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sattools/pstrack.c

689 lines
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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <wcslib/cel.h>
#include <cpgplot.h>
#include "qfits.h"
#include "sgdp4h.h"
#define LIM 80
#define NMAX 256
#define D2R M_PI/180.0
#define R2D 180.0/M_PI
#define XKMPER 6378.135 // Earth radius in km
#define XKMPAU 149597879.691 // AU in km
#define FLAT (1.0/298.257)
#define STDMAG 6.0
#define MMAX 10
long Isat=0;
long Isatsel=0;
extern double SGDP4_jd0;
struct map {
double lat,lng;
float alt;
char observer[32];
int site_id;
} m;
struct image {
char filename[64];
int naxis1,naxis2,naxis3,nframes;
float *zavg,*zstd,*zmax,*znum,*zd;
double ra0,de0;
float x0,y0;
float a[3],b[3],xrms,yrms;
double mjd;
float *dt,exptime;
char nfd[32];
int cospar;
};
struct sat {
long Isat;
char state[10];
float mag;
double jd;
double dx,dy,dz;
double x,y,z,vx,vy,vz;
double rsun,rearth;
double psun,pearth,p,phase;
double r,v,ra,de;
double azi,alt;
double rx,ry;
};
struct track {
float x0,y0,x1,y1;
};
struct image read_fits(char *filename);
struct sat apparent_position(double mjd);
double modulo(double,double);
void obspos_xyz(double,xyz_t *,xyz_t *);
void sunpos_xyz(double,xyz_t *);
double gmst(double);
double dgmst(double);
void forward(double ra0,double de0,double ra,double de,double *x,double *y);
void reverse(double ra0,double de0,double x,double y,double *ra,double *de);
// Get observing site
void get_site(int site_id)
{
int i=0;
char line[LIM];
FILE *file;
int id;
double lat,lng;
float alt;
char abbrev[3],observer[64],filename[LIM],*env;
env=getenv("ST_DATADIR");
sprintf(filename,"%s/data/sites.txt",env);
file=fopen(filename,"r");
if (file==NULL) {
printf("File with site information not found!\n");
return;
}
while (fgets(line,LIM,file)!=NULL) {
// Skip
if (strstr(line,"#")!=NULL)
continue;
// Strip newline
line[strlen(line)-1]='\0';
// Read data
sscanf(line,"%4d %2s %lf %lf %f",
&id,abbrev,&lat,&lng,&alt);
strcpy(observer,line+38);
// Change to km
alt/=1000.0;
if (id==site_id) {
m.lat=lat;
m.lng=lng;
m.alt=alt;
m.site_id=id;
strcpy(m.observer,observer);
}
}
fclose(file);
return;
}
// Precess a celestial position
void precess(double mjd0,double ra0,double de0,double mjd,double *ra,double *de)
{
double t0,t;
double zeta,z,theta;
double a,b,c;
// Angles in radians
ra0*=D2R;
de0*=D2R;
// Time in centuries
t0=(mjd0-51544.5)/36525.0;
t=(mjd-mjd0)/36525.0;
// Precession angles
