WPC 
      2       B   V   o          Z     #| S          0pt (HP Roman 8) (Port) (FW) } 2 ] : , ,    ] 	[ 
    P fQ  
P21/01/96 06:22            Practical Lessons using Marine and Coastal Image Data                                              XX  XX             X `  TTTTT|LxXxXxXxX@0@0@0@0`````````LT\``L `h`TTT|L|L|L|L\xXxXxXxXTTTTTT``@ @ @0@   L \p0p0p0p0p0``````  DDD`D`D`D`Dt8t8t8``````xL|L|L|L  \p0`D`Dt8LL\``  dh XX8TXXXX X@HX    h^                                  8d                                                        HP LaserJet Series II (Additional)   HLSEIIDU.PRS ] 	[ 
    P fQ     0Z
P 2       9     9     I  	      #| S          21/01/96 06:22            Practical Lessons using Marine and Coastal Image Data                                               2 .                   Z      "  m^4HHl̰4TTl4H4<llllllllll<<lԤP`̤xԨH<Hl4lt`xlHhx<<p<xtxxTTHxd```llll ll  ll             l t  lllll䨘`llllP<P<P<P<xttttxxxx`lxtt` xxlll````xllllhhhhhhxxP P P<P   ` p<<<<<xxxxtt  TTTxTxTxTxTHHHxxxxxxԔ````  x<xTxTH``xtx    llHlllll lPXl    ^                                  Hx                                                         "  m^,8<X,DDX,8,0XXXXXXXXXX00Tx|xl@Lph`t|808X,T\L\X8T`00\0```\DD8`PxLLLXXXX XX  XX             X `  TTTTT|LxXxXxXxX@0@0@0@0`````````LT\``L `h`TTT|L|L|L|L\xXxXxXxXTTTTTT``@ @ @0@   L \p0p0p0p0p0``````  DDD`D`D`D`Dt8t8t8``````xL|L|L|L  \p0`D`Dt8LL\``  dh XX8TXXXX X@HX    h^                                  8d                                                        HP LaserJet Series II (Additional)   HLSEIIDU.PRS ] 	[ 
    P fQ     0Z
P 2 
      `    f  	  
          chapter                                                                      S  e    #  ] 	[ 
    P fQ   
P# 
    
