int
main (int argc, char **argv)
{
int nt; /* number of time samples */
int nz; /* number of migrated depth samples */
int nx; /* number of horizontal samples */
int nxshot; /* number of shots to be migrated */
/*int nxshot_orig;*/ /* first value of nxshot */
int iz,iw,ix,it; /* loop counters */
int igx; /* integerized gx value */
int ntfft; /* fft size */
int nw,truenw; /* number of wave numbers */
int dip=79; /* dip angle */
float sx,gx; /* x source and geophone location */
float gxmin=0.0,gxmax=0.0; /* x source and geophone location */
float min_sx_gx; /* min(sx,gx) */
float oldgx; /* old gx position */
/* float oldgxmin; */ /* old gx position */
/* float oldgxmax; */ /* old gx position */
float oldsx=0.0; /* old sx position */
int isx=0,nxo; /* index for source and geophone */
int oldisx=0; /* old value of source index */
int oldigx=0; /* old value of integerized gx value */
int ix1,ix2,ix3,ixshot; /* dummy index */
int lpad,rpad; /* padding on both sides of the migrated section */
float *wl=NULL,*wtmp=NULL;
float fmax;
float f1,f2,f3,f4;
int nf1,nf2,nf3,nf4;
int ntw;
float dt=0.004,dz; /* time and depth sampling interval */
float dw; /* frequency sampling interval */
float fw; /* first frequency */
float w; /* frequency */
float dx; /* spatial sampling interval */
float **p=NULL; /* input data */
float **cresult=NULL; /* output result */
float v1; /* average velocity */
double kz2;
float **v=NULL,**vp=NULL;/* pointers for the velocity profile */
complex cshift2;
complex *wlsp=NULL; /* complex input,output */
complex **cp=NULL; /* ... */
complex **cp1=NULL; /* ... */
complex **cq=NULL; /* ... */
char *vfile=""; /* name of file containing velocities */
FILE *vfp=NULL;
int verbose; /* verbose flag */
/* hook up getpar to handle the parameters */
initargs(argc,argv);
requestdoc(1);
/* get required parameters */
MUSTGETPARINT("nz",&nz);
MUSTGETPARINT("nxo",&nxo);
MUSTGETPARFLOAT("dz",&dz);
MUSTGETPARSTRING("vfile",&vfile);
MUSTGETPARINT("nxshot",&nxshot);
/* get optional parameters */
if (!getparfloat("fmax",&fmax)) fmax = 25.0;
if (!getparfloat("f1",&f1)) f1 = 10.0;
if (!getparfloat("f2",&f2)) f2 = 20.0;
if (!getparfloat("f3",&f3)) f3 = 40.0;
if (!getparfloat("f4",&f4)) f4 = 50.0;
if (!getparint("lpad",&lpad)) lpad=9999;
if (!getparint("rpad",&rpad)) rpad=9999;
if (!getparint("dip",&dip)) dip=79;
if (!getparint("verbose",&verbose)) verbose = 0;
/* allocating space */
cresult = alloc2float(nz,nxo);
vp = alloc2float(nxo,nz);
/* load velicoty file */
vfp=efopen(vfile,"r");
