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Section: Misc. Reference Manual Pages (3TIFF)
Updated: November 04, 2004
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NAME

TIFFGetBitRevTable, TIFFReverseBits, TIFFSwabShort, TIFFSwabLong, TIFFSwabArrayOfShort, TIFFSwabArrayOfLong - byte- and bit-swapping routines

SYNOPSIS

#include <tiffio.h>

const unsigned char* TIFFGetBitRevTable(int reversed)
void TIFFReverseBits(u_char *data, unsigned long nbytes)
void TIFFSwabShort(uint16 *data)
void TIFFSwabLong(uint32 *data)
void TIFFSwabArrayOfShort(uint16 *data, unsigned long nshorts)
void TIFFSwabArrayOfLong(uint32 *data, unsigned long nlongs)

DESCRIPTION

The following routines are used by the library to swap 16- and 32-bit data and to reverse the order of bits in bytes.

TIFFSwabShort and TIFFSwabLong swap the bytes in a single 16-bit and 32-bit item, respectively. TIFFSwabArrayOfShort and TIFFSwabArrayOfLong swap the bytes in an array of 16-bit and 32-bit items, respectively.

TIFFReverseBits replaces each byte in data with the equivalent bit-reversed value. This operation is performed with a lookup table, which is returned using the TIFFGetBitRevTable function. reversed parameter specifies which table should be returned. Supply 1 if you want bit reversal table. Supply 0 to get the table that do not reverse bit values. It is a lookup table that can be used as an identity function; i.e. TIFFNoBitRevTable[n] == n.

DIAGNOSTICS

None.

Index