  t                g H    #  H 	`>	    xi fQ  ԩX# Marine and Coastal Image Data Module 5:t  k              7   } S    `(#7 #  H 	`>	    xi fQ  ԩX# Practical Lessons: 8k #  ] 	[ 
    P fQ   
P#  "  m^,4<X|,DDX(8,0XXXXXXXXXX00Pxt|xh@@xtht`ptthxL4HX,\XL\L4L\,,X,\\XX8D0`PtHHDXXXX XX  XX             X `  x\x\x\x\x\|LxLxLxLxL@,@,@,@,\\\\\````hHx\\\\hH \hXx\x\x\|L|L|L|L\xLxLxLxLLLLLLL\\@ @ @,@   @ xXt,t,t,t,t,\\\\\\  t8t8t8`D`D`D`Dp0p0p0``````thHxDxDxD  \t,\t8`Dp0hHhH\\`  dh XX4PHHXX XDDX    h^                                  8d                                                         "  m^,8<X,DDX,8,0XXXXXXXXXX00Tx|xl@Lph`t|808X,l`dpdXtt0<h\ltTtlL\tllldXXXX XX  XX             X `  TTTTT|LxXxXxXxX@0@0@0@0`````````LT\``L `h`TTT|L|L|L|L\xXxXxXxXTTTTTT``@ @ @0@   L \p0p0p0p0p0``````  DDD`D`D`D`Dt8t8t8``````xL|L|L|L  \p0`D`Dt8LL\``  dh XX8TXXXX X@HX    h^                                  8d                                                         2           ,         "  m^ ((`@th 00@h (  @@@@@@@@@@$$hhh<|`TXdXLdh,8\Pt`dLd`DPh`|``X( (|@ <D8H<(<D$$@$dDDHH00(D8T488@@@h@ @@  @@             @ H  `<`<`<`<`<`X8X<X<X<X<,$,$,$,$`DdDdDdDdDhDhDhDhD`8`<dHdDdD`8 DLH`<`<`<X8X8X8X8dHX<X<X<X<d<d<d<d<d<d<hDhD, , ,$,   8 \@P$P$P$P$P$`D`D`D`DdDdD  `0`0`0D0D0D0D0P(P(P(hDhDhDhDhDhD|T`8X8X8X8  dHP$`D`0D0P(`8`8dHdDhD   H @@(<@@@@ @,4dd@    Ld^hh                                  (D                                                        \ "  m^ $(`@tX 00@h(  @@@@@@@@@@$ hhh8|TPX\TLd`,0TTp\`H`PDL\PpTLT8(4|@@@8D8$4@  < d@@@@(0$D8T400@@@h@ @@  @@             @ @  T@T@T@T@T@x\X8T8T8T8T8, , , , \@`@`@`@`@\D\D\D\DL0T@\D`@`@L0 DH@T@T@T@X8X8X8X8\DT8T8T8T8d4d4d4d4d4d4`@`@, , , ,   0 T<T T T T T \@\@\@\@`@`@  P(P(P(D0D0D0D0L$L$L$\D\D\D\D\D\DpTL0T0T0T0  \DT \@P(D0L$L0L0\D`@\D   H @@$844@@ @00dd@    Ld^hh                                  (D                                                        \ "  m^$,0lHt$88Ht$0$$HHHHHHHHHH((tttDl`dpdXtt0<h\ltTtlL\tllld0$0H$DL<LD,DL$$H$tLLLL840L@`<@<HHHtH HH  HH    H    H   H L  lDlDlDlDlDld<dDdDdDdD0$0$0$0$lLtLtLtLtLtLtLtLtLl@lDpLtLtLl@HLTLlDlDlDd<d<d<d<pLdDdDdDdDtDtDtDtDtDtDtLtL0 0 0$0   < hH\$\$\$HH\$lLlLlLlLtLtL  l8l8l8L4L4L4L4\0\0\0tLtLtLtLtLtL`l@d<d<d<  pL\$lLl8L4\0l@l@pLtLtLNH HT HH,DHHHHHH48ppHH HHTpH          H       H H             H                HmttHH    HH  HHHHH  HHHHHHHHHHHH     0P H         H                                            h              H "  m^,8<X,DDX,8,0XXXXXXXXXX00TptxthDXpl|dlt|ltL,LX,X\L\P8Td08\0dX\\LL<dPtTPLXXXX XX  XX             X `  pXpXpXpXpX|xLtPtPtPtPD0D0D0D0dXXXXddddlPpX\XXlP Xl\pXpXpXxLxLxLxL\tPtPtPtPTTTTTTddD D D0D   X \p0p0p0p0p0ddddXX  |L|L|LdLdLdLdLl<l<l<ddddddtlPtLtLtL  \p0d|LdLl<lPlP\Xd  dh XX8T\\XX XD@X    h^                                  8d                                                         2 Z  ,  )    U  ,  =     i   "  m^$,0lHpp$88Ht$0$$HHHHHHHHHH((tttD\\dh\Tll4HlXhpXpdPXh\d\\<(<H$HL<L@,DT,,L,|THLH<<0P@\D@<HHHtH HH  HH    H    H   H L  \H\H\H\H\Hdd<\@\@\@\@4,4,4,4,hTpHpHpHpHhPhPhPhP\@\HhLpHpH\@HHXL\H\H\Hd<d<d<d<hL\@\@\@\@lDlDlDlDlDlDlTlT4 4 4,4   H lLX,X,X,HHX,hThThThTpHpH  d<d<d<P<P<P<P<X0X0X0hPhPhPhPhPhP\\@\<\<\<  hLX,hTd<P<X0\@\@hLpHhPNH HT HH,DLLHHHH84ppHH HHTpH          H       H H             H                HmttHH    HH  HHHHH  HHHHHHHHHHHH     0T H         H                                            h              H "  m^ (,`@`` 00@h (  @@@@@@@@@@$$hhh<|PTX\PL``,<`Pt\`L`XHP\PtXPP4$4|@ @D8D8$<H $@ hH@DD44,H8P<88@@@h@ @@  @@             @ D  P@P@P@P@P@tXX8P8P8P8P8, , , , \H`@`@`@`@\H\H\H\HP8P@\D`@`@P8 @LDP@P@P@X8X8X8X8\DP8P8P8P8`<`<`<`<`<`<`H`H, , , ,   < `@P P P P P \H\H\H\H`@`@  X4X4X4H4H4H4H4P,P,P,\H\H\H\H\H\HtPP8P8P8P8  \DP \HX4H4P,P8P8\D`@\H   H @@(<@@@@ @00dd@    Ld^hh                                  (H                                                        \ "  m^$(0lHd$88Ht 0$(HHHHHHHHHH($ttt@d\dh`Xpl48`\|hlTl\LXh\|`T`<(<H$HH@L<(<L$$H$tLLHH04(L@`<88HHHtH HH  HH    H    H   H L  dHdHdHdHdHhd@`<`<`<`<4$4$4$4$hLlLlLlLlLhLhLhLhLT8dHhLlLlLT8HLTHdHdHdHd@d@d@d@hL`<`<`<`<p<p<p<p<p<p<lLlL4 4 4$4   8 `H\$\$\$HH\$hLhLhLhLlLlL  \0\0\0L4L4L4L4X(X(X(hLhLhLhLhLhL|`T8`8`8`8  hL\$hL\0L4X(T8T8hLlLhLNH HT HH(@<<HHHH88ppHH HHTpH          H       H H             H                HmttHH    HH  HHHHH  HHHHHHHHHHHH     0P H         H                                            h              HDutch Roman 10.50pt (HP Roman 8) (Port) (FW) Courier 10cpi Dutch Roman 7.50pt (HP Roman 8) (Port) (FW) Dutch Italic 7.50pt (HP Roman 8) (Port) (FW) Dutch Roman 8.50pt (HP Roman 8) (Port) (FW) Dutch Bold 10.50pt (HP Roman 8) (Port) (FW) Dutch Bold 8.50pt (HP Roman 8) (Port) (FW) Dutch Bold 7.50pt (HP Roman 8) (Port) (FW) Dutch Italic 8.50pt (HP Roman 8) (Port) (FW) Dutch Italic 10.50pt (HP Roman 8) (Port) (FW) Dutch Roman 16pt (HP Roman 8) (Port) (FW) Dutch Roman 13pt (HP Roman 8) (Port) (FW)  2 &  
     ^  :"     R   c  J  "  ^ D X X     D d d   @ X @ H           H H             ` t                X H X  D   t   T   H H  H      d d X  |  t x t                                                               t         ` H ` H ` H ` H                    x          x             t  t  t  t                           `   `   ` H `       t      H  H  H  H  H                  d  d  d  d  d  d  d  X  X  X               x  t  t  t        H    d  d  X  x  x                   X         d l              ^                                                                       X                                                                                                                   } 2 ] : , ,    ] 	[ 
    P fQ  
P	 ? x x x , -  x 6X   @ 8; X@Z # C *   , ;  /%iC 	[ 
    P fQ  wP[ " @ *   , g  i@ 	`>	    xi fQ  wXf ( K / $ ,   WK 	[ 
    P fQ  Pd~ 1 \ : , ,   N,\ ~>	    p fQ  
f ( K / $ ,   1K ~>	    p fQ  Z # A *   ,  cA ~>	    p fQ  wTg ' H / $ , B ԙH 	`>	    xi fQ  X\ 0 Y : , , o Y 	`>	    xi fQ  
XL K  Y D ,   	[ 
    P fQ   P } 2 ] : , ,   ] 	[ 
    P fQ  
P	 = s H 4 ,  qs 	[ 
    P fQ  P 2         &                                 E  r   #   4      &l9         	 IG=l: fl    I$  K K  : %$$$  % %%%?% %%% &? _-* &&񀑀&{&&&&&& ''''' ' ' (((G?F(GF(?(((( ())) )ဎ )񀎀*))))) ) S9) R9* ** + + +++ ?, ,,, , ?- - - ....//// / ?0 0++, ,,,12 2À π?222233င 3󀄀 4?33444444 5  ~5 ~ 5 } 5 |8 {9 {9{9 { : x  :w : w  : ?v  ; v  ;u ; u ; t<?t<t<t<t<t = s=?r=r=r = r ?! q !q ! _p ! o! o!

