| /*****************************************************************************/ |
| // Copyright 2006-2008 Adobe Systems Incorporated |
| // All Rights Reserved. |
| // |
| // NOTICE: Adobe permits you to use, modify, and distribute this file in |
| // accordance with the terms of the Adobe license agreement accompanying it. |
| /*****************************************************************************/ |
| |
| /* $Id: //mondo/dng_sdk_1_4/dng_sdk/source/dng_1d_table.h#1 $ */ |
| /* $DateTime: 2012/05/30 13:28:51 $ */ |
| /* $Change: 832332 $ */ |
| /* $Author: tknoll $ */ |
| |
| /** \file |
| * Definition of a lookup table based 1D floating-point to floating-point function abstraction using linear interpolation. |
| */ |
| |
| /*****************************************************************************/ |
| |
| #ifndef __dng_1d_table__ |
| #define __dng_1d_table__ |
| |
| /*****************************************************************************/ |
| |
| #include "dng_assertions.h" |
| #include "dng_auto_ptr.h" |
| #include "dng_classes.h" |
| #include "dng_types.h" |
| |
| /*****************************************************************************/ |
| |
| /// \brief A 1D floating-point lookup table using linear interpolation. |
| |
| class dng_1d_table |
| { |
| |
| public: |
| |
| /// Constants denoting size of table. |
| |
| enum |
| { |
| kTableBits = 12, //< Table is always a power of 2 in size. This is log2(kTableSize). |
| kTableSize = (1 << kTableBits) //< Number of entries in table. |
| }; |
| |
| protected: |
| |
| AutoPtr<dng_memory_block> fBuffer; |
| |
| real32 *fTable; |
| |
| public: |
| |
| dng_1d_table (); |
| |
| virtual ~dng_1d_table (); |
| |
| /// Set up table, initialize entries using functiion. |
| /// This method can throw an exception, e.g. if there is not enough memory. |
| /// \param allocator Memory allocator from which table memory is allocated. |
| /// \param function Table is initialized with values of finction.Evalluate(0.0) to function.Evaluate(1.0). |
| /// \param subSample If true, only sample the function a limited number of times and interpolate. |
| |
| void Initialize (dng_memory_allocator &allocator, |
| const dng_1d_function &function, |
| bool subSample = false); |
| |
| /// Lookup and interpolate mapping for an input. |
| /// \param x value from 0.0 to 1.0 used as input for mapping |
| /// \retval Approximation of function.Evaluate(x) |
| |
| real32 Interpolate (real32 x) const |
| { |
| |
| real32 y = x * (real32) kTableSize; |
| |
| int32 index = (int32) y; |
| |
| if (index < 0 || index > kTableSize) |
| { |
| |
| ThrowBadFormat("Index out of range."); |
| |
| } |
| |
| DNG_ASSERT (index >= 0 && index <= kTableSize, |
| "dng_1d_table::Interpolate parameter out of range"); |
| |
| real32 z = (real32) index; |
| |
| real32 fract = y - z; |
| |
| return fTable [index ] * (1.0f - fract) + |
| fTable [index + 1] * ( fract); |
| |
| } |
| |
| /// Direct access function for table data. |
| |
| const real32 * Table () const |
| { |
| return fTable; |
| } |
| |
| /// Expand the table to a 16-bit to 16-bit table. |
| |
| void Expand16 (uint16 *table16) const; |
| |
| private: |
| |
| void SubDivide (const dng_1d_function &function, |
| uint32 lower, |
| uint32 upper, |
| real32 maxDelta); |
| |
| // Hidden copy constructor and assignment operator. |
| |
| dng_1d_table (const dng_1d_table &table); |
| |
| dng_1d_table & operator= (const dng_1d_table &table); |
| |
| }; |
| |
| /*****************************************************************************/ |
| |
| #endif |
| |
| /*****************************************************************************/ |