/src/FreeImage/Source/FreeImage/ConversionUINT16.cpp

  1// ==========================================================
  2// Bitmap conversion routines
  3//
  4// Design and implementation by
  5// - Hervé Drolon (drolon@infonie.fr)
  6//
  7// This file is part of FreeImage 3
  8//
  9// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY
 10// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES
 11// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE
 12// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED
 13// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT
 14// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY
 15// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL
 16// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER
 17// THIS DISCLAIMER.
 18//
 19// Use at your own risk!
 20// ==========================================================
 21
 22#include "FreeImage.h"
 23#include "Utilities.h"
 24
 25// ----------------------------------------------------------
 26//   smart convert X to UINT16
 27// ----------------------------------------------------------
 28
 29FIBITMAP * DLL_CALLCONV
 30FreeImage_ConvertToUINT16(FIBITMAP *dib) {
 31	FIBITMAP *src = NULL;
 32	FIBITMAP *dst = NULL;
 33
 34	if(!FreeImage_HasPixels(dib)) return NULL;
 35
 36	const FREE_IMAGE_TYPE src_type = FreeImage_GetImageType(dib);
 37
 38	// check for allowed conversions 
 39	switch(src_type) {
 40		case FIT_BITMAP:
 41		{
 42			// convert to greyscale if needed
 43			if((FreeImage_GetBPP(dib) == 8) && (FreeImage_GetColorType(dib) == FIC_MINISBLACK)) {
 44				src = dib;
 45			} else {
 46				src = FreeImage_ConvertToGreyscale(dib);
 47				if(!src) return NULL;
 48			}
 49			break;
 50		}
 51		case FIT_UINT16:
 52			// UINT16 type : clone the src
 53			return FreeImage_Clone(dib);
 54			break;
 55		case FIT_RGB16:
 56			// allow conversion from 48-bit RGB
 57			src = dib;
 58			break;
 59		case FIT_RGBA16:
 60			// allow conversion from 64-bit RGBA (ignore the alpha channel)
 61			src = dib;
 62			break;
 63		default:
 64			return NULL;
 65	}
 66
 67	// allocate dst image
 68
 69	const unsigned width = FreeImage_GetWidth(src);
 70	const unsigned height = FreeImage_GetHeight(src);
 71
 72	dst = FreeImage_AllocateT(FIT_UINT16, width, height);
 73	if(!dst) {
 74		if(src != dib) {
 75			FreeImage_Unload(src);
 76		}
 77		return NULL;
 78	}
 79
 80	// copy metadata from src to dst
 81	FreeImage_CloneMetadata(dst, src);
 82
 83	// convert from src type to UINT16
 84
 85	switch(src_type) {
 86		case FIT_BITMAP:
 87		{
 88			for(unsigned y = 0; y < height; y++) {
 89				const BYTE *src_bits = (BYTE*)FreeImage_GetScanLine(src, y);
 90				WORD *dst_bits = (WORD*)FreeImage_GetScanLine(dst, y);
 91				for(unsigned x = 0; x < width; x++) {
 92					dst_bits[x] = src_bits[x] << 8;
 93				}
 94			}
 95		}
 96		break;
 97
 98		case FIT_RGB16:
 99		{
100			for(unsigned y = 0; y < height; y++) {
101				const FIRGB16 *src_bits = (FIRGB16*)FreeImage_GetScanLine(src, y);
102				WORD *dst_bits = (WORD*)FreeImage_GetScanLine(dst, y);
103				for(unsigned x = 0; x < width; x++) {
104					// convert to grey
105					dst_bits[x] = (WORD)LUMA_REC709(src_bits[x].red, src_bits[x].green, src_bits[x].blue);
106				}
107			}
108		}
109		break;
110
111		case FIT_RGBA16:
112		{
113			for(unsigned y = 0; y < height; y++) {
114				const FIRGBA16 *src_bits = (FIRGBA16*)FreeImage_GetScanLine(src, y);
115				WORD *dst_bits = (WORD*)FreeImage_GetScanLine(dst, y);
116				for(unsigned x = 0; x < width; x++) {
117					// convert to grey
118					dst_bits[x] = (WORD)LUMA_REC709(src_bits[x].red, src_bits[x].green, src_bits[x].blue);
119				}
120			}
121		}
122		break;
123
124		default:
125			break;
126	}
127
128	if(src != dib) {
129		FreeImage_Unload(src);
130	}
131
132	return dst;
133}
134