o?!
 
o" 
 8߀- " 
 1o  , " / 
 ' "  /  
  '"'߀   ~||  '" '     x  x   '" "      | x? & "? "    x x; % " ǀ%      x0x   ?% "
? À*     ? xpx  ? %"
  <    ~   px   % "
?  ?  ?  x   |  px    $ "
     ?x    <  xx   ?# 	#   ?  x     xx  #	#?   )x      xx  #	#?   À%x     px # 	# π?%|    px " 
# ??À%~  ?  x? "
#   ?       x? "
# > <? |   x x   "
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ŀ   	  ? ? 9
 	   ? ?G
 	     ÀF ?
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Y   ? 0р
?R     
 ?R     
 ?Q     	?Q  x  	?P    ?	?P  	? 
?O  ?  	 
??M   	 
?L     	?L   	?K  
?K   
   ?K /   ?K   7 ?K?  
 ?K?  
 L       ? M     
  L ?   L ?   L    |L ?  M  
 ?M. J . ߀K . ?A ?.A    .A #.  @ #.  ?@$.ǀ@$/
?@%/
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  ?#  ?%/	
 ?#  ?%/	
 " ?%/	 ?!  0 ?%/?	? !   %/	?    %/	? 
   &/	 ?	  &/

?    &/
 
??     ?&/	?  ?     ?&0	?    ?      &0	 ?  p      &0	 ?     ?'0	 
?g ?      ?'0	@
?   ?     
  '0	 ?  '     ?h 
 '0	 p?     p     '0	   ?     '0 		   ?? ?  ? ? (0 		 ??
?    
? (0
    
?+!
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  ?}  ;0
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  H2À  ?
   I< ?À  
  I; ?? 
  K; l?   K; ??? L$?  M$   S;   	  S; 
 	 T;  	 'ǀ,; 	 { À	 'À,C
 À	 '+C
 ~
(+;π
 
(+;?
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/,;	???
?.,;	?
),:?	?)?,:?	),:	À (-:	À?'-:	À?'?-:À?'?-: 
À'-: 
?'-;?
 
