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📄 jpg_dec.c

📁 JPEG2000是以小波变换为基础
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/* * Copyright (c) 2001-2003 Michael David Adams. * All rights reserved. *//* __START_OF_JASPER_LICENSE__ *  * JasPer License Version 2.0 *  * Copyright (c) 2001-2006 Michael David Adams * Copyright (c) 1999-2000 Image Power, Inc. * Copyright (c) 1999-2000 The University of British Columbia *  * All rights reserved. *  * Permission is hereby granted, free of charge, to any person (the * "User") obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without restriction, * including without limitation the rights to use, copy, modify, merge, * publish, distribute, and/or sell copies of the Software, and to permit * persons to whom the Software is furnished to do so, subject to the * following conditions: *  * 1.  The above copyright notices and this permission notice (which * includes the disclaimer below) shall be included in all copies or * substantial portions of the Software. *  * 2.  The name of a copyright holder shall not be used to endorse or * promote products derived from the Software without specific prior * written permission. *  * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS * LICENSE.  NO USE OF THE SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER * THIS DISCLAIMER.  THE SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS * "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A * PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.  IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL * INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.  NO ASSURANCES ARE * PROVIDED BY THE COPYRIGHT HOLDERS THAT THE SOFTWARE DOES NOT INFRINGE * THE PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS OF ANY OTHER ENTITY. * EACH COPYRIGHT HOLDER DISCLAIMS ANY LIABILITY TO THE USER FOR CLAIMS * BROUGHT BY ANY OTHER ENTITY BASED ON INFRINGEMENT OF INTELLECTUAL * PROPERTY RIGHTS OR OTHERWISE.  AS A CONDITION TO EXERCISING THE RIGHTS * GRANTED HEREUNDER, EACH USER HEREBY ASSUMES SOLE RESPONSIBILITY TO SECURE * ANY OTHER INTELLECTUAL PROPERTY RIGHTS NEEDED, IF ANY.  THE SOFTWARE * IS NOT FAULT-TOLERANT AND IS NOT INTENDED FOR USE IN MISSION-CRITICAL * SYSTEMS, SUCH AS THOSE USED IN THE OPERATION OF NUCLEAR FACILITIES, * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL * SYSTEMS, DIRECT LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH * THE FAILURE OF THE SOFTWARE OR SYSTEM COULD LEAD DIRECTLY TO DEATH, * PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH * RISK ACTIVITIES").  THE COPYRIGHT HOLDERS SPECIFICALLY DISCLAIM ANY * EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES. *  * __END_OF_JASPER_LICENSE__ *//******************************************************************************\* Includes.\******************************************************************************/#include <stdio.h>#include <assert.h>#include <ctype.h>#include "jasper/jas_tvp.h"#include "jasper/jas_stream.h"#include "jasper/jas_image.h"#include "jasper/jas_string.h"#include "jpg_jpeglib.h"#include "jpg_cod.h"/******************************************************************************\* Types.\******************************************************************************//* JPEG decoder data sink type. */typedef struct jpg_dest_s {	/* Initialize output. */	void (*start_output)(j_decompress_ptr cinfo, struct jpg_dest_s *dinfo);	/* Output rows of decompressed data. */	void (*put_pixel_rows)(j_decompress_ptr cinfo, struct jpg_dest_s *dinfo,	  JDIMENSION rows_supplied);	/* Cleanup output. */	void (*finish_output)(j_decompress_ptr cinfo, struct jpg_dest_s *dinfo);	/* Output buffer. */	JSAMPARRAY buffer;	/* Height of output buffer. */	JDIMENSION buffer_height;	/* The current row. */	JDIMENSION row;	/* The image used to hold the decompressed sample data. */	jas_image_t *image;	/* The row buffer. */	jas_matrix_t *data;	/* The error indicator.  If this is nonzero, something has gone wrong	  during decompression. */	int error;} jpg_dest_t;/******************************************************************************\* Local functions.\******************************************************************************/static void jpg_start_output(j_decompress_ptr cinfo, jpg_dest_t *dinfo);static void jpg_put_pixel_rows(j_decompress_ptr cinfo, jpg_dest_t *dinfo,  JDIMENSION rows_supplied);static void jpg_finish_output(j_decompress_ptr cinfo, jpg_dest_t *dinfo);static int jpg_copystreamtofile(FILE *out, jas_stream_t *in);static jas_image_t *jpg_mkimage(j_decompress_ptr cinfo);/******************************************************************************\* Code for load operation.