1 /*
2 Copyright (c) 2005-2023 Intel Corporation
3
4 Licensed under the Apache License, Version 2.0 (the "License");
5 you may not use this file except in compliance with the License.
6 You may obtain a copy of the License at
7
8 http://www.apache.org/licenses/LICENSE-2.0
9
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
15 */
16
17 /*
18 The original source for this example is
19 Copyright (c) 1994-2008 John E. Stone
20 All rights reserved.
21
22 Redistribution and use in source and binary forms, with or without
23 modification, are permitted provided that the following conditions
24 are met:
25 1. Redistributions of source code must retain the above copyright
26 notice, this list of conditions and the following disclaimer.
27 2. Redistributions in binary form must reproduce the above copyright
28 notice, this list of conditions and the following disclaimer in the
29 documentation and/or other materials provided with the distribution.
30 3. The name of the author may not be used to endorse or promote products
31 derived from this software without specific prior written permission.
32
33 THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
34 OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
35 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
36 ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
37 DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
38 DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
39 OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
40 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
41 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
42 OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
43 SUCH DAMAGE.
44 */
45
46 /*
47 * jpeg.cpp - This file deals with JPEG format image files (reading/writing)
48 */
49
50 /*
51 * This code requires support from the Independent JPEG Group's libjpeg.
52 * For our purposes, we're interested only in the 3 byte per pixel 24 bit
53 * RGB output. Probably won't implement any decent checking at this point.
54 */
55
56 #include <cstdio>
57
58 #include "machine.hpp"
59 #include "types.hpp"
60 #include "util.hpp"
61 #include "imageio.hpp" /* error codes etc */
62 #include "jpeg.hpp" /* the protos for this file */
63
64 #if !defined(USEJPEG)
65
readjpeg(char * name,int * xres,int * yres,unsigned char ** imgdata)66 int readjpeg(char *name, int *xres, int *yres, unsigned char **imgdata) {
67 return IMAGEUNSUP;
68 }
69
70 #else
71
72 #include "jpeglib.hpp" /* the IJG jpeg library headers */
73
readjpeg(char * name,int * xres,int * yres,unsigned char ** imgdata)74 int readjpeg(char *name, int *xres, int *yres, unsigned char **imgdata) {
75 FILE *ifp;
76 struct jpeg_decompress_struct cinfo; /* JPEG decompression struct */
77 struct jpeg_error_mgr jerr; /* JPEG Error handler */
78 JSAMPROW row_pointer[1]; /* output row buffer */
79 int row_stride; /* physical row width in output buf */
80
81 /* open input file before doing any JPEG decompression setup */
82 if ((ifp = fopen(name, "rb")) == nullptr)
83 return IMAGEBADFILE; /* Could not open image, return error */
84
85 /*
86 * Note: The Independent JPEG Group's library does not have a way
87 * of returning errors without the use of setjmp/longjmp.
88 * This is a problem in multi-threaded environment, since setjmp
89 * and longjmp are declared thread-unsafe by many vendors currently.
90 * For now, JPEG decompression errors will result in the "default"
91 * error handling provided by the JPEG library, which is an error
92 * message and a fatal call to exit(). I'll have to work around this
93 * or find a reasonably thread-safe way of doing setjmp/longjmp..
94 */
95
96 cinfo.err = jpeg_std_error(&jerr); /* Set JPEG error handler to default */
97
98 jpeg_create_decompress(&cinfo); /* Create decompression context */
99 jpeg_stdio_src(&cinfo, ifp); /* Set input mechanism to stdio type */
100 jpeg_read_header(&cinfo, TRUE); /* Read the JPEG header for info */
101 jpeg_start_decompress(&cinfo); /* Prepare for actual decompression */
102
103 *xres = cinfo.output_width; /* set returned image width */
104 *yres = cinfo.output_height; /* set returned image height */
105
106 /* Calculate the size of a row in the image */
107 row_stride = cinfo.output_width * cinfo.output_components;
108
109 /* Allocate the image buffer which will be returned to the ray tracer */
110 *imgdata = (unsigned char *)malloc(row_stride * cinfo.output_height);
111
112 /* decompress the JPEG, one scanline at a time into the buffer */
113 while (cinfo.output_scanline < cinfo.output_height) {
114 row_pointer[0] = &((*imgdata)[(cinfo.output_scanline) * row_stride]);
115 jpeg_read_scanlines(&cinfo, row_pointer, 1);
116 }
117
118 jpeg_finish_decompress(&cinfo); /* Tell the JPEG library to cleanup */
119 jpeg_destroy_decompress(&cinfo); /* Destroy JPEG decompression context */
120
121 fclose(ifp); /* Close the input file */
122
123 return IMAGENOERR; /* No fatal errors */
124 }
125
126 #endif
127