int main (int argc, char **argv) { int nt; /* number of time samples */ int nz; /* number of migrated depth samples */ int nx,nxshot; /* number of midpoints,shotgathers, the folds in a shot gather */ int flag=1; /*flag to use ft or meter as the unit*/ int dip=65; /*maximum dip angle to migrate*/ int iz,iw,ix,it,oldsx; /* loop counters*/ int ntfft; /* fft size*/ int nw; /* number of wave numbers */ int mytid,tids[NNTASKS],msgtype,rc,i;/*variable for PVM function*/ int nw1,task; int lpad=9999,rpad=9999; /*zero-traces padded on left and right sides*/ float f1,f2,f3,f4; /*frequencies to build the Hamming window*/ int nf1,nf2,nf3,nf4; /*the index for above frequencies*/ int NTASKS=0; /*number of slave tasks to start*/ char cpu_name[NNTASKS][80]; /*strings to store the computers' name*/ int flag_cpu=0; /*flag to control if using NTASKS variable*/ float sx,gxmin,gxmax; /*location of geophone and receivers*/ int isx,nxo,ifx=0; /*index for geophone and receivers*/ int ix1,ix2,ix3,il,ir; /*dummy index*/ float *wl,*wtmp; /*pointers for the souce function*/ float Fmax=25; /*peak frequency to make the Ricker wavelet*/ int ntw,truenw; /*number of frequencies to be migrated*/ float dt=0.004,dz; /*time, depth sampling interval*/ float ft; /*first time sample*/ float dw; /*frequency sampling interval*/ float fw; /*first frequency*/ float dx; /*spatial sampling interval*/ float **p,**cresult,**result_tmp; /* input, output data*/ float **v; /*double pointer direct to velocity structure*/ complex *wlsp,**cp,**cq,**cq1; /*pointers for internal usage*/ char *vfile=""; /* name of file containing velocities */ char *cpufile=""; /* name of file containing CPU name */ FILE *vfp,*cpu_fp; /* hook up getpar to handle the parameters */ initargs(argc,argv); requestdoc(1); /* get optional parameters */ if (!getparfloat("ft",&ft)) ft = 0.0; if (!getparint("nz",&nz)) err("nz must be specified"); if (!getparfloat("dz",&dz)) err("dz must be specified"); if (!getparstring("vfile", &vfile)) err("vfile must be specified"); if (!getparint("nxo",&nxo)) err("nxo must be specified"); if (!getparint("nxshot",&nxshot)) err("nshot must be specified"); if (!getparfloat("Fmax",&Fmax)) err("Fmax must be specified"); 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("flag",&flag)) flag=1; if (!getparint("dip",&dip)) dip=65; if (getparstring("cpufile", &cpufile)){ cpu_fp=fopen(cpufile,"r"); NTASKS=0; while(!feof(cpu_fp)){ fscanf(cpu_fp,"%s",cpu_name[NTASKS]); NTASKS++; } NTASKS-=1; flag_cpu=1; } else /*if cpufile not specified, the use NTASKS*/ if (!getparint("NTASKS",&NTASKS)) err("No CPUfile specified, NTASKS must be specified"); /*allocate space for the velocity profile*/ tshot=nxshot; v=alloc2float(nxo,nz); /*load velicoty file*/ vfp=efopen(vfile,"r"); efread(v[0],FSIZE,nz*nxo,vfp); efclose(vfp); /*PVM communication starts here*/ mytid=pvm_mytid(); /*get my pid*/ task=NTASKS; warn("\n %d",task); rc=0; /*spawn slave processes here*/ if(!flag_cpu){ rc=pvm_spawn(child,NULL,PvmTaskDefault,"",task,tids); } else{ for(i=0;i<NTASKS;i++){ rc+=pvm_spawn(child,NULL,PvmTaskHost,cpu_name[i],1,&tids[i]); } } /*show the pid of slaves if*/ for(i=0;i<NTASKS;i++){ if(tids[i]<0)warn("\n %d",tids[i]); else warn("\nt%x\t",tids[i]); } /*if not all the slaves start, then quit*/ if(rc<NTASKS){ warn("error");pvm_exit();exit(1);} /*broadcast the global parameters nxo,nz,dip to all slaves*/ pvm_initsend(PvmDataDefault); rc=pvm_pkint(&nxo,1,1); rc=pvm_pkint(&nz,1,1); rc=pvm_pkint(&dip,1,1); msgtype=PARA_MSGTYPE; task=NTASKS; rc=pvm_mcast(tids,task,msgtype); /*broadcast the velocity profile to all slaves*/ pvm_initsend(PvmDataDefault); rc=pvm_pkfloat(v[0],nxo*nz,1); msgtype=VEL_MSGTYPE; rc=pvm_mcast(tids,task,msgtype); /*free the space for velocity profile*/ free2float(v); /*loop over shot gathers begin here*/ loop: /* get info from first trace */ if (!gettr(&tr)) err("can't get first trace"); nt = tr.ns; /* 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; 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; warn("tr.d2 not set, assuming d2=1.0"); } } sx=tr.sx; isx=sx/dx; gxmin=gxmax=tr.gx; oldsx=sx; /* 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 frequency to migrated*/ truenw=nf4-nf1+1; fw=0.0+nf1*dw; warn("nf1=%d nf2=%d nf3=%d nf4=%d nw=%d",nf1,nf2,nf3,nf4,truenw); fw=0.0; /* allocate space */ wl=alloc1float(ntfft); wlsp=alloc1complex(nw); /*generate the Ricker wavelet*/ wtmp=ricker(Fmax,dt,&ntw); for(it=0;it<ntfft;it++) wl[it]=0.0; for(it=0;it<ntw-12;it++) wl[it]=wtmp[it+12]; free1float( wtmp); /*Fourier transform the Ricker wavelet to frequency domain*/ pfarc(-1,ntfft,wl,wlsp); /* allocate space */ p = alloc2float(ntfft,nxo); cp = alloc2complex(nw,nxo); for (ix=0; ix<nxo; ix++) for (it=0; it<ntfft; it++) p[ix][it] = 0.0; /*read in a single shot gather*/ ix=tr.gx/dx; memcpy( (void *) p[ix], (const void *) tr.data,nt*FSIZE); nx = 0; while(gettr(&tr)){ int igx; if(tr.sx!=oldsx){ fseek(stdin,(long)(-240-nt*4),SEEK_CUR); break;} igx=tr.gx/dx; memcpy( (void *) p[igx], (const void *) tr.data,nt*FSIZE); if(gxmin>tr.gx)gxmin=tr.gx; if(gxmax<tr.gx)gxmax=tr.gx; nx++; oldsx=tr.sx; } warn("\nnx= %d",nx); warn("sx %f , gxmin %f gxmax %f",sx,gxmin,gxmax); /*transform the shot gather from time to frequency domain*/ pfa2rc(1,1,ntfft,nxo,p[0],cp[0]); /*compute the most left and right index for the migrated section*/ ix1=sx/dx; ix2=gxmin/dx; ix3=gxmax/dx; if(ix1>=ix3)ix3=ix1; if(ix1<=ix2)ix2=ix1; il=ix2; ir=ix3; 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; /*allocate space*/ cq = alloc2complex(nx,nw); cq1 = 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||iw>nf4) cq[iw][ix]=cmplx(0.0,0.0); else{ if(iw>=nf1&&iw<=nf2){tmpp=PI/(nf2-nf1);tmppp=tmpp*(iw-nf1)-PI;tmpp=0.54+0.46*cos(tmppp); cq[iw][ix]=crmul(cp[ix+ix2][iw],tmpp);} else{ if(iw>=nf3&&iw<=nf4){tmpp=PI/(nf4-nf3);tmppp=tmpp*(iw-nf3);tmpp=0.54+0.46*cos(tmppp); cq[iw][ix]=crmul(cp[ix+ix2][iw],tmpp);} else {cq[iw][ix]=cp[ix+ix2][iw];} } } cq[iw][ix]=cp[ix+ix2][iw]; cq1[iw][ix]=cmplx(0.0,0.0); } ix=sx/dx-ifx; warn("ix %d",ix); for(iw=0;iw<nw;iw++){ cq1[iw][ix-ix2]=wlsp[iw]; } free2float(p); free2complex(cp); free1float(wl); free1complex(wlsp); /*if the horizontal spacing interval is in feet, convert it to meter*/ if(!flag) dx*=0.3048; /*start of the timing function*/ time(&t1); /* send local parameters to all slaves*/ pvm_initsend(PvmDataDefault); ix=15; rc=pvm_pkint(&ix,1,1); rc=pvm_pkint(&ntfft,1,1); rc=pvm_pkint(&ix2,1,1); rc=pvm_pkint(&ix3,1,1); rc=pvm_pkint(&isx,1,1); rc=pvm_pkint(&il,1,1); rc=pvm_pkint(&ir,1,1); rc=pvm_pkfloat(&dx,1,1); rc=pvm_pkfloat(&dz,1,1); rc=pvm_pkfloat(&dw,1,1); rc=pvm_pkfloat(&dt,1,1); msgtype=PARA_MSGTYPE; task=NTASKS; rc=pvm_mcast(tids,task,msgtype); /* send all the frequency to slaves*/ count=NTASKS*5; /*count is the number of frequency components in a shot gather*/ nw=truenw; nw1=nw/(count); if(nw1==0)nw1=1; total=count=ceil(nw*1.0/nw1); /* if it is the first shot gather, send equal data to all the slaves, then for the following shot gathers, only send data when slave requests*/ if(nxshot==tshot){ for(i=0;i<NTASKS;i++){ float *tmpp; float fw1; int nww,byte,nwww; pvm_initsend(PvmDataDefault); nww=nf1+i*nw1;fw1=fw+nww*dw; nwww=nw1; byte=UnDone; rc=pvm_pkint(&byte,1,1); rc=pvm_pkfloat(&fw1,1,1); rc=pvm_pkint(&nwww,1,1); rc=pvm_pkfloat((float *)cq[nww],nx*nwww*2,1); rc=pvm_pkfloat((float *)cq1[nww],nx*nwww*2,1); msgtype=DATA_MSGTYPE; pvm_send(tids[i],msgtype); } count-=NTASKS; } while(count){ int tid0,bufid; float *tmpp; float fw1; int nww,byte,nwww; int i; i=total-count; msgtype=COM_MSGTYPE; bufid=pvm_recv(-1,msgtype); rc=pvm_upkint(&tid0,1,1); pvm_freebuf(bufid); pvm_initsend(PvmDataDefault); nww=nf1+i*nw1;fw1=fw+nww*dw; if(i==total-1)nwww=nw-nw1*i; else nwww=nw1; byte=UnDone; rc=pvm_pkint(&byte,1,1); rc=pvm_pkfloat(&fw1,1,1); rc=pvm_pkint(&nwww,1,1); rc=pvm_pkfloat((float *)cq[nww],nx*nwww*2,1); rc=pvm_pkfloat((float *)cq1[nww],nx*nwww*2,1); msgtype=DATA_MSGTYPE; pvm_send(tid0,msgtype); count--; } ix=Done; pvm_initsend(PvmDataDefault); rc=pvm_pkint(&ix,1,1); msgtype=DATA_MSGTYPE; pvm_mcast(tids,task,msgtype); free2complex(cq); free2complex(cq1); time(&t2); warn("\n %d shot been finished in %f seconds, Ntask=%d",nxshot,difftime(t2,t1),NTASKS); nxshot--; if(nxshot)goto loop; /*when all the shot gathers done, send signal to all slaves to request the partial imaging*/ ix=FinalDone; pvm_initsend(PvmDataDefault); rc=pvm_pkint(&ix,1,1); msgtype=PARA_MSGTYPE; pvm_mcast(tids,task,msgtype); /*allocate space for the final image*/ cresult = alloc2float(nz,nxo); for(ix=0;ix<nxo;ix++) for(iz=0;iz<nz;iz++) { cresult[ix][iz]=0.0; } result_tmp= alloc2float(nz,nxo); /*receive partial image from all the slaves*/ msgtype=RESULT_MSGTYPE; i=0; while(i<NTASKS){ int bufid; bufid=pvm_recv(-1,msgtype); rc=pvm_upkfloat(result_tmp[0],nxo*nz,1); pvm_freebuf(bufid); for(ix=0;ix<nxo;ix++) for(iz=0;iz<nz;iz++) { cresult[ix][iz]+=result_tmp[ix][iz]; } i=i+1; warn("\n i=%d been received",i); } /*send signal to all slaves to kill themselves*/ pvm_initsend(PvmDataDefault); pvm_mcast(tids,task,COM_MSGTYPE); /*output the final image*/ for(ix=0; ix<nxo; ix++){ tr.ns = nz ; tr.dt = dz*1000000.0 ; tr.d2 = dx; tr.offset = 0; tr.cdp = tr.tracl = ix; memcpy( (void *) tr.data, (const void *) cresult[ix],nz*FSIZE); puttr(&tr); } pvm_exit(); return EXIT_SUCCESS; }
