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



NNAAMMEE
       ii..ttaappee..mmssss  - An imagery function that extracts Multispec-
       tral 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  Scan-
       ner (MSS) imagery data from tape.


       This  program  must  be	run in a LOCATION_NAME with a x,y
       coordinate system (i.e., a coordinate system with  projec-
       tion  0).   For	further  information regarding this LOCA-
       TION_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 informa-
       tion 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 Identifica-
       tion.  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 EXTRACTION 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 specified 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 dis-
       played 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 coor-
       dinates will display negative numbers in  the  north-south
       direction,  but	ignoring the negative 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)
