files/Source/FreeImage/J2KHelper.cpp - free_image - Git at Google

 // ==========================================================
 // JPEG2000 helpers
 //
 // 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"
 #include "third_party/openjpeg2/src/lib/openjp2/openjpeg.h"
 #include "J2KHelper.h"

 // --------------------------------------------------------------------------

 static OPJ_UINT64
 _LengthProc(J2KFIO_t *fio) {
 	long start_pos = fio->io->tell_proc(fio->handle);
 	fio->io->seek_proc(fio->handle, 0, SEEK_END);
 	unsigned file_length = fio->io->tell_proc(fio->handle) - start_pos;
 	fio->io->seek_proc(fio->handle, start_pos, SEEK_SET);
 	return (OPJ_UINT64)file_length;
 }

 static OPJ_SIZE_T
 _ReadProc(void *p_buffer, OPJ_SIZE_T p_nb_bytes, void *p_user_data) {
 	J2KFIO_t *fio = (J2KFIO_t*)p_user_data;
 	OPJ_SIZE_T l_nb_read = fio->io->read_proc(p_buffer, 1, (unsigned)p_nb_bytes, fio->handle);
 	return l_nb_read ? l_nb_read : (OPJ_SIZE_T)-1;
 }

 static OPJ_SIZE_T
 _WriteProc(void *p_buffer, OPJ_SIZE_T p_nb_bytes, void *p_user_data) {
 	J2KFIO_t *fio = (J2KFIO_t*)p_user_data;
 	return fio->io->write_proc(p_buffer, 1, (unsigned)p_nb_bytes, fio->handle);
 }

 static OPJ_OFF_T
 _SkipProc(OPJ_OFF_T p_nb_bytes, void *p_user_data) {
 	J2KFIO_t *fio = (J2KFIO_t*)p_user_data;
 	if( fio->io->seek_proc(fio->handle, (long)p_nb_bytes, SEEK_CUR) ) {
 		return -1;
 	}
 	return p_nb_bytes;
 }

 static OPJ_BOOL
 _SeekProc(OPJ_OFF_T p_nb_bytes, FILE * p_user_data) {
 	J2KFIO_t *fio = (J2KFIO_t*)p_user_data;
 	if( fio->io->seek_proc(fio->handle, (long)p_nb_bytes, SEEK_SET) ) {
 		return OPJ_FALSE;
 	}
 	return OPJ_TRUE;
 }

 // --------------------------------------------------------------------------

 J2KFIO_t*
 opj_freeimage_stream_create(FreeImageIO *io, fi_handle handle, BOOL bRead) {
 	if(!handle) {
 		return NULL;
 	}
 	J2KFIO_t *fio = (J2KFIO_t*)malloc(sizeof(J2KFIO_t));
 	if(fio) {
 		fio->io = io;
 		fio->handle = handle;

 		opj_stream_t *l_stream = opj_stream_create(OPJ_J2K_STREAM_CHUNK_SIZE, bRead ? OPJ_TRUE : OPJ_FALSE);
 		if (l_stream) {
 			opj_stream_set_user_data(l_stream, fio, NULL);
 			opj_stream_set_user_data_length(l_stream, _LengthProc(fio));
 			opj_stream_set_read_function(l_stream, (opj_stream_read_fn)_ReadProc);
 			opj_stream_set_write_function(l_stream, (opj_stream_write_fn)_WriteProc);
 			opj_stream_set_skip_function(l_stream, (opj_stream_skip_fn)_SkipProc);
 			opj_stream_set_seek_function(l_stream, (opj_stream_seek_fn)_SeekProc);
 			fio->stream = l_stream;
 			return fio;
 		} else {
 			free(fio);
 		}
 	}

 	return NULL;
 }

 void
 opj_freeimage_stream_destroy(J2KFIO_t* fio) {
 	if(fio) {
 		if(fio->stream) {
 			opj_stream_destroy(fio->stream);
 		}
 		free(fio);
 	}
 }

 // --------------------------------------------------------------------------

 /**
 Divide an integer by a power of 2 and round upwards
 @return Returns a divided by 2^b
 */
 static int int_ceildivpow2(int a, int b) {
 	return (a + (1 << b) - 1) >> b;
 }

