/***************************************************************
* Ceos_init_stVec:
* Reads state vectors from given CEOS file, writing them in the
* appropriate format to SAR parameters structure.*/
void ceos_init_stVec(const char *fName, ceos_description *ceos,
meta_parameters *meta)
{
struct pos_data_rec ppdr;
/*Fetch platform position data record.*/
get_ppdr(fName,&ppdr);
// Read the state vectors from the leader data file, adjust coordinate system, etc.
// and write them to the SAR parameters structures
ceos_read_stVecs(fName, ceos, meta);
// Propagate three state vectors for regular frames
if (ceos->processor != PREC && ceos->processor != unknownProcessor) {
int vector_count=3;
double data_int = meta->sar->original_line_count / 2
* fabs(meta->sar->azimuth_time_per_pixel);
meta->state_vectors->vecs[0].time = get_timeDelta(ceos, &ppdr, meta);
if (ceos->processor != PREC && data_int < 360.0) {
while (fabs(data_int) > 15.0) {
data_int /= 2;
vector_count = vector_count*2-1;
}
// propagate three state vectors: start, center, end
propagate_state(meta, vector_count, data_int);
}
}
}
/**************************************************************************
* atct_init_from_leader:
* calculates alpha1, alpha2, and alpha3, which are some sort of coordinate
* rotation amounts, in degrees. This creates a latitude/longitude-style
* coordinate system centered under the satellite at the start of imaging.
* Rather than using a passed-in state vector, the initial state vector is
* read from the leader file.
*/
void atct_init_from_leader(const char *leaderName, meta_projection *proj)
{
struct dataset_sum_rec *dssr = NULL;
meta_parameters *meta = raw_init();
stateVector st_start;
ceos_description *ceos =
get_ceos_description_ext(leaderName, REPORT_LEVEL_NONE, FALSE);
// Azimuth time per pixel need to be known for state vector propagation
dssr = &ceos->dssr;
ceos_init_sar_general(ceos, leaderName, meta, TRUE);
ceos_read_stVecs(leaderName, ceos, meta);
st_start = meta_get_stVec(meta, 0.0);
fixed2gei(&st_start,0.0);/* Remove earth's spin JPL's AT/CT projection requires this */
atct_init(proj, st_start);
meta_free(meta);
}
/***************************************************************
* Ceos_init_stVec:
* Reads state vectors from given CEOS file, writing them in the
* appropriate format to SAR parameters structure.*/
void ceos_init_stVec(const char *fName, ceos_description *ceos,
meta_parameters *meta)
{
struct pos_data_rec ppdr;
/*Fetch platform position data record.*/
get_ppdr(fName,&ppdr);
// Read the state vectors from the leader data file, adjust coordinate system, etc.
// and write them to the SAR parameters structures
ceos_read_stVecs(fName, ceos, meta);
// For ALOS Palsar orbits only
// Don't propagate but select nine state vectors around the center for the
// higher order interpolation scheme
if (ceos->processor == ALOS_PROC) {
// Determine closest state vector
int ii, min;
double diff = 99999999;
for (ii=0; ii<meta->state_vectors->vector_count; ii++) {
if (fabs(meta->state_vectors->vecs[ii].time) < diff) {
diff = fabs(meta->state_vectors->vecs[ii].time);
min = ii;
}
}
// Populate a new state vector
ymd_date img_ymd;
julian_date img_jd;
hms_time img_time;
img_jd.year = meta->state_vectors->year;
img_jd.jd = meta->state_vectors->julDay;
date_sec2hms(meta->state_vectors->second,&img_time);
date_jd2ymd(&img_jd, &img_ymd);
add_time((min-4)*60, &img_ymd, &img_time);
date_ymd2jd(&img_ymd, &img_jd);
meta_state_vectors *new_st = meta_state_vectors_init(9);
new_st->year = img_jd.year;
new_st->julDay = img_jd.jd;
new_st->second = date_hms2sec(&img_time);
for (ii=0; ii<9; ii++)
new_st->vecs[ii] = meta->state_vectors->vecs[ii+min-4];
FREE(meta->state_vectors);
meta->state_vectors = new_st;
// Time shift should definitely set in the code that is calling this function
// meta->sar->time_shift = 0.0;
}
// Propagate three state vectors for regular frames
else if (ceos->processor != PREC && ceos->processor != unknownProcessor) {
int vector_count=3;
double data_int = meta->sar->original_line_count / 2
* fabs(meta->sar->azimuth_time_per_pixel);
meta->state_vectors->vecs[0].time = get_timeDelta(ceos, &ppdr, meta);
if (ceos->processor != PREC && data_int < 360.0) {
while (fabs(data_int) > 15.0) {
data_int /= 2;
vector_count = vector_count*2-1;
}
// propagate three state vectors: start, center, end
propagate_state(meta, vector_count, data_int);
}
}
}
