Featured post

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

-
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.
3 comments

Computer Vision: Detecting Parabolas using the Hough Transform -

-

papers have been written describing how hough transform can generalised detect shapes circles , parabolas. i'm new computer vision though , find these papers pretty tough going. there code out there detection more want. wondering if briefly describe in bullet points or pseudo-code how hough transforms used detect parabolas in images. amazing. or if knows basic explanations online haven't come across enough :).

thanks :).

interesting question. looks great resource. included summary (loosely quoted). see source mathworks @ bottom of answer - matlab has houghlines , houghpeaks functions useful you. hope helps.

  • run edge detection algorithm, such canny edge detector, on subject image
  • input edge/boundary points hough transform (line detecting)
    • generate curve in polar space (radius, angle) each point in cartesian space (also called accumulator array)
    • extract local maxima accumulator array, example using relative threshold
    • in other words, take local maxima in accumulator array values equal or greater fixed percentage of global maximum value.
  • de-houghing cartesian space yields set of line descriptions of image subject

cs.jhu.edu: http://www.cs.jhu.edu/~misha/fall04/ght1.pdf

code mathworks: http://www.mathworks.com/help/toolbox/images/ref/hough.html


Comments

Post a Comment

Popular posts from this blog

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

-
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.
Read more

ios - Very simple iPhone App crashes on UILabel settext -

-
i have simple application. have button , label in ib. have ibaction onclick calls settext on label. there's outlet label. connected in ib. crashes app first time in simulator. when launch again, sets text. crashes again next time. crashes on actual device. should simple, i'm not sure i'm doing wrong. thanks. in .h file : #import <uikit/uikit.h> @interface untitledviewcontroller : uiviewcontroller { iboutlet uilabel *label; iboutlet uibutton *button; } @property (nonatomic, retain) uilabel *label; -(ibaction) onclick1: (id) sender; @end and in .m: - (ibaction) onclick1: (id) sender { //[label settext:@"hello world!"]; label.text = @"hello world!"; //[button settitle:@"clicked" forstate:uicontrolstatenormal]; } sorry, i'm new site. how crash log , stack? thanks. edit : while answer technically correct, doesn't answer question @ :( sorry < warning - guess > if you're...
Read more

mysql - Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause? -

-
why there can 1 timestamp column current_timestamp in default or on update clause? create table `foo` ( `productid` int(10) unsigned not null, `addeddate` timestamp not null default current_timestamp, `updateddate` timestamp not null default current_timestamp on update current_timestamp ) engine=innodb; the error results: error code : 1293 incorrect table definition; there can 1 timestamp column current_timestamp in default or on update clause this limitation, due historical, code legacy reasons, has been lifted in recent versions of mysql: changes in mysql 5.6.5 (2012-04-10, milestone 8) previously, @ 1 timestamp column per table automatically initialized or updated current date , time. restriction has been lifted. timestamp column definition can have combination of default current_timestamp , on update current_timestamp clauses. in addition, these clauses can used datetime column definitions. more information, see automati...
Read more