1 /*
2 * FITS implementation of common functions
3 * Copyright (c) 2017 Paras Chadha
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "avcodec.h"
23 #include "libavutil/dict.h"
24 #include "fits.h"
25
avpriv_fits_header_init(FITSHeader * header,FITSHeaderState state)26 int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
27 {
28 header->state = state;
29 header->naxis_index = 0;
30 header->blank_found = 0;
31 header->pcount = 0;
32 header->gcount = 1;
33 header->groups = 0;
34 header->rgb = 0;
35 header->image_extension = 0;
36 header->bscale = 1.0;
37 header->bzero = 0;
38 header->data_min_found = 0;
39 header->data_max_found = 0;
40 return 0;
41 }
42
dict_set_if_not_null(AVDictionary *** metadata,char * keyword,char * value)43 static int dict_set_if_not_null(AVDictionary ***metadata, char *keyword, char *value)
44 {
45 if (metadata)
46 av_dict_set(*metadata, keyword, value, 0);
47 return 0;
48 }
49
50 /**
51 * Extract keyword and value from a header line (80 bytes) and store them in keyword and value strings respectively
52 * @param ptr8 pointer to the data
53 * @param keyword pointer to the char array in which keyword is to be stored
54 * @param value pointer to the char array in which value is to be stored
55 * @return 0 if calculated successfully otherwise AVERROR_INVALIDDATA
56 */
read_keyword_value(const uint8_t * ptr8,char * keyword,char * value)57 static int read_keyword_value(const uint8_t *ptr8, char *keyword, char *value)
58 {
59 int i;
60
61 for (i = 0; i < 8 && ptr8[i] != ' '; i++) {
62 keyword[i] = ptr8[i];
63 }
64 keyword[i] = '\0';
65
66 if (ptr8[8] == '=') {
67 i = 10;
68 while (i < 80 && ptr8[i] == ' ') {
69 i++;
70 }
71
72 if (i < 80) {
73 *value++ = ptr8[i];
74 i++;
75 if (ptr8[i-1] == '\'') {
76 for (; i < 80 && ptr8[i] != '\''; i++) {
77 *value++ = ptr8[i];
78 }
79 *value++ = '\'';
80 } else if (ptr8[i-1] == '(') {
81 for (; i < 80 && ptr8[i] != ')'; i++) {
82 *value++ = ptr8[i];
83 }
84 *value++ = ')';
85 } else {
86 for (; i < 80 && ptr8[i] != ' ' && ptr8[i] != '/'; i++) {
87 *value++ = ptr8[i];
88 }
89 }
90 }
91 }
92 *value = '\0';
93 return 0;
94 }
95
96 #define CHECK_KEYWORD(key) \
97 if (strcmp(keyword, key)) { \
98 av_log(avcl, AV_LOG_ERROR, "expected %s keyword, found %s = %s\n", key, keyword, value); \
99 return AVERROR_INVALIDDATA; \
100 }
101
102 #define CHECK_VALUE(key, val) \
103 if (sscanf(value, "%d", &header->val) != 1) { \
104 av_log(avcl, AV_LOG_ERROR, "invalid value of %s keyword, %s = %s\n", key, keyword, value); \
105 return AVERROR_INVALIDDATA; \
106 }
107
avpriv_fits_header_parse_line(void * avcl,FITSHeader * header,const uint8_t line[80],AVDictionary *** metadata)108 int avpriv_fits_header_parse_line(void *avcl, FITSHeader *header, const uint8_t line[80], AVDictionary ***metadata)
109 {
110 int dim_no, ret;
111 int64_t t;
112 double d;
113 char keyword[10], value[72], c;
114
115 read_keyword_value(line, keyword, value);
116 switch (header->state) {
117 case STATE_SIMPLE:
118 CHECK_KEYWORD("SIMPLE");
119
120 if (value[0] == 'F') {
121 av_log(avcl, AV_LOG_WARNING, "not a standard FITS file\n");
122 } else if (value[0] != 'T') {
