Source/Utilities.h - platform/external/free-image - Git at Google

 // ==========================================================
 // Utility functions
 //
 // Design and implementation by
 // - Floris van den Berg (flvdberg@wxs.nl)
 // - Hervé Drolon <drolon@infonie.fr>
 // - Ryan Rubley (ryan@lostreality.org)
 //
 // This file is part of FreeImage 3
 //
 // COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
 // OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
 // THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
 // OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
 // CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
 // THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
 // SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
 // PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
 // THIS DISCLAIMER.
 //
 // Use at your own risk!
 // ==========================================================

 #ifndef UTILITIES_H
 #define UTILITIES_H

 // ==========================================================
 //   Standard includes used by the library
 // ==========================================================

 #include <math.h>
 #include <stdlib.h>
 #include <memory.h>
 #include <stdio.h>
 #include <string.h>
 #include <stdarg.h>
 #include <ctype.h>
 #include <assert.h>
 #include <limits.h>

 #include <string>
 #include <list>
 #include <map>
 #include <set>
 #include <vector>
 #include <stack>
 #include <sstream>
 #include <algorithm>

 // ==========================================================
 //   Bitmap palette and pixels alignment
 // ==========================================================

 #define FIBITMAP_ALIGNMENT	16	// We will use a 16 bytes alignment boundary

 // Memory allocation on a specified alignment boundary
 // defined in BitmapAccess.cpp

 void* FreeImage_Aligned_Malloc(size_t amount, size_t alignment);
 void FreeImage_Aligned_Free(void* mem);

 // ==========================================================
 //   File I/O structs
 // ==========================================================

 // these structs are for file I/O and should not be confused with similar
 // structs in FreeImage.h which are for in-memory bitmap handling

 #ifdef _WIN32
 #pragma pack(push, 1)
 #else
 #pragma pack(1)
 #endif // _WIN32

 typedef struct tagFILE_RGBA {
   unsigned char r,g,b,a;
 } FILE_RGBA;

 typedef struct tagFILE_BGRA {
   unsigned char b,g,r,a;
 } FILE_BGRA;

 typedef struct tagFILE_RGB {
   unsigned char r,g,b;
 } FILE_RGB;

 typedef struct tagFILE_BGR {
   unsigned char b,g,r;
 } FILE_BGR;

 #ifdef _WIN32
 #pragma pack(pop)
 #else
 #pragma pack()
 #endif // _WIN32

 // ==========================================================
 //   Utility functions
 // ==========================================================

 #ifndef _WIN32
 inline char*
 i2a(unsigned i, char *a, unsigned r) {
 	if (i/r > 0) a = i2a(i/r,a,r);
 	*a = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"[i%r];
 	return a+1;
 }

 /**
  Transforms integer i into an ascii string and stores the result in a;
  string is encoded in the base indicated by r.
  @param i Number to be converted
  @param a String result
  @param r Base of value; must be in the range 2 - 36
  @return Returns a
 */
 inline char *
 _itoa(int i, char *a, int r) {
 	r = ((r < 2) || (r > 36)) ? 10 : r;
 	if(i < 0) {
 		*a = '-';
 		*i2a(-i, a+1, r) = 0;
 	}
 	else *i2a(i, a, r) = 0;
 	return a;
 }

 #endif // !_WIN32

 inline unsigned char
 HINIBBLE (unsigned char byte) {
 	return byte & 0xF0;
 }

 inline unsigned char
 LOWNIBBLE (unsigned char byte) {
 	return byte & 0x0F;
 }

 inline int
 CalculateUsedBits(int bits) {
 	int bit_count = 0;
 	unsigned bit = 1;

 	for (unsigned i = 0; i < 32; i++) {
 		if ((bits & bit) == bit) {
 			bit_count++;
 		}

 		bit <<= 1;
 	}

 	return bit_count;
 }

 inline int
 CalculateLine(int width, int bitdepth) {
 	return ((width * bitdepth) + 7) / 8;
 }

 inline int
 CalculatePitch(int line) {
 	return line + 3 & ~3;
 }

 inline int
 CalculateUsedPaletteEntries(int bit_count) {
 	if ((bit_count >= 1) && (bit_count <= 8))
 		return 1 << bit_count;

 	return 0;
 }

 inline unsigned char *
 CalculateScanLine(unsigned char *bits, unsigned pitch, int scanline) {
 	return (bits + (pitch * scanline));
 }

 inline void
 ReplaceExtension(char *result, const char *filename, const char *extension) {
 	for (size_t i = strlen(filename) - 1; i > 0; --i) {
 		if (filename[i] == '.') {
 			memcpy(result, filename, i);
 			result[i] = '.';
 			memcpy(result + i + 1, extension, strlen(extension) + 1);
 			return;
 		}
 	}

 	memcpy(result, filename, strlen(filename));
 	result[strlen(filename)] = '.';
 	memcpy(result + strlen(filename) + 1, extension, strlen(extension) + 1);
 }

