text: /*
  
  SDL2_imageFilter.h: byte-image "filter" routines 
  
  Copyright (C) 2012-2014  Andreas Schiffler
  
  This software is provided 'as-is', without any express or implied
  warranty. In no event will the authors be held liable for any damages
  arising from the use of this software.
  
  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:
  
  1. The origin of this software must not be misrepresented; you must not
  claim that you wrote the original software. If you use this software
  in a product, an acknowledgment in the product documentation would be
  appreciated but is not required.
  
  2. Altered source versions must be plainly marked as such, and must not be
  misrepresented as being the original software.
  
  3. This notice may not be removed or altered from any source
  distribution.
  
  Andreas Schiffler -- aschiffler at ferzkopp dot net
  
  */
  
  #ifndef _SDL2_imageFilter_h
  #define _SDL2_imageFilter_h
  
  /* Set up for C function definitions, even when using C++ */
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  	/* ---- Function Prototypes */
  
  #ifdef _WIN32
  #  if defined(DLL_EXPORT) && !defined(LIBSDL2_GFX_DLL_IMPORT)
  #    define SDL2_IMAGEFILTER_SCOPE __declspec(dllexport)
  #  else
  #    ifdef LIBSDL2_GFX_DLL_IMPORT
  #      define SDL2_IMAGEFILTER_SCOPE __declspec(dllimport)
  #    endif
  #  endif
  #elif defined(__OS2__)
  #  if defined(DLL_EXPORT) && !defined(LIBSDL2_GFX_DLL_IMPORT)
  #    define SDL2_IMAGEFILTER_SCOPE __declspec(dllexport)
  #  else
  #    define SDL2_IMAGEFILTER_SCOPE   extern
  #  endif
  #elif defined(SDL2GFX_SYM_VISIBILITY)
  #    define SDL2_IMAGEFILTER_SCOPE __attribute__((visibility("default")))
  #endif
  #ifndef SDL2_IMAGEFILTER_SCOPE
  #  define SDL2_IMAGEFILTER_SCOPE extern
  #endif
  
  	/* Comments:                                                                           */
  	/*  1.) MMX functions work best if all data blocks are aligned on a 32 bytes boundary. */
  	/*  2.) Data that is not within an 8 byte boundary is processed using the C routine.   */
  	/*  3.) Convolution routines do not have C routines at this time.                      */
  
  	// Detect MMX capability in CPU
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMMXdetect(void);
  
  	// Force use of MMX off (or turn possible use back on)
  	SDL2_IMAGEFILTER_SCOPE void SDL_imageFilterMMXoff(void);
  	SDL2_IMAGEFILTER_SCOPE void SDL_imageFilterMMXon(void);
  
  	//
  	// All routines return:
  	//   0   OK
  	//  -1   Error (internal error, parameter error)
  	//
  
  	//  SDL_imageFilterAdd: D = saturation255(S1 + S2)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterAdd(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterMean: D = S1/2 + S2/2
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMean(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterSub: D = saturation0(S1 - S2)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterSub(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterAbsDiff: D = | S1 - S2 |
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterAbsDiff(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterMult: D = saturation(S1 * S2)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMult(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterMultNor: D = S1 * S2   (non-MMX)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMultNor(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterMultDivby2: D = saturation255(S1/2 * S2)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMultDivby2(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest,
  		unsigned int length);
  
  	//  SDL_imageFilterMultDivby4: D = saturation255(S1/2 * S2/2)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMultDivby4(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest,
  		unsigned int length);
  
  	//  SDL_imageFilterBitAnd: D = S1 & S2
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterBitAnd(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterBitOr: D = S1 | S2
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterBitOr(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterDiv: D = S1 / S2   (non-MMX)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterDiv(unsigned char *Src1, unsigned char *Src2, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterBitNegation: D = !S
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterBitNegation(unsigned char *Src1, unsigned char *Dest, unsigned int length);
  
  	//  SDL_imageFilterAddByte: D = saturation255(S + C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterAddByte(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char C);
  
  	//  SDL_imageFilterAddUint: D = saturation255(S + (uint)C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterAddUint(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned int C);
  
