combine

Name

combine - combine two bands

Syntax

 #include <xite/combine.h>

 int combine( IBAND b1, IBAND b2, IBAND b3,
    int expr1, int expr2, int expr3, int expr4,
    char* relop );

Description

Combines two bands into a third as follows:

 FOR (every pixel) DO
   IF (expr1 relop expr2)
   THEN b3 = expr3
   ELSE b3 = expr4;

-where:

 b1 - first band to combine
 b2 - second band to combine
 b3 - output band
 expr1, expr2, expr3, expr4 can have values:
      -1 for b1[y][x]
      -2 for b2[y][x]
      0..255 for 0..255
 relop - one of ("EQ", "NE", "LT", "LE", "GT", "GE")

Return value

 0 => ok
 1 => bad pixel types
 2 => bad sizes
 3 => unknown relop

Author

Tor L|nnestad, BLAB, ifi, UiO.

Id

$Id: combine.c,v 1.24 1997/01/08 10:11:55 svein Exp $