[Insight-users] Canny Edge Detection Filter Qns., etc.

[Kalpathi Subramanian]

1. I am wondering about the two hysteresis thresholds (lower and
upper thresholds) in this filter.
If I remember this (I implemented all of this in my post-doc BSP tree
project many, many years back), the thresholds were on the 
CDF(cumulative distr. fn) of the gradient magnitudes. Is this the case 
here? Or are the thresholds on
just the gradient magnitude (maybe my implementation was based on
another related implementation, I dont quite remember). Anyhow, this
had the advantage that I could give these thresholds as percentages
on the CDF..

2.   - on reading raw data. There is a .mhd file needed
to read raw data. Can someone point me to its format?

3. Has anyone read the Colon datasets available from NLM 
(nova.nlm.nih.gov) - I have tried it with the itkDicomSeriesReader
but have had problems.. will try again but the images didnt
seem like the original CT data; instead looked like binary images..


Thanks.

	-- krs


-- 
K.R.Subramanian                        Phone: (704) 687-8579
Department of Computer Science         FAX:   (704) 687-3516
UNC Charlotte, STech 435E              Email: krs at uncc.edu
Charlotte, NC 28223-0001               Web: http://www.cs.uncc.edu/~krs