avcodec: Implementation of AAC_fixed_decoder (SBR-module)

Add fixed poind code.

Signed-off-by: Nedeljko Babic <nedeljko.babic@imgtec.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

1 files changed, 286 insertions, 0 deletions

diff --git a/libavcodec/sbrdsp_fixed.c b/libavcodec/sbrdsp_fixed.c
new file mode 100644
index 0000000000..5b7b7a6f9b
--- /dev/null
+++ b/libavcodec/sbrdsp_fixed.c
@@ -0,0 +1,286 @@
+/*
+ * AAC Spectral Band Replication decoding functions
+ * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
+ * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * Note: Rounding-to-nearest used unless otherwise stated
+ *
+ */
+
+#define USE_FIXED 1
+
+#include "aac.h"
+#include "config.h"
+#include "libavutil/attributes.h"
+#include "libavutil/intfloat.h"
+#include "sbrdsp.h"
+
+static SoftFloat sbr_sum_square_c(int (*x)[2], int n)
+{
+    SoftFloat ret;
+    int64_t accu = 0;
+    int i, nz, round;
+
+    for (i = 0; i < n; i += 2) {
+        accu += (int64_t)x[i + 0][0] * x[i + 0][0];
+        accu += (int64_t)x[i + 0][1] * x[i + 0][1];
+        accu += (int64_t)x[i + 1][0] * x[i + 1][0];
+        accu += (int64_t)x[i + 1][1] * x[i + 1][1];
+    }
+
+    i = (int)(accu >> 32);
+    if (i == 0) {
+        nz = 1;
+    } else {
+        nz = 0;
+        while (FFABS(i) < 0x40000000) {
+            i <<= 1;
+            nz++;
+        }
+        nz = 32 - nz;
+    }
+
+    round = 1 << (nz-1);
+    i = (int)((accu + round) >> nz);
+    i >>= 1;
+    ret = av_int2sf(i, 15 - nz);
+
+    return ret;
+}
+
+static void sbr_neg_odd_64_c(int *x)
+{
+    int i;
+    for (i = 1; i < 64; i += 2)
+        x[i] = -x[i];
+}
+
+static void sbr_qmf_pre_shuffle_c(int *z)
+{
+    int k;
+    z[64] = z[0];
+    z[65] = z[1];
+    for (k = 1; k < 32; k++) {
+        z[64+2*k  ] = -z[64 - k];
+        z[64+2*k+1] =  z[ k + 1];
+    }
+}
+
+static void sbr_qmf_post_shuffle_c(int W[32][2], const int *z)
+{
+    int k;
+    for (k = 0; k < 32; k++) {
+        W[k][0] = -z[63-k];
+        W[k][1] = z[k];
+    }
+}
+
+static void sbr_qmf_deint_neg_c(int *v, const int *src)
+{
+    int i;
+    for (i = 0; i < 32; i++) {
+        v[     i] = ( src[63 - 2*i    ] + 0x10) >> 5;
+        v[63 - i] = (-src[63 - 2*i - 1] + 0x10) >> 5;
+    }
+}
+
+static av_always_inline SoftFloat autocorr_calc(int64_t accu)
+{
+        int nz, mant, expo, round;
+        int i = (int)(accu >> 32);
+        if (i == 0) {
+            nz = 1;
+        } else {
+            nz = 0;
+            while (FFABS(i) < 0x40000000) {
+                i <<= 1;
+                nz++;
+            }
+            nz = 32-nz;
+        }
+
+        round = 1 << (nz-1);
+        mant = (int)((accu + round) >> nz);
+        mant = (mant + 0x40)>>7;
+        mant <<= 6;
+        expo = nz + 15;
+        return av_int2sf(mant, 30 - expo);
+}
+
+static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)
+{
+    int i;
+    int64_t real_sum, imag_sum;
+    int64_t accu_re = 0, accu_im = 0;
+
+    if (lag) {
+        for (i = 1; i < 38; i++) {
+            accu_re += (int64_t)x[i][0] * x[i+lag][0];
+            accu_re += (int64_t)x[i][1] * x[i+lag][1];
+            accu_im += (int64_t)x[i][0] * x[i+lag][1];
+            accu_im -= (int64_t)x[i][1] * x[i+lag][0];
+        }
+
+        real_sum = accu_re;
+        imag_sum = accu_im;
+
+        accu_re += (int64_t)x[ 0][0] * x[lag][0];
+        accu_re += (int64_t)x[ 0][1] * x[lag][1];
+        accu_im += (int64_t)x[ 0][0] * x[lag][1];
+        accu_im -= (int64_t)x[ 0][1] * x[lag][0];
+
+        phi[2-lag][1][0] = autocorr_calc(accu_re);
+        phi[2-lag][1][1] = autocorr_calc(accu_im);
+
+        if (lag == 1) {
+            accu_re = real_sum;
+            accu_im = imag_sum;
+            accu_re += (int64_t)x[38][0] * x[39][0];
+            accu_re += (int64_t)x[38][1] * x[39][1];
+            accu_im += (int64_t)x[38][0] * x[39][1];
+            accu_im -= (int64_t)x[38][1] * x[39][0];
+
+            phi[0][0][0] = autocorr_calc(accu_re);
+            phi[0][0][1] = autocorr_calc(accu_im);
+        }
+    } else {
+        for (i = 1; i < 38; i++) {
+            accu_re += (int64_t)x[i][0] * x[i][0];
