63 lines
2.2 KiB
C
63 lines
2.2 KiB
C
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/*
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** Copyright 2003-2010, VisualOn, Inc.
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**
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** Licensed under the Apache License, Version 2.0 (the "License");
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** you may not use this file except in compliance with the License.
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** You may obtain a copy of the License at
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**
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** http://www.apache.org/licenses/LICENSE-2.0
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**
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** Unless required by applicable law or agreed to in writing, software
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** distributed under the License is distributed on an "AS IS" BASIS,
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** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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** See the License for the specific language governing permissions and
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** limitations under the License.
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*/
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/********************************************************************************
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*
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* File : log2.h
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* Purpose : Computes log2(L_x)
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*
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********************************************************************************
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*/
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#ifndef __LOG2_H__
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#define __LOG2_H__
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/*
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********************************************************************************
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* INCLUDE FILES
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********************************************************************************
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*/
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#include "typedef.h"
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/*
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********************************************************************************
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* DEFINITION OF DATA TYPES
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********************************************************************************
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*/
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/*
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********************************************************************************
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* DECLARATION OF PROTOTYPES
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********************************************************************************
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*/
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void Log2 (
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Word32 L_x, /* (i) : input value */
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Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */
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Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1)*/
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);
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void Log2_norm (
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Word32 L_x, /* (i) : input value (normalized) */
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Word16 exp, /* (i) : norm_l (L_x) */
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Word16 *exponent, /* (o) : Integer part of Log2. (range: 0<=val<=30) */
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Word16 *fraction /* (o) : Fractional part of Log2. (range: 0<=val<1) */
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);
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#endif //__LOG2_H__
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