 // ==========================================================
 //   Big Endian / Little Endian utility functions
 // ==========================================================

 inline WORD
 __SwapUInt16(WORD arg) {
 #if defined(_MSC_VER) && _MSC_VER >= 1310
 	return _byteswap_ushort(arg);
 #elif defined(__i386__) && defined(__GNUC__)
 	__asm__("xchgb %b0, %h0" : "+q" (arg));
 	return arg;
 #elif defined(__ppc__) && defined(__GNUC__)
 	WORD result;
 	__asm__("lhbrx %0,0,%1" : "=r" (result) : "r" (&arg), "m" (arg));
 	return result;
 #else
 	// swap bytes
 	WORD result;
 	result = ((arg << 8) & 0xFF00) | ((arg >> 8) & 0x00FF);
 	return result;
 #endif
 }

 inline DWORD
 __SwapUInt32(DWORD arg) {
 #if defined(_MSC_VER) && _MSC_VER >= 1310
 	return _byteswap_ulong(arg);
 #elif defined(__i386__) && defined(__GNUC__)
 	__asm__("bswap %0" : "+r" (arg));
 	return arg;
 #elif defined(__ppc__) && defined(__GNUC__)
 	DWORD result;
 	__asm__("lwbrx %0,0,%1" : "=r" (result) : "r" (&arg), "m" (arg));
 	return result;
 #else
 	// swap words then bytes
 	DWORD result;
 	result = ((arg & 0x000000FF) << 24) | ((arg & 0x0000FF00) << 8) | ((arg >> 8) & 0x0000FF00) | ((arg >> 24) & 0x000000FF);
 	return result;
 #endif
 }

 /**
 for later use ...
 inline uint64_t
 SwapInt64(uint64_t arg) {
 #if defined(_MSC_VER) && _MSC_VER >= 1310
 	return _byteswap_uint64(arg);
 #else
 	union Swap {
 		uint64_t sv;
 		uint32_t ul[2];
 	} tmp, result;
 	tmp.sv = arg;
 	result.ul[0] = SwapInt32(tmp.ul[1]);
 	result.ul[1] = SwapInt32(tmp.ul[0]);
 	return result.sv;
 #endif
 }
 */

 inline void
 SwapShort(WORD *sp) {
 	*sp = __SwapUInt16(*sp);
 }

 inline void
 SwapLong(DWORD *lp) {
 	*lp = __SwapUInt32(*lp);
 }

 // ==========================================================
 //   Greyscale and color conversion
 // ==========================================================

 #define GREY(r, g, b) (BYTE)(((WORD)r * 77 + (WORD)g * 150 + (WORD)b * 29) >> 8)	// .299R + .587G + .114B
 /*
 #define GREY(r, g, b) (BYTE)(((WORD)r * 169 + (WORD)g * 256 + (WORD)b * 87) >> 9)	// .33R + 0.5G + .17B
 */

 #define RGB565(b, g, r) ((((b) >> 3) << FI16_565_BLUE_SHIFT) | (((g) >> 2) << FI16_565_GREEN_SHIFT) | (((r) >> 3) << FI16_565_RED_SHIFT))
 #define RGB555(b, g, r) ((((b) >> 3) << FI16_555_BLUE_SHIFT) | (((g) >> 3) << FI16_555_GREEN_SHIFT) | (((r) >> 3) << FI16_555_RED_SHIFT))

 #define FORMAT_RGB565(dib) ((FreeImage_GetRedMask(dib) == FI16_565_RED_MASK) &&(FreeImage_GetGreenMask(dib) == FI16_565_GREEN_MASK) &&(FreeImage_GetBlueMask(dib) == FI16_565_BLUE_MASK))
 #define RGBQUAD_TO_WORD(dib, color) (FORMAT_RGB565(dib) ? RGB565((color)->rgbBlue, (color)->rgbGreen, (color)->rgbRed) : RGB555((color)->rgbBlue, (color)->rgbGreen, (color)->rgbRed))

 #define CREATE_GREYSCALE_PALETTE(palette, entries) \
 	for (unsigned i = 0, v = 0; i < entries; i++, v += 0x00FFFFFF / (entries - 1)) { \
 		((unsigned *)palette)[i] = v; \
 	}