??'.;  ?
??V;   ?
?V<@    X<  Y<    Y<    	?(0< ?
 	?Y< 
 ?Y= ?Y= 	  ?Y3	 	 Y3	Y3Y3X&?X&X3X3X3?X3?X3X3 ?h3 h3 h3 h3X?X? W3
 V3À
 ?V3
 πR3
 Q3
? Q3
 Q3PK?PK PK OKOK?PK?ǀOKOK LK NK??NK/L?NLNLNLNL?NM?NM?NMMMM?;MMM-MMMMLMLMLMLMLMLMπLMLMK M?KMKMK3K3K3K3F3E3?EL?EL)3߀ ?E3 EL ELO pEL? EL  EL   Em  EmErE qEqEqEqEqFqF 3=F3=F߀=Fǀ=F=F=F=F3=F3=F3=F 3=F3=E3=E3=?E3=?E3=?E3<?E3; ?E38 E3 7  @E36 p ߃F36 ǀF363I37I37LkL kLjL jLkL kÀLkL kÀLkLkKk?Kk?Kk?Kk?K k?K kKkKlK ZK QÀKlÀKlǀK lÀK lKlJl?Jl?Jl?Jl?J l?J l?J lJlJlJ4π7J47J48J48ÀJ 48À-48ÀJ48ÀJ47ÀJ4?7ÀJ4?7J47J47J47ÀJ47ÀJ47J 47I47?I4?7?I47?I47?I48?ImI m?I 5ǀ7?I 57?I 57?I56?I5?6?I5?6I5?6?I 56?I56I56I56I56I66F6/E6,E6+ ? 16*  16% ?   E6?   ?D6?   D6?   D6   D6   D6 ?    D6     ?D6        D7     | >D7     > D7 &       D7 &       D7? &         D7?   x       |D7 &  x p   ? ? > <D7 &   0        D7	 `      ~  
  D7	       
    ?D7	       
>  ?  D7
  