zeta=(2306.2181+1.39656*t0-0.000139*t0*t0)*t;
zeta+=(0.30188-0.000344*t0)*t*t+0.017998*t*t*t;
zeta*=D2R/3600.0;
z=(2306.2181+1.39656*t0-0.000139*t0*t0)*t;
z+=(1.09468+0.000066*t0)*t*t+0.018203*t*t*t;
z*=D2R/3600.0;
theta=(2004.3109-0.85330*t0-0.000217*t0*t0)*t;
theta+=-(0.42665+0.000217*t0)*t*t-0.041833*t*t*t;
theta*=D2R/3600.0;
a=cos(de0)*sin(ra0+zeta);
b=cos(theta)*cos(de0)*cos(ra0+zeta)-sin(theta)*sin(de0);
c=sin(theta)*cos(de0)*cos(ra0+zeta)+cos(theta)*sin(de0);
*ra=(atan2(a,b)+z)*R2D;
*de=asin(c)*R2D;
if (*ra<360.0)
*ra+=360.0;
if (*ra>360.0)
*ra-=360.0;
return;
}
orbit_t find_tle(char *tlefile,struct image img,int satno)
{
int i;
orbit_t orb;
struct sat s;
int imode,flag,textflag;
FILE *fp=NULL;
xyz_t satpos,obspos,satvel,sunpos;
double mjd,jd,dx,dy,dz;
double rx,ry,ra,de,azi,alt,r,t,d;
float x[MMAX],y[MMAX],x0,y0;
char norad[7],satname[30];
float isch;
float rsun,rearth,psun,pearth,p;
char filename[128];
double mnan,mnanmin,rmin;
// Open TLE file
fp=fopen(tlefile,"rb");
if (fp==NULL)
fatal_error("File open failed for reading %s\n",tlefile);
// Read TLEs
if (satno!=0) {
read_twoline(fp,satno,&orb);
fclose(fp);
return orb;
}
read_twoline(fp,0,&orb);
fclose(fp);
for (i=0,mnan=0.0;mnan<360.0;mnan+=0.01,i++) {
orb.mnan=mnan*D2R;
Isat=orb.satno;
imode=init_sgdp4(&orb);
mjd=img.mjd+0.5*img.exptime/86400.0;
// Compute apparent position
s=apparent_position(mjd);
r=acos(sin(img.de0*D2R)*sin(s.de*D2R)+cos(img.de0*D2R)*cos(s.de*D2R)*cos((img.ra0-s.ra)*D2R))*R2D;
if (r<10.0) {
forward(img.ra0,img.de0,s.ra,s.de,&s.rx,&s.ry);
r=sqrt(s.rx*s.rx+s.ry*s.ry)/3600.0;
}
if (i==0 || r<rmin) {
mnanmin=mnan;
rmin=r;
}
}
orb.mnan=mnanmin*D2R;
return orb;
}
struct track plot_satellite(orbit_t orb,struct image img)
{
int i;
struct sat s;
int imode,flag,textflag;
FILE *fp=NULL,*file;;
xyz_t satpos,obspos,satvel,sunpos;
double mjd,jd,dx,dy,dz;
double rx,ry,ra,de,azi,alt,r,t,d;
float x[MMAX],y[MMAX];
char norad[7],satname[30];
float isch;
float rsun,rearth,psun,pearth,p;
char filename[128];
struct track trk;
// Image determinant
d=img.a[1]*img.b[2]-img.a[2]*img.b[1];
// Read TLEs
Isat=orb.satno;
imode=init_sgdp4(&orb);
if (imode==SGDP4_ERROR)
return trk;
for (flag=0,textflag=0,i=0;i<MMAX;i++) {
t=img.exptime*(float) i/(float) (MMAX-1);
mjd=img.mjd+t/86400.0;
// Compute apparent position
s=apparent_position(mjd);
// Convert to rx,ry
r=acos(sin(img.de0*D2R)*sin(s.de*D2R)+cos(img.de0*D2R)*cos(s.de*D2R)*cos((img.ra0-s.ra)*D2R))*R2D;
if (r<90.0)
forward(img.ra0,img.de0,s.ra,s.de,&s.rx,&s.ry);
