SUN_source_code_v2/code/sift_vgg/README.txt

This package contains statically linked Linux binary and Windows executable of 
Maximum Stable Extremal Regions detector.

Usage: extrema [options]

    -i (null)    [null] input image (png, tiff, jpg, ppm, pgm)
    -o (null)    [null] output file
    -per (0.010) [0.010] maximum relative area
    -es (1.000)  [1.000] ellipse scale, (output types 2 and 4)
    -ms (30)     [30] minimum size of output region
    -mm (10)     [10] minimum margin
    -rel (0)     [0] use relative margins
    -t (0)       [0] output file type 
                      0 - RLE
                      1 - Extended boundary
                      2 - Ellipse
Dependencies:

    Option -i is compulsory

Detected MSER+ and MSER- regions are stored in output file as follows:


Extrema file format RLE:

NUM_MSER_PLUS
NUM_RLE LINE COL1 COL2 LINE COL1 COL2 ... LINE COL1 COL2
...
NUM_RLE LINE COL1 COL2 LINE COL1 COL2 ... LINE COL1 COL2
NUM_MSER_MINUS
NUM_RLE LINE COL1 COL2 LINE COL1 COL2 ... LINE COL1 COL2
...
NUM_RLE LINE COL1 COL2 LINE COL1 COL2 ... LINE COL1 COL2

where NUM_MSER_PLUS and NUM_MSER_MINUS are number of MSER+ and MSER- regions 
respectively. Each region is described as one line in output file. 
NUM_RLE specifies number of RLE triples LINE COL1 COL2.


Extrema file format Extended boundary:

NUM_MSER_PLUS
NUM_PTS X Y X Y ... X Y
...
NUM_PTS X Y X Y ... X Y
NUM_MSER_MINUS
NUM_PTS X Y X Y ... X Y
...
NUM_PTS X Y X Y ... X Y

where NUM_MSER_PLUS and NUM_MSER_MINUS are number of MSER+ and MSER- regions 
respectively. Each region is described as one line in output file. NUM_PTS 
specifies number of points in extended boundary.


Extrema file format Ellipse:

1.0
NUM_TOTAL_MSER
U V A B C 
...
U V A B C

where NUM_TOTAL_MSER is number of MSER+ and MSER- regions. Each region is 
described as one line in output file. Each affine region is described as an 
ellipse with parameters U,V,A,B,C in:
 
a(x-u)(x-u)+2b(x-u)(y-v)+c(y-v)(y-v)=1

with (0,0) at image top left corner.