emeta.h

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/*
 *  Name:   emeta.h
 *
 *  Purpose:
 *  Include file defining the enhanced metadata structure that is used to capture the
 *  scene viewing geometry information needed to calculate per-pixel view angles. This
 *      information includes linkages between L1T line/sample pixel coordinates and the
 *  corresponding time of observation, so it can also be used to generate per-pixel
 *  sun angles.
 */
#ifndef _EMETA_H_
#define _EMETA_H_
 
/* Defines the maximum number of normal bands present on any of the supported
   satellites.  Note that this should only be used if absolutely necessary.
   It is preferred that arrays be sized dynamically. */
#define IAS_MAX_NBANDS 11
 
/* Defines the maximum number of SCAs present on any of the supported 
   sensors.   Note that this should only be used if absolutely necessary.
   It is preferred that arrays be sized dynamically. */
#define IAS_MAX_NSCAS 14
 
#include "ias_const.h"
#include "ias_structures.h"         /* IAS_VECTOR and IAS_CORNERS                */
 
#define     NUM_RPC_COEF    5       /* Number of image RPC coefficents in model  */
#define     ANG_RPC_COEF    10      /* Number of angle RPC coefficents in model  */
 
typedef struct EMETA_IMG_RPC
{
    int     sca_num;            /* Number of current SCA                     */
    double  mean_l1r[2];            /* L1R mean line, sample offset              */
    double  mean_l1t[2];            /* L1T mean line, sample offset              */
    double  mean_hgt;           /* Mean height offset                        */
    double  line_num[NUM_RPC_COEF];     /* L1R line RPC numerator coefficients       */
    double  line_den[NUM_RPC_COEF-1];   /* L1R line RPC denominator coefficients     */
    double  samp_num[NUM_RPC_COEF];     /* L1R sample RPC numerator coefficients     */
    double  samp_den[NUM_RPC_COEF-1];   /* L1R sample RPC denominator coefficients   */
} EMETA_IMG_RPC;
 
typedef struct EMETA_ANG_RPC
{
    double  mean_l1t[2];            /* L1T mean line, sample offset              */
    double  mean_hgt;           /* Mean height offset                        */
    double  mean_l1r[2];            /* L1R mean line, sample offset              */
    double  mean_vec[3];            /* Mean vector component offsets             */
    double  x_num[ANG_RPC_COEF];        /* X axis RPC numerator coefficients         */
    double  x_den[ANG_RPC_COEF-1];      /* X axis RPC denominator coefficients       */
    double  y_num[ANG_RPC_COEF];        /* Y axis RPC numerator coefficients         */
    double  y_den[ANG_RPC_COEF-1];      /* Y axis RPC denominator coefficients       */
    double  z_num[ANG_RPC_COEF];        /* Z axis RPC numerator coefficients         */
    double  z_den[ANG_RPC_COEF-1];      /* Z axis RPC denominator coefficients       */
} EMETA_ANG_RPC;
 
typedef struct EMETA_SCENE_PROJ
{
    /* ==== WGS84 ellipsoid parameters ====                                                  */
    double  wgs84_major_axis;       /* WGS 84 ellipsoid semi-major axis (meters) */
    double  wgs84_minor_axis;       /* WGS 84 ellipsoid semi-minor axis (meters) */
    /* ==== Projection parameters and info. ====                                             */
    char    units[IAS_UNITS_SIZE];      /* Projection units string                   */
    int     code;               /* Projection code for the output space image.
                           Values for this field are defined in the
                           "gctp.h" include file.                    */
    char    datum[IAS_DATUM_SIZE];      /* Projection datum string                   */
    //int       spheroid;           /* Projection spheroid code                  */
    int     zone;               /* Projection zone code for UTM or
                           State Plane projections.                  */
    double  projprms[IAS_PROJ_PARAM_SIZE];
        /* Array of 15 projection coefficients as required by the projection 
           transformation package.  Refer to the projection package documentation 
           for a description of each field for a given projection.                   */
    /* ==== Grid corners. ====                                                               */
    struct  IAS_CORNERS corners;        /* Projection coordinates of the resulting 
                           output image's four corners.              */
} EMETA_SCENE_PROJ;
 
typedef struct EMETA_BAND
{
    int         band;           /* User band number                          */
    int         nsca;               /* Number of SCAs in the band                */
    int         l1t_lines;      /* Number of lines in the L1T image.         */
    int         l1t_samps;      /* Number of samples in the L1T image.       */
    int         l1r_lines;      /* Number of lines in the L1R image.         */
    int         l1r_samps;      /* Number of samples in one L1R SCA.         */
    double      pixsize;        /* Projection distance per pixel in meters.  */
    double      img_start_time;     /* Image start time, offset in seconds from
                           ephemeris epoch                           */
    double      line_time;      /* L1R line time increment in seconds        */
    EMETA_ANG_RPC   sat;            /* Satellite view vector RPC structure       */
    EMETA_ANG_RPC   sun;            /* Solar illumination vector RPC structure   */
    EMETA_IMG_RPC   rpc[IAS_MAX_NSCAS]; /* Per SCA RPC coefficient structures        */
} EMETA_BAND;
 
typedef struct EMETA_EPHEM
{
    double  eph_sample_time;        /* Sample time from ephemeris epoch          */
    IAS_VECTOR  ecef_position;          /* ECEF positions                            */
} EMETA_EPHEM;
 
typedef struct EMETA
{
    //int           wrs_path;       /* WRS path number (target)                  */
    //int           wrs_row;        /* WRS row number (target)                   */
    EMETA_SCENE_PROJ    projection;     /* Ground reference for this L1T scene       */
    int         num_band;       /* Number of bands in the metadata structure */
    EMETA_BAND      band_emeta[IAS_MAX_NBANDS]; /* Enhanced metadata for each band   */
    double      eph_epoch_time[3];  /* UTC time ([0]=year,
                                     [1]=day of year,
                                     [2]=second of day )
                           of ephemeris epoch                        */
    int         ephem_count;        /* Number of ephemeris samples               */
    EMETA_EPHEM     *ephemeris;     /* Ephemeris data for scene                  */
    EMETA_EPHEM     *sunvector;     /* ECEF solar vectors for scene              */
} EMETA;
 
int emeta_allocate_ephemeris(
    EMETA   *emeta,             /* Enhanced metadata structure               */
    int     nephem );           /* Number of ephemeirs points required       */
 
void emeta_free_ephemeris(
    EMETA   *emeta );           /* Enhanced metadata structure               */
 
#endif