else
return trk;
// Convert image position
dx=s.rx-img.a[0];
dy=s.ry-img.b[0];
x[i]=(img.b[2]*dx-img.a[2]*dy)/d+img.x0;
y[i]=(img.a[1]*dy-img.b[1]*dx)/d+img.y0;
}
trk.x0=x[0];
trk.y0=y[0];
trk.x1=x[MMAX-1];
trk.y1=y[MMAX-1];
return trk;
}
void track_image(struct image *img,struct track trk)
{
FILE *file;
char line[LIM],filename[LIM];
int flag=0,satno;
float x0,y0,x1,y1,texp;
int i,j,k,l,k0;
int di,dj;
float *z;
int *wt;
float dxdn,dydn,dx,dy;
dxdn=(trk.x1-trk.x0)/(float) img->nframes;
dydn=(trk.y1-trk.y0)/(float) img->nframes;
// Allocate
z=(float *) malloc(sizeof(float)*img->naxis1*img->naxis2);
wt=(int *) malloc(sizeof(int)*img->naxis1*img->naxis2);
// Set to zero
for (i=0;i<img->naxis1*img->naxis2;i++) {
z[i]=0.0;
wt[i]=0;
}
// Loop over frames
for (l=0;l<img->nframes;l++) {
// Offset
dx=dxdn*(l-img->nframes/2);
dy=dydn*(l-img->nframes/2);
// Integer offset
di=(int) floor(dx+0.5);
dj=(int) floor(dy+0.5);
// Set
for (i=0;i<img->naxis1;i++) {
for (j=0;j<img->naxis2;j++) {
k=i+img->naxis1*j;
k0=i+di+img->naxis1*(j+dj);
if (i+di>0 && i+di<img->naxis1 && j+dj>0 && j+dj<img->naxis2) {
wt[k]+=1;
if (img->znum[k0]==l)
z[k]+=img->zmax[k0];
// else
// z[k]+=img->zavg[k0];
}
}
}
}
// Scale
for (i=0;i<img->naxis1*img->naxis2;i++) {
if (wt[i]>0)
img->zd[i]=z[i]/(float) wt[i];
else
img->zd[i]=z[i];
}
img->naxis3=5;
free(z);
free(wt);
return;
}
int main(int argc,char *argv[])
{
int i;
struct image img;
float zmin,zmax,zavg,zstd;
float tr[]={-0.5,1.0,0.0,-0.5,0.0,1.0};
float heat_l[] = {0.0, 0.2, 0.4, 0.6, 1.0};
float heat_r[] = {0.0, 0.5, 1.0, 1.0, 1.0};
float heat_g[] = {0.0, 0.0, 0.5, 1.0, 1.0};
float heat_b[] = {0.0, 0.0, 0.0, 0.3, 1.0};
char text[128];
orbit_t orb;
float x0,y0,x1,y1;
struct track trk;
FILE *file;
char filename[128];
int satno=0;
char *env;
// Read image
img=read_fits(argv[1]);
// Set site
get_site(img.cospar);
if (argc==5)
satno=atoi(argv[4]);
// Find closest orbit
orb=find_tle(argv[2],img,satno);
trk=plot_satellite(orb,img);
track_image(&img,trk);
for (i=0,zavg=0.0;i<img.naxis1*img.naxis2;i++)
zavg+=img.zd[i];
zavg/=(float) img.naxis1*img.naxis2;
for (i=0,zstd=0.0;i<img.naxis1*img.naxis2;i++)
zstd+=pow(img.zd[i]-zavg,2);
zstd=sqrt(zstd/(float) (img.naxis1*img.naxis2));
zmin=zavg-2*zstd;
zmax=zavg+6*zstd;
if (argc==4)
cpgopen(argv[3]);
else
cpgopen("/xs");
cpgpap(0.,1.0);
cpgsvp(0.1,0.95,0.1,0.8);
cpgsch(0.8);
sprintf(text,"UT Date: %.23s COSPAR ID: %04d",img.nfd+1,img.cospar);
cpgmtxt("T",6.0,0.0,0.0,text);
