Esempio n. 1
0
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());	

}
Esempio n. 2
0
int
main(int argc, char **argv)
{
	cwp_String key;	/* header key word from segy.h		*/
	cwp_String type;/* ... its type				*/
	int index;	/* ... its index			*/
	int nsegy;	/* number of bytes in the segy		*/
	Value val;	/* value of key in current gather	*/
	Value valnew;	/* value of key in trace being treated	*/
	int verbose;	/* verbose flag				*/
	int val_i;	/* key value as an integer		*/

	int ntr=0;	/* count of number of traces in an ensemble */
	int numlength;	/* length of numerical part of filenames */
	
	FILE *tmpfp=NULL;		/* file pointer			*/
	FILE *outfp=NULL;	/* file pointer			*/
	cwp_String dir;		/* directory name		*/
	cwp_String suffix;	/* suffix of output files	*/

	char directory[BUFSIZ];		/* storage for directory name	*/
 	char tempfilename[BUFSIZ];	/* 	...temporary filename	*/
	char middle[BUFSIZ];		/*      ...middle of final filename */
	char stem[BUFSIZ];		/*      ...stem of final filename */
 	char format[BUFSIZ];		/* 	...format of numeric part */
	char outfile[BUFSIZ];		/*      ...final filename	*/

	/* Initialize */
	initargs(argc, argv);
	requestdoc(1);


	/* Get parameters */
	MUSTGETPARSTRING("dir", &dir);
	if (!getparint   ("verbose", &verbose))	 	verbose = 0;
	if (!getparstring("key", &key))		 	key = "ep";
	if (!getparstring("suffix", &suffix))		suffix = ".hsu";
	if (!getparint("numlength", &numlength)) 	numlength=7;

	/* Initialize */
	/* tempfilename = ealloc1(strlen(tmplt)+3,sizeof(char)); */
	type = hdtype(key);
	index = getindex(key);

	/* Set up for first trace (must compare new key field each time) */
	nsegy = gettr(&intrace);
	
	/* Create temporary filename for the first gather */
	strcpy(directory, dir);
	strcpy(tempfilename, temporary_filename(directory));
	if((tmpfp = fopen(tempfilename,"w+")) == NULL)
		err("Cannot open file %s\n",tempfilename);

	if (verbose) warn(" temporary filename = %s", tempfilename);

	/* get key header value */
	gethval(&intrace, index, &val);
	
	ntr=0;
	do {

		++ntr;
		/* Get header value */				 
		gethval(&intrace, index, &valnew);

		/* compare past header value to current value */
		if (valcmp(type, val, valnew) || !nsegy) {
		 /* Either val and valnew differ, indicating a  */
		 /* new gather or nsegy is zero, indicating the */
		 /* end of the traces.			  */
			
			/* capture key field value */
			/* and build output filename */
			val_i=vtoi(type,val);

			/* zero out name parts */
			strcpy(outfile,"");
			strcpy(middle,"");
			strcpy(stem,"");

			/* build output name parts */
			strcat(middle,directory);
			strcat(middle,"/");
			strcat(stem,key);
			strcat(stem,"=");

			/* format for numeric part */
			(void)sprintf(format, "%%s%%s%%0%dd%%s",numlength);
		
			/* build name of output file */
			(void)sprintf(outfile, format,middle,stem,
					val_i, suffix);

			if (verbose) warn(" outfile = %s", outfile);

			/* rewind file */
			rewind(tmpfp);

			/* open the new file */
			if((outfp = fopen(outfile,"w+")) == NULL)
				err("Cannot open file %s\n",outfile);
			/* loop over traces setting ntr field */
			/*  and write to finalfile */	
			while(fgettr(tmpfp,&tmptr))  {
				tmptr.ntr = ntr;
				fputtr(outfp,&tmptr);
			}
			/* Close files */
			fclose(tmpfp);
			fclose(outfp);
			remove(tempfilename);

			if (verbose) warn("val= %i", val_i);

			/* Set up for next gather */
			/* create new tempfname first */
			strcpy(tempfilename, temporary_filename(directory));
			
			/* open filename */
			if((tmpfp = fopen(tempfilename,"w+")) == NULL)
				err("Cannot open file %s\n",tempfilename);
			val = valnew;
			ntr=0;
		}
		fputtr(tmpfp,&intrace);
	} while(gettr(&intrace));
	
	/* Close file */
	rewind(tmpfp);
	val_i=vtoi(type,val);
	
	/* Move last gather into new location */
	/* capture key field value */
	/* and build output filename */

	/* null out name parts */
	strcpy(outfile,"");
	strcpy(middle,"");
	strcpy(stem,"");

	/* build name parts */
	strcat(middle,directory);
	strcat(middle,"/");
	strcat(stem,key);
	strcat(stem,"=");
	