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 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 iz,iw,ix,it,ik; /* loop counters */ int igx; /* integerized gx value */ int ntfft,nxfft; /* fft size */ int nw,truenw,nk; /* number of wave numbers */ int dip=65; /* dip angle */ int oldigx=0; /* old value of integerized gx value */ int oldisx=0; /* old value of integerized sx value */ 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 ix1,ix2,ix3,ixshot,il=0,ir=0; /* 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,dk; /* wavenumber and frequency sampling interval */ float fw,fk; /* first wavenumber and frequency */ float w,k; /* wavenumber and frequency */ float dx; /* spatial sampling interval */ float **p=NULL; float **cresult=NULL; /* input, output data */ float v1,vmin; double kz1,kz2; double phase1; float **v=NULL; float **vp=NULL; complex cshift1,cshift2; complex *wlsp=NULL; complex **cp=NULL; complex **cp1=NULL; complex **cq=NULL; complex **cq1=NULL; /*complex input,output*/ 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 optional parameters */ MUSTGETPARINT("nz",&nz); MUSTGETPARFLOAT("dz",&dz); MUSTGETPARSTRING("vfile", &vfile); MUSTGETPARINT("nxo",&nxo); MUSTGETPARINT("nxshot",&nxshot); if (!getparfloat("fmax",&fmax)) fmax = 25. ; 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=65; if (!getparint("verbose",&verbose)) verbose = 0; /* allocate space */ cresult = alloc2float(nz,nxo); vp=alloc2float(nxo,nz); /* load velocity 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); if (!gettr(&tr)) err("can't get first trace"); nt = tr.ns; get_sx_gx(&sx,&gx); min_sx_gx = MIN(sx,gx); gxmin=gxmax=gx; erewind(stdin); /* 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; 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; warn("tr.d2 not set, assuming d2=1.0"); } } 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]; } */ /* warn("%12i %12f \n",(it-ntw/2+ntfft) % ntfft,wtmp[it]); */ /* End of new code */ free1float(wtmp); /* fourier transform wl array */ pfarc(-1,ntfft,wl,wlsp); /* CS TEST: this was used to output the array wlsp (the wavelet in the frequency domain) to the file CSinfo, no longer needed and commented out */ /* FILE *CSinfo; CSinfo=fopen("CSinfo","w"); fprintf(CSinfo,"ntfft=%10i\n",ntfft); fprintf(CSinfo,"ntw=%10i\n",ntw); for(iw=0;iw<ntfft/2+1;iw++) fprintf(CSinfo,"%12f %12f \n",wlsp[iw].r,wlsp[iw].i); fclose(CSinfo); */ /* conclusion from the analysis of this info: the wavelet (whose fourier transform is in wlsp) is not zero phase!!! so there is