+            accu_re += (int64_t)x[i][1] * x[i][1];
+        }
+        real_sum = accu_re;
+        accu_re += (int64_t)x[ 0][0] * x[ 0][0];
+        accu_re += (int64_t)x[ 0][1] * x[ 0][1];
+
+        phi[2][1][0] = autocorr_calc(accu_re);
+
+        accu_re = real_sum;
+        accu_re += (int64_t)x[38][0] * x[38][0];
+        accu_re += (int64_t)x[38][1] * x[38][1];
+
+        phi[1][0][0] = autocorr_calc(accu_re);
+    }
+}
+
+static void sbr_autocorrelate_c(const int x[40][2], SoftFloat phi[3][2][2])
+{
+    autocorrelate(x, phi, 0);
+    autocorrelate(x, phi, 1);
+    autocorrelate(x, phi, 2);
+}
+
+static void sbr_hf_gen_c(int (*X_high)[2], const int (*X_low)[2],
+                       const int alpha0[2], const int alpha1[2],
+                       int bw, int start, int end)
+{
+    int alpha[4];
+    int i;
+    int64_t accu;
+
+    accu = (int64_t)alpha0[0] * bw;
+    alpha[2] = (int)((accu + 0x40000000) >> 31);
+    accu = (int64_t)alpha0[1] * bw;
+    alpha[3] = (int)((accu + 0x40000000) >> 31);
+    accu = (int64_t)bw * bw;
+    bw = (int)((accu + 0x40000000) >> 31);
+    accu = (int64_t)alpha1[0] * bw;
+    alpha[0] = (int)((accu + 0x40000000) >> 31);
+    accu = (int64_t)alpha1[1] * bw;
+    alpha[1] = (int)((accu + 0x40000000) >> 31);
+
+    for (i = start; i < end; i++) {
+        accu  = (int64_t)X_low[i][0] * 0x20000000;
+        accu += (int64_t)X_low[i - 2][0] * alpha[0];
+        accu -= (int64_t)X_low[i - 2][1] * alpha[1];
+        accu += (int64_t)X_low[i - 1][0] * alpha[2];
+        accu -= (int64_t)X_low[i - 1][1] * alpha[3];
+        X_high[i][0] = (int)((accu + 0x10000000) >> 29);
+
+        accu  = (int64_t)X_low[i][1] * 0x20000000;
+        accu += (int64_t)X_low[i - 2][1] * alpha[0];
+        accu += (int64_t)X_low[i - 2][0] * alpha[1];
+        accu += (int64_t)X_low[i - 1][1] * alpha[2];
+        accu += (int64_t)X_low[i - 1][0] * alpha[3];
+        X_high[i][1] = (int)((accu + 0x10000000) >> 29);
+    }
+}
+
+static void sbr_hf_g_filt_c(int (*Y)[2], const int (*X_high)[40][2],
+                          const SoftFloat *g_filt, int m_max, intptr_t ixh)
+{
+    int m, r;
+    int64_t accu;
+
+    for (m = 0; m < m_max; m++) {
+        r = 1 << (22-g_filt[m].exp);
+        accu = (int64_t)X_high[m][ixh][0] * ((g_filt[m].mant + 0x40)>>7);
+        Y[m][0] = (int)((accu + r) >> (23-g_filt[m].exp));
+
+        accu = (int64_t)X_high[m][ixh][1] * ((g_filt[m].mant + 0x40)>>7);
+        Y[m][1] = (int)((accu + r) >> (23-g_filt[m].exp));
+    }
+}
+
+static av_always_inline void sbr_hf_apply_noise(int (*Y)[2],
+                                                const SoftFloat *s_m,
+                                                const SoftFloat *q_filt,
+                                                int noise,
+                                                int phi_sign0,
+                                                int phi_sign1,
+                                                int m_max)
+{
+    int m;
+
+    for (m = 0; m < m_max; m++) {
+        int y0 = Y[m][0];
+        int y1 = Y[m][1];
+        noise = (noise + 1) & 0x1ff;
+        if (s_m[m].mant) {
+            int shift, round;
+
+            shift = 22 - s_m[m].exp;
+            if (shift < 30) {
+                round = 1 << (shift-1);
+                y0 += (s_m[m].mant * phi_sign0 + round) >> shift;
+                y1 += (s_m[m].mant * phi_sign1 + round) >> shift;
+            }
+        } else {
+            int shift, round, tmp;
+            int64_t accu;
+
+            shift = 22 - q_filt[m].exp;
+            if (shift < 30) {
+                round = 1 << (shift-1);
+
+                accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][0];
+                tmp = (int)((accu + 0x40000000) >> 31);
+                y0 += (tmp + round) >> shift;
+
+                accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][1];
+                tmp = (int)((accu + 0x40000000) >> 31);
+                y1 += (tmp + round) >> shift;
+            }
+        }
+        Y[m][0] = y0;
+        Y[m][1] = y1;
+        phi_sign1 = -phi_sign1;
+    }
+}
+
+#include "sbrdsp_template.c"