photo.rectify(1)       Grass User's Manual	 photo.rectify(1)



_T_h_i_s  _i_s  _n_o_t  _a  _c_o_m_m_a_n_d _i_n _i_t_s_e_l_f_, _b_u_t _a_n _o_p_t_i_o_n _o_f _t_h_e _c_o_m_m_a_n_d
_i_._o_r_t_h_o_._p_h_o_t_o .

NNAAMMEE
       _p_h_o_t_o_._r_e_c_t_i_f_y - An  imagery  function  that  rectifies  an
       image  by  computing  a coordinate transformation for each
       cell in the image using parameters computed by  the  GRASS
       programs _p_h_o_t_o_._2_i_m_a_g_e and _p_h_o_t_o_._2_t_a_r_g_e_t.
       _(_G_R_A_S_S _I_m_a_g_e _P_r_o_c_e_s_s_i_n_g _P_r_o_g_r_a_m_)

SSYYNNOOPPSSIISS
       Selected from _i_._o_r_t_h_o_._p_h_o_t_o


DDEESSCCRRIIPPTTIIOONN
       _p_h_o_t_o_._r_e_c_t_i_f_y  rectifies  an  image  by using the image to
       photo  coordinate   transformation   matrix   created   by
       photo.2image  and  the rectification parameters created by
       photo.2target. Rectification is the process by  which  the
       geometry  of an image is made planimetric.  This is accom-
       plished by mapping an image from one coordinate system  to
       another.  In  photo.rectify  the  parameters  computed  by
       photo.2image and photo.2target are used	in  equations  to
       convert	x,y image coordinates to standard map coordinates
       for each pixel in the image.  The result is an image  with
       a  standard  map coordinate system, compensated for relief
       distortions and photographic tilt. Upon completion of  the
       program	the  rectified image is deposited in a previously
       targeted GRASS LOCATION.

	You are asked to select the file(s)  within  the  imagery
       group to be rectified:

	Please	select the file(s) to rectify by naming an output
       file


       gs13.1 in PERMANENT   gs13.orect...  gs14.1  in	PERMANENT
       .............   (enter  list  by any name to get a list of
       existing cell files) AFTER COMPLETING ALL ANSWERS, HIT  TO
       CONTINUE (OR  TO CANCEL)





       More  than one file may be rectified at a time.	Each file
       should have a unique output file name.


       The next prompt asks you to select one of two windows:



	     Please select one of the following options
	     1.   Use the current window in the target location
	     2.   Determine the smallest window which covers  the
       image
	     >


	_p_h_o_t_o_._r_e_c_t_i_f_y will only rectify that portion of the image
       that occurs within the chosen window.  Only  that  portion
       will  be relocated in the target database. It is therefore
       important to check the current window in the target  LOCA-
       TION if choice number one is selected.


       _p_h_o_t_o_._r_e_c_t_i_f_y will run in the background and notify you by
       mail when it is finished. The process may take an hour  or
       more depending on the size of the image, the number files,
       and the size and resolution of the selected window.

	The rectified image will be located in the  target  LOCA-
       TION  when the program is completed. The original unrecti-
       fied files are not modified or removed.

SSEEEE AALLSSOO
       _i_._o_r_t_h_o_._p_h_o_t_o

       _p_h_o_t_o_._c_a_m_e_r_a

       _p_h_o_t_o_._2_i_m_a_g_e

       _p_h_o_t_o_._2_t_a_r_g_e_t

       _p_h_o_t_o_._i_n_i_t


AAUUTTHHOORR
       Mike Baba,  DBA Systems, Inc.

       Updated rectification  and  elevation  map  to  FP  1/2002
       Markus Neteler

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_2_/_2_8 _2_3_:_4_6_:_5_7 _$



GRASS 5.0					 photo.rectify(1)