efread(vp[0],FSIZE,nz*nxo,vfp);
efclose(vfp);
/* zero out cresult array */
memset((void *) cresult[0], 0, nxo*nz*FSIZE);
/* save value of nxshot */
/* nxshot_orig=nxshot; */
/* get info from first trace */
if (!gettr(&tr)) err("can't get first trace");
nt = tr.ns;
get_sx_gx(&sx,&gx);
min_sx_gx = MIN(sx,gx);
sx = sx - min_sx_gx;
gx = gx - min_sx_gx;
/* let user give dt and/or dx from command line */
if (!getparfloat("dt", &dt)) {
if (tr.dt) { /* is dt field set? */
dt = ((double) tr.dt)/1000000.0;
} else { /* dt not set, assume 4 ms */
dt = 0.004;
if(verbose) warn("tr.dt not set, assuming dt=0.004");
}
}
if (!getparfloat("dx",&dx)) {
if (tr.d2) { /* is d2 field set? */
dx = tr.d2;
} else {
dx = 1.0;
if(verbose) warn("tr.d2 not set, assuming d2=1.0");
}
}
checkpars();
oldisx=0;
do { /* begin loop over shots */
/* determine frequency sampling interval*/
ntfft = npfar(nt);
nw = ntfft/2+1;
dw = 2.0*PI/(ntfft*dt);
/* compute the index of the frequency to be migrated*/
fw=2.0*PI*f1;
nf1=fw/dw+0.5;
fw=2.0*PI*f2;
nf2=fw/dw+0.5;
fw=2.0*PI*f3;
nf3=fw/dw+0.5;
fw=2.0*PI*f4;
nf4=fw/dw+0.5;
/* the number of frequencies to migrated*/
truenw=nf4-nf1+1;
fw=0.0+nf1*dw;
if(verbose)
warn("nf1=%d nf2=%d nf3=%d nf4=%d nw=%d",nf1,nf2,nf3,nf4,truenw);
/* allocate space */
wl=alloc1float(ntfft);
wlsp=alloc1complex(nw);
/* generate the Ricker wavelet */
wtmp=ricker(fmax,dt,&ntw);
/* zero out wl[] array */
memset((void *) wl, 0, ntfft*FSIZE);
/* CHANGE BY CHRIS STOLK, Dec. 11, 2005 */
/* The next two lines are the old code, */
/* it is erroneous because the peak of */
/* the wavelet occurs at positive time */
/* instead of time zero. */
/*
for(it=0;it<ntw;it++)
wl[it]=wtmp[it];
*/
/* New code: we put in the wavelet in a centered fashion */
for(it=0;it<ntw;it++)
wl[(it-ntw/2+ntfft) % ntfft]=wtmp[it];
/* End of new code */
free1float(wtmp);
/* fourier transform wl array */
pfarc(-1,ntfft,wl,wlsp);
/* allocate space */
p = alloc2float(ntfft,nxo);
cq = alloc2complex(nw,nxo);
/* zero out p[][] array */
memset((void *) p[0], 0, ntfft*nxo*FSIZE);
/* initialize a number of items before looping over traces */
nx = 0;
igx=0;
oldigx=0;
oldsx=sx;
oldgx=gx;
/* oldgxmax=gxmax; */
/* oldgxmin=gxmin; */
do { /* begin looping over traces within a shot gather */
memcpy( (void *) p[igx], (const void *) tr.data,nt*FSIZE);
/* get sx and gx */
get_sx_gx(&sx,&gx);
sx = (sx - min_sx_gx);
gx = (gx - min_sx_gx);
igx = NINT(gx/dx);
if (igx==oldigx)
warn("repeated igx!!! check dx or scalco value!!!");
oldigx = igx;