sprintf(text,"R.A.: %10.5f (%4.1f'') Decl.: %10.5f (%4.1f'')",img.ra0,img.xrms,img.de0,img.yrms);
cpgmtxt("T",4.8,0.0,0.0,text);
sprintf(text,"FoV: %.2f\\(2218)x%.2f\\(2218) Scale: %.2f''x%.2f'' pix\\u-1\\d",img.naxis1*sqrt(img.a[1]*img.a[1]+img.b[1]*img.b[1])/3600.0,img.naxis2*sqrt(img.a[2]*img.a[2]+img.b[2]*img.b[2])/3600.0,sqrt(img.a[1]*img.a[1]+img.b[1]*img.b[1]),sqrt(img.a[2]*img.a[2]+img.b[2]*img.b[2]));
cpgmtxt("T",3.6,0.0,0.0,text);
sprintf(text,"Stat: %5.1f+-%.1f (%.1f-%.1f)",zavg,zstd,zmin,zmax);
cpgmtxt("T",2.4,0.0,0.0,text);
cpgsch(1.0);
cpgwnad(0.0,img.naxis1,0.0,img.naxis2);
cpglab("x (pix)","y (pix)"," ");
cpgctab (heat_l,heat_r,heat_g,heat_b,5,1.0,0.5);
cpgimag(img.zd,img.naxis1,img.naxis2,1,img.naxis1,1,img.naxis2,zmin,zmax,tr);
cpgbox("BCTSNI",0.,0,"BCTSNI",0.,0);
cpgstbg(1);
cpgsci(4);
cpgpt1(trk.x0,trk.y0,17);
cpgpt1(trk.x1,trk.y1,4);
sprintf(filename,"%s.id",argv[1]);
file=fopen(filename,"w");
fprintf(file,"%.23s %8.3f %8.3f %8.3f %8.3f %8.5f 00001 classfd.tle\n",img.nfd+1,trk.x0,trk.y0,trk.x1,trk.y1,img.exptime);
fclose(file);
cpgend();
return 0;
}
// Read fits image
struct image read_fits(char *filename)
{
int i,j,k,l,m;
qfitsloader ql;
char key[FITS_LINESZ+1];
char val[FITS_LINESZ+1];
struct image img;
// Copy filename
strcpy(img.filename,filename);
// Image size
img.naxis1=atoi(qfits_query_hdr(filename,"NAXIS1"));
img.naxis2=atoi(qfits_query_hdr(filename,"NAXIS2"));
img.naxis3=atoi(qfits_query_hdr(filename,"NAXIS3"));
img.nframes=atoi(qfits_query_hdr(filename,"NFRAMES"));
// MJD
img.mjd=(double) atof(qfits_query_hdr(filename,"MJD-OBS"));
strcpy(img.nfd,qfits_query_hdr(filename,"DATE-OBS"));
img.exptime=atof(qfits_query_hdr(filename,"EXPTIME"));
// COSPAR ID
img.cospar=atoi(qfits_query_hdr(filename,"COSPAR"));
// Transformation
img.mjd=atof(qfits_query_hdr(filename,"MJD-OBS"));
img.ra0=atof(qfits_query_hdr(filename,"CRVAL1"));
img.de0=atof(qfits_query_hdr(filename,"CRVAL2"));
img.x0=atof(qfits_query_hdr(filename,"CRPIX1"));
img.y0=atof(qfits_query_hdr(filename,"CRPIX2"));
img.a[0]=0.0;
img.a[1]=3600.0*atof(qfits_query_hdr(filename,"CD1_1"));
img.a[2]=3600.0*atof(qfits_query_hdr(filename,"CD1_2"));
img.b[0]=0.0;
img.b[1]=3600.0*atof(qfits_query_hdr(filename,"CD2_1"));
img.b[2]=3600.0*atof(qfits_query_hdr(filename,"CD2_2"));
img.xrms=3600.0*atof(qfits_query_hdr(filename,"CRRES1"));
img.yrms=3600.0*atof(qfits_query_hdr(filename,"CRRES2"));
// Timestamps
img.dt=(float *) malloc(sizeof(float)*img.nframes);
for (i=0;i<img.nframes;i++) {