 #define CREATE_GREYSCALE_PALETTE_REVERSE(palette, entries) \
 	for (unsigned i = 0, v = 0x00FFFFFF; i < entries; i++, v -= (0x00FFFFFF / (entries - 1))) { \
 		((unsigned *)palette)[i] = v; \
 	}

 // ==========================================================
 //   Template utility functions
 // ==========================================================

 /// Max function
 template <class T> T MAX(T a, T b) {
 	return (a > b) ? a: b;
 }

 /// Min function
 template <class T> T MIN(T a, T b) {
 	return (a < b) ? a: b;
 }

 /// INPLACESWAP adopted from codeguru.com
 template <class T> void INPLACESWAP(T& a, T& b) {
 	a ^= b; b ^= a; a ^= b;
 }

 /** This procedure computes minimum min and maximum max
  of n numbers using only (3n/2) - 2 comparisons.
  min = L[i1] and max = L[i2].
  ref: Aho A.V., Hopcroft J.E., Ullman J.D.,
  The design and analysis of computer algorithms,
  Addison-Wesley, Reading, 1974.
 */
 template <class T> void
 MAXMIN(const T* L, long n, T& max, T& min) {
 	long i1, i2, i, j;
 	T x1, x2;
 	long k1, k2;

 	i1 = 0; i2 = 0; min = L[0]; max = L[0]; j = 0;
 	if((n % 2) != 0)  j = 1;
 	for(i = j; i < n; i+= 2) {
 		k1 = i; k2 = i+1;
 		x1 = L[k1]; x2 = L[k2];
 		if(x1 > x2)	{
 			k1 = k2;  k2 = i;
 			x1 = x2;  x2 = L[k2];
 		}
 		if(x1 < min) {
 			min = x1;  i1 = k1;
 		}
 		if(x2 > max) {
 			max = x2;  i2 = k2;
 		}
 	}
 }

 // ==========================================================
 //   Generic error messages
 // ==========================================================

 static const char *FI_MSG_ERROR_MEMORY = "Memory allocation failed";
 static const char *FI_MSG_ERROR_DIB_MEMORY = "DIB allocation failed";
 static const char *FI_MSG_ERROR_PARSING = "Parsing error";
 static const char *FI_MSG_ERROR_MAGIC_NUMBER = "Invalid magic number";
 static const char *FI_MSG_ERROR_UNSUPPORTED_FORMAT = "Unsupported format";
 static const char *FI_MSG_ERROR_UNSUPPORTED_COMPRESSION = "Unsupported compression type";


 #endif // UTILITIES_H
	// ==========================================================
	// Utility functions
	//
	// Design and implementation by
	// - Floris van den Berg (flvdberg@wxs.nl)
	// - Hervé Drolon <drolon@infonie.fr>
	// - Ryan Rubley (ryan@lostreality.org)
	//
	// This file is part of FreeImage 3
	//
	// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
	// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
	// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
	// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
	// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
	// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
	// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
	// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
	// THIS DISCLAIMER.
	//
	// Use at your own risk!
	// ==========================================================

	#ifndef UTILITIES_H
	#define UTILITIES_H

	// ==========================================================
	// Standard includes used by the library
	// ==========================================================

	#include <math.h>
	#include <stdlib.h>
	#include <memory.h>
	#include <stdio.h>
	#include <string.h>
	#include <stdarg.h>
	#include <ctype.h>
	#include <assert.h>
	#include <limits.h>

	#include <string>
	#include <list>
	#include <map>
	#include <set>
	#include <vector>
	#include <stack>
	#include <sstream>
	#include <algorithm>

	// ==========================================================
	// Bitmap palette and pixels alignment
	// ==========================================================

	#define FIBITMAP_ALIGNMENT 16 // We will use a 16 bytes alignment boundary

	// Memory allocation on a specified alignment boundary
	// defined in BitmapAccess.cpp

	void* FreeImage_Aligned_Malloc(size_t amount, size_t alignment);
	void FreeImage_Aligned_Free(void* mem);

	// ==========================================================
	// File I/O structs
	// ==========================================================

	// these structs are for file I/O and should not be confused with similar
	// structs in FreeImage.h which are for in-memory bitmap handling

	#ifdef _WIN32
	#pragma pack(push, 1)
	#else
	#pragma pack(1)
	#endif // _WIN32

	typedef struct tagFILE_RGBA {
	unsigned char r,g,b,a;
	} FILE_RGBA;

	typedef struct tagFILE_BGRA {
	unsigned char b,g,r,a;
	} FILE_BGRA;

	typedef struct tagFILE_RGB {
	unsigned char r,g,b;
	} FILE_RGB;

	typedef struct tagFILE_BGR {
	unsigned char b,g,r;
	} FILE_BGR;

