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avconv: extend -vf syntax
[coroid/libav_saccubus.git] / libavcodec / celp_filters.c
index 6d23518..25a6744 100644 (file)
@@ -3,20 +3,20 @@
  *
  * Copyright (c) 2008 Vladimir Voroshilov
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "avcodec.h"
 #include "celp_filters.h"
 
-void ff_celp_convolve_circ(int16_t* fc_out,
-                           const int16_t* fc_in,
-                           const int16_t* filter,
-                           int len)
+void ff_celp_convolve_circ(int16_t* fc_out, const int16_t* fc_in,
+                           const int16_t* filter, int len)
 {
     int i, k;
 
@@ -47,22 +45,26 @@ void ff_celp_convolve_circ(int16_t* fc_out,
     }
 }
 
-int ff_celp_lp_synthesis_filter(int16_t *out,
-                                const int16_t* filter_coeffs,
-                                const int16_t* in,
-                                int buffer_length,
-                                int filter_length,
-                                int stop_on_overflow,
+void ff_celp_circ_addf(float *out, const float *in,
+                       const float *lagged, int lag, float fac, int n)
+{
+    int k;
+    for (k = 0; k < lag; k++)
+        out[k] = in[k] + fac * lagged[n + k - lag];
+    for (; k < n; k++)
+        out[k] = in[k] + fac * lagged[    k - lag];
+}
+
+int ff_celp_lp_synthesis_filter(int16_t *out, const int16_t *filter_coeffs,
+                                const int16_t *in, int buffer_length,
+                                int filter_length, int stop_on_overflow,
                                 int rounder)
 {
     int i,n;
 
-    // Avoids a +1 in the inner loop.
-    filter_length++;
-
     for (n = 0; n < buffer_length; n++) {
         int sum = rounder;
-        for (i = 1; i < filter_length; i++)
+        for (i = 1; i <= filter_length; i++)
             sum -= filter_coeffs[i-1] * out[n-i];
 
         sum = (sum >> 12) + in[n];
@@ -78,38 +80,130 @@ int ff_celp_lp_synthesis_filter(int16_t *out,
     return 0;
 }
 
-void ff_celp_lp_synthesis_filterf(float *out,
-                                  const float* filter_coeffs,
-                                  const float* in,
-                                  int buffer_length,
+void ff_celp_lp_synthesis_filterf(float *out, const float *filter_coeffs,
+                                  const float* in, int buffer_length,
                                   int filter_length)
 {
     int i,n;
 
-    // Avoids a +1 in the inner loop.
-    filter_length++;
-
+#if 0 // Unoptimized code path for improved readability
     for (n = 0; n < buffer_length; n++) {
         out[n] = in[n];
-        for (i = 1; i < filter_length; i++)
+        for (i = 1; i <= filter_length; i++)
             out[n] -= filter_coeffs[i-1] * out[n-i];
     }
+#else
+    float out0, out1, out2, out3;
+    float old_out0, old_out1, old_out2, old_out3;
+    float a,b,c;
+
+    a = filter_coeffs[0];
+    b = filter_coeffs[1];
+    c = filter_coeffs[2];
+    b -= filter_coeffs[0] * filter_coeffs[0];
+    c -= filter_coeffs[1] * filter_coeffs[0];
+    c -= filter_coeffs[0] * b;
+
+    old_out0 = out[-4];
+    old_out1 = out[-3];
+    old_out2 = out[-2];
+    old_out3 = out[-1];
+    for (n = 0; n <= buffer_length - 4; n+=4) {
+        float tmp0,tmp1,tmp2;
+        float val;
+
+        out0 = in[0];
+        out1 = in[1];
+        out2 = in[2];
+        out3 = in[3];
+
+        out0 -= filter_coeffs[2] * old_out1;
+        out1 -= filter_coeffs[2] * old_out2;
+        out2 -= filter_coeffs[2] * old_out3;
+
+        out0 -= filter_coeffs[1] * old_out2;
+        out1 -= filter_coeffs[1] * old_out3;
+
+        out0 -= filter_coeffs[0] * old_out3;
+
+        val = filter_coeffs[3];
+
+        out0 -= val * old_out0;
+        out1 -= val * old_out1;
+        out2 -= val * old_out2;
+        out3 -= val * old_out3;
+
+        old_out3 = out[-5];
+
+        for (i = 5; i <= filter_length; i += 2) {
+            val = filter_coeffs[i-1];
+
+            out0 -= val * old_out3;
+            out1 -= val * old_out0;
+            out2 -= val * old_out1;
+            out3 -= val * old_out2;
+
+            old_out2 = out[-i-1];
+
+            val = filter_coeffs[i];
+
+            out0 -= val * old_out2;
+            out1 -= val * old_out3;
+            out2 -= val * old_out0;
+            out3 -= val * old_out1;
+
+            FFSWAP(float, old_out0, old_out2);
+            old_out1 = old_out3;
+            old_out3 = out[-i-2];
+        }
+
+        tmp0 = out0;
+        tmp1 = out1;
+        tmp2 = out2;
+
+        out3 -= a * tmp2;
+        out2 -= a * tmp1;
+        out1 -= a * tmp0;
+
+        out3 -= b * tmp1;
+        out2 -= b * tmp0;
+
+        out3 -= c * tmp0;
+
+
+        out[0] = out0;
+        out[1] = out1;
+        out[2] = out2;
+        out[3] = out3;
+
+        old_out0 = out0;
+        old_out1 = out1;
+        old_out2 = out2;
+        old_out3 = out3;
+
+        out += 4;
+        in  += 4;
+    }
+
+    out -= n;
+    in -= n;
+    for (; n < buffer_length; n++) {
+        out[n] = in[n];
+        for (i = 1; i <= filter_length; i++)
+            out[n] -= filter_coeffs[i-1] * out[n-i];
+    }
+#endif
 }
 
-void ff_celp_lp_zero_synthesis_filterf(float *out,
-                                       const float* filter_coeffs,
-                                       const float* in,
-                                       int buffer_length,
+void ff_celp_lp_zero_synthesis_filterf(float *out, const float *filter_coeffs,
+                                       const float *in, int buffer_length,
                                        int filter_length)
 {
     int i,n;
 
-    // Avoids a +1 in the inner loop.
-    filter_length++;
-
     for (n = 0; n < buffer_length; n++) {
         out[n] = in[n];
-        for (i = 1; i < filter_length; i++)
-            out[n] -= filter_coeffs[i-1] * in[n-i];
+        for (i = 1; i <= filter_length; i++)
+            out[n] += filter_coeffs[i-1] * in[n-i];
     }
 }