?    ??E        ?E   ?   E7 pp  I7 
pp H7 pp ?H8
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0 H9㿀  H9!  H9! H9! 3< H9   H9 ? H9 	 ,9  ,9 ? I: I: 
I: 
 I: I:x  ?I:p !(:0 !(:    !(:    c!(:  _#ǀ(:  c:  ?c:
d:d: e:  e:  e: e: f:?i:i:i:i:i:i :i :i:i:i:i ;i! g;  ?f;  f;  f;`  GP G< G;e;e0
e1	e;e; d ;?d;d<d<d<d<d<?c<c<c<c<c<?c<?c=?c=?c=c =?c=c =c=?c=c=c=c=c> b>?b> b> a>  `>?  `>  _>  _> ?^' ^? ^?^?^?^?^?^?]?]? ]@ ?]@?]@?]@?]@]@]@]@?]A?]A?]A]A]A]A?]A?QA?]A?]B?]B?]B?]B?]B ?]B ?LC?L?CL?C?]C ]D ?]D ]D]D]D]D]E\E ?\ E\E\E [E ?[E[E[E ZF  ?ZF ?ZF?ZF?ZF?ZF?ZG ?Z GZGZGZGZGZH ZH?ZHZ#$ZIZIZI ZJ ZJOZJ ZKZK?ZK??ZKZKZL  [L
[L
[L
[L
[L
?[ [?[ D?[D?[ Dǀ
?[D?
?[D?
?[D
?[D?[E??[E??[E??[E???[E??[E?[E ?[E ?[E?[B?[B? ?[B?
[B?
[B ?[B ?[B  ?[B  ?[A ?[A ???[A ??[A ?[@  [@   [@ ? [@? 
[?8
[? |??
[/ ~?
[? 
Z?  ?Z? ?Z? ?Z? ?Z?  ?Z> ??ǀ?Z>
 ??Z>
 ?Z>|Z>xπ[>  [>  [> [>	 [>	[@[A[A[A[A?[A[3	?[3	?[3  	[3  ? \3   x À\3   p  À\3  p  À\3 ?  p ?À\4    0  @ ǀ
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\4        
\4 @      \4       À\3 
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 ?À\3        ??À?\3        À\4       Àj5     j5    À]6 ?À]?	 ?]C? ???\C? ??\C? ?\C?\C? [C [C[C
 [CÀ
 ?ZC
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??ZD??ZD??ZD??ZD?ZD ?ZD??ZD ??ZD ?Z7 ?Z8??ZD?[D??[DO??[CH?À[C>?À[Cx?À[B ?À[B ?À[B?[Bǀ[B?À[B?[B?[B [A<|?[A80??[A8 ??[A 8 ??[A? 8 >[A  8 ?[@ 8??[@ ??[@ 8 ??[@  ??[@p ??[@  ??[?
 <??[?
 <<??[?
 x <??[?
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  x?ZB x?<? YBx?<? ?YC
|< YC
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  ?XC
  XC
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?ÀXC
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SB?SB?SB?SB?SB? S B? ?RB? RB? RB?!RB?!ÀRB?!RB?!?QB?!QB?!QB?!QB?!QB?"QB"?PB#PB#?PBs?PBÀgǀPBÀ$ÀP BÀ$ǀPB$OB$?OA$O/$O/$OA%OA%ÀO A%OA%?NA%?NB%?N B%?NA%?NA%NB%NB%NBÀ&NBÀ&NBÀ&N BÀ&ÀN B&NBÀ&NB&NA&N A&ÀN A&ÀNA&ÀNA&NA&NA&NA%NA%NB%NB%N B$NB?$NB?$NB$?NB?$OB?$OB?$OB$ÀOB$?NB$N B$NB$NB$N C#NC?#NC#NC$NC$NC$JD$ND$MD$?MD$MD?#MD?#MD?#?MD##MD$CME$ME$M E?"ME#ME"M E?"MD #MD#MD#MD#M D?#MD$MD$MC$MC$MC$MC$?MC$?MC$NC?$NC?$NCÀ%NC$N@ $N@ $N@  $N@ #t?N?# N?#O?#O??% O> ?% ?O> %P= &P= &P= &P='P< (?P<(Q<(Q<À)Q ;)?L;?)L;)L; *L:*L:* L:*?K:*K:*K9+K9+K9?+K9?+K9,K8,K8,ÀK8-K8ǀ-?J8À-J8À-J8À-J8À-?H8-H7-H7-H7?-H7?- ?H7?-
? ?H7?-
? H7-	I71I7À.	I6.	I6. I6?. I6?.?I6.J6/?J6/E6/ ǀE5/? E5/ E5?/?=5?/   =5/   55/  	? ׀15À/    ?05/     05/ <     04/#      04/#  < ??     04.$        04?.        04?.?     2d??  >   2d   0     2d"      2d$?     0d      0d ??      0d ?       0d   ?     0d  
>0d  
0d   0d  0c?  ? x0c    04À. 	 >?  04. 
  03.?  03.  03. ?73. ?HcHdHdHdDd?Hd?HdKdKdK30?A30A20??A20A20A20A21
A2?1 
A2À2
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A04  
A04  
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< <.:  <.:   <.?:  ??<.:
  =.; =.;=-;=-; =-;?=-< ? >-?< >-<  ?>-=   >-=>,=??>,= ?,> ?,>
  ?,>
 ? ?,?>
? ??,>@+???@+? @+@ @+@? ?* @a ?* A?~  ?* ?A> @?* A>?*B?* B ?)C  ?)C??)C??)D
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 l5 l5m 4n 4	n4n4n4?o 4p3p3p3p3p3p 3q 2q 2q2q2r2 21?'G1'G1' G 0'  D 0&
   70&
     70'   
  3 ?/?'    
  ! /(       /(?  p   	?π /(      /(  ?      /(   ? ?        ?.(          .(            .(    ?   ?     .(        ??   .(    p    ?    .(    p    ?? -(   
 ? ;    -(   
 ?      -(   
?    x   -(        x  -(    p   x  x    -( ?  p   8 x    ,(      0  ,)?p       ,)        p,,
         x ,,
 p       |  ,,
      x  p   ,,
   ? x  p   +1 ??x      +3?x    ?   +;x    !+;x  ! ?*G	߇x @" *H"*K"*K"*{*}?)|)|)?|)})~?( ~( ~(~(~(
 ~(
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S,?'
'
'
'	w'?'''&&&&&&&?&&?%%%% %% %
%
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Q4$
$
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$	$	$	?#	#	#	# 
###	?#	?#	# 	# 	#	#	## #?b'?""" """ " """"""" " " "!! !!!!! !!! !? ?                                 ? 

 ?   9߀`                 ?     !{!{!{!{?!{!{ 1߀k  ?&߀w   ?           ov   4      &l9         	 IG=l: fl    I% % K K  ;V;W 0߀b 0b0Àb0a0a0 `0  `  ?_?  _? ÀO?	
 ÀO
?ÀF 	8? ÀO   ?	<?O  ?	<??O ? 	<??O
   	<???N
  ? 	<??=
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= ?À?
= ?= 	 = À	 <  	
 
<  	 À ;
À ;
À ;%?  :%?À ?:%À??:%À??:%À??:%?'??9&???
?8&???
8& 
8& 
8& ?
8& ?8& ?À8&?À8&?8&
G2Z2Z2À?J2ÀJ3J.?
J.?
7.???5.??5 .?4 .?4 -??3 -?3  ?-?3 -??3 -??2 -?2'?2'?0 ?'??0 '0'?0' ?0'?? 0'?? ?/ '? . &	 ??.&	 ?.&	??(&	π &, @  ?&  ?
, &??   
,?		 ??  
,		  ? 
, ??  g  ,       	+    ?  	  ?*    ?	 s)    ? 	 )   	  ) ?  ) ? ?  (  ??  ( 
  ' 
 ?&  
  %   
 % 
 $  ?$  ? $ $ ?$ ?À? n
 ?# À	  ?	 #  	#? 	# 	 #    	 "      	 " ?  ??	"   	"	 "
 ! (

 (
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  )
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    ?)  ?
  ?)  @  
 !+?
   
