Signed 16 bit normalized remap tables to go to/from normalized value to pixel value. More...

#include <ossimNormalizedS16RemapTable.h>

Inheritance diagram for ossimNormalizedS16RemapTable:

Public Types
enum	{ TABLE_ENTRIES = 65536, OFFSET_TO_ZERO = 32768, NULL_PIX = -32768, MIN_PIX = -32767 }

Public Member Functions
	ossimNormalizedS16RemapTable ()
	default constructor More...

virtual	~ossimNormalizedS16RemapTable ()
	virtual destructor More...

virtual ossim_int32	getEntries () const
	Gets the number of table entries. More...

virtual ossim_float64	operator[] (ossim_int32 pix) const
	Gets normalized value (between '0.0' and '1.0') from an int which should in scalar range of a signed 16 bit. More...

virtual ossim_float64	normFromPix (ossim_int32 pix) const
	Gets normalized value (between '0.0' and '1.0') from an int which should in scalar range of a signed 16 bit. More...

virtual ossim_int32	pixFromNorm (ossim_float64 normPix) const
	Gets pixel value from normalized value. More...

Public Member Functions inherited from ossimNormalizedRemapTable
	ossimNormalizedRemapTable ()
	default constructor More...

virtual	~ossimNormalizedRemapTable ()
	virtual destructor More...

virtual ossim_float64	getNormalizer () const
	Get the value used to normalize and un-normalize table entries. More...

Static Private Attributes
static ossim_float64	theTable [TABLE_ENTRIES]

static bool	theTableIsInitialized = false

Detailed Description

Signed 16 bit normalized remap tables to go to/from normalized value to pixel value.

Definition at line 27 of file ossimNormalizedS16RemapTable.h.

Member Enumeration Documentation

◆ anonymous enum

anonymous enum

Enumerator
TABLE_ENTRIES
OFFSET_TO_ZERO
NULL_PIX
MIN_PIX

Definition at line 37 of file ossimNormalizedS16RemapTable.h.

    {
       TABLE_ENTRIES  = 65536,  // 2^16 32767-(-32768)+1
       OFFSET_TO_ZERO = 32768,  // Gets -32768 to zero.
       NULL_PIX       = -32768,
       MIN_PIX        = -32767 
    };

Constructor & Destructor Documentation

◆ ossimNormalizedS16RemapTable()

ossimNormalizedS16RemapTable::ossimNormalizedS16RemapTable ( )

default constructor

Definition at line 19 of file ossimNormalizedS16RemapTable.cpp.

References getEntries(), ossimNormalizedRemapTable::getNormalizer(), theTable, and theTableIsInitialized.

    : ossimNormalizedRemapTable()
 {
    if (!theTableIsInitialized)
    {
       const ossim_int32   ENTRIES     = getEntries();
       const ossim_float64 DENOMINATOR = getNormalizer();
       
       //---
       // Initialize the remap table.
       //
       // Specialized for elevation, make -32768 and -32767 map to 0 since
       // DTED NULL is -32767.
       //
       // NOTE: Zero will always remap back to -32768 with this hack.  This
       // could cause issues on writers that use pixFromNorm(). (drb)
       //---
       theTable[0] = 0.0; // Index zero always for null.
       theTable[1] = 0.0; // Specialized for DTED.
 
       for (ossim_int32 i = 2; i < ENTRIES; ++i)
       {
          theTable[i] = static_cast<ossim_float64>(i)/DENOMINATOR;
       }
 
       theTableIsInitialized = true;
    }
 }

◆ ~ossimNormalizedS16RemapTable()

ossimNormalizedS16RemapTable::~ossimNormalizedS16RemapTable ( )

virtual

virtual destructor

Definition at line 48 of file ossimNormalizedS16RemapTable.cpp.

49 {}

Member Function Documentation

◆ getEntries()

ossim_int32 ossimNormalizedS16RemapTable::getEntries ( ) const

inlinevirtual

Gets the number of table entries.

Returns: The number of entries in a table.

Implements ossimNormalizedRemapTable.

Definition at line 89 of file ossimNormalizedS16RemapTable.h.

References TABLE_ENTRIES.

Referenced by ossimNormalizedS16RemapTable().

 {
    return TABLE_ENTRIES;
 }

◆ normFromPix()

ossim_float64 ossimNormalizedS16RemapTable::normFromPix ( ossim_int32 pix ) const

inlinevirtual

Gets normalized value (between '0.0' and '1.0') from an int which should in scalar range of a signed 16 bit.

Note: This table is specialized to map both -32768 and -32767 to 0 since dted data has a null of -32767.

Returns: Value between 0.0 and 1.0.

Implements ossimNormalizedRemapTable.

Definition at line 107 of file ossimNormalizedS16RemapTable.h.

References OFFSET_TO_ZERO, and theTable.

Referenced by ossimS16ImageData::convertToNormalizedDouble(), ossimS16ImageData::copyTileToNormalizedBuffer(), and ossimS16ImageData::getNormalizedFloat().

 {
    ossim_float64 result = 0;
 
    // Move pix into table range.  This will take -32768 to 0.
    ossim_int32 p = pix + OFFSET_TO_ZERO;
 
    result = (p < TABLE_ENTRIES ? ( p >= 0 ? theTable[p] : 0.0) : 1.0);
 
    return result;
 }

◆ operator[]()

ossim_float64 ossimNormalizedS16RemapTable::operator[] ( ossim_int32 pix ) const

inlinevirtual

Gets normalized value (between '0.0' and '1.0') from an int which should in scalar range of a signed 16 bit.

Note: This table is specialized to map both -32768 and -32767 to 0 since dted data has a null of -32767.

Returns: Value between 0.0 and 1.0.

Implements ossimNormalizedRemapTable.

Definition at line 94 of file ossimNormalizedS16RemapTable.h.

References OFFSET_TO_ZERO, and theTable.

 {
    ossim_float64 result = 0;
 
    // Move pix into table range.  This will take -32768 to 0.
    ossim_int32 p = pix + OFFSET_TO_ZERO;
 
    result = (p < TABLE_ENTRIES ? ( p >= 0 ? theTable[p] : 0.0) : 1.0);
 
    return result;
 }

◆ pixFromNorm()

ossim_int32 ossimNormalizedS16RemapTable::pixFromNorm ( ossim_float64 normPix ) const

inlinevirtual

Gets pixel value from normalized value.

Valid returns range is signed 16 bit range or -32768 to 32767.

Returns: Value between -32768 to 32767.

Implements ossimNormalizedRemapTable.

Definition at line 120 of file ossimNormalizedS16RemapTable.h.

References ossimNormalizedRemapTable::getNormalizer(), MIN_PIX, NULL_PIX, and OFFSET_TO_ZERO.

Referenced by ossimS16ImageData::copyNormalizedBufferToTile(), and ossimS16ImageData::setNormalizedFloat().

 {
    if(normPix <= 0.0) return NULL_PIX;
    
    // Clamp between 0 and 1 on the way in.
    ossim_float64 p = (normPix<1.0) ? ( (normPix>0.0) ? normPix : 0.0) : 1.0;
 
    // Un-normalize.
    p = p * getNormalizer(); // TABLE_ENTRIES - 1;
 
    //---
    // Move pixel into sign range then round it.  This will take  65535 to
    // 32767 which is the max pixel for this scalar type.
    //---
    p = ossim::round<ossim_int32>(p - OFFSET_TO_ZERO);
 
    if (p == NULL_PIX)
    {
       // norm pixel came in just above zero so should be at least min.
       p = MIN_PIX; 
    }
 
    return static_cast<ossim_int32>(p);
 }