 /**
 Convert a OpenJPEG image to a FIBITMAP
 @param format_id Plugin ID
 @param image OpenJPEG image
 @param header_only If TRUE, allocate a 'header only' FIBITMAP, otherwise allocate a full FIBITMAP
 @return Returns the converted image if successful, returns NULL otherwise
 */
 FIBITMAP* J2KImageToFIBITMAP(int format_id, const opj_image_t *image, BOOL header_only) {
 	FIBITMAP *dib = NULL;

 	try {
 		// compute image width and height

 		//int w = int_ceildiv(image->x1 - image->x0, image->comps[0].dx);
 		int wr = image->comps[0].w;
 		int wrr = int_ceildivpow2(image->comps[0].w, image->comps[0].factor);

 		//int h = int_ceildiv(image->y1 - image->y0, image->comps[0].dy);
 		//int hr = image->comps[0].h;
 		int hrr = int_ceildivpow2(image->comps[0].h, image->comps[0].factor);

 		// check the number of components

 		int numcomps = image->numcomps;

 		BOOL bIsValid = TRUE;
 		for(int c = 0; c < numcomps - 1; c++) {
 			if(	(image->comps[c].dx == image->comps[c+1].dx) &&
 				(image->comps[c].dy == image->comps[c+1].dy) &&
 				(image->comps[c].prec == image->comps[c+1].prec) ) {
 				continue;
 			} else {
 				bIsValid = FALSE;
 				break;
 			}
 		}
 		bIsValid &= ((numcomps == 1) || (numcomps == 3) || (numcomps == 4));
 		if(!bIsValid) {
 			if(numcomps) {
 				FreeImage_OutputMessageProc(format_id, "Warning: image contains %d greyscale components. Only the first will be loaded.\n", numcomps);
 				numcomps = 1;
 			} else {
 				// unknown type
 				throw FI_MSG_ERROR_UNSUPPORTED_FORMAT;
 			}
 		}

 		// create a new DIB

 		if(image->comps[0].prec <= 8) {
 			switch(numcomps) {
 				case 1:
 					dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 8);
 					break;
 				case 3:
 					dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 24, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
 					break;
 				case 4:
 					dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 32, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
 					break;
 			}
 		} else if(image->comps[0].prec <= 16) {
 			switch(numcomps) {
 				case 1:
 					dib = FreeImage_AllocateHeaderT(header_only, FIT_UINT16, wrr, hrr);
 					break;
 				case 3:
 					dib = FreeImage_AllocateHeaderT(header_only, FIT_RGB16, wrr, hrr);
 					break;
 				case 4:
 					dib = FreeImage_AllocateHeaderT(header_only, FIT_RGBA16, wrr, hrr);
 					break;
 			}
 		} else {
 			throw FI_MSG_ERROR_UNSUPPORTED_FORMAT;
 		}
 		if(!dib) {
 			throw FI_MSG_ERROR_DIB_MEMORY;
 		}

 		// "header only" FIBITMAP ?
 		if(header_only) {
 			return dib;
 		}

 		if(image->comps[0].prec <= 8) {
 			if(numcomps == 1) {
 				// 8-bit greyscale
 				// ----------------------------------------------------------

 				// build a greyscale palette

 				RGBQUAD *pal = FreeImage_GetPalette(dib);
 				for (int i = 0; i < 256; i++) {
 					pal[i].rgbRed	= (BYTE)i;
 					pal[i].rgbGreen = (BYTE)i;
 					pal[i].rgbBlue	= (BYTE)i;
 				}

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int index = image->comps[0].data[pixel_pos];
 						index += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						bits[x] = (BYTE)index;

 						pixel_count++;
 					}
 				}
 			}
 			else if(numcomps == 3) {

 				// 24-bit RGB
 				// ----------------------------------------------------------

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int r = image->comps[0].data[pixel_pos];
 						r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						int g = image->comps[1].data[pixel_pos];
 						g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

 						int b = image->comps[2].data[pixel_pos];
 						b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

 						bits[FI_RGBA_RED]   = (BYTE)r;
 						bits[FI_RGBA_GREEN] = (BYTE)g;
 						bits[FI_RGBA_BLUE]  = (BYTE)b;
 						bits += 3;

 						pixel_count++;
 					}
 				}
 			}
 			else if(numcomps == 4) {

 				// 32-bit RGBA
 				// ----------------------------------------------------------