  	//  SDL_imageFilterAddByteToHalf: D = saturation255(S/2 + C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterAddByteToHalf(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char C);
  
  	//  SDL_imageFilterSubByte: D = saturation0(S - C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterSubByte(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char C);
  
  	//  SDL_imageFilterSubUint: D = saturation0(S - (uint)C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterSubUint(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned int C);
  
  	//  SDL_imageFilterShiftRight: D = saturation0(S >> N)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftRight(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char N);
  
  	//  SDL_imageFilterShiftRightUint: D = saturation0((uint)S >> N)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftRightUint(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char N);
  
  	//  SDL_imageFilterMultByByte: D = saturation255(S * C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterMultByByte(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char C);
  
  	//  SDL_imageFilterShiftRightAndMultByByte: D = saturation255((S >> N) * C)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftRightAndMultByByte(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char N, unsigned char C);
  
  	//  SDL_imageFilterShiftLeftByte: D = (S << N)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftLeftByte(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char N);
  
  	//  SDL_imageFilterShiftLeftUint: D = ((uint)S << N)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftLeftUint(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char N);
  
  	//  SDL_imageFilterShiftLeft: D = saturation255(S << N)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterShiftLeft(unsigned char *Src1, unsigned char *Dest, unsigned int length, unsigned char N);
  
  	//  SDL_imageFilterBinarizeUsingThreshold: D = S >= T ? 255:0
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterBinarizeUsingThreshold(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char T);
  
  	//  SDL_imageFilterClipToRange: D = (S >= Tmin) & (S <= Tmax) 255:0
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterClipToRange(unsigned char *Src1, unsigned char *Dest, unsigned int length,
  		unsigned char Tmin, unsigned char Tmax);
  
  	//  SDL_imageFilterNormalizeLinear: D = saturation255((Nmax - Nmin)/(Cmax - Cmin)*(S - Cmin) + Nmin)
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterNormalizeLinear(unsigned char *Src, unsigned char *Dest, unsigned int length, int Cmin,
  		int Cmax, int Nmin, int Nmax);
  
  #if 0  /* These are not exported in SDL2_gfx .. */
  	/* !!! NO C-ROUTINE FOR THESE FUNCTIONS YET !!! */
  
  	//  SDL_imageFilterConvolveKernel3x3Divide: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel3x3Divide(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel, unsigned char Divisor);
  
  	//  SDL_imageFilterConvolveKernel5x5Divide: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel5x5Divide(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel, unsigned char Divisor);
  
  	//  SDL_imageFilterConvolveKernel7x7Divide: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel7x7Divide(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel, unsigned char Divisor);
  
  	//  SDL_imageFilterConvolveKernel9x9Divide: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel9x9Divide(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel, unsigned char Divisor);
  
  	//  SDL_imageFilterConvolveKernel3x3ShiftRight: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel3x3ShiftRight(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel,
  		unsigned char NRightShift);
  
  	//  SDL_imageFilterConvolveKernel5x5ShiftRight: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel5x5ShiftRight(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel,
  		unsigned char NRightShift);
  
  	//  SDL_imageFilterConvolveKernel7x7ShiftRight: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel7x7ShiftRight(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel,
  		unsigned char NRightShift);
  
  	//  SDL_imageFilterConvolveKernel9x9ShiftRight: Dij = saturation0and255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterConvolveKernel9x9ShiftRight(unsigned char *Src, unsigned char *Dest, int rows,
  		int columns, signed short *Kernel,
  		unsigned char NRightShift);
  
  	//  SDL_imageFilterSobelX: Dij = saturation255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterSobelX(unsigned char *Src, unsigned char *Dest, int rows, int columns);
  
  	//  SDL_imageFilterSobelXShiftRight: Dij = saturation255( ... )
  	SDL2_IMAGEFILTER_SCOPE int SDL_imageFilterSobelXShiftRight(unsigned char *Src, unsigned char *Dest, int rows, int columns,
  		unsigned char NRightShift);
  #endif /* #if 0 */
  
  	/* Ends C function definitions when using C++ */
  #ifdef __cplusplus
  }
  #endif
  
  #endif				/* _SDL_imageFilter_h */
  