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Index: apps/codecs/libatrac/atrac3data.h
===================================================================
--- apps/codecs/libatrac/atrac3data.h  (revision 24645)
+++ apps/codecs/libatrac/atrac3data.h  (working copy)
@@ -117,11 +117,11 @@


 /* tables for the scalefactor decoding */
-
+/* not needed anymore
 static const float iMaxQuant[8] = {
   0.0, 1.0/1.5, 1.0/2.5, 1.0/3.5, 1.0/4.5, 1.0/7.5, 1.0/15.5, 1.0/31.5
 };
-
+*/
 static const uint16_t subbandTab[33] = {
   0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160, 176, 192, 224,
   256, 288, 320, 352, 384, 416, 448, 480, 512, 576, 640, 704, 768, 896, 1024
Index: apps/codecs/libatrac/atrac3.c
===================================================================
--- apps/codecs/libatrac/atrac3.c  (revision 24645)
+++ apps/codecs/libatrac/atrac3.c  (working copy)
@@ -66,6 +66,7 @@
  * @param inlo      lower part of spectrum
  * @param inhi      higher part of spectrum
  * @param nIn       size of spectrum buffer
+ *
  */

 #if defined(CPU_ARM)
@@ -98,6 +99,20 @@
  * @param in        input buffer
  * @param win       windowing coefficients
  * @param nIn       size of spectrum buffer
+ * Reference implementation:
+ *
+ * for (j = nIn; j != 0; j--) {
+ *          s1 = fixmul32(in[0], win[0]);
+ *          s2 = fixmul32(in[1], win[1]);
+ *          for (i = 2; i < 48; i += 2) {
+ *              s1 += fixmul31(in[i  ], win[i  ]);
+ *              s2 += fixmul31(in[i+1], win[i+1]);
+ *          }
+ *          out[0] = s2;
+ *          out[1] = s1;
+ *          in += 2;
+ *          out += 2;
+ *      }
  */

 #if defined(CPU_ARM)
@@ -116,16 +131,62 @@
         int32_t i, j, s1, s2;

         for (j = nIn; j != 0; j--) {
-            /* i=0 */
-            s1 = fixmul31(win[0], in[0]);
-            s2 = fixmul31(win[1], in[1]);
-    
-            /* i=2..46 */
-            for (i = 2; i < 48; i += 2) {
-                s1 += fixmul31(win[i  ], in[i  ]);
-                s2 += fixmul31(win[i+1], in[i+1]);
-            }
-    
+            i = 0;
+            /*  0.. 7 */
+            s1  = fixmul31(win[i], in[i]); i++;
+            s2  = fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            /*  8..15 */
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            /* 16..23 */
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            /* 24..31 */
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            /* 32..39 */
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            /* 40..47 */
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]); i++;
+            s1 += fixmul31(win[i], in[i]); i++;
+            s2 += fixmul31(win[i], in[i]);
+
             out[0] = s2;
             out[1] = s1;

@@ -313,8 +374,8 @@
  * @param pOut          decoded band spectrum
  * @return outSubbands   subband counter, fix for broken specification/files
  */
-
-static int decodeSpectrum (GetBitContext *gb, int32_t *pOut)
+int decodeSpectrum (GetBitContext *gb, int32_t *pOut) ICODE_ATTR;
+int decodeSpectrum (GetBitContext *gb, int32_t *pOut)
 {
     int   numSubbands, codingMode, cnt, first, last, subbWidth, *pIn;
     int   subband_vlc_index[32], SF_idxs[32];