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int r = image->comps[0].data[pixel_pos];
 						r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						int g = image->comps[1].data[pixel_pos];
 						g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

 						int b = image->comps[2].data[pixel_pos];
 						b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

 						int a = image->comps[3].data[pixel_pos];
 						a += (image->comps[3].sgnd ? 1 << (image->comps[3].prec - 1) : 0);

 						bits[FI_RGBA_RED]   = (BYTE)r;
 						bits[FI_RGBA_GREEN] = (BYTE)g;
 						bits[FI_RGBA_BLUE]  = (BYTE)b;
 						bits[FI_RGBA_ALPHA] = (BYTE)a;
 						bits += 4;

 						pixel_count++;
 					}
 				}
 			}
 		}
 		else if(image->comps[0].prec <= 16) {
 			if(numcomps == 1) {
 				// 16-bit greyscale
 				// ----------------------------------------------------------

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					WORD *bits = (WORD*)FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int index = image->comps[0].data[pixel_pos];
 						index += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						bits[x] = (WORD)index;

 						pixel_count++;
 					}
 				}
 			}
 			else if(numcomps == 3) {

 				// 48-bit RGB
 				// ----------------------------------------------------------

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					FIRGB16 *bits = (FIRGB16*)FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int r = image->comps[0].data[pixel_pos];
 						r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						int g = image->comps[1].data[pixel_pos];
 						g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

 						int b = image->comps[2].data[pixel_pos];
 						b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

 						bits[x].red   = (WORD)r;
 						bits[x].green = (WORD)g;
 						bits[x].blue  = (WORD)b;

 						pixel_count++;
 					}
 				}
 			}
 			else if(numcomps == 4) {

 				// 64-bit RGBA
 				// ----------------------------------------------------------

 				// load pixel data

 				unsigned pixel_count = 0;

 				for(int y = 0; y < hrr; y++) {
 					FIRGBA16 *bits = (FIRGBA16*)FreeImage_GetScanLine(dib, hrr - 1 - y);

 					for(int x = 0; x < wrr; x++) {
 						const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

 						int r = image->comps[0].data[pixel_pos];
 						r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

 						int g = image->comps[1].data[pixel_pos];
 						g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

 						int b = image->comps[2].data[pixel_pos];
 						b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

 						int a = image->comps[3].data[pixel_pos];
 						a += (image->comps[3].sgnd ? 1 << (image->comps[3].prec - 1) : 0);

 						bits[x].red   = (WORD)r;
 						bits[x].green = (WORD)g;
 						bits[x].blue  = (WORD)b;
 						bits[x].alpha = (WORD)a;

 						pixel_count++;
 					}
 				}
 			}
 		}

 		return dib;

 	} catch(const char *text) {
 		if(dib) FreeImage_Unload(dib);
 		FreeImage_OutputMessageProc(format_id, text);
 		return NULL;
 	}

 }

 /**
 Convert a FIBITMAP to a OpenJPEG image
 @param format_id Plugin ID
 @param dib FreeImage image
 @param parameters Compression parameters
 @return Returns the converted image if successful, returns NULL otherwise
 */
 opj_image_t* FIBITMAPToJ2KImage(int format_id, FIBITMAP *dib, const opj_cparameters_t *parameters) {
 	int prec, numcomps, x, y, index;
 	OPJ_COLOR_SPACE color_space;
 	opj_image_cmptparm_t cmptparm[4];	// maximum of 4 components
 	opj_image_t *image = NULL;			// image to encode

 	try {
 		int w = FreeImage_GetWidth(dib);
 		int h = FreeImage_GetHeight(dib);