\******************************************************************************//* Load an image from a stream in the JPG format. */jas_image_t *jpg_decode(jas_stream_t *in, char *optstr){	struct jpeg_decompress_struct cinfo;	struct jpeg_error_mgr jerr;	FILE *input_file;	jpg_dest_t dest_mgr_buf;	jpg_dest_t *dest_mgr = &dest_mgr_buf;	int num_scanlines;	jas_image_t *image;	/* Avoid compiler warnings about unused parameters. */	optstr = 0;	image = 0;	input_file = 0;	if (!(input_file = tmpfile())) {		goto error;	}	if (jpg_copystreamtofile(input_file, in)) {		goto error;	}	rewind(input_file);	/* Allocate and initialize a JPEG decompression object. */	cinfo.err = jpeg_std_error(&jerr);	jpeg_create_decompress(&cinfo);	/* Specify the data source for decompression. */	jpeg_stdio_src(&cinfo, input_file);	/* Read the file header to obtain the image information. */	jpeg_read_header(&cinfo, TRUE);	/* Start the decompressor. */	jpeg_start_decompress(&cinfo);	/* Create an image object to hold the decoded data. */	if (!(image = jpg_mkimage(&cinfo))) {		goto error;	}	/* Initialize the data sink object. */	dest_mgr->image = image;	dest_mgr->data = jas_matrix_create(1, cinfo.output_width);	dest_mgr->start_output = jpg_start_output;	dest_mgr->put_pixel_rows = jpg_put_pixel_rows;	dest_mgr->finish_output = jpg_finish_output;    dest_mgr->buffer = (*cinfo.mem->alloc_sarray)      ((j_common_ptr) &cinfo, JPOOL_IMAGE,       cinfo.output_width * cinfo.output_components, (JDIMENSION) 1);	dest_mgr->buffer_height = 1;	dest_mgr->error = 0;	/* Process the compressed data. */	(*dest_mgr->start_output)(&cinfo, dest_mgr);	while (cinfo.output_scanline < cinfo.output_height) {		num_scanlines = jpeg_read_scanlines(&cinfo, dest_mgr->buffer,		  dest_mgr->buffer_height);		(*dest_mgr->put_pixel_rows)(&cinfo, dest_mgr, num_scanlines);	}	(*dest_mgr->finish_output)(&cinfo, dest_mgr);	/* Complete the decompression process. */	jpeg_finish_decompress(&cinfo);	/* Destroy the JPEG decompression object. */	jpeg_destroy_decompress(&cinfo);	jas_matrix_destroy(dest_mgr->data);	fclose(input_file);	if (dest_mgr->error) {		goto error;	}	return image;error:	if (image) {		jas_image_destroy(image);	}	if (input_file) {		fclose(input_file);	}	return 0;}/******************************************************************************\*\******************************************************************************/static jas_image_t *jpg_mkimage(j_decompress_ptr cinfo){	jas_image_t *image;	int cmptno;	jas_image_cmptparm_t cmptparm;	int numcmpts;	image = 0;	numcmpts = cinfo->output_components;	if (!(image = jas_image_create0())) {		goto error;	}	for (cmptno = 0; cmptno < numcmpts; ++cmptno) {		cmptparm.tlx = 0;		cmptparm.tly = 0;		cmptparm.hstep = 1;		cmptparm.vstep = 1;		cmptparm.width = cinfo->image_width;		cmptparm.height = cinfo->image_height;		cmptparm.prec = 8;		cmptparm.sgnd = false;		if (jas_image_addcmpt(image, cmptno, &cmptparm)) {			goto error;		}	}	if (numcmpts == 3) {		jas_image_setclrspc(image, JAS_CLRSPC_SRGB);		jas_image_setcmpttype(image, 0,		  JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_RGB_R));		jas_image_setcmpttype(image, 1,		  JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_RGB_G));		jas_image_setcmpttype(image, 2,		  JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_RGB_B));	} else {		jas_image_setclrspc(image, JAS_CLRSPC_SGRAY);		jas_image_setcmpttype(image, 0,		  JAS_IMAGE_CT_COLOR(JAS_CLRSPC_CHANIND_GRAY_Y));	}	return image;error:	if (image) {		jas_image_destroy(image);	}	return 0;}/******************************************************************************\* Data source code.\******************************************************************************/static int jpg_copystreamtofile(FILE *out, jas_stream_t *in){	int c;	while ((c = jas_stream_getc(in)) != EOF) {		if (fputc(c, out) == EOF) {			return -1;		}	}	if (jas_stream_error(in)) {		return -1;	}	return 0;}/******************************************************************************\* Data sink code.\******************************************************************************/static void jpg_start_output(j_decompress_ptr cinfo, jpg_dest_t *dinfo){	/* Avoid compiler warnings about unused parameters. */	cinfo = 0;	dinfo->row = 0;}static void jpg_put_pixel_rows(j_decompress_ptr cinfo, jpg_dest_t *dinfo,  JDIMENSION rows_supplied){	JSAMPLE *bufptr;	int cmptno;	JDIMENSION x;	uint_fast32_t width;	if (dinfo->error) {		return;	}	assert(cinfo->output_components == jas_image_numcmpts(dinfo->image));	for (cmptno = 0; cmptno < cinfo->output_components; ++cmptno) {		width = jas_image_cmptwidth(dinfo->image, cmptno);		bufptr = (dinfo->buffer[0]) + cmptno;		for (x = 0; x < width; ++x) {			jas_matrix_set(dinfo->data, 0, x, GETJSAMPLE(*bufptr));			bufptr += cinfo->output_components;		}		if (jas_image_writecmpt(dinfo->image, cmptno, 0, dinfo->row, width, 1,		  dinfo->data)) {			dinfo->error = 1;		}	}	dinfo->row += rows_supplied;}static void jpg_finish_output(j_decompress_ptr cinfo, jpg_dest_t *dinfo){	/* Avoid compiler warnings about unused parameters. */	cinfo = 0;	dinfo = 0;}

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