convert.h

来自「这是符合Linux操作系统标准的POIXS 的pixops-2.0.5源程序」· C头文件 代码 · 共 164 行

/* Copyright (C) 2004 VMware, Inc.
 * This file is part of the Pixops Library.
 *
 * The pixops library is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Library General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or (at
 * your option) any later version.
 *
 * The pixops library is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
 * License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*
 * convert.h --
 *
 *      Pixel conversion macros.
 */

#ifndef _CONVERT_H_
#define _CONVERT_H_

#define REDMASK_BGR233		0x07
#define	GREENMASK_BGR233	0x38
#define	BLUEMASK_BGR233		0xc0

#define REDMASK_15		0x7c00
#define	GREENMASK_15		0x03e0
#define	BLUEMASK_15		0x001f

#define	GREEN_HIBIT_15		0x0200
#define GREEN_HILOSHIFT_15	4

#define REDMASK_16		0xf800
#define	GREENMASK_16		0x07e0
#define	BLUEMASK_16		0x001f

#define REDMASK_24		0x00ff0000
#define	GREENMASK_24		0x0000ff00
#define	BLUEMASK_24		0x000000ff

#define REDMASK_32		0x00ff0000
#define	GREENMASK_32		0x0000ff00
#define	BLUEMASK_32		0x000000ff

#define CONVERT_LONG_TO_SHORT(pix,                                      \
                              redMask, greenMask, blueMask,	        \
			      redShift, greenShift, blueShift)          \
   (((redMask) & ((pix) >> (redShift))) |				\
    ((greenMask) & ((pix) >> (greenShift))) |				\
    ((blueMask) & ((pix) >> (blueShift))))

#define CONVERT_SHORT_TO_LONG(pix,                                      \
                              redMask, greenMask, blueMask,	        \
			      redShift1, redShift2,			\
			      greenShift1, greenShift2,			\
			      blueShift1, blueShift2)			\
   ((REDMASK_32 &							\
     (((((pix) & (redMask)) >> (redShift1)) |				\
      (((pix) & (redMask)) >> (redShift2))) << 16)) |			\
    (GREENMASK_32 &							\
     (((((pix) & (greenMask)) >> (greenShift1)) |			\
      (((pix) & (greenMask)) >> (greenShift2))) << 8)) |		\
    (BLUEMASK_32 &							\
     ((((pix) & (blueMask)) << (blueShift1)) |				\
      (((pix) & (blueMask)) >> (blueShift2)))))

#define CONVERT_LONG_TO_8BGR(pix,                                       \
                             redMask, greenMask, blueMask,	        \
			     redShift, greenShift, blueShift)           \
   (((redMask) & ((pix) >> (redShift))) |				\
    ((greenMask) & ((pix) >> (greenShift))) |				\
    ((blueMask) & ((pix) << (blueShift))))

#define CONVERT_15_TO_8BGR(pix) \
   (CONVERT_LONG_TO_8BGR(pix, \
			 REDMASK_BGR233, GREENMASK_BGR233, BLUEMASK_BGR233, \
			 12, 4, 3))

#define CONVERT_15_TO_16(pix) \
   (((pix & (REDMASK_15 | GREENMASK_15)) << 1) | \
    ((pix & GREEN_HIBIT_15) >> GREEN_HILOSHIFT_15) | \
    (pix & BLUEMASK_16))

#define CONVERT_15_TO_24(pix) \
   (CONVERT_SHORT_TO_LONG(pix, REDMASK_15, GREENMASK_15, BLUEMASK_15, \
                          7, 12, 2, 7, 3, 2))

#define CONVERT_16_TO_8BGR(pix) \
   (CONVERT_LONG_TO_8BGR(pix, \
			 REDMASK_BGR233, GREENMASK_BGR233, BLUEMASK_BGR233, \
			 13, 5, 3))

#define CONVERT_16_TO_15(pix) \
   (((pix >> 1) & (REDMASK_15 | GREENMASK_15)) | (pix & BLUEMASK_15))

#define CONVERT_16_TO_24(pix) \
   (CONVERT_SHORT_TO_LONG(pix, REDMASK_16, GREENMASK_16, BLUEMASK_16, \
                          8, 13, 3, 9, 3, 2))

#define CONVERT_24_TO_8BGR(pix) \
   (CONVERT_LONG_TO_8BGR(pix, \
			 REDMASK_BGR233, GREENMASK_BGR233, BLUEMASK_BGR233, \
			 21, 10, 0))

#define CONVERT_24_TO_15(pix) \
   (CONVERT_LONG_TO_SHORT(pix, REDMASK_15, GREENMASK_15, BLUEMASK_15, 9, 6, 3))

#define CONVERT_24_TO_16(pix) \
   (CONVERT_LONG_TO_SHORT(pix, REDMASK_16, GREENMASK_16, BLUEMASK_16, 8, 5, 3))

#define CONVERT_NOP(pix) (pix)

#define BPPDEPTH(bpp, depth) ((depth == 24 && bpp == 32) ? 32 : depth)


inline static uint32
load_pixel (uint8 *src,
            int src_bytes_per_pixel,
            int src_depth,
            uint32 *src_colormap)
{
   switch (BPPDEPTH(src_bytes_per_pixel << 3, src_depth)) {
   case 8:
      return src_colormap[*src];
   case 15:
      return CONVERT_15_TO_24(*((uint16 *) (src)));
   case 16:
      return CONVERT_16_TO_24(*((uint16 *) (src)));
   default:
      return *((uint32 *) (src));
   }
}


inline static void
store_pixel (uint8 *dest,
             int dest_bytes_per_pixel,
             int dest_depth,
             uint32 pixel)
{
   switch (BPPDEPTH(dest_bytes_per_pixel << 3, dest_depth)) {
   case 8:
      *dest = CONVERT_24_TO_8BGR(pixel);
      break;
   case 15:
      *((uint16 *) dest) = CONVERT_24_TO_15(pixel);
      break;
   case 16:
      *((uint16 *) dest) = CONVERT_24_TO_16(pixel);
      break;
   default:
      *((uint32 *) dest) = pixel;
   }
}


#endif // _CONVERT_H_