 		// get image characteristics
 		FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(dib);

 		if(image_type == FIT_BITMAP) {
 			// standard image ...
 			prec = 8;
 			switch(FreeImage_GetColorType(dib)) {
 				case FIC_MINISBLACK:
 					numcomps = 1;
 					color_space = OPJ_CLRSPC_GRAY;
 					break;
 				case FIC_RGB:
 					if(FreeImage_GetBPP(dib) == 32) {
 						// 32-bit image with a fully opaque layer
 						numcomps = 4;
 						color_space = OPJ_CLRSPC_SRGB;
 					} else {
 						// 24-bit image
 						numcomps = 3;
 						color_space = OPJ_CLRSPC_SRGB;
 					}
 					break;
 				case FIC_RGBALPHA:
 					numcomps = 4;
 					color_space = OPJ_CLRSPC_SRGB;
 					break;
 				default:
 					return NULL;
 			}
 		} else {
 			// HDR image ...
 			prec = 16;
 			switch(image_type) {
 				case FIT_UINT16:
 					numcomps = 1;
 					color_space = OPJ_CLRSPC_GRAY;
 					break;
 				case FIT_RGB16:
 					numcomps = 3;
 					color_space = OPJ_CLRSPC_SRGB;
 					break;
 				case FIT_RGBA16:
 					numcomps = 4;
 					color_space = OPJ_CLRSPC_SRGB;
 					break;
 				default:
 					return NULL;
 			}
 		}

 		// initialize image components
 		memset(&cmptparm[0], 0, 4 * sizeof(opj_image_cmptparm_t));
 		for(int i = 0; i < numcomps; i++) {
 			cmptparm[i].dx = parameters->subsampling_dx;
 			cmptparm[i].dy = parameters->subsampling_dy;
 			cmptparm[i].w = w;
 			cmptparm[i].h = h;
 			cmptparm[i].prec = prec;
 			cmptparm[i].bpp = prec;
 			cmptparm[i].sgnd = 0;
 		}
 		// create the image
 		image = opj_image_create(numcomps, &cmptparm[0], color_space);
 		if(!image) {
 			throw FI_MSG_ERROR_DIB_MEMORY;
 		}

 		// set image offset and reference grid
 		image->x0 = parameters->image_offset_x0;
 		image->y0 = parameters->image_offset_y0;
 		image->x1 = parameters->image_offset_x0 + (w - 1) *	parameters->subsampling_dx + 1;
 		image->y1 = parameters->image_offset_y0 + (h - 1) *	parameters->subsampling_dy + 1;

 		// set image data
 		if(prec == 8) {
 			switch(numcomps) {
 				case 1:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[x];
 							index++;
 						}
 					}
 					break;
 				case 3:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[FI_RGBA_RED];
 							image->comps[1].data[index] = bits[FI_RGBA_GREEN];
 							image->comps[2].data[index] = bits[FI_RGBA_BLUE];
 							bits += 3;
 							index++;
 						}
 					}
 					break;
 				case 4:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[FI_RGBA_RED];
 							image->comps[1].data[index] = bits[FI_RGBA_GREEN];
 							image->comps[2].data[index] = bits[FI_RGBA_BLUE];
 							image->comps[3].data[index] = bits[FI_RGBA_ALPHA];
 							bits += 4;
 							index++;
 						}
 					}
 					break;
 			}
 		}
 		else if(prec == 16) {
 			switch(numcomps) {
 				case 1:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						WORD *bits = (WORD*)FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[x];
 							index++;
 						}
 					}
 					break;
 				case 3:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						FIRGB16 *bits = (FIRGB16*)FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[x].red;
 							image->comps[1].data[index] = bits[x].green;
 							image->comps[2].data[index] = bits[x].blue;
 							index++;
 						}
 					}
 					break;
 				case 4:
 					index = 0;
 					for(y = 0; y < h; y++) {
 						FIRGBA16 *bits = (FIRGBA16*)FreeImage_GetScanLine(dib, h - 1 - y);
 						for(x = 0; x < w; x++) {
 							image->comps[0].data[index] = bits[x].red;
 							image->comps[1].data[index] = bits[x].green;
 							image->comps[2].data[index] = bits[x].blue;
 							image->comps[3].data[index] = bits[x].alpha;
 							index++;
 						}
 					}
 					break;
 			}
 		}

 		return image;