!*
 ?   
!*  w 
* 
!*?	"*?	"+	"+ 
 ",
 ",
 "B
  ?"B
  #C #C	 ?  #C	   #C $C  $C
 $C
 <$&
 $C
$CC$C $C#C#C$ D#D#D#D#D#D #D#D#D#D?#D"D"D"D?"D "D  "\ "E "E "E "/?"/ "E "E "E"E !E! E!E!E!E?!E!E!E!E!E!EEEEEEE E  E E E? E F F  F  F   F F F  F  F  F  F F F F  F? F F F F߀ F F Fπ  F  F  F  F ? F ? F ? F? ? F  F ? F ? F  F  F? F? F F F F߀ F F F F F F FO F F F F
ÀF?
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  G
  R  ?S ?S!K!K!K(?K(K(L( ?Hǀ( ?H!?Hπ!H!H
" H?
"H
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 L
?$L
$L%L%L %M %M%?M %M ?%N%N?%N%O% O%O%O&?Oǀ4O O *߀$ `O ? ?O ?  ??O??  ?  ?O?? ? ? O? ?? O? ?O?|?O ~?O? O<? 
?	Ox?  
 ?	Ox?? À
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? 	88?? ??>
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  `?H?
    L   ? L  ?L? 	 L?? ?	L?
 L? ?L? LKKK
z?K
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"   ? 
 
 "   

 # p  	 #   	 ?
#   	  ?# 
  #  
  # 
 
 $ 
 
$ @ 

  ? $       
%  ?  	    
 %          ~ %              %         
&      x  Є &     ~  &   ' "?(	 " )	  !)	   !)	     !)    x  ! )    p    ?)    0 1   &   p ?     &  x /      &    ?   &     x   &    px  &    px   & 	 px   & 	 p
x   &	  0
~     ?&	   p     "	    p>   & 	     p    O' ? 
 x     p  ~  '  
? ?  x  p  '  
    p  '  	    p  >'  ?  p    '  ?       	 '#        (%      ?(&ǀ p 	 ?( 
@ 	 ( π   
  (    
 ?(     (    p   (  ?      ߀(       (    
  )   ? 
  )      
  )     
  ?߀?)       
    	)      
?   	)    
   	 *    ?
  ߀*p   
 
*  ? 
*   	π
*   ?
 	*>  
	+  
	 
+>     pp >		 
+
   _  p p  		 +
   p p  		   +
   p p  		  ?+
  p p   	 +    p p    
    @+     p p  O 

 `  ? x ,     p  pp   	   ,  p  pp?   ?,   p    	  ,  > p     ?,     p x   
 ,p  x 0 x 
  ,     | 
  -   0  ~ ?
  x  -z p     -  p  |    ?-  
x  0   ?Ȁ -    }.  σ  . 	 p ? ?.  x   /  
/
    
/
      p@ /
       /
  ?  ?/
 ? /
   0
  
 ߀0
      /3   
 4( y  6(  
   6(  
 8)  ?߀ 9)ǀ    :F  
 :G 	  ;G  ?π =H   =H =I >J ?J AM AM
B ?  chapter    #  ] 	[ 
    P fQ   
P# 
    
  t                g H    #  H 	`>	    xi fQ  ԩX# Marine and Coastal Image Data Module 5:t  k              x  } S    `(#X #  H 	`>	    xi fQ  ԩX# Practical Lessons: 8k #  ] 	[ 
    P fQ   
P#    
  W   
  3'                                          3'Standard                                  6&                                          6& Standard zar estilo t)cnico            ܰ                                          


   !  Practical Lessons using Marine and Coastal Image Data
 ; a 
 ; a 
 ; a 
 ; a 
   ^     K #  qs 	[ 
    P fQ  P# 8: STUDY OF THE DISTRIBUTION OF SUSPENDED SOLIDS IN THE
 "  WESTERN COAST OF MARACAIBO LAKE (VENEZUELA), USING
 5  LANDSAT DATA
 ; a # ] 	[ 
    P fQ   
P# 
 ; a 
 ; a 
 ; a 
  ~ R   5 = Aim of Lesson
 ) `      
To experiment with the use of contrast enhancement by separation into ranges of the image gray level
values over a body of water.