123 av_log(avcl, AV_LOG_ERROR, "invalid value of SIMPLE keyword, SIMPLE = %c\n", value[0]);
124 return AVERROR_INVALIDDATA;
125 }
126
127 header->state = STATE_BITPIX;
128 break;
129 case STATE_XTENSION:
130 CHECK_KEYWORD("XTENSION");
131
132 if (!strcmp(value, "'IMAGE '")) {
133 header->image_extension = 1;
134 }
135
136 header->state = STATE_BITPIX;
137 break;
138 case STATE_BITPIX:
139 CHECK_KEYWORD("BITPIX");
140 CHECK_VALUE("BITPIX", bitpix);
141
142 switch(header->bitpix) {
143 case 8:
144 case 16:
145 case 32: case -32:
146 case 64: case -64: break;
147 default:
148 av_log(avcl, AV_LOG_ERROR, "invalid value of BITPIX %d\n", header->bitpix); \
149 return AVERROR_INVALIDDATA;
150 }
151
152 dict_set_if_not_null(metadata, keyword, value);
153
154 header->state = STATE_NAXIS;
155 break;
156 case STATE_NAXIS:
157 CHECK_KEYWORD("NAXIS");
158 CHECK_VALUE("NAXIS", naxis);
159 dict_set_if_not_null(metadata, keyword, value);
160
161 if (header->naxis) {
162 header->state = STATE_NAXIS_N;
163 } else {
164 header->state = STATE_REST;
165 }
166 break;
167 case STATE_NAXIS_N:
168 ret = sscanf(keyword, "NAXIS%d", &dim_no);
169 if (ret != 1 || dim_no != header->naxis_index + 1) {
170 av_log(avcl, AV_LOG_ERROR, "expected NAXIS%d keyword, found %s = %s\n", header->naxis_index + 1, keyword, value);
171 return AVERROR_INVALIDDATA;
172 }
173
174 if (sscanf(value, "%d", &header->naxisn[header->naxis_index]) != 1) {
175 av_log(avcl, AV_LOG_ERROR, "invalid value of NAXIS%d keyword, %s = %s\n", header->naxis_index + 1, keyword, value);
176 return AVERROR_INVALIDDATA;
177 }
178
179 dict_set_if_not_null(metadata, keyword, value);
180 header->naxis_index++;
181 if (header->naxis_index == header->naxis) {
182 header->state = STATE_REST;
183 }
184 break;
185 case STATE_REST:
186 if (!strcmp(keyword, "BLANK") && sscanf(value, "%"SCNd64"", &t) == 1) {
187 header->blank = t;
188 header->blank_found = 1;
189 } else if (!strcmp(keyword, "BSCALE") && sscanf(value, "%lf", &d) == 1) {
190 if (d <= 0)
191 return AVERROR_INVALIDDATA;
192 header->bscale = d;
193 } else if (!strcmp(keyword, "BZERO") && sscanf(value, "%lf", &d) == 1) {
194 header->bzero = d;
195 } else if (!strcmp(keyword, "CTYPE3") && !strncmp(value, "'RGB", 4)) {
196 header->rgb = 1;
197 } else if (!strcmp(keyword, "DATAMAX") && sscanf(value, "%lf", &d) == 1) {
198 header->data_max_found = 1;
199 header->data_max = d;
200 } else if (!strcmp(keyword, "DATAMIN") && sscanf(value, "%lf", &d) == 1) {
201 header->data_min_found = 1;
202 header->data_min = d;
203 } else if (!strcmp(keyword, "END")) {
204 return 1;
205 } else if (!strcmp(keyword, "GROUPS") && sscanf(value, "%c", &c) == 1) {
206 header->groups = (c == 'T');
207 } else if (!strcmp(keyword, "GCOUNT") && sscanf(value, "%"SCNd64"", &t) == 1) {
208 if (t < 0 || t > INT_MAX)
209 return AVERROR_INVALIDDATA;
210 header->gcount = t;
211 } else if (!strcmp(keyword, "PCOUNT") && sscanf(value, "%"SCNd64"", &t) == 1) {
212 if (t < 0 || t > INT_MAX)
213 return AVERROR_INVALIDDATA;
214 header->pcount = t;
215 }
216 dict_set_if_not_null(metadata, keyword, value);
217 break;
218 }
219 return 0;
220 }
221