	#ifdef _WIN32
	#pragma pack(pop)
	#else
	#pragma pack()
	#endif // _WIN32

	// ==========================================================
	// Utility functions
	// ==========================================================

	#ifndef _WIN32
	inline char*
	i2a(unsigned i, char *a, unsigned r) {
	if (i/r > 0) a = i2a(i/r,a,r);
	*a = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"[i%r];
	return a+1;
	}

	/**
	Transforms integer i into an ascii string and stores the result in a;
	string is encoded in the base indicated by r.
	@param i Number to be converted
	@param a String result
	@param r Base of value; must be in the range 2 - 36
	@return Returns a
	*/
	inline char *
	_itoa(int i, char *a, int r) {
	r = ((r < 2) \|\| (r > 36)) ? 10 : r;
	if(i < 0) {
	*a = '-';
	*i2a(-i, a+1, r) = 0;
	}
	else *i2a(i, a, r) = 0;
	return a;
	}

	#endif // !_WIN32

	inline unsigned char
	HINIBBLE (unsigned char byte) {
	return byte & 0xF0;
	}

	inline unsigned char
	LOWNIBBLE (unsigned char byte) {
	return byte & 0x0F;
	}

	inline int
	CalculateUsedBits(int bits) {
	int bit_count = 0;
	unsigned bit = 1;

	for (unsigned i = 0; i < 32; i++) {
	if ((bits & bit) == bit) {
	bit_count++;
	}

	bit <<= 1;
	}

	return bit_count;
	}

	inline int
	CalculateLine(int width, int bitdepth) {
	return ((width * bitdepth) + 7) / 8;
	}

	inline int
	CalculatePitch(int line) {
	return line + 3 & ~3;
	}

	inline int
	CalculateUsedPaletteEntries(int bit_count) {
	if ((bit_count >= 1) && (bit_count <= 8))
	return 1 << bit_count;

	return 0;
	}

	inline unsigned char *
	CalculateScanLine(unsigned char *bits, unsigned pitch, int scanline) {
	return (bits + (pitch * scanline));
	}

	inline void
	ReplaceExtension(char result, const char filename, const char *extension) {
	for (size_t i = strlen(filename) - 1; i > 0; --i) {
	if (filename[i] == '.') {
	memcpy(result, filename, i);
	result[i] = '.';
	memcpy(result + i + 1, extension, strlen(extension) + 1);
	return;
	}
	}

	memcpy(result, filename, strlen(filename));
	result[strlen(filename)] = '.';
	memcpy(result + strlen(filename) + 1, extension, strlen(extension) + 1);
	}

	// ==========================================================
	// Big Endian / Little Endian utility functions
	// ==========================================================

	inline WORD
	__SwapUInt16(WORD arg) {
	#if defined(_MSC_VER) && _MSC_VER >= 1310
	return _byteswap_ushort(arg);
	#elif defined(__i386__) && defined(__GNUC__)
	__asm__("xchgb %b0, %h0" : "+q" (arg));
	return arg;
	#elif defined(__ppc__) && defined(__GNUC__)
	WORD result;
	__asm__("lhbrx %0,0,%1" : "=r" (result) : "r" (&arg), "m" (arg));
	return result;
	#else
	// swap bytes
	WORD result;
	result = ((arg << 8) & 0xFF00) \| ((arg >> 8) & 0x00FF);
	return result;
	#endif
	}

	inline DWORD
	__SwapUInt32(DWORD arg) {
	#if defined(_MSC_VER) && _MSC_VER >= 1310
	return _byteswap_ulong(arg);
	#elif defined(__i386__) && defined(__GNUC__)
	__asm__("bswap %0" : "+r" (arg));
	return arg;
	#elif defined(__ppc__) && defined(__GNUC__)
	DWORD result;
	__asm__("lwbrx %0,0,%1" : "=r" (result) : "r" (&arg), "m" (arg));
	return result;
	#else
	// swap words then bytes
	DWORD result;
	result = ((arg & 0x000000FF) << 24) \| ((arg & 0x0000FF00) << 8) \| ((arg >> 8) & 0x0000FF00) \| ((arg >> 24) & 0x000000FF);
	return result;
	#endif
	}