  ~ S ^ a6 Objectivesă

Upon completion of this lesson you should be able to:

1) use the BILKO program for the location and identification of suspended solids

2) process images to enhance the characteristics which show the distribution of solids in the waters
of a lake

3) work with the characteristics of an image to enhance the features being studied.




  ~ S  a0 Background Informationă

  ~ R ` The BILKO image processing program

Familiarity is assumed with the use of BILKO to display satellite images. At any moment it is possible
  } S ! to access the help option by typing <h>, which explains the operation of the command being used.
  } S " Press <esc> to return to the Main Menu.


  ~ R % Other Equipment

To work on this lesson, you will find it useful to have graph paper and coloured pencils to represent
some of the observed characteristics.


   )         o.?+?+HH  Ԍ  ~ R    ԙThe Study Zone

In the geographic context, Maracaibo lake is located in the western region of Venezuela, between
9$00' - 1030' North and 71$00' - 72$20' West (see Figure 1).

Maracaibo lake is oval in shape, is about 150 km long in the North-South direction, and 110km at
its widest part, in West-East direction. The average depth is 25m, with a maximum of a little more
than 32m in the southwestern part of the lake. Maracaibo lake may be treated as a system in which
the dynamics of its waters is the result of the combined effect of several natural factors: salinity
changes, changes in Trade wind direction and magnitude, Coriolis force and discharges of its two
principal tributaries (Escalante and Catatumbo). The currents in the lake vary both spatially and
temporally, exhibiting diurnal changes in direction and speed. Nevertheless, the predominant
movement in most of the water of the lake is in a clockwise direction.

The discharge of the Escalante and Catatumbo rivers, located in the western margin, generates an
important current which deviates northwards along the coast until it reaches Cabimas. Here part of
the water leaves by the strait and part remains in the lake, deviating to the west under tidal influence.
In terms of discharge, the main tributary is the Catatumbo River, which supplies about 70% of the
fresh water in the lake. This river brings the main natural contributions of sediment. The
northwestern sector of the lake presents a particular pattern: it behaves like a low energy zone in
terms of horizontal water movement, so floating material tends to accumulate.

The body of water behaves like a partially mixed system. It is possible to differentiate four zones with
different characteristics. In the Northeast and at the lake outlet is located the Gulf of Venezuela, with
waters classified as eurihaline (30 % - 40 %); in Tablazo Bay and the Maracaibo strait the waters are
classified as mesohaline (5%  10%); the waters of the lake are oligohalines (0.5 % - 5 %) (see
Figure 2).

The water temperature exhibits small horizontal fluctuations, due mainly to seasonal changes. The
vertical fluctuations in the water column are not pronounced, with a surface to depth difference of
0.1 $C to 0.5$C.

The system shows a bimodal annual rainfall regime, with an average value of 1,200 mm. The main
peak occurs in October and the secondary one in May; the minima occur during February-March and
July-August. The mean annual air temperature in the region tends to be constantly high, with
fluctuations between 26 $C and 29$C, with small interannual variations. The climatic fluctuations
generate a seasonal thermal pattern, with the highest temperatures in June and September, and the
minima between January and February. In general, the variations do not exceed 4$C, with the
maximum values around 33 $C, and the minimum close to 27$C.

The study site was selected because of the results of earlier work on the whole water body of
Maracaibo lake. The focus of the present lesson is on the northwestern sector of the lake since it has
become evident that this has the greatest productivity and highest values of suspended solids content.
   "         o.?+?+HH    ! tt'
H                  #  d d     LAGO.PCX                                             tt)   Z 
  ~ R        Figure 1: Schematic diagram of Maracaibo Lake  $  ""  _	_	  ! _	b$ 
 ! _	b 
 ! _	b 
 ! _	b   A 
tt'
J                 ov  d d     LAGO2.PCX                                            tt)  wCT 
  ~ R      	  Figure 2:  Bathymetry of Maracaibo Lake   ! _	b 
 ! _	b   
 ! _	b 
 ! _	b 
 ! _	b  @           o.?+?+HH!  _	HbL  !   _	b1A  @    _	_	  ""   
  ~ R   Image Data

This lesson uses a Landsat-TM image of the western coast of Maracaibo Lake, near the city of
Cabimas, State of Zulia (Venezuela). It uses two image files on which the land elements have been
subjected to a previous masking treatment.



c  
    d d x                             !         P   X              @@@@@@  c   	 		 	 	 	 	 	P              
Image Name   	      &  
 #  Sensor   	      6  
 4  Date   	      E  
 C  Size   	      T ? 
 Q  Channel   	      c 2  
 ]  Image Quarter  	 		 	 	 	 	 	P              
  ~ R 	 DP753HB2  
      &  
 %  TM  
      6  
 2 Q 19/04/89  
      E  
 A ; 512 * 256  
      T ? 
 T  2  
      c 2  
 b  Q2  	 								 	              
  ~ R  DP753HP3   p      &  
 %  TM  p      6  
 2 Q 19/04/89  p      E  
 A ; 512 * 256  p      T ? 
 T  3  p      c 2  
 b  Q2 			 
     

  ~ S  a4 Lesson Outlineă

Part 1:

  ~ S Q 1.1. Load and display image DP753HB2 using the functions Load Image and Display Image.

