Preserved Topic: Help with edge delineation (Page 1 of 1)

I'm trying to extract single lines from an image which is a bluescale rendering of a building. The problem I am having is that some lines are not at the extreme of my blue range. I need to find a way of darkening the lines around doors, windows, etc. without darkening the same color within the bluerange. Then I should be able to reduce my image to a few colors via levels. I've tried all the stock PS6 filters, no help. Any help in here???

An image of the image you are working on would be nice...

What you could do is go to the channels palette (It's another tab next to the 'layers' tab, and look at which channel has the most definition. Most likely that's either the red or the green one (I'm assuming you have white lines on a blue background) Duplicate the channel with the most detail, and fiddle with the 'levels' or 'curves' commands if nessecary. If you now control-click on the channel, all the white parts will be 100% selected, and the black parts will be 0%. Gray parts will be more selected the brighter they are. Select the RGB channel to go back to normal mode again, and click on the 'layers' tab. you can now fill your selection. Map completed.

Thanks for the help, either that doesn't fix my problem or I did it wrong. My problem is that everything in the image is blue. ranging from light (almost white) to dark blue. Since it is a perspective drawing, some lines are darker blue than others. OBTW, how would I attach a file in here? Or could I just mail you a sample??

Just mail it to me and I'll put it up this time... it's the icon.

For hosting for your images, you can look here.

Depending on the specifics of the original image, and exactly how perfect you're looking to get, it's quite possible you won't really be able to get what you're after.

It would definately help if you gave a few more specifics about what you want the result to be, and get the image online one way or another...




[This message has been edited by DL-44 (edited 01-06-2003).]

Method: first [image>adjust>desaturate]

Then auto levels (ctrl-shift-L)

Then the levels setting you see on the picture.




Edit: I know it's not really a high-tech solution, but it's all I can think of. Unless you'd want to trace it over, or erasing all the wrong stuff by hand.

[This message has been edited by mahjqa (edited 01-06-2003).]

also try IMAGE--ADJUST--THRESHOLD

gets a similar result to above...

I'm not sure I understand what you're looking for.

Do you want lines of differening thickness? Or are you looking to sharpen the lines while keeping the overall shading the same?

Thanks to all who replied, what I was looking to do was isolate the lines themselves. This would produce a simple blueline drawing suitable for blueprint package cover sheets. I used the levels method to isolate the lines as best as I could. Couldn't get the lines tightened up enough to pass as a complete line drawing so I took at bitmap image into AutoCAD and traced it. Thanks again for all the kind help.