	/**
	for later use ...
	inline uint64_t
	SwapInt64(uint64_t arg) {
	#if defined(_MSC_VER) && _MSC_VER >= 1310
	return _byteswap_uint64(arg);
	#else
	union Swap {
	uint64_t sv;
	uint32_t ul[2];
	} tmp, result;
	tmp.sv = arg;
	result.ul[0] = SwapInt32(tmp.ul[1]);
	result.ul[1] = SwapInt32(tmp.ul[0]);
	return result.sv;
	#endif
	}
	*/

	inline void
	SwapShort(WORD *sp) {
	sp = __SwapUInt16(sp);
	}

	inline void
	SwapLong(DWORD *lp) {
	lp = __SwapUInt32(lp);
	}

	// ==========================================================
	// Greyscale and color conversion
	// ==========================================================

	#define GREY(r, g, b) (BYTE)(((WORD)r * 77 + (WORD)g * 150 + (WORD)b * 29) >> 8) // .299R + .587G + .114B
	/*
	#define GREY(r, g, b) (BYTE)(((WORD)r * 169 + (WORD)g * 256 + (WORD)b * 87) >> 9) // .33R + 0.5G + .17B
	*/

	#define RGB565(b, g, r) ((((b) >> 3) << FI16_565_BLUE_SHIFT) \| (((g) >> 2) << FI16_565_GREEN_SHIFT) \| (((r) >> 3) << FI16_565_RED_SHIFT))
	#define RGB555(b, g, r) ((((b) >> 3) << FI16_555_BLUE_SHIFT) \| (((g) >> 3) << FI16_555_GREEN_SHIFT) \| (((r) >> 3) << FI16_555_RED_SHIFT))

	#define FORMAT_RGB565(dib) ((FreeImage_GetRedMask(dib) == FI16_565_RED_MASK) &&(FreeImage_GetGreenMask(dib) == FI16_565_GREEN_MASK) &&(FreeImage_GetBlueMask(dib) == FI16_565_BLUE_MASK))
	#define RGBQUAD_TO_WORD(dib, color) (FORMAT_RGB565(dib) ? RGB565((color)->rgbBlue, (color)->rgbGreen, (color)->rgbRed) : RGB555((color)->rgbBlue, (color)->rgbGreen, (color)->rgbRed))

	#define CREATE_GREYSCALE_PALETTE(palette, entries) \
	for (unsigned i = 0, v = 0; i < entries; i++, v += 0x00FFFFFF / (entries - 1)) { \
	((unsigned *)palette)[i] = v; \
	}

	#define CREATE_GREYSCALE_PALETTE_REVERSE(palette, entries) \
	for (unsigned i = 0, v = 0x00FFFFFF; i < entries; i++, v -= (0x00FFFFFF / (entries - 1))) { \
	((unsigned *)palette)[i] = v; \
	}

	// ==========================================================
	// Template utility functions
	// ==========================================================

	/// Max function
	template <class T> T MAX(T a, T b) {
	return (a > b) ? a: b;
	}

	/// Min function
	template <class T> T MIN(T a, T b) {
	return (a < b) ? a: b;
	}

	/// INPLACESWAP adopted from codeguru.com
	template <class T> void INPLACESWAP(T& a, T& b) {
	a ^= b; b ^= a; a ^= b;
	}

	/** This procedure computes minimum min and maximum max
	of n numbers using only (3n/2) - 2 comparisons.
	min = L[i1] and max = L[i2].
	ref: Aho A.V., Hopcroft J.E., Ullman J.D.,
	The design and analysis of computer algorithms,
	Addison-Wesley, Reading, 1974.
	*/
	template <class T> void
	MAXMIN(const T* L, long n, T& max, T& min) {
	long i1, i2, i, j;
	T x1, x2;
	long k1, k2;

	i1 = 0; i2 = 0; min = L[0]; max = L[0]; j = 0;
	if((n % 2) != 0) j = 1;
	for(i = j; i < n; i+= 2) {
	k1 = i; k2 = i+1;
	x1 = L[k1]; x2 = L[k2];
	if(x1 > x2) {
	k1 = k2; k2 = i;
	x1 = x2; x2 = L[k2];
	}
	if(x1 < min) {
	min = x1; i1 = k1;
	}
	if(x2 > max) {
	max = x2; i2 = k2;
	}
	}
	}

	// ==========================================================
	// Generic error messages
	// ==========================================================

	static const char *FI_MSG_ERROR_MEMORY = "Memory allocation failed";
	static const char *FI_MSG_ERROR_DIB_MEMORY = "DIB allocation failed";
	static const char *FI_MSG_ERROR_PARSING = "Parsing error";
	static const char *FI_MSG_ERROR_MAGIC_NUMBER = "Invalid magic number";
	static const char *FI_MSG_ERROR_UNSUPPORTED_FORMAT = "Unsupported format";
	static const char *FI_MSG_ERROR_UNSUPPORTED_COMPRESSION = "Unsupported compression type";


	#endif // UTILITIES_H