 	} catch (const char *text) {
 		if(image) opj_image_destroy(image);
 		FreeImage_OutputMessageProc(format_id, text);
 		return NULL;
 	}
 }
	// ==========================================================
	// JPEG2000 helpers
	//
	// 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"
	#include "third_party/openjpeg2/src/lib/openjp2/openjpeg.h"
	#include "J2KHelper.h"

	// --------------------------------------------------------------------------

	static OPJ_UINT64
	_LengthProc(J2KFIO_t *fio) {
	long start_pos = fio->io->tell_proc(fio->handle);
	fio->io->seek_proc(fio->handle, 0, SEEK_END);
	unsigned file_length = fio->io->tell_proc(fio->handle) - start_pos;
	fio->io->seek_proc(fio->handle, start_pos, SEEK_SET);
	return (OPJ_UINT64)file_length;
	}

	static OPJ_SIZE_T
	_ReadProc(void p_buffer, OPJ_SIZE_T p_nb_bytes, void p_user_data) {
	J2KFIO_t fio = (J2KFIO_t)p_user_data;
	OPJ_SIZE_T l_nb_read = fio->io->read_proc(p_buffer, 1, (unsigned)p_nb_bytes, fio->handle);
	return l_nb_read ? l_nb_read : (OPJ_SIZE_T)-1;
	}

	static OPJ_SIZE_T
	_WriteProc(void p_buffer, OPJ_SIZE_T p_nb_bytes, void p_user_data) {
	J2KFIO_t fio = (J2KFIO_t)p_user_data;
	return fio->io->write_proc(p_buffer, 1, (unsigned)p_nb_bytes, fio->handle);
	}

	static OPJ_OFF_T
	_SkipProc(OPJ_OFF_T p_nb_bytes, void *p_user_data) {
	J2KFIO_t fio = (J2KFIO_t)p_user_data;
	if( fio->io->seek_proc(fio->handle, (long)p_nb_bytes, SEEK_CUR) ) {
	return -1;
	}
	return p_nb_bytes;
	}

	static OPJ_BOOL
	_SeekProc(OPJ_OFF_T p_nb_bytes, FILE * p_user_data) {
	J2KFIO_t fio = (J2KFIO_t)p_user_data;
	if( fio->io->seek_proc(fio->handle, (long)p_nb_bytes, SEEK_SET) ) {
	return OPJ_FALSE;
	}
	return OPJ_TRUE;
	}

	// --------------------------------------------------------------------------

	J2KFIO_t*
	opj_freeimage_stream_create(FreeImageIO *io, fi_handle handle, BOOL bRead) {
	if(!handle) {
	return NULL;
	}
	J2KFIO_t fio = (J2KFIO_t)malloc(sizeof(J2KFIO_t));
	if(fio) {
	fio->io = io;
	fio->handle = handle;

	opj_stream_t *l_stream = opj_stream_create(OPJ_J2K_STREAM_CHUNK_SIZE, bRead ? OPJ_TRUE : OPJ_FALSE);
	if (l_stream) {
	opj_stream_set_user_data(l_stream, fio, NULL);
	opj_stream_set_user_data_length(l_stream, _LengthProc(fio));
	opj_stream_set_read_function(l_stream, (opj_stream_read_fn)_ReadProc);
	opj_stream_set_write_function(l_stream, (opj_stream_write_fn)_WriteProc);
	opj_stream_set_skip_function(l_stream, (opj_stream_skip_fn)_SkipProc);
	opj_stream_set_seek_function(l_stream, (opj_stream_seek_fn)_SeekProc);
	fio->stream = l_stream;
	return fio;
	} else {
	free(fio);
	}
	}

	return NULL;
	}

	void
	opj_freeimage_stream_destroy(J2KFIO_t* fio) {
	if(fio) {
	if(fio->stream) {
	opj_stream_destroy(fio->stream);
	}
	free(fio);
	}
	}

	// --------------------------------------------------------------------------

	/**
	Divide an integer by a power of 2 and round upwards
	@return Returns a divided by 2^b
	*/
	static int int_ceildivpow2(int a, int b) {
	return (a + (1 << b) - 1) >> b;
	}

