gridhd.h

seismic software,very useful

/* gridhd.h - include file for grid header
 *
 * Author: zhiming li
 */ 

#ifndef GRIDHD_H
#define GRIDHD_H

#define	GHDRBYTES	100	/* Bytes in the grid header */
#define NGHDRS		25	/* number of variables in grid header */

typedef struct {	/* grid header */

	float scale;	/* scale to be applied to all the variables below */
			/* (typical value = 0.000001)			*/
			/* to compute their actual values 		*/ 
			/* e.g., value(n1) = ghdr.n1 / ghdr.scale	*/

	float dtype;	/* grid data type */
			/* =1.*scale	-- 1-byte char numbers */
			/* =2.*scale	-- 2-byte short (integer*2) numbers */
			/* =4.*scale	-- 4-byte floating-point numbers    */
			/* =8.*scale	-- 8-byte complex numbers	    */

	float n1;	/* number of samples of the 1st axis of the grid */  

	float n2;	/* number of samples of the 2nd axis of the grid */  

	float n3;	/* number of samples of the 3rd axis of the grid */  

	float n4;	/* number of samples of the 4th axis of the grid */  

	float n5;	/* number of samples of the 5th axis of the grid */  

	float d1;	/* coordinate increment of the 1st axis of the grid */

	float d2;	/* coordinate increment of the 2nd axis of the grid */

	float d3;	/* coordinate increment of the 3rd axis of the grid */

	float d4;	/* coordinate increment of the 4th axis of the grid */

	float d5;	/* coordinate increment of the 5th axis of the grid */

	float o1;	/* starting coordinate of the 1st axis of the grid */

	float o2;	/* starting coordinate of the 2nd axis of the grid */

	float o3;	/* starting coordinate of the 3rd axis of the grid */

	float o4;	/* starting coordinate of the 4th axis of the grid */

	float o5;	/* starting coordinate of the 5th axis of the grid */

	float dcdp2;	/* cdp number increment along the 2nd axis 	*/ 

	float dline3;	/* line number increment along the 3rd axis 	*/ 

	float ocdp2;	/* cdp number at the begin of the 2nd axis	*/ 

	float oline3;	/* line number at the begin of the 3nd axis	*/ 
	
	float gmin;	/* minimum data value of the grid 		*/ 
			/* for dtype=1,2,4	may be negative 	*/ 
			/* for dtype=8		minimum absolute value (norm)*/ 

	float gmax;	/* maximum data value of the grid 		*/ 
			/* for dtype=1,2,4	may be negative 	*/ 
			/* for dtype=8		maximum absolute value (norm)*/ 

	float orient;   /* orientation of grid axes */
			/* 0= not defined;	*/
			/* 1= 1st: time/depth; 2nd: inline; 3rd: crossline */
			/* 2= 1st: inline; 2nd: time/depth; 3rd: crossline */
			/* 3= 1st: inline; 2nd: crossline; 3rd: time/depth */
	float gtype;	/* grid type	*/
			/* 0=not defined */
			/* 1=time-rms velocity */
			/* 2=time-average velocity */
			/* 3=time-interval velocity */
			/* 4=depth   */
} gridheader, ghed;


#endif