1 files changed, 145 insertions, 0 deletions

diff --git a/lib/rbcodec/codecs/libwmavoice/acelp_filters.c b/lib/rbcodec/codecs/libwmavoice/acelp_filters.c
new file mode 100644
index 0000000000..c48c0e72ce
--- /dev/null
+++ b/lib/rbcodec/codecs/libwmavoice/acelp_filters.c
@@ -0,0 +1,145 @@
+/*
+ * various filters for ACELP-based codecs
+ *
+ * Copyright (c) 2008 Vladimir Voroshilov
+ *
+ * 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
+ */
+
+#include <inttypes.h>
+
+#include "avcodec.h"
+#include "acelp_filters.h"
+
+const int16_t ff_acelp_interp_filter[61] = { /* (0.15) */
+  29443, 28346, 25207, 20449, 14701,  8693,
+   3143, -1352, -4402, -5865, -5850, -4673,
+  -2783,  -672,  1211,  2536,  3130,  2991,
+   2259,  1170,     0, -1001, -1652, -1868,
+  -1666, -1147,  -464,   218,   756,  1060,
+   1099,   904,   550,   135,  -245,  -514,
+   -634,  -602,  -451,  -231,     0,   191,
+    308,   340,   296,   198,    78,   -36,
+   -120,  -163,  -165,  -132,   -79,   -19,
+     34,    73,    91,    89,    70,    38,
+      0,
+};
+
+void ff_acelp_interpolate(int16_t* out, const int16_t* in,
+                          const int16_t* filter_coeffs, int precision,
+                          int frac_pos, int filter_length, int length)
+{
+    int n, i;
+
+    //assert(frac_pos >= 0 && frac_pos < precision);
+
+    for (n = 0; n < length; n++) {
+        int idx = 0;
+        int v = 0x4000;
+
+        for (i = 0; i < filter_length;) {
+
+            /* The reference G.729 and AMR fixed point code performs clipping after
+               each of the two following accumulations.
+               Since clipping affects only the synthetic OVERFLOW test without
+               causing an int type overflow, it was moved outside the loop. */
+
+            /*  R(x):=ac_v[-k+x]
+                v += R(n-i)*ff_acelp_interp_filter(t+6i)
+                v += R(n+i+1)*ff_acelp_interp_filter(6-t+6i) */
+
+            v += in[n + i] * filter_coeffs[idx + frac_pos];
+            idx += precision;
+            i++;
+            v += in[n - i] * filter_coeffs[idx - frac_pos];
+        }
+        if (av_clip_int16(v >> 15) != (v >> 15))
+            av_log(NULL, AV_LOG_WARNING, "overflow that would need cliping in ff_acelp_interpolate()\n");
+        out[n] = v >> 15;
+    }
+}
+
+void ff_acelp_interpolatef(float *out, const float *in,
+                           const float *filter_coeffs, int precision,
+                           int frac_pos, int filter_length, int length)
+{
+    int n, i;
+
+    for (n = 0; n < length; n++) {
+        int idx = 0;
+        float v = 0;
+
+        for (i = 0; i < filter_length;) {
+            v += in[n + i] * filter_coeffs[idx + frac_pos];
+            idx += precision;
+            i++;
+            v += in[n - i] * filter_coeffs[idx - frac_pos];
+        }
+        out[n] = v;
+    }
+}
+
+
+void ff_acelp_high_pass_filter(int16_t* out, int hpf_f[2],
+                               const int16_t* in, int length)
+{
+    int i;
+    int tmp;
+
+    for (i = 0; i < length; i++) {
+        tmp  = (hpf_f[0]* 15836LL) >> 13;
+        tmp += (hpf_f[1]* -7667LL) >> 13;
+        tmp += 7699 * (in[i] - 2*in[i-1] + in[i-2]);
+
+        /* With "+0x800" rounding, clipping is needed
+           for ALGTHM and SPEECH tests. */
+        out[i] = av_clip_int16((tmp + 0x800) >> 12);
+
+        hpf_f[1] = hpf_f[0];
+        hpf_f[0] = tmp;
+    }
+}
+
+void ff_acelp_apply_order_2_transfer_function(float *out, const float *in,
+                                              const float zero_coeffs[2],
+                                              const float pole_coeffs[2],
+                                              float gain, float mem[2], int n)
+{
+    int i;
+    float tmp;
+
+    for (i = 0; i < n; i++) {
+        tmp = gain * in[i] - pole_coeffs[0] * mem[0] - pole_coeffs[1] * mem[1];
+        out[i] =       tmp + zero_coeffs[0] * mem[0] + zero_coeffs[1] * mem[1];
+
+        mem[1] = mem[0];
+        mem[0] = tmp;
+    }
+}
+
+void ff_tilt_compensation(float *mem, float tilt, float *samples, int size)
+{
+    float new_tilt_mem = samples[size - 1];
+    int i;
+
+    for (i = size - 1; i > 0; i--)
+        samples[i] -= tilt * samples[i - 1];
+
+    samples[0] -= tilt * *mem;
+    *mem = new_tilt_mem;
+}
+