	/**
	Convert a OpenJPEG image to a FIBITMAP
	@param format_id Plugin ID
	@param image OpenJPEG image
	@param header_only If TRUE, allocate a 'header only' FIBITMAP, otherwise allocate a full FIBITMAP
	@return Returns the converted image if successful, returns NULL otherwise
	*/
	FIBITMAP* J2KImageToFIBITMAP(int format_id, const opj_image_t *image, BOOL header_only) {
	FIBITMAP *dib = NULL;

	try {
	// compute image width and height

	//int w = int_ceildiv(image->x1 - image->x0, image->comps[0].dx);
	int wr = image->comps[0].w;
	int wrr = int_ceildivpow2(image->comps[0].w, image->comps[0].factor);

	//int h = int_ceildiv(image->y1 - image->y0, image->comps[0].dy);
	//int hr = image->comps[0].h;
	int hrr = int_ceildivpow2(image->comps[0].h, image->comps[0].factor);

	// check the number of components

	int numcomps = image->numcomps;

	BOOL bIsValid = TRUE;
	for(int c = 0; c < numcomps - 1; c++) {
	if( (image->comps[c].dx == image->comps[c+1].dx) &&
	(image->comps[c].dy == image->comps[c+1].dy) &&
	(image->comps[c].prec == image->comps[c+1].prec) ) {
	continue;
	} else {
	bIsValid = FALSE;
	break;
	}
	}
	bIsValid &= ((numcomps == 1) \|\| (numcomps == 3) \|\| (numcomps == 4));
	if(!bIsValid) {
	if(numcomps) {
	FreeImage_OutputMessageProc(format_id, "Warning: image contains %d greyscale components. Only the first will be loaded.\n", numcomps);
	numcomps = 1;
	} else {
	// unknown type
	throw FI_MSG_ERROR_UNSUPPORTED_FORMAT;
	}
	}

	// create a new DIB

	if(image->comps[0].prec <= 8) {
	switch(numcomps) {
	case 1:
	dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 8);
	break;
	case 3:
	dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 24, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
	break;
	case 4:
	dib = FreeImage_AllocateHeader(header_only, wrr, hrr, 32, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
	break;
	}
	} else if(image->comps[0].prec <= 16) {
	switch(numcomps) {
	case 1:
	dib = FreeImage_AllocateHeaderT(header_only, FIT_UINT16, wrr, hrr);
	break;
	case 3:
	dib = FreeImage_AllocateHeaderT(header_only, FIT_RGB16, wrr, hrr);
	break;
	case 4:
	dib = FreeImage_AllocateHeaderT(header_only, FIT_RGBA16, wrr, hrr);
	break;
	}
	} else {
	throw FI_MSG_ERROR_UNSUPPORTED_FORMAT;
	}
	if(!dib) {
	throw FI_MSG_ERROR_DIB_MEMORY;
	}

	// "header only" FIBITMAP ?
	if(header_only) {
	return dib;
	}

	if(image->comps[0].prec <= 8) {
	if(numcomps == 1) {
	// 8-bit greyscale
	// ----------------------------------------------------------

	// build a greyscale palette

	RGBQUAD *pal = FreeImage_GetPalette(dib);
	for (int i = 0; i < 256; i++) {
	pal[i].rgbRed = (BYTE)i;
	pal[i].rgbGreen = (BYTE)i;
	pal[i].rgbBlue = (BYTE)i;
	}

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int index = image->comps[0].data[pixel_pos];
	index += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	bits[x] = (BYTE)index;

	pixel_count++;
	}
	}
	}
	else if(numcomps == 3) {

	// 24-bit RGB
	// ----------------------------------------------------------

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int r = image->comps[0].data[pixel_pos];
	r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	int g = image->comps[1].data[pixel_pos];
	g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

	int b = image->comps[2].data[pixel_pos];
	b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

	bits[FI_RGBA_RED] = (BYTE)r;
	bits[FI_RGBA_GREEN] = (BYTE)g;
	bits[FI_RGBA_BLUE] = (BYTE)b;
	bits += 3;