a timeshift error!!! Conclusion obtained dec 11 2005 */ /* CS */ /* 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; if (gx < 0 ) { igx=gx/dx + nxo; } else { igx=gx/dx ; } oldigx=igx; oldsx=sx; oldgx=gx; oldgxmax=gxmax; oldgxmin=gxmin; while(gettr(&tr)) { /* begin looping over traces within a shot gather */ /* get sx and gx */ get_sx_gx(&sx,&gx); /* warn("%d nx=%d", igx, nx); sx = (sx - min_sx_gx); gx = (gx - min_sx_gx); */ if (gx < 0 ) { igx=gx/dx + nxo; } else { igx=gx/dx ; } if (igx==oldigx) warn("repeated igx!!! check dx or scalco value!!!"); oldigx = igx; if(tr.sx!=oldsx){ efseeko(stdin,(off_t)(-240-nt*4),SEEK_CUR); break;} 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!"); memcpy( (void *) p[igx], (const void *) tr.data,nt*FSIZE); ++nx; } isx=oldsx/dx; if (isx==oldisx) warn("repeated isx!!! check dx or scalco value!!!"); oldisx=isx; ixshot=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=oldsx/dx; ix2=gxmin/dx; ix3=gxmax/dx; if(ix1>=ix3)ix3=ix1; if(ix1<=ix2)ix2=ix1; il=ix2; ir=ix3; 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; /* determine wavenumber sampling (for complex to complex FFT) */ nxfft = npfa(nx); nk = nxfft; dk = 2.0*PI/(nxfft*dx); fk = -PI/dx; /* 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); /* allocating space */ cq=alloc2complex(nxfft,nw); cq1=alloc2complex(nxfft,nw); /* 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 minimum velocity */ vmin=0; for(ix=il-ix2;ix<=ir-ix2;ix++){ vmin+=1.0/v[iz][ix]/(ir-il+1); } vmin=1.0/vmin; /* compute the shifted wavefield */ for (ik=0;ik<nx;++ik) { for (iw=0; iw<nw; ++iw) { cq[iw][ik] = ik%2 ? cneg(cp[iw][ik]) : cp[iw][ik]; cq1[iw][ik] = ik%2 ? cneg(cp1[iw][ik]) : cp1[iw][ik]; } } /* zero out cq[][] cq1[][] */ for (ik=nx; ik<nk; ++ik) { for (iw=0; iw<nw; ++iw) { cq[iw][ik] = cmplx(0.0,0.0); cq1[iw][ik] = cmplx(0.0,0.0); } } /* FFT to W-K domain */ pfa2cc(-1,1,nk,nw,cq[0]); pfa2cc(-1,1,nk,nw,cq1[0]); v1=vmin; for(ik=0,k=fk;ik<nk;++ik,k+=dk) { for(iw=0,w=fw;iw<nw;++iw,w+=dw){ if(w==0.0)w=1.0e-10/dt; kz1=1.0-pow(v1*k/w,2.0); if(kz1>0.15){ phase1 = -w*sqrt(kz1)*dz/v1; cshift1 = cmplx(cos(phase1), sin(phase1)); cq[iw][ik] = cmul(cq[iw][ik],cshift1); cq1[iw][ik] = cmul(cq1[iw][ik],cshift1); } else { cq[iw][ik] = cq1[iw][ik] = cmplx(0.0,0.0); } } } pfa2cc(1,1,nk,nw,cq[0]); pfa2cc(1,1,nk,nw,cq1[0]); for(ix=0;ix<nx;++ix) { for(iw=0,w=fw;iw<nw;w+=dw,++iw){ float a=0.015,g=1.0; int I=10; if(ix<=I)g=exp(-a*(I-ix)*(I-ix)); if(ix>=nx-I)g=exp(-a*(-nx+I+ix)*(-nx+I+ix)); cq[iw][ix] = crmul( cq[iw][ix],1.0/nxfft); cq[iw][ix] =ix%2 ? cneg(cq[iw][ix]) : cq[iw][ix]; kz2=(1.0/v1-1.0/v[iz][ix])*w*dz; cshift2=cmplx(cos(kz2),sin(kz2)); cp[iw][ix]=cmul(cq[iw][ix],cshift2); cq1[iw][ix] = crmul( cq1[iw][ix],1.0/nxfft); cq1[iw][ix] =ix%2 ? cneg(cq1[iw][ix]) : cq1[iw][ix]; cp1[iw][ix]=cmul(cq1[iw][ix],cshift2); } } } free2complex(cp); free2complex(cp1); free2complex(cq); free2complex(cq1); 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()); }