	/* write format of numeric part of output filename */
	(void)sprintf(format, "%%s%%s%%0%dd%%s",numlength);

	/* write output filename */
	(void)sprintf(outfile, format,middle,stem,
				val_i, suffix);

	/* open the output file */
	if((outfp = fopen(outfile,"w+")) == NULL)
			err("Cannot open file %s\n",outfile);
	/* loop over traces setting ntr field */
	while(fgettr(tmpfp,&tmptr))  {
		tmptr.ntr = ntr;
		fputtr(outfp,&tmptr);
	}
	/* Close file */
	fclose(tmpfp);
	fclose(outfp);
	remove(tempfilename);

	if (verbose) warn(" outfile = %s", outfile);
	if (verbose) warn("val= %i",val_i);

	return(CWP_Exit());

}
Esempio n. 3
0
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());	

}
Esempio n. 4
0
int main( int argc, char *argv[] )
{
        int ntr=0;                /* number of traces                     */
        int ntrv=0;               /* number of traces                     */
	int ns=0;
	int nsv=0;
	float dt;
	float dtv;
	
	cwp_String fs;
	cwp_String fv;
	FILE *fps;
	FILE *fpv;
	FILE *headerfp;
		
	float *data;		/* data matrix of the migration volume */
	float *vel;		/* velocity matrix */
	float *velfi;		/* velocity function interpolated to ns values*/
	float *velf;		/* velocity function */
	float *vdt;
	float *ddt;
	float *ap;		/* array of apperture values in m */
	float apr;		/* array of apperture values in m */
	int *apt=NULL;		/* array of apperture time limits in mig. gath*/
	float   r;		/* maximum radius with a given apperture */
	float ir2;		/* r/d2 */
	float ir3;		/* r/d3 */
	float d2;		/* spatial sampling int. in dir 2. */
	float d3;		/* spatial sampling int. in dir 3. */
	float **mgd=NULL;	/* migration gather data */
	float *migt;		/* migrated data trace */
	int **mgdnz=NULL;		/* migration gather data non zero samples*/
	float dm;		/* migration gather spatial sample int. */
	int im;			/* number of traces in migration gather */
	int *mtnz;		/* migrated trace data non zero smaples */
	char **dummyi;		/* index array that the trace contains zeros only */
	float fac;		/* velocity scale factor */
	int sphr;		/* spherical divergence flag */
	int imt;		/* mute time sample of trace */
	float tmp;
	int imoff;
	int **igtr=NULL;
	int nigtr;
	int n2;
	int n3;

	int verbose;
	
	/* phase shift filter stuff */
        float power;            /* power of i omega applied to data     */
        float amp;              /* amplitude associated with the power  */
        float arg;              /* argument of power                    */
        float phasefac;         /* phase factor                         */
        float phase;            /* phase shift = phasefac*PI            */
        complex exparg;         /* cexp(I arg)                          */
        register float *rt;     /* real trace                           */
        register complex *ct;   /* complex transformed trace            */
        complex *filt;          /* complex power                        */
        float omega;            /* circular frequency                   */
        float domega;           /* circular frequency spacing (from dt) */
        float sign;             /* sign in front of i*omega default -1  */
        int nfft;               /* number of points in nfft             */
        int nf;                 /* number of frequencies (incl Nyq)     */
        float onfft;            /* 1 / nfft                             */
        size_t nzeros;          /* number of padded zeroes in bytes     */
	
	initargs(argc, argv);
   	requestdoc(1);
	
        MUSTGETPARSTRING("fs",&fs);
        MUSTGETPARSTRING("fv",&fv);
        MUSTGETPARINT("n2",&n2);
        MUSTGETPARINT("n3",&n3);
        MUSTGETPARFLOAT("d2",&d2);
        MUSTGETPARFLOAT("d3",&d3);
	
	if (!getparfloat("dm", &dm))	dm=(d2+d3)/2.0;
	
	/* open datafile */
        fps = efopen(fs,"r");
	fpv = efopen(fv,"r");
	
	/* Open tmpfile for headers */
	headerfp = etmpfile();

	/* get information from the first data trace */
	ntr = fgettra(fps,&tr,0);
	if(n2*n3!=ntr) err(" Number of traces in file %d not equal to n2*n3 %d \n",
			     ntr,n2*n3);
	ns=tr.ns;
	if (!getparfloat("dt", &dt))	dt = ((float) tr.dt)/1000000.0;
	if (!dt) {
		dt = .002;
		warn("dt not set, assumed to be .002");
	}

