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llmap

$ \bigcirc$Name


llmap Map the level lines of an image




$ \bigcirc$Command Synopsis


llmap [-s level_step] [-t] image level_lines



-s level_step : gray level step (default:20)

-t : code the type of border

image : image input

level_lines : level lines of input




$ \bigcirc$Function Summary


Cimage llmap (ls , tmap , input , output )

short *ls ;

char *tmap ;

Cimage input ;

Cimage output ;




$ \bigcirc$Description


This module produces a basic representation of the level lines borders of an image. To get a more sophisticated representation, see the modules ml_decompose and ml_draw. Because this is a bitmap representation, borders at the same location are represented only once : the borders are also borders of the iso lines.

The parameter level_set is a step on the gray level. If set to 1, all the level lines are caught. If set to a larger value then only the level lines coresponding to a gray level value which is a multiple of level_set are catched.

For a better representation of the level lines, we invit the user to do a zoom of factor 2 on the input image, before calling this module.

The option -t allows to code the type of border : not a border corresponds to value 255, left border to 200, upper border to 100 and corner (up and left border) to 0. Without this option, only the values 255 (not a border) and 0 (any type of border) are used. The map obtained with the option -t allows, together with the gray levels sequence of the image (one pixel for each connex component, see module encodelevels), to reconstruct the original image (see module glmaprecons).




$ \bigcirc$Version 1.6


Last Modification date : Thu Nov 29 20:23:56 2001


$ \bigcirc$Author


Jacques Froment, Frederic Guichard






next up previous contents index
Next: ll_remove Up: Reference Previous: ll_extract   Contents   Index
mw 2004-05-05