sprintf(key,"DT%04d",i);
//strcpy(val,qfits_query_hdr(filename,key));
// sscanf(val+1,"%f",&img.dt[i]);
img.dt[i]=atof(qfits_query_hdr(filename,key));
}
// Allocate image memory
img.zavg=(float *) malloc(sizeof(float)*img.naxis1*img.naxis2);
img.zstd=(float *) malloc(sizeof(float)*img.naxis1*img.naxis2);
img.zmax=(float *) malloc(sizeof(float)*img.naxis1*img.naxis2);
img.znum=(float *) malloc(sizeof(float)*img.naxis1*img.naxis2);
img.zd=(float *) malloc(sizeof(float)*img.naxis1*img.naxis2);
for (i=0;i<img.naxis1*img.naxis2;i++)
img.zd[i]=0.0;
// Set parameters
ql.xtnum=0;
ql.ptype=PTYPE_FLOAT;
ql.filename=filename;
// Loop over planes
for (k=0;k<img.naxis3;k++) {
ql.pnum=k;;
// Initialize load
if (qfitsloader_init(&ql) != 0)
printf("Error initializing data loading\n");
// Test load
if (qfits_loadpix(&ql) != 0)
printf("Error loading actual data\n");
// Fill z array
for (i=0,l=0;i<img.naxis1;i++) {
for (j=0;j<img.naxis2;j++) {
if (k==0) img.zavg[l]=ql.fbuf[l];
if (k==1) img.zstd[l]=ql.fbuf[l];
if (k==2) img.zmax[l]=ql.fbuf[l];
if (k==3) img.znum[l]=ql.fbuf[l];
if (k==3) img.zd[l]=ql.fbuf[l];
l++;
}
}
}
return img;
}
// Computes apparent position
struct sat apparent_position(double mjd)
{
struct sat s;
double jd,rsun,rearth,rsat;
double dx,dy,dz,dvx,dvy,dvz;
xyz_t satpos,obspos,obsvel,satvel,sunpos;
double ra,de;
double mjd0=51544.5;
// Sat ID
s.Isat=Isat;
// Get Julian Date
jd=mjd+2400000.5;
// Get positions
obspos_xyz(mjd,&obspos,&obsvel);
satpos_xyz(jd,&satpos,&satvel);
sunpos_xyz(jd,&sunpos);
// Sat positions
s.x=satpos.x;
s.y=satpos.y;
s.z=satpos.z;
s.vx=satvel.x;
s.vy=satvel.y;
s.vz=satvel.z;
// Sun position from satellite
dx=-satpos.x+sunpos.x;
dy=-satpos.y+sunpos.y;
dz=-satpos.z+sunpos.z;
// Distances
rsun=sqrt(dx*dx+dy*dy+dz*dz);
rearth=sqrt(satpos.x*satpos.x+satpos.y*satpos.y+satpos.z*satpos.z);
// Angles
s.psun=asin(696.0e3/rsun)*R2D;
s.pearth=asin(6378.135/rearth)*R2D;
s.p=acos((-dx*satpos.x-dy*satpos.y-dz*satpos.z)/(rsun*rearth))*R2D;
// Visibility state
if (s.p-s.pearth<-s.psun)
strcpy(s.state,"eclipsed");
else if (s.p-s.pearth>-s.psun && s.p-s.pearth<s.psun)
strcpy(s.state,"umbra");
else if (s.p-s.pearth>s.psun)
strcpy(s.state,"sunlit");
// Position differences
dx=satpos.x-obspos.x;
dy=satpos.y-obspos.y;
dz=satpos.z-obspos.z;
dvx=satvel.x-obsvel.x;
dvy=satvel.y-obsvel.y;
dvz=satvel.z-obsvel.z;
// Celestial position
s.r=sqrt(dx*dx+dy*dy+dz*dz);
s.v=(dvx*dx+dvy*dy+dvz*dz)/s.r;
ra=modulo(atan2(dy,dx)*R2D,360.0);
de=asin(dz/s.r)*R2D;