if(gxmin>gx)gxmin=gx;
if(gxmax<gx)gxmax=gx;
if(verbose)
warn(" inside loop: min_sx_gx %f isx %d igx %d gx %f sx %f",min_sx_gx,isx,igx,gx,sx);
/* sx, gx must increase monotonically */
if (!(oldsx <= sx) )
err("sx field must be monotonically increasing!");
if (!(oldgx <= gx) )
err("gx field must be monotonically increasing!");
++nx;
} while(gettr(&tr) && sx==oldsx);
isx=NINT(oldsx/dx);
ixshot=isx;
if (isx==oldisx)
warn("repeated isx!!! check dx or scalco value!!!");
oldisx=isx;
if(verbose) {
warn("sx %f, gx %f , gxmin %f gxmax %f nx %d",sx,gx,gxmin,gxmax, nx);
warn("isx %d igx %d ixshot %d" ,isx,igx,ixshot);
}
/* transform the shot gather from time to frequency domain */
pfa2rc(1,1,ntfft,nxo,p[0],cq[0]);
/* compute the most left and right index for the migrated */
/* section */
ix1=NINT(oldsx/dx);
ix2=NINT(gxmin/dx);
ix3=NINT(gxmax/dx);
if(ix1>=ix3)ix3=ix1;
if(ix1<=ix2)ix2=ix1;
ix2-=lpad;
ix3+=rpad;
if(ix2<0)ix2=0;
if(ix3>nxo-1)ix3=nxo-1;
/* the total traces to be migrated */
nx=ix3-ix2+1;
nw=truenw;
/* allocate space for velocity profile within the aperature */
v=alloc2float(nx,nz);
for(iz=0;iz<nz;iz++)
for(ix=0;ix<nx;ix++)
v[iz][ix]=vp[iz][ix+ix2];
/* allocate space */
cp = alloc2complex(nx,nw);
cp1 = alloc2complex(nx,nw);
/* transpose the frequency domain data from */
/* data[ix][iw] to data[iw][ix] and apply a */
/* Hamming at the same time */
for (ix=0; ix<nx; ++ix) {
for (iw=0; iw<nw; iw++){
float tmpp=0.0,tmppp=0.0;
if(iw>=(nf1-nf1)&&iw<=(nf2-nf1)){
tmpp=PI/(nf2-nf1);
tmppp=tmpp*(iw-nf1)-PI;
tmpp=0.54+0.46*cos(tmppp);
cp[iw][ix]=crmul(cq[ix+ix2][iw+nf1],tmpp);
} else {
if(iw>=(nf3-nf1)&&iw<=(nf4-nf1)) {
tmpp=PI/(nf4-nf3);
tmppp=tmpp*(iw-nf3);
tmpp=0.54+0.46*cos(tmppp);
cp[iw][ix]=crmul(cq[ix+ix2][iw+nf1],tmpp);
} else {
cp[iw][ix]=cq[ix+ix2][iw+nf1];
}
}
cp1[iw][ix]=cmplx(0.0,0.0);
}
}
for(iw=0;iw<nw;iw++){
cp1[iw][ixshot-ix2]=wlsp[iw+nf1];
}
if(verbose) {
warn("ixshot %d ix %d ix1 %d ix2 %d ix3 %d",ixshot,ix,ix1,ix2,ix3);
warn("oldsx %f ",oldsx);
}
free2float(p);
free2complex(cq);
free1float(wl);
free1complex(wlsp);
/* loops over depth */
for(iz=0; iz<nz; ++iz) {
/* the imaging condition */
for(ix=0; ix<nx; ++ix){
for(iw=0,w=fw;iw<nw;w+=dw,iw++){
complex tmp;
float ratio=10.0;
if(fabs(ix+ix2-ixshot)*dx<ratio*iz*dz)
tmp=cmul(cp[iw][ix],cp1[iw][ix]);
else
tmp=cmplx(0.0,0.0);
cresult[ix+ix2][iz]+=tmp.r/ntfft;
}
}
/* get the average velocity */
v1=0.0;
for(ix=0;ix<nx;++ix)
v1+=v[iz][ix]/nx;
/* compute time-invariant wavefield */
for(ix=0;ix<nx;++ix) {
