/* * 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 <inttypes.h> #include <limits.h> #include <stdio.h> #include <string.h> #include "libavutil/dict.h" #include "libavutil/error.h" #include "libavutil/log.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); switch(header->bitpix) { case 8: case 16: case 32: case -32: case 64: case -64: break; default: av_log(avcl, AV_LOG_ERROR, "invalid value of BITPIX %d\n", header->bitpix); \ return AVERROR_INVALIDDATA; } 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) { if (d <= 0) return AVERROR_INVALIDDATA; 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) { if (t < 0 || t > INT_MAX) return AVERROR_INVALIDDATA; header->gcount = t; } else if (!strcmp(keyword, "PCOUNT") && sscanf(value, "%"SCNd64"", &t) == 1) { if (t < 0 || t > INT_MAX) return AVERROR_INVALIDDATA; header->pcount = t; } dict_set_if_not_null(metadata, keyword, value); break; } return 0; }