Table 2. Univariate analysis of the main features relevant to the prediction of TB positive objects.

Morphological Features	Features (unit)	Mean	Standard Deviation	Minimum value	Maximum value
Width of object	rel_width (pix.)	11.85	3.48	3.10	39.61
	SD_width (pix.)	4.16	1.70	1.33	26.79
Ilumination of object	Mean-Nrefr15 (prop.)	74.67	3.77	59.27	84.51
	bimedia (brightness units)	51.64	2.61	43.94	62.67
Form and length of object	Num-tips (non-dimensional)	8.52	4.31	3	28
	perimeter/length(prop.)	2.23	0.15	1.97	3.84
	max-width (pix.)	23.56	6.28	11.70	79.19
	SD-for (pix.)	8.54	4.36	0.99	35.85

(pix.): pixels; (prop.): proportion. The statistics shown were estimated from 1223 positive cords.