for(iw=0,w=fw;iw<nw;w+=dw,++iw) {
kz2=-(1.0/v1)*w*dz;
cshift2=cmplx(cos(kz2),sin(kz2));
cp[iw][ix]=cmul(cp[iw][ix],cshift2);
cp1[iw][ix]=cmul(cp1[iw][ix],cshift2);
}
}
/* wave-propagation using finite-difference method */
fdmig(cp, nx, nw,v[iz],fw,dw,dz,dx,dt,dip);
fdmig(cp1,nx, nw,v[iz],fw,dw,dz,dx,dt,dip);
/* apply thin lens term here */
for(ix=0;ix<nx;++ix) {
for(iw=0,w=fw;iw<nw;w+=dw,++iw){
kz2=-(1.0/v[iz][ix]-1.0/v1)*w*dz;
cshift2=cmplx(cos(kz2),sin(kz2));
cp[iw][ix]=cmul(cp[iw][ix],cshift2);
cp1[iw][ix]=cmul(cp1[iw][ix],cshift2);
}
}
}
free2complex(cp);
free2complex(cp1);
free2float(v);
--nxshot;
} while(nxshot);
/* restore header fields and write output */
for(ix=0; ix<nxo; ix++){
tr.ns = nz;
tr.d1 = dz;
tr.d2 = dx;
tr.offset = 0;
tr.cdp = tr.tracl = ix;
memcpy( (void *) tr.data, (const void *) cresult[ix],nz*FSIZE);
puttr(&tr);
}
return(CWP_Exit());
}
int main (int argc, char **argv)
{
int Finish,dip=65;
int nz; /* number of migrated depth samples */
int nxo,nx; /* number of midpoints */
int iz,iw,ix,ix2,ix3,ixshot; /* loop counters*/
int ntfft; /* fft size*/
int nw; /* number of frequency*/
int mytid,msgtype,rc,parent_tid;
float dt=0.004,dz; /*time and depth sampling interval*/
float dw; /*frequency sampling interval */
float fw; /* first frequency*/
float w; /* frequency*/
float dx; /* spatial sampling interval*/
float **cresult; /*output data*/
float v1;
float para;
double kz2;
float **vp,**v;
complex cshift2;
complex **cp,**cp1; /* complex input,output */
/*get my and father pids*/
mytid=pvm_mytid();
parent_tid=pvm_parent();
/*receive global parameters*/
msgtype=PARA_MSGTYPE;
rc=pvm_recv(-1,msgtype);
rc=pvm_upkint(&nxo,1,1);
rc=pvm_upkint(&nz,1,1);
rc=pvm_upkint(&dip,1,1);
rc=pvm_upkfloat(¶,1,1);
/*allocate space for velocity profile and receive velocity from father*/
vp=alloc2float(nxo,nz);
msgtype=VEL_MSGTYPE;
rc=pvm_recv(-1,msgtype);
rc=pvm_upkfloat(vp[0],nxo*nz,1);
/*allocate space for the storage of partial image and zero it out now*/
cresult = alloc2float(nz,nxo);
for(ix=0;ix<nxo;ix++)
for(iz=0;iz<nz;iz++)
cresult[ix][iz]=0.0;
/*loop over shotgather*/
loop:
/*receive parameters for each shot gather*/
msgtype=PARA_MSGTYPE;
rc=pvm_recv(parent_tid,msgtype);
rc=pvm_upkint(&Finish,1,1);
if(Finish==FinalDone)goto end;
rc=pvm_upkint(&ntfft,1,1);
rc=pvm_upkint(&ix2,1,1);
rc=pvm_upkint(&ix3,1,1);
rc=pvm_upkint(&ixshot,1,1);
nx=ix3-ix2+1;
rc=pvm_upkfloat(&dx,1,1);
rc=pvm_upkfloat(&dz,1,1);
rc=pvm_upkfloat(&dw,1,1);
rc=pvm_upkfloat(&dt,1,1);
