⭐ 欢迎来到虫虫下载站! | 📦 资源下载 📁 资源专辑 ℹ️ 关于我们
⭐ 虫虫下载站

📄 jpg_dec.c

📁 用C语言实现的JPEG编码
💻 C
字号:
/* * Copyright (c) 2001-2003 Michael David Adams. * All rights reserved. *//* __START_OF_JASPER_LICENSE__ *  * JasPer Software License *  * IMAGE POWER JPEG-2000 PUBLIC LICENSE * ************************************ *  * GRANT: *  * Permission is hereby granted, free of charge, to any person (the "User") * obtaining a copy of this software and associated documentation, to deal * in the JasPer Software without restriction, including without limitation * the right to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the JasPer Software (in source and binary forms), * and to permit persons to whom the JasPer Software is furnished to do so, * provided further that the License Conditions below are met. *  * License Conditions * ****************** *  * A.  Redistributions of source code must retain the above copyright notice, * and this list of conditions, and the following disclaimer. *  * B.  Redistributions in binary form must reproduce the above copyright * notice, and this list of conditions, and the following disclaimer in * the documentation and/or other materials provided with the distribution. *  * C.  Neither the name of Image Power, Inc. nor any other contributor * (including, but not limited to, the University of British Columbia and * Michael David Adams) may be used to endorse or promote products derived * from this software without specific prior written permission. *  * D.  User agrees that it shall not commence any action against Image Power, * Inc., the University of British Columbia, Michael David Adams, or any * other contributors (collectively "Licensors") for infringement of any * intellectual property rights ("IPR") held by the User in respect of any * technology that User owns or has a right to license or sublicense and * which is an element required in order to claim compliance with ISO/IEC * 15444-1 (i.e., JPEG-2000 Part 1).  "IPR" means all intellectual property * rights worldwide arising under statutory or common law, and whether * or not perfected, including, without limitation, all (i) patents and * patent applications owned or licensable by User; (ii) rights associated * with works of authorship including copyrights, copyright applications, * copyright registrations, mask work rights, mask work applications, * mask work registrations; (iii) rights relating to the protection of * trade secrets and confidential information; (iv) any right analogous * to those set forth in subsections (i), (ii), or (iii) and any other * proprietary rights relating to intangible property (other than trademark, * trade dress, or service mark rights); and (v) divisions, continuations, * renewals, reissues and extensions of the foregoing (as and to the extent * applicable) now existing, hereafter filed, issued or acquired. *  * E.  If User commences an infringement action against any Licensor(s) then * such Licensor(s) shall have the right to terminate User's license and * all sublicenses that have been granted hereunder by User to other parties. *  * F.  This software is for use only in hardware or software products that * are compliant with ISO/IEC 15444-1 (i.e., JPEG-2000 Part 1).  No license * or right to this Software is granted for products that do not comply * with ISO/IEC 15444-1.  The JPEG-2000 Part 1 standard can be purchased * from the ISO. *  * THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE. * NO USE OF THE JASPER SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER * THIS DISCLAIMER.  THE JASPER SOFTWARE IS PROVIDED BY THE LICENSORS AND * CONTRIBUTORS UNDER THIS LICENSE ON AN ``AS-IS'' BASIS, WITHOUT WARRANTY * OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, * WARRANTIES THAT THE JASPER SOFTWARE IS FREE OF DEFECTS, IS MERCHANTABLE, * IS FIT FOR A PARTICULAR PURPOSE OR IS NON-INFRINGING.  THOSE INTENDING * TO USE THE JASPER SOFTWARE OR MODIFICATIONS THEREOF FOR USE IN HARDWARE * OR SOFTWARE PRODUCTS ARE ADVISED THAT THEIR USE MAY INFRINGE EXISTING * PATENTS, COPYRIGHTS, TRADEMARKS, OR OTHER INTELLECTUAL PROPERTY RIGHTS. * THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE JASPER SOFTWARE * IS WITH THE USER.  SHOULD ANY PART OF THE JASPER SOFTWARE PROVE DEFECTIVE * IN ANY RESPECT, THE USER (AND NOT THE INITIAL DEVELOPERS, THE UNIVERSITY * OF BRITISH COLUMBIA, IMAGE POWER, INC., MICHAEL DAVID ADAMS, OR ANY * OTHER CONTRIBUTOR) SHALL ASSUME THE COST OF ANY NECESSARY SERVICING, * REPAIR OR CORRECTION.  UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY, * WHETHER TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL THE * INITIAL DEVELOPER, THE UNIVERSITY OF BRITISH COLUMBIA, IMAGE POWER, INC., * MICHAEL DAVID ADAMS, ANY OTHER CONTRIBUTOR, OR ANY DISTRIBUTOR OF THE * JASPER SOFTWARE, OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO * THE USER OR ANY OTHER PERSON FOR ANY INDIRECT, SPECIAL, INCIDENTAL, OR * CONSEQUENTIAL DAMAGES OF ANY CHARACTER INCLUDING, WITHOUT LIMITATION, * DAMAGES FOR LOSS OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR * MALFUNCTION, OR ANY AND ALL OTHER COMMERCIAL DAMAGES OR LOSSES, EVEN IF * SUCH PARTY HAD BEEN INFORMED, OR OUGHT TO HAVE KNOWN, OF THE POSSIBILITY * OF SUCH DAMAGES.  THE JASPER SOFTWARE AND UNDERLYING TECHNOLOGY ARE NOT * FAULT-TOLERANT AND ARE NOT DESIGNED, MANUFACTURED OR INTENDED FOR USE OR * RESALE AS ON-LINE CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING * FAIL-SAFE PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES, * AIRCRAFT NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT * LIFE SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE * JASPER SOFTWARE OR UNDERLYING TECHNOLOGY OR PRODUCT COULD LEAD DIRECTLY * TO DEATH, PERSONAL INJURY, OR SEVERE PHYSICAL OR ENVIRONMENTAL DAMAGE * ("HIGH RISK ACTIVITIES").  LICENSOR SPECIFICALLY DISCLAIMS ANY EXPRESS * OR IMPLIED WARRANTY OF FITNESS FOR HIGH RISK ACTIVITIES.  USER WILL NOT * KNOWINGLY USE, DISTRIBUTE OR RESELL THE JASPER SOFTWARE OR UNDERLYING * TECHNOLOGY OR PRODUCTS FOR HIGH RISK ACTIVITIES AND WILL ENSURE THAT ITS * CUSTOMERS AND END-USERS OF ITS PRODUCTS ARE PROVIDED WITH A COPY OF THE * NOTICE SPECIFIED IN THIS SECTION. *  * __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;}

⌨️ 快捷键说明

复制代码 Ctrl + C
搜索代码 Ctrl + F
全屏模式 F11
切换主题 Ctrl + Shift + D
显示快捷键 ?
增大字号 Ctrl + =
减小字号 Ctrl + -