i.tape.mss(1)		      Grass User's Manual		 i.tape.mss(1)



NNAAMMEE
       ii..ttaappee..mmssss   -  An imagery function that extracts Multispectral Scanner
       (MSS) imagery data from half-inch tape.
       _(_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
       ii..ttaappee..mmssss

DDEESSCCRRIIPPTTIIOONN
       _i_._t_a_p_e_._m_s_s is a	program  that  extracts  Multispectral	Scanner  (MSS)
       imagery data from tape.


       This  program must be run in a LOCATION_NAME with a x,y coordinate sys-
       tem (i.e., a coordinate system with projection 0).  For further	infor-
       mation  regarding  this	LOCATION_NAME  refer  to  the manual entry for
       _i_m_a_g_e_r_y.


       The first prompt in _i_._t_a_p_e_._m_s_s asks the user for the tape device  name.
       This  is sometimes  /dev/rmt0 (for a half-inch tape with a tape density
       of 1600), but this varies with each machine.


       The next prompt is:

       Please mount and load tape, then hit RETURN


IIMMAAGGEE IIDDEENNTTIIFFIICCAATTIIOONN MMEENNUU
       The first menu in the program asks the user for information  about  the
       data.



	   please enter the following information

	Tape Identification:				 __

	Image Description:				 __

	Title for the Extracted Raster (Cell) Files:	 __

	AFTER COMPLETING ALL ANSWERS, HIT <ESC> TO CONTINUE
		      (OR <Ctrl-C> TO CANCEL)


       This  program  automatically enters the scene ID number and the date of
       the image into the field for Tape Identification.  The sun  angles  are
       automatically entered into the field for Image Description.


       The second menu is:

		       MSS TAPE EXTRACTION
       please select the desired tape window (geographic
       region definition) to extract

		    first row: _______(1-2984)
		    last row: _______(1-2984)

		    first col: _______(1-3548)
		    last col: _______(1-3548)


       AFTER COMPLETING ALL ANSWERS, HIT <ESC> TO CONTINUE
		     (OR <Ctrl-C> TO CANCEL)


       The  numbers in parentheses are the total number of rows and columns on
       the tape including filler (zeros).   This  information  and  additional
       information   can  also	be  obtained  by  running  the	GRASS  program
       _i_._t_a_p_e_._m_s_s_._h which reads the header information on an  MSS  tape.   Any
       subset  of the image on tape may be extracted.  For a discussion of row
       and column extraction see the subheading TITLEd ROW AND COLUMN  EXTRAC-
       TION below.


       The next menu is:

       please make an x by the bands you want extracted

			     _____ 1
			     _____ 2
			     _____ 3
			     _____ 4

       AFTER COMPLETING ALL ANSWERS, HIT <ESC> TO CONTINUE
		     (OR <Ctrl-C> TO CANCEL)

       MSS imagery has 4 bands, but the user may want to extract only a subset
       of these bands.	See the subheading in this entry TITLEd ROW AND COLUMN
       EXTRACTION.


       The  user then is asked to enter the prefix/group for the band files to
       be created.  This name will  precede  each  band  file  extracted  into
       GRASS.	For  example, if three bands are extracted the following three
       (raster) band files will result:


       _p_r_e_f_i_x_n_a_m_e_._1
       _p_r_e_f_i_x_n_a_m_e_._2
       _p_r_e_f_i_x_n_a_m_e_._3


       Whatever _p_r_e_f_i_x_n_a_m_e is specified will  also  automatically  become  the
       name  for the imagery group file being created.	Each image (i.e., each
       run of _i_._t_a_p_e_._m_s_s) should be given a unique prefix/group name.


       The extraction process will begin by first skipping the number of spec-
       ified  files, advancing to the starting row, and then reading the tape.
       The percent completion of the extraction is displayed on the screen. If
       more  than  one	tape  is required to store the image, the program will
       pause and inform the user to mount the next tape.


       The extracted (raster) band files will be listed as raster  map	layers
       available  in  the  current MAPSET and may be displayed using the GRASS
       commands _d_._d_i_s_p_l_a_y, _d_._r_a_s_t or _i_._p_o_i_n_t_s.

NNOOTTEESS
       After extracting an image from tape, the geographic  region  definition
       in  the	x,y  coordinate  LOCATION_NAME	will  be  set  based  upon the
       extracted rows and columns from the tape.  The relationship between the
       image  rows and columns and the geographic coordinates of the region is
       discussed in the manual entry for _i_m_a_g_e_r_y.


       This program is interactive and requires no command line arguments.

RROOWW AANNDD CCOOLLUUMMNN EEXXTTRRAACCTTIIOONN
       The display options in GRASS allow the user to locate rows and  columns
       on  the	digital image.	If enough disk space is available, one band of
       an entire image, or one band of a portion of an image known to  contain
       the area of interest, can be extracted and displayed.  The _m_e_a_s_u_r_e_m_e_n_t_s
       option in _d_._d_i_s_p_l_a_y, or _d_._w_h_e_r_e (following the use of _d_._r_a_s_t) will echo
       x  and  y  coordinates  to the screen.  (These coordinates will display
       negative numbers in the north-south direction, but ignoring  the  nega-
       tive sign will yield the row number.)  See the _i_m_a_g_e_r_y manual entry for
       further explanation.


       If a photograph of the digital image is available, the rows and columns
       to  be  extracted  can be determined from it by associating inches with
       the total number of known rows and columns in the scene.  For  example,
       if the total length of the photograph is 12 inches, the total number of
       rows on the tape is 2000, and the  northwest  corner  of  the  area  of
       interest begins 2 inches from the top of the photo, then:

	    12" / 2000 rows = 2" / x rows
	    x = 333.333

       The  northwest  corner  of the area of interest starts at row 333.  The
       starting row, ending row, starting column, and  ending  column  can  be
       calculated in this manner.

SSEEEE AALLSSOO
       _G_R_A_S_S _T_u_t_o_r_i_a_l_: _I_m_a_g_e _P_r_o _c_e_s_s_i_n_g


       _d_._d_i_s_p_l_a_y,    _d_._r_a_s_t,   _d_._w_h_e_r_e,   _i_._g_r_o_u_p,   _i_._p_o_i_n_t_s,	 _i_._t_a_p_e_._m_s_s_._h,
       _i_._t_a_p_e_._o_t_h_e_r, _i_._t_a_p_e_._t_m, _i_m_a_g_e_r_y

AAUUTTHHOORR
       Michael Shapiro, U.S.Army Construction Engineering Research Laboratory

       _L_a_s_t _c_h_a_n_g_e_d_: _$_D_a_t_e_: _2_0_0_2_/_0_1_/_2_5 _0_5_:_4_5_:_3_3 _$



GRASS 5.0							 i.tape.mss(1)