/*allocate space for velocity profile within the aperature*/
v=alloc2float(nx,nz);
for(iz=0;iz<nz;iz++)
for(ix=0;ix<nx;ix++){
v[iz][ix]=vp[iz][ix+ix2];
}
while(1){
/*receive parameters and data for processing*/
msgtype=DATA_MSGTYPE;
rc=pvm_recv(parent_tid,msgtype);
rc=pvm_upkint(&Finish,1,1);
if(Finish==Done) {free2float(v);goto loop; }
rc=pvm_upkfloat(&fw,1,1);
rc=pvm_upkint(&nw,1,1);
cp = alloc2complex(nx,nw);
cp1 = alloc2complex(nx,nw);
rc=pvm_upkfloat((float *)cp[0],nx*nw*2,1);
rc=pvm_upkfloat((float *)cp1[0],nx*nw*2,1);
/* loops over depth */
for(iz=0;iz<nz;++iz){
/*the imaging condition*/
/* for(ix=0;ix<nx;ix++){
for(iw=0,w=fw;iw<nw;w+=dw,iw++){
complex tmp;
float ratio=10.0;
if(fabs(ix+ix2-ixshot)*dx<ratio*iz*dz)
tmp=cmul(cp[iw][ix],cp1[iw][ix]);
else tmp=cmplx(0.0,0.0);
cresult[ix+ix2][iz]+=tmp.r/ntfft;
}
}
*/
/* anothe imaging condition, slightly different from the above one, but not quite
slow*/
for(iw=0,w=fw;iw<nw;w+=dw,iw++){
float kk=0.0;
complex tmp;
float ratio=1.5;
if(dip<80)ratio=1.5;
else ratio=1.5;
for(ix=0;ix<nx;ix++){
kk+=(pow(cp1[iw][ix].i,2.0)+pow(cp1[iw][ix].r,2.0))/nx;
}
for(ix=0;ix<nx;ix++){
tmp=cmul(cp[iw][ix],cp1[iw][ix]);
if(fabs(ix+ix2-ixshot)*dx<ratio*iz*dz)
tmp=crmul(tmp,1.0/(kk+1.0e-10));
else tmp=cmplx(0.0,0.0);
cresult[ix+ix2][iz]+=tmp.r/ntfft;
}
}
/*get the average velocity*/
v1=0.0;
for(ix=0;ix<nx;++ix)
{v1+=v[iz][ix]/nx;}
/*compute time-invariant wavefield*/
/* for(ix=0;ix<nx;++ix)
for(iw=0,w=fw;iw<nw;w+=dw,++iw) {
kz2=-(1.0/v1)*w*dz;
cshift2=cmplx(cos(kz2),sin(kz2));
cp[iw][ix]=cmul(cp[iw][ix],cshift2);
cp1[iw][ix]=cmul(cp1[iw][ix],cshift2);
}
*/
/*wave-propagation using finite-difference method*/
fdmig( cp, nx, nw,v[iz],fw,dw,dz,dx,dt,dip,para);
fdmig( cp1,nx, nw,v[iz],fw,dw,dz,dx,dt,dip,para);
/*apply thin lens term here*/
for(ix=0;ix<nx;++ix)
for(iw=0,w=fw;iw<nw;w+=dw,++iw){
float Wi=-dw;
kz2=-(1.0/v[iz][ix])*dz;
/* kz2=-(1.0/v[iz][ix]-1.0/v1)*w*dz;
cshift2=cmplx(cos(kz2),sin(kz2));*/
cshift2=cexp(cmplx(-Wi*kz2,w*kz2));
cp[iw][ix]=cmul(cp[iw][ix],cshift2);
cp1[iw][ix]=cmul(cp1[iw][ix],cshift2);
}
}
/*finish a portion of the data, request more*/
pvm_initsend(PvmDataDefault);
pvm_pkint(&mytid,1,1);
msgtype=COM_MSGTYPE;
pvm_send(parent_tid,msgtype);
free2complex(cp);
free2complex(cp1);
}
end:
/*everything done,send back partial image and wait for signal to kill itself*/
pvm_initsend(PvmDataDefault);
pvm_pkfloat(cresult[0],nxo*nz,1);
msgtype=RESULT_MSGTYPE;
pvm_send(parent_tid,msgtype);
msgtype=COM_MSGTYPE;
pvm_recv(-1,msgtype);
pvm_exit();
exit(0);
}
