blob: 9e28205688b5d9c6b9482aa54d1d63e5788c55fb [file] [log] [blame] [edit]
// ==========================================================
// Bitmap conversion routines
//
// Design and implementation by
// - Hervé Drolon (drolon@infonie.fr)
//
// 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!
// ==========================================================
#include "FreeImage.h"
#include "Utilities.h"
// ----------------------------------------------------------
// smart convert X to RGB16
// ----------------------------------------------------------
FIBITMAP * DLL_CALLCONV
FreeImage_ConvertToRGB16(FIBITMAP *dib) {
FIBITMAP *src = NULL;
FIBITMAP *dst = NULL;
if(!FreeImage_HasPixels(dib)) return NULL;
const FREE_IMAGE_TYPE src_type = FreeImage_GetImageType(dib);
// check for allowed conversions
switch(src_type) {
case FIT_BITMAP:
{
// convert to 24-bit if needed
if((FreeImage_GetBPP(dib) == 24) || (FreeImage_GetBPP(dib) == 32)) {
src = dib;
} else {
src = FreeImage_ConvertTo24Bits(dib);
if(!src) return NULL;
}
break;
}
case FIT_UINT16:
// allow conversion from unsigned 16-bit
src = dib;
break;
case FIT_RGB16:
// RGB16 type : clone the src
return FreeImage_Clone(dib);
break;
case FIT_RGBA16:
// allow conversion from 64-bit RGBA (ignore the alpha channel)
src = dib;
break;
default:
return NULL;
}
// allocate dst image
const unsigned width = FreeImage_GetWidth(src);
const unsigned height = FreeImage_GetHeight(src);
dst = FreeImage_AllocateT(FIT_RGB16, width, height);
if(!dst) {
if(src != dib) {
FreeImage_Unload(src);
}
return NULL;
}
// copy metadata from src to dst
FreeImage_CloneMetadata(dst, src);
// convert from src type to RGB16
switch(src_type) {
case FIT_BITMAP:
{
// Calculate the number of bytes per pixel (1 for 8-bit, 3 for 24-bit or 4 for 32-bit)
const unsigned bytespp = FreeImage_GetLine(src) / FreeImage_GetWidth(src);
for(unsigned y = 0; y < height; y++) {
const BYTE *src_bits = (BYTE*)FreeImage_GetScanLine(src, y);
FIRGB16 *dst_bits = (FIRGB16*)FreeImage_GetScanLine(dst, y);
for(unsigned x = 0; x < width; x++) {
dst_bits[x].red = src_bits[FI_RGBA_RED] << 8;
dst_bits[x].green = src_bits[FI_RGBA_GREEN] << 8;
dst_bits[x].blue = src_bits[FI_RGBA_BLUE] << 8;
src_bits += bytespp;
}
}
}
break;
case FIT_UINT16:
{
for(unsigned y = 0; y < height; y++) {
const WORD *src_bits = (WORD*)FreeImage_GetScanLine(src, y);
FIRGB16 *dst_bits = (FIRGB16*)FreeImage_GetScanLine(dst, y);
for(unsigned x = 0; x < width; x++) {
// convert by copying greyscale channel to each R, G, B channels
dst_bits[x].red = src_bits[x];
dst_bits[x].green = src_bits[x];
dst_bits[x].blue = src_bits[x];
}
}
}
break;
case FIT_RGBA16:
{
for(unsigned y = 0; y < height; y++) {
const FIRGBA16 *src_bits = (FIRGBA16*)FreeImage_GetScanLine(src, y);
FIRGB16 *dst_bits = (FIRGB16*)FreeImage_GetScanLine(dst, y);
for(unsigned x = 0; x < width; x++) {
// convert and skip alpha channel
dst_bits[x].red = src_bits[x].red;
dst_bits[x].green = src_bits[x].green;
dst_bits[x].blue = src_bits[x].blue;
}
}
}
break;
default:
break;
}
if(src != dib) {
FreeImage_Unload(src);
}
return dst;
}