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c# - Usage of Server Side Controls in MVC Frame work -

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i using asp.net 4.0 , mvc 2.0 web application. project requiremrnt have use server side control in application not possibl in noraml case. ideally want use adrotator control , datalist control. i saw few samples , references in codepleax mvc controllib howwver found less useful. can tell how utilize theese controls in asp.net application along mvc. note: please provide functionalities related adrotator , datalist controls not equivalent functionalities thanks in advace. mvc pages not use normal .net solution makes use of normal .net components impossible. a normal .net page use event driven solution call different methods service side mvc use actions , view completly different way handle things. also, mvc not use viewstate normal .net controlls require. found article discussing mixing of normal .net , mvc.
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optimization - Retrieving the most significant features gained from SIFT / SURF -

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i'm using surf extract features images , match them others. problem images have in excess of 20000 features slows down matching crawl.

is there way can extract n significant features set?

i tried computing mser image , use features within regions. gives me reduction anywhere 5% 40% without affecting matching quality negatively, that's unreliable , still not enough.
additionally size image down, seems affect quality of features severely in cases.
surf offers few parameters (hessian threshold, octaves , layers per octave) couldn't find on how changing these affect feature significance.

after researching , testing have found hessian value each feature rough estimate of it's strength, using top n features sorted hessian not optimal.
achieved better results when doing following until number of features below target of n:

  • size image down, if overly large
  • only features lie in mser regions considered
  • for features lie close each other, feature higher hessian considered
  • of n features per image want save, 75% features highest hessian values
  • the remaining features taken randomly remainder, weighted distribution of hessian values computed through histogram

now need find suitable n, around 1500 seems enough currently.


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