http://imagej.273.s1.nabble.com/Ideas-for-Algorithm-tp3683675p3683676.html
Process/Binary/Make Binary and Process/Binary/Fill Holes. This converts the
Then, do Analyze/Set Measurements and select Area, Bounding Box. and I think
Now run Analyze/Analyze Particles. You will get the selected properties
including the Bounding Box spec in a Results Table. You may want to write
(aspect ratio). This can be done using built in macro functions to get
> Hi .... I am writing (or rather have substantially written) a program in
> Java to take a scanned page of stamps and attempt to create subimages of
> the
> stamps (and allow me to quickly save them in certain directories with
> particular names).
>
> I am struggling a little bit to come up with the right algorithm to "box
> off" the stamp images that I need to crop. I just need the rectangular
> bounding boxes so I can present these in my interface, make any changes and
> proceed in the application to burst them into subimages.
>
> An example image is here (warning it is a 50Mb image):
>
http://stamps.drakeserver.com/scan005.jpg>
> Though investigation I found ImageJ. One thing I have managed to use
> ImageJ
> for is to convert the image to binary format (and filter with a threshold).
> This gives me a working image (obviously my cropping will occur from the
> original) that is easier to deal with. I may also use their image object
> instead of BufferedImages as these are memory hogs:
>
> Here is the filtered image:
http://stamps.drakeserver.com/scan005-5.jpg>
> My current algorthim is quite dum.... I start in the top left and proceed
> on
> a forty-five degree angle toward the bottom right. As soon as a catch a
> color change I mark it and attempt to achieve a 10 pixel threshold. At
> this
> occurance, I will try and find the top left corner of a stamp, and
> conversely attempt to find the lower right corner. Since they are in rows,
> I
> will move to the right and attempt the same thing for stamps to the right
> (if I hit the edge I go to next row). I keep track of the lowest "y" value
> and use that for my next row. The perforations make this tricky. The
> algorithm is only ~ 80% efficient and struggles when I come into gaps (ie.
> stamps I have removed) I also can skip rows if there are not stamps in the
> first couple slots on the left.....
>
> Another thought I had was to start top right and simply scan to the right.
> As soon as I hit multiple "white" pixels (say 10) I start to determine if
> there is an area under them (ie. it isn't simply a reflection line but
> represents a stamp shape). I proceed down the rows until I hit matches.
>
> My background is engineering and computer science (but not graphics
> focussed) so I am not particularly up-to-speed with algorithms for this
> type
> of thing. I would welcome any input on how to computationally solve this.
> It will drastically save me time in scannign and cataloguing my collection
> (although I have to admit the time I have put into my program could've
> better been used on my hobby and just use Gimp, but well..... the computer
> scientist in me loves to tinker.
>
> -Jason
>