/*
* FITS implementation of common functions
* Copyright (c) 2017 Paras Chadha
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "libavutil/dict.h"
#include "fits.h"
int avpriv_fits_header_init(FITSHeader *header, FITSHeaderState state)
{
header->state = state;
header->naxis_index = 0;
header->blank_found = 0;
header->pcount = 0;
header->gcount = 1;
header->groups = 0;
header->rgb = 0;
header->image_extension = 0;
header->bscale = 1.0;
header->bzero = 0;
header->data_min_found = 0;
header->data_max_found = 0;
return 0;
}
static int dict_set_if_not_null(AVDictionary ***metadata, char *keyword, char *value)
{
if (metadata)
av_dict_set(*metadata, keyword, value, 0);
return 0;
}
/**
* Extract keyword and value from a header line (80 bytes) and store them in keyword and value strings respectively
* @param ptr8 pointer to the data
* @param keyword pointer to the char array in which keyword is to be stored
* @param value pointer to the char array in which value is to be stored
* @return 0 if calculated successfully otherwise AVERROR_INVALIDDATA
*/
static int read_keyword_value(const uint8_t *ptr8, char *keyword, char *value)
{
int i;
for (i = 0; i < 8 && ptr8[i] != ' '; i++) {
keyword[i] = ptr8[i];
}
keyword[i] = '\0';
if (ptr8[8] == '=') {
i = 10;
while (i < 80 && ptr8[i] == ' ') {
i++;
}
if (i < 80) {
*value++ = ptr8[i];
i++;
if (ptr8[i-1] == '\'') {
for (; i < 80 && ptr8[i] != '\''; i++) {
*value++ = ptr8[i];
}
*value++ = '\'';
} else if (ptr8[i-1] == '(') {
for (; i < 80 && ptr8[i] != ')'; i++) {
*value++ = ptr8[i];
}
*value++ = ')';
} else {
for (; i < 80 && ptr8[i] != ' ' && ptr8[i] != '/'; i++) {
*value++ = ptr8[i];
}
}
}
}
*value = '\0';
return 0;
}
#define CHECK_KEYWORD(key) \
if (strcmp(keyword, key)) { \
av_log(avcl, AV_LOG_ERROR, "expected %s keyword, found %s = %s\n", key, keyword, value); \
return AVERROR_INVALIDDATA; \
}
#define CHECK_VALUE(key, val) \
if (sscanf(value, "%d", &header->val) != 1) { \
av_log(avcl, AV_LOG_ERROR, "invalid value of %s keyword, %s = %s\n", key, keyword, value); \
return AVERROR_INVALIDDATA; \
}
int avpriv_fits_header_parse_line(void *avcl, FITSHeader *header, const uint8_t line[80], AVDictionary ***metadata)
{
int dim_no, ret;
int64_t t;
double d;
char keyword[10], value[72], c;
read_keyword_value(line, keyword, value);
switch (header->state) {
case STATE_SIMPLE:
CHECK_KEYWORD("SIMPLE");
if (value[0] == 'F') {
av_log(avcl, AV_LOG_WARNING, "not a standard FITS file\n");
} else if (value[0] != 'T') {
av_log(avcl, AV_LOG_ERROR, "invalid value of SIMPLE keyword, SIMPLE = %c\n", value[0]);
return AVERROR_INVALIDDATA;
}
header->state = STATE_BITPIX;
break;
case STATE_XTENSION:
CHECK_KEYWORD("XTENSION");
if (!strcmp(value, "'IMAGE '")) {
header->image_extension = 1;
}
header->state = STATE_BITPIX;
break;
case STATE_BITPIX:
CHECK_KEYWORD("BITPIX");
CHECK_VALUE("BITPIX", bitpix);
dict_set_if_not_null(metadata, keyword, value);
header->state = STATE_NAXIS;
break;
case STATE_NAXIS:
CHECK_KEYWORD("NAXIS");
CHECK_VALUE("NAXIS", naxis);
dict_set_if_not_null(metadata, keyword, value);
if (header->naxis) {
header->state = STATE_NAXIS_N;
} else {
header->state = STATE_REST;
}
break;
case STATE_NAXIS_N:
ret = sscanf(keyword, "NAXIS%d", &dim_no);
if (ret != 1 || dim_no != header->naxis_index + 1) {
av_log(avcl, AV_LOG_ERROR, "expected NAXIS%d keyword, found %s = %s\n", header->naxis_index + 1, keyword, value);
return AVERROR_INVALIDDATA;
}
if (sscanf(value, "%d", &header->naxisn[header->naxis_index]) != 1) {
av_log(avcl, AV_LOG_ERROR, "invalid value of NAXIS%d keyword, %s = %s\n", header->naxis_index + 1, keyword, value);
return AVERROR_INVALIDDATA;
}
dict_set_if_not_null(metadata, keyword, value);
header->naxis_index++;
if (header->naxis_index == header->naxis) {
header->state = STATE_REST;
}
break;
case STATE_REST:
if (!strcmp(keyword, "BLANK") && sscanf(value, "%"SCNd64"", &t) == 1) {
header->blank = t;
header->blank_found = 1;
} else if (!strcmp(keyword, "BSCALE") && sscanf(value, "%lf", &d) == 1) {
header->bscale = d;
} else if (!strcmp(keyword, "BZERO") && sscanf(value, "%lf", &d) == 1) {
header->bzero = d;
} else if (!strcmp(keyword, "CTYPE3") && !strncmp(value, "'RGB", 4)) {
header->rgb = 1;
} else if (!strcmp(keyword, "DATAMAX") && sscanf(value, "%lf", &d) == 1) {
header->data_max_found = 1;
header->data_max = d;
} else if (!strcmp(keyword, "DATAMIN") && sscanf(value, "%lf", &d) == 1) {
header->data_min_found = 1;
header->data_min = d;
} else if (!strcmp(keyword, "END")) {
return 1;
} else if (!strcmp(keyword, "GROUPS") && sscanf(value, "%c", &c) == 1) {
header->groups = (c == 'T');
} else if (!strcmp(keyword, "GCOUNT") && sscanf(value, "%"SCNd64"", &t) == 1) {
header->gcount = t;
} else if (!strcmp(keyword, "PCOUNT") && sscanf(value, "%"SCNd64"", &t) == 1) {
header->pcount = t;
}
dict_set_if_not_null(metadata, keyword, value);
break;
}
return 0;
}