	/* get information from the first velocity trace */
	ntrv = fgettra(fpv,&trv,0);
	if(ntrv!=ntr) err(" Number of traces in velocity file %d differ from %d \n",
			     ntrv,ntr);
	nsv=trv.ns;
	if (!getparfloat("dtv", &dtv))	dtv = ((float) trv.dt)/1000000.0;
	if (!dtv) {
		dtv = .002;
		warn("dtv not set, assumed to be .002 for velocity");
	}
	
	if (!getparfloat("fac", &fac))	fac=2.0;
	if (!getparint("verbose", &verbose))	verbose=0;
	if (!getparint("sphr", &sphr))	sphr=0;
	
	if (!getparfloat("apr", &apr))	apr=75;
	apr*=3.141592653/180;

	/* allocate arrays */
	data = bmalloc(sizeof(float),ns,ntr);
	vel = bmalloc(sizeof(float),nsv,ntr);
	velf = ealloc1float(nsv); 
	velfi = ealloc1float(ns);
	migt = ealloc1float(ns);
	vdt = ealloc1float(nsv);
	ddt = ealloc1float(ns);
	ap = ealloc1float(ns);
	mtnz = ealloc1int(ns);
	dummyi = (char **) ealloc2(n2,n3,sizeof(char));
	
	/* Times to do interpolation of velocity from sparse sampling */
	/* to fine sampling of the data */
	{ register int it;
		for(it=0;it<nsv;it++) vdt[it]=it*dtv;
		for(it=0;it<ns;it++)  ddt[it]=it*dt;
	}
	
	/* Read traces into data */
        /* Store headers in tmpfile */
        ntr=0;
	erewind(fps);
	erewind(fpv);
		
	{ register int i2,i3;
	for(i3=0;i3<n3;i3++) 
		for(i2=0;i2<n2;i2++) {
			fgettr(fps,&tr);
			fgettr(fpv,&trv);
			if(tr.trid > 2) dummyi[i3][i2]=1;
			else dummyi[i3][i2]=0;	
			efwrite(&tr, 1, HDRBYTES, headerfp);
		 	bmwrite(data,1,0,i3*n2+i2,ns,tr.data);
		 	bmwrite(vel,1,0,i3*n2+i2,nsv,trv.data);
		}
	erewind(headerfp);

	/* set up the phase filter */
	power = 1.0;sign = 1.0;phasefac = 0.5;
	phase = phasefac * PI;
         
	/* Set up for fft */
        nfft = npfaro(ns, LOOKFAC * ns);
        if (nfft >= SU_NFLTS || nfft >= PFA_MAX)
                err("Padded nt=%d -- too big", nfft);

        nf = nfft/2 + 1;
        onfft = 1.0 / nfft;
        nzeros = (nfft - ns) * FSIZE;
        domega = TWOPI * onfft / dt;
        
	/* Allocate fft arrays */
        rt   = ealloc1float(nfft);
        ct   = ealloc1complex(nf);
        filt = ealloc1complex(nf);
        
	/* Set up args for complex power evaluation */
        arg = sign * PIBY2 * power + phase;
        exparg = cexp(crmul(I, arg));
        {       
		register int i;
                for (i = 0 ; i < nf; ++i) {

                        omega = i * domega;
		
		        /* kludge to handle omega=0 case for power < 0 */
                        if (power < 0 && i == 0) omega = FLT_MAX;

                        /* calculate filter */
                        amp = pow(omega, power) * onfft;
			filt[i] = crmul(exparg, amp);
                }
        }
	
	/* set up constants for migration */ 
	if(verbose) fprintf(stderr," Setting up constants....\n");
	r=0;
	for(i3=0;i3<n3;i3++) 
	    for(i2=0;i2<n2;i2++) {
		if(dummyi[i3][i2] < 1) {
			
			/* get the velocity function */
			bmread(vel,1,0,i3*n2+i2,nsv,velf);
			
			/* linear interpolation from nsv to ns values */  
			intlin(nsv,vdt,velf,velf[0],velf[nsv-1],ns,ddt,velfi);
			
			/* Apply scale factor to velocity */
			{ register int it;
				for(it=0;it<ns;it++) velfi[it] *=fac;
			}
			
			/* compute maximum radius from apperture and velocity */
			{ register int it;
				for(it=0;it<ns;it++) 
				ap[it] = ddt[it]*velfi[it]*tan(apr)/2.0;
			}
			tmp = ap[isamax(ns,ap,1)];
			if(tmp>r) r=tmp;
		}
	}
	r=MIN(r,sqrt(SQR((n2-1)*d2)+SQR((n3-1)*d3)));
	ir2 =  (int)(2*r/d2)+1;
	ir3 =  (int)(2*r/d3)+1;
	im = (int)(r/dm)+1;
		
