A couple of ideas: Find a threshhold of the image so that it makes good picture of the feature (the dot).
(<./ , >./),16bff bAND readimg 'testdcm.bmp' 120 129 viewmat 125<16bff bAND readimg 'testdcm.bmp' Then apply convolution with a kernel that is a copy of the feature with neighborhood of the size of the feature in all directions, e.g. if dot is 8x8, use 24x24 kernel; and a matching function, e.g. dyadic +/@,@:= then the max of the convolution will be the sought point. And the FVJ book is an excelent resource. --- Björn Helgason <[EMAIL PROTECTED]> wrote: > I downloaded this just now and paged through the labs. > > It looks very nice and very impressive. > > I do not much about working with images. > > I do have an assignment to work with .bmp images and locate an instrument in > a phantom. > That is a a transparent phantom with four holes around the edges and one in > the center. > It is round like a clock. > On the .bmp image I can clearly see the black spot where the instrument is > with the phantom white or rather gray around it. > Around the phantom there is black also. > > I have opened it with transform image and viewimage as well as with viewbmp > and it looks ok visually but how to operate on it with programs to find the > spots I do not know how to do. > > I need to find with J where the phantom is located in the image and then > find the black spot inside the phantom. > getting the x,y coordinates of the leftmost, right, top and bottom of the > phantom would be ideal and similarly getting the x,y coordinate of the black > spot inside the phantom circle. > > Can someone point me in a direction how to perform reading like that from a > .bmp image - preferably with with J tools? > > This may be dead easy but for me at the moment it is not. > > I am told people do this with Matlab all the time but I rather try out with > J if at all possible. > > 2007/1/17, Cliff Reiter <[EMAIL PROTECTED]>: > > > > Just a note that the image3 addon has been updated for J6.01 and > > is available from the wiki jsoftware pages. Directory changed to > > ~addons/media/image3 > > Help files for the addon are at > > http://ww2.lafayette.edu/~reiterc/j/image3help/index.html > > if you want to know what the addon does. > > > > Also, a new addon has been added that depends upon the image3; > > The fvj3 addon > > ~addons/graphics/fvj3 > > It is primarily meant to provide scripts and materials for the 3rd > > edition of Fractals visualization and J (coming soon), > > but the addon may be of use in its own right, and there are > > several labs, designed to explore the scripts (not book teasers). > > But I have to add a tease since I added a script to the fvj3 addon > > that can be used to replace missing image data (bafrmid.ijs) and > > running the corresponding lab is kind of amusing. > > An illustration of what "replacing missing image data" means can > > be seen at > > http://ww2.lafayette.edu/~reiterc/mvq/bafrmid/index.html > > J is cool. > > Best, > > Cliff ____________________________________________________________________________________ Don't pick lemons. See all the new 2007 cars at Yahoo! Autos. http://autos.yahoo.com/new_cars.html ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