// Precess
precess(mjd,ra,de,mjd0,&s.ra,&s.de);
// Phase
s.phase=acos(((obspos.x-satpos.x)*(sunpos.x-satpos.x)+(obspos.y-satpos.y)*(sunpos.y-satpos.y)+(obspos.z-satpos.z)*(sunpos.z-satpos.z))/(rsun*s.r))*R2D;
// Magnitude
if (strcmp(s.state,"sunlit")==0)
s.mag=STDMAG-15.0+5*log10(s.r)-2.5*log10(sin(s.phase*D2R)+(M_PI-s.phase*D2R)*cos(s.phase*D2R));
else
s.mag=15;
/*
// Convert and project
if (strcmp(m.orientation,"horizontal")==0) {
equatorial2horizontal(mjd,s.ra,s.de,&s.azi,&s.alt);
forward(s.azi,s.alt,&s.rx,&s.ry);
} else if (strcmp(m.orientation,"equatorial")==0) {
forward(s.ra,s.de,&s.rx,&s.ry);
}
*/
return s;
}
// Greenwich Mean Sidereal Time
double gmst(double mjd)
{
double t,gmst;
t=(mjd-51544.5)/36525.0;
gmst=modulo(280.46061837+360.98564736629*(mjd-51544.5)+t*t*(0.000387933-t/38710000),360.0);
return gmst;
}
// Return x modulo y [0,y)
double modulo(double x,double y)
{
x=fmod(x,y);
if (x<0.0) x+=y;
return x;
}
// Observer position
void obspos_xyz(double mjd,xyz_t *pos,xyz_t *vel)
{
double ff,gc,gs,theta,s,dtheta;
s=sin(m.lat*D2R);
ff=sqrt(1.0-FLAT*(2.0-FLAT)*s*s);
gc=1.0/ff+m.alt/XKMPER;
gs=(1.0-FLAT)*(1.0-FLAT)/ff+m.alt/XKMPER;
theta=gmst(mjd)+m.lng;
dtheta=dgmst(mjd)*D2R/86400;
pos->x=gc*cos(m.lat*D2R)*cos(theta*D2R)*XKMPER;
pos->y=gc*cos(m.lat*D2R)*sin(theta*D2R)*XKMPER;
pos->z=gs*sin(m.lat*D2R)*XKMPER;
vel->x=-gc*cos(m.lat*D2R)*sin(theta*D2R)*XKMPER*dtheta;
vel->y=gc*cos(m.lat*D2R)*cos(theta*D2R)*XKMPER*dtheta;
vel->z=0.0;
return;
}
// Solar position
void sunpos_xyz(double mjd,xyz_t *pos)
{
double jd,t,l0,m,e,c,r;
double n,s,ecl,ra,de;
jd=mjd+2400000.5;
t=(jd-2451545.0)/36525.0;
l0=modulo(280.46646+t*(36000.76983+t*0.0003032),360.0)*D2R;
m=modulo(357.52911+t*(35999.05029-t*0.0001537),360.0)*D2R;
e=0.016708634+t*(-0.000042037-t*0.0000001267);
c=(1.914602+t*(-0.004817-t*0.000014))*sin(m)*D2R;
c+=(0.019993-0.000101*t)*sin(2.0*m)*D2R;
c+=0.000289*sin(3.0*m)*D2R;
r=1.000001018*(1.0-e*e)/(1.0+e*cos(m+c));
n=modulo(125.04-1934.136*t,360.0)*D2R;
s=l0+c+(-0.00569-0.00478*sin(n))*D2R;
ecl=(23.43929111+(-46.8150*t-0.00059*t*t+0.001813*t*t*t)/3600.0+0.00256*cos(n))*D2R;
ra=atan2(cos(ecl)*sin(s),cos(s));
de=asin(sin(ecl)*sin(s));
pos->x=r*cos(de)*cos(ra)*XKMPAU;
pos->y=r*cos(de)*sin(ra)*XKMPAU;
pos->z=r*sin(de)*XKMPAU;
return;
}
// Greenwich Mean Sidereal Time
double dgmst(double mjd)
{
double t,dgmst;
t=(mjd-51544.5)/36525.0;
dgmst=360.98564736629+t*(0.000387933-t/38710000);
return dgmst;
}
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