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+/*************************** Fraunhofer IIS FDK Tools **********************
+
+ (C) Copyright Fraunhofer IIS (2007)
+ All Rights Reserved
+
+ Please be advised that this software and/or program delivery is
+ Confidential Information of Fraunhofer and subject to and covered by the
+
+ Fraunhofer IIS Software Evaluation Agreement
+ between Google Inc. and Fraunhofer
+ effective and in full force since March 1, 2012.
+
+ You may use this software and/or program only under the terms and
+ conditions described in the above mentioned Fraunhofer IIS Software
+ Evaluation Agreement. Any other and/or further use requires a separate agreement.
+
+
+ $Id$
+ Author(s):
+ Description:
+
+ This software and/or program is protected by copyright law and international
+ treaties. Any reproduction or distribution of this software and/or program,
+ or any portion of it, may result in severe civil and criminal penalties, and
+ will be prosecuted to the maximum extent possible under law.
+
+******************************************************************************/
+
+#if defined(__mips_dsp)
+
+#ifndef FUNCTION_getScalefactor_DBL
+#define FUNCTION_getScalefactor_DBL
+/*!
+ *
+ * \brief Calculate max possible scale factor for input vector
+ *
+ * \return Maximum scale factor
+ *
+ * This function can constitute a significant amount of computational complexity - very much depending on the
+ * bitrate. Since it is a rather small function, effective assembler optimization might be possible.
+ *
+ */
+inline INT getScalefactor(const FIXP_DBL *vector, /*!< Pointer to input vector */
+ INT len) /*!< Length of input vector */
+{
+ INT i;
+ FIXP_DBL maxVal = FL2FX_DBL(0.0f);
+
+ for(i=len;i!=0;i--){
+ maxVal |= __builtin_mips_absq_s_w(*vector++);
+ }
+
+ return fixMax((INT)0,(CntLeadingZeros(maxVal) - 1));
+}
+#endif
+
+#endif /*__mips_dsp */