)
+ {
+ t0 = ((b1_h * x)<<1) + (((b1_l * x)>>15)<<1);
+
+ t0 += (b2_h * (-16384))<<1;
+ t0 += (f[i] << 12);
+ t0 <<= 1;
+ t0 -= (b2_l << 1); /* t0 = 2.0*x*b1 - b2 + f[i]; */
+
+ b0_h = t0 >> 16;
+ b0_l = (t0 & 0xffff) >> 1;
+
+ b2_l = b1_l; /* b2 = b1; */
+ b2_h = b1_h;
+ b1_l = b0_l; /* b1 = b0; */
+ b1_h = b0_h;
+ }
+
+ t0 = ((b1_h * x)<<1) + (((b1_l * x)>>15)<<1);
+ t0 += (b2_h * (-32768))<<1; /* t0 = x*b1 - b2 */
+ t0 -= (b2_l << 1);
+ t0 += (f[n] << 12); /* t0 = x*b1 - b2 + f[i]/2 */
+
+ t0 = L_shl2(t0, 6); /* Q24 to Q30 with saturation */
+
+ cheb = extract_h(t0); /* Result in Q14 */
+
+ if (cheb == -32768)
+ {
+ cheb = -32767; /* to avoid saturation in Az_isp */
+ }
+ return (cheb);
+}
+
+
+
generated by cgit v1.1 at 2024-05-29 12:35:00 +0000