	pixel_count++;
	}
	}
	}
	else if(numcomps == 4) {

	// 32-bit RGBA
	// ----------------------------------------------------------

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int r = image->comps[0].data[pixel_pos];
	r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	int g = image->comps[1].data[pixel_pos];
	g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

	int b = image->comps[2].data[pixel_pos];
	b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

	int a = image->comps[3].data[pixel_pos];
	a += (image->comps[3].sgnd ? 1 << (image->comps[3].prec - 1) : 0);

	bits[FI_RGBA_RED] = (BYTE)r;
	bits[FI_RGBA_GREEN] = (BYTE)g;
	bits[FI_RGBA_BLUE] = (BYTE)b;
	bits[FI_RGBA_ALPHA] = (BYTE)a;
	bits += 4;

	pixel_count++;
	}
	}
	}
	}
	else if(image->comps[0].prec <= 16) {
	if(numcomps == 1) {
	// 16-bit greyscale
	// ----------------------------------------------------------

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	WORD bits = (WORD)FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int index = image->comps[0].data[pixel_pos];
	index += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	bits[x] = (WORD)index;

	pixel_count++;
	}
	}
	}
	else if(numcomps == 3) {

	// 48-bit RGB
	// ----------------------------------------------------------

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	FIRGB16 bits = (FIRGB16)FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int r = image->comps[0].data[pixel_pos];
	r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	int g = image->comps[1].data[pixel_pos];
	g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

	int b = image->comps[2].data[pixel_pos];
	b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

	bits[x].red = (WORD)r;
	bits[x].green = (WORD)g;
	bits[x].blue = (WORD)b;

	pixel_count++;
	}
	}
	}
	else if(numcomps == 4) {

	// 64-bit RGBA
	// ----------------------------------------------------------

	// load pixel data

	unsigned pixel_count = 0;

	for(int y = 0; y < hrr; y++) {
	FIRGBA16 bits = (FIRGBA16)FreeImage_GetScanLine(dib, hrr - 1 - y);

	for(int x = 0; x < wrr; x++) {
	const unsigned pixel_pos = pixel_count / wrr * wr + pixel_count % wrr;

	int r = image->comps[0].data[pixel_pos];
	r += (image->comps[0].sgnd ? 1 << (image->comps[0].prec - 1) : 0);

	int g = image->comps[1].data[pixel_pos];
	g += (image->comps[1].sgnd ? 1 << (image->comps[1].prec - 1) : 0);

	int b = image->comps[2].data[pixel_pos];
	b += (image->comps[2].sgnd ? 1 << (image->comps[2].prec - 1) : 0);

	int a = image->comps[3].data[pixel_pos];
	a += (image->comps[3].sgnd ? 1 << (image->comps[3].prec - 1) : 0);

	bits[x].red = (WORD)r;
	bits[x].green = (WORD)g;
	bits[x].blue = (WORD)b;
	bits[x].alpha = (WORD)a;

	pixel_count++;
	}
	}
	}
	}

	return dib;

	} catch(const char *text) {
	if(dib) FreeImage_Unload(dib);
	FreeImage_OutputMessageProc(format_id, text);
	return NULL;
	}

	}

	/**
	Convert a FIBITMAP to a OpenJPEG image
	@param format_id Plugin ID
	@param dib FreeImage image
	@param parameters Compression parameters
	@return Returns the converted image if successful, returns NULL otherwise
	*/
	opj_image_t* FIBITMAPToJ2KImage(int format_id, FIBITMAP dib, const opj_cparameters_t parameters) {
	int prec, numcomps, x, y, index;
	OPJ_COLOR_SPACE color_space;
	opj_image_cmptparm_t cmptparm[4]; // maximum of 4 components
	opj_image_t *image = NULL; // image to encode

	try {
	int w = FreeImage_GetWidth(dib);
	int h = FreeImage_GetHeight(dib);