  ~ S  1.2. Load the VGA.PAL palette. What do you see on the screen? Why is not possible to see the
displayed image?

  ~ S c 1.3. Use the Linear Stretch function in the Modify LUT Menu to adjust the minimum and maximum
gray levels to values close to the mean. Why is the contrast improved?

  ~ S  1.4. Select the Histogram Equalization function from the Modify LUT Menu. The program produces
an image with contrast in which the pixel values are redistributed to give a display in which the
  ~ S u contrast is increased. Compare the Histogram Equalization function with Linear Stretch. Do you
observed any difference between the control of limits in the histogram and the direct product of the
image?

  ~ S  1.5. To obtain a better colour display, load the EGA.PAL colour palette. Use the Manual Stretch
  ~ S  function of Modify LUT. In the image it is possible to distinguish several solid distribution patterns
associated with the lake coast. Nevertheless, to improve the assignment of colour and the contrast,
you are recommended to create a new palette. When you have done this, compare your palette with
  ~ S  palette DP753C2.PAL, which is included in the lesson.


Part 2 :

  ~ S 	$ 2.1. Repeat steps one to three of Part 1 with the same image (DP753HB2).

  ~ S % 2.2. Use the Cursor function, to pick out the largest and smallest values among the gray tones. From
them, establish ranges for the remaining values in a total of six intervals. The different gray level
intervals correspond to different relative concentrations of suspended solids. Differentiate them as
a function of the recommended ranges for band 2.

   ; a    )        o.?+?+HH  Ԍ 2 . RADIOMETRIC RANGES
 0  (GRAY LEVEL INTERVALS)
 9   030
 9  3140
 9  4149
 9  5058
 9  5967
 9  6878
 * a      

  ~ S   2.3. Create a colour palette based on differentiation of the previous values using the Manual Stretch
function. For the purposes of this lesson, it is possible to compare the palette made with that given
  ~ S 	 (DP753C2) as a function of the gray values of the table. What do you observe?

  ~ S b 2.4. Load the colour palette created using Load Palette.

  ~ S 
 2.5. Use the Toggle function to compare the results obtained in Part 1 and Part 2. Are the two images
the same? If not, why not?

2.6. Repeat steps 1-5 of Parts 1 and 2 with the image of band 3 from the Landsat-TM. It is only
necessary to select ranges from the new graylevel values corresponding to band 3. Examine the
images to see if there are any differences: do you see any differences?


  ~ R     , c Suggested supplementary reading
 * a      

There are numerous works about quantitative sampling in studies of water quality, but few are related
to the application of satellite images in Venezuela.

 X  Ravelo, P., 1991. Aplicaci;n de Imgenes de sat)lite LandsatTM a estudios de calidad de agua en
el Lago de Maracaibo."

      y    b !                    d       d d                                                                         y 

This lesson was prepared by Daniela V. Pal Pernia and Mar1a D. G;mez Toscano.




   Q  Suggestions and comments regarding this lesson should be sent to:

Daniela V. Pal Pernia
Instituto de Ingenier1a  CPDI
Apdo Postal; 40.200
Caracas 1040A
VENEZUELA

   Q D& Fax: (582)  962 10 25   D&         o.?+?+HH    ~ S    La2 Answers to Lesson 8ă


Part 1:

1.2. No image appears. The pixel values connecting to the lake surface are very low. This requires
an adjustment in the distribution of pixel values in the histogram. Furthermore, the image used is a
masked image over land, which contains a high number of pixels with the value zero. This produces
a deviation from the real value of the mean in the normal distribution of the histogram, since not all
values come from water.

  ~ S  1.3. The adjustment of the histogram with the Linear Stretch function controls the minimum and
maximum values in the radiometric response. This allows an improvement in the contrast of the
image by redistributing the pixel values in the adjusted histogram. In the image it is possible to
distinguish the behaviour and distribution of solids along the coast of the lake.

1.4. The two functions give the same result. The operator can thus be sure that the selected limits
are similar to the limits chosen by the program.

  ~ S r 1.5. The results obtained from the two palettes are visibly different. The EGA.PAL palette uses a
greater number of colour combinations: the new palette adjusts to the range of pixel values assigned
by the operator.


Part 2:

2.3. There is a loss of detail.

2.5. When comparing the images, the colours appear with different tones. The reason is the number
of pixels assigned to the ranges created by the operator. If more than six ranges were created, it
would be possible to observe in the coloured image finer differences in the solid content indicated
by the image.

2.6. Yes: but the differences in the results are very subtle. The distribution of suspended solids
appears similar with only minor differences.