	/*  allocate migration gather */
	mgd = ealloc2float(ns,im);
	mgdnz = ealloc2int(ns,im);
	apt = ealloc1int(im);
	/* set up the stencil for selecting traces */
	igtr = ealloc2int(ir2*ir3,2);
	stncl(r, d2, d3,igtr,&nigtr);
	
	if(verbose) {
		fprintf(stderr," Maximum radius %f\n",r);
		fprintf(stderr," Maximum offset %f\n",
			sqrt(SQR((n2-1)*d2)+SQR((n3-1)*d3)));
	}

	/* main processing loop */
	for(i3=0;i3<n3;i3++) 
	    for(i2=0;i2<n2;i2++) {
		memset( (void *) tr.data, (int) '\0',ns*FSIZE);
		if(dummyi[i3][i2] < 1) {
			memset( (void *) mgd[0], (int) '\0',ns*im*FSIZE);
			memset( (void *) mgdnz[0], (int) '\0',ns*im*ISIZE);
			/* get the velocity function */
			bmread(vel,1,0,i3*n2+i2,nsv,velf);
		
			/* linear interpolation from nsv to ns values */  
			intlin(nsv,vdt,velf,velf[0],velf[nsv-1],ns,ddt,velfi);
		
			/* Apply scale factor to velocity */
			{ register int it;
				for(it=0;it<ns;it++) velfi[it] *=fac;
			}

			/* create the migration gather */
			{ register int itr,ist2,ist3;
				for(itr=0;itr<nigtr;itr++) {
					ist2=i2+igtr[0][itr];
					ist3=i3+igtr[1][itr];
					if(ist2 >= 0 && ist2 <n2) 
						if(ist3 >= 0 && ist3 <n3) {
							if(dummyi[ist3][ist2] <1) {
								imoff = (int) ( 
								sqrt(SQR(igtr[0][itr]*d2)
							     	    +SQR(igtr[1][itr]*d3))/dm+0.5);
								bmread(data,1,0,ist3*n2+ist2,ns,tr.data);
								imoff=MIN(imoff,im-1);
								{ register int it;									
									/* get the mute time for this 
									  offset, apperture and velocity */
									xindex(ns,ap,imoff*dm,&imt);
									for(it=imt;it<ns;it++)
										if(tr.data[it]!=0) {
											mgd[imoff][it]+=tr.data[it];
											mgdnz[imoff][it]+=1;
									}	
								}
							}
						}
				}
			}

			/* normalize the gather */
				{ register int ix,it;
				for(ix=0;ix<im;ix++)
					for(it=0;it<ns;it++) 
						if(mgdnz[ix][it] > 1) mgd[ix][it] /=(float) mgdnz[ix][it];
			}
			memset( (void *) tr.data, (int) '\0',ns*FSIZE);
			memset( (void *) mtnz, (int) '\0',ns*ISIZE);
		
			/* do a knmo */
			{ register int ix,it;
				for(ix=0;ix<im;ix++) {
					/* get the mute time for this 
					offset, apperture and velocity */
					xindex(ns,ap,ix*dm,&imt);
					knmo(mgd[ix],migt,ns,velfi,0,ix*dm,dt,imt,sphr);
					/* stack the gather */
						for(it=0;it<ns;it++) { 
						if(migt[it]!=0.0) { 
								tr.data[it] += migt[it];
								mtnz[it]++;
						}
/*						tr.data[it] += mgd[ix][it]; */
					}
				}

			}
			{ register int it;
				for(it=0;it<ns;it++) 
					if(mtnz[it]>1) tr.data[it] /=(float)mtnz[it];
			}
		
			/*Do the phase filtering before the trace is released*/
                	/* Load trace into rt (zero-padded) */
               		memcpy( (void *) rt, (const void *) tr.data, ns*FSIZE);
               		memset((void *) (rt + ns), (int) '\0', nzeros);

         		pfarc(1, nfft, rt, ct);
        		{ register int i;
        			for (i = 0; i < nf; ++i)  ct[i] = cmul(ct[i], filt[i]);
        		}
         		pfacr(-1, nfft, ct, rt);
     			memcpy( (void *) tr.data, (const void *) rt, ns*FSIZE);
			
		} /* end of dummy if */
		/* spit out the gather */
		efread(&tr, 1, HDRBYTES, headerfp);
		puttr(&tr);
		if(verbose) fprintf(stderr," %d %d\n",i2,i3);
	    }   /* end of i2 loop */
	}	/* end of i3 loop */
	/* This should be the last thing */
	efclose(headerfp);
	/* Free memory */
	free2int(igtr);
	free2float(mgd);
	free2int(mgdnz);
	free1int(apt);
	bmfree(data);
	bmfree(vel);
	free1float(velfi);
	free1float(velf);
	free1float(ddt);
	free1float(vdt);
	free1float(ap);
	free1int(mtnz);
	free1float(migt);
	free1float(rt);
	free1complex(ct);
	free1complex(filt);
	free2((void **) dummyi);
	
	return EXIT_SUCCESS;
}