	// get image characteristics
	FREE_IMAGE_TYPE image_type = FreeImage_GetImageType(dib);

	if(image_type == FIT_BITMAP) {
	// standard image ...
	prec = 8;
	switch(FreeImage_GetColorType(dib)) {
	case FIC_MINISBLACK:
	numcomps = 1;
	color_space = OPJ_CLRSPC_GRAY;
	break;
	case FIC_RGB:
	if(FreeImage_GetBPP(dib) == 32) {
	// 32-bit image with a fully opaque layer
	numcomps = 4;
	color_space = OPJ_CLRSPC_SRGB;
	} else {
	// 24-bit image
	numcomps = 3;
	color_space = OPJ_CLRSPC_SRGB;
	}
	break;
	case FIC_RGBALPHA:
	numcomps = 4;
	color_space = OPJ_CLRSPC_SRGB;
	break;
	default:
	return NULL;
	}
	} else {
	// HDR image ...
	prec = 16;
	switch(image_type) {
	case FIT_UINT16:
	numcomps = 1;
	color_space = OPJ_CLRSPC_GRAY;
	break;
	case FIT_RGB16:
	numcomps = 3;
	color_space = OPJ_CLRSPC_SRGB;
	break;
	case FIT_RGBA16:
	numcomps = 4;
	color_space = OPJ_CLRSPC_SRGB;
	break;
	default:
	return NULL;
	}
	}

	// initialize image components
	memset(&cmptparm[0], 0, 4 * sizeof(opj_image_cmptparm_t));
	for(int i = 0; i < numcomps; i++) {
	cmptparm[i].dx = parameters->subsampling_dx;
	cmptparm[i].dy = parameters->subsampling_dy;
	cmptparm[i].w = w;
	cmptparm[i].h = h;
	cmptparm[i].prec = prec;
	cmptparm[i].bpp = prec;
	cmptparm[i].sgnd = 0;
	}
	// create the image
	image = opj_image_create(numcomps, &cmptparm[0], color_space);
	if(!image) {
	throw FI_MSG_ERROR_DIB_MEMORY;
	}

	// set image offset and reference grid
	image->x0 = parameters->image_offset_x0;
	image->y0 = parameters->image_offset_y0;
	image->x1 = parameters->image_offset_x0 + (w - 1) * parameters->subsampling_dx + 1;
	image->y1 = parameters->image_offset_y0 + (h - 1) * parameters->subsampling_dy + 1;

	// set image data
	if(prec == 8) {
	switch(numcomps) {
	case 1:
	index = 0;
	for(y = 0; y < h; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[x];
	index++;
	}
	}
	break;
	case 3:
	index = 0;
	for(y = 0; y < h; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[FI_RGBA_RED];
	image->comps[1].data[index] = bits[FI_RGBA_GREEN];
	image->comps[2].data[index] = bits[FI_RGBA_BLUE];
	bits += 3;
	index++;
	}
	}
	break;
	case 4:
	index = 0;
	for(y = 0; y < h; y++) {
	BYTE *bits = FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[FI_RGBA_RED];
	image->comps[1].data[index] = bits[FI_RGBA_GREEN];
	image->comps[2].data[index] = bits[FI_RGBA_BLUE];
	image->comps[3].data[index] = bits[FI_RGBA_ALPHA];
	bits += 4;
	index++;
	}
	}
	break;
	}
	}
	else if(prec == 16) {
	switch(numcomps) {
	case 1:
	index = 0;
	for(y = 0; y < h; y++) {
	WORD bits = (WORD)FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[x];
	index++;
	}
	}
	break;
	case 3:
	index = 0;
	for(y = 0; y < h; y++) {
	FIRGB16 bits = (FIRGB16)FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[x].red;
	image->comps[1].data[index] = bits[x].green;
	image->comps[2].data[index] = bits[x].blue;
	index++;
	}
	}
	break;
	case 4:
	index = 0;
	for(y = 0; y < h; y++) {
	FIRGBA16 bits = (FIRGBA16)FreeImage_GetScanLine(dib, h - 1 - y);
	for(x = 0; x < w; x++) {
	image->comps[0].data[index] = bits[x].red;
	image->comps[1].data[index] = bits[x].green;
	image->comps[2].data[index] = bits[x].blue;
	image->comps[3].data[index] = bits[x].alpha;
	index++;
	}
	}
	break;
	}
	}

	return image;

	} catch (const char *text) {
	if(image) opj_image_destroy(image);
	FreeImage_OutputMessageProc(format_id, text);
	return NULL;
	}
	}