Topic: Raster Design - Despeckling

[M-dub]

Hey All

We've used CAD Overlay in the past and we're now at Raster Design 2004.

I'm wondering if anyone out there shares the same problem as we have here with some of our 'poorer' quality scans.  In almost all cases, the originals look just as bad, but I'm sure everyone's seen old blueprints, sepias, mylars, etc. that have real blotchy, dark areas where you can barely read the drawing and other areas of the same drawing where it's almost too faint to make out.

I guess I'm asking if anyone has mastered the despeckling of raster files.  I can do it, but to get the desired result, it takes about 3 -5 passes.  Does anyone use progrmas other than Raster Design or other Autodesk apps?

Here's an example of what I'm dealing with...

Thanks, Folks!

[PDJ]

It looks like they drew that right over a black and white aerial of a forest somewhere..

[hendie]

I'm not sure what you'd like as the finished result but I just dropped it into Paint Shop Pro, adjusted the brightness & contrast (brightness 0, contrast 50%) and the image was a lot more readable

[Bob]

We use GTX RasterCAD which bolts onto AutoCAD.

If a scan is unreadable we try to get hold of the original and rescan. Usually, we send out to contract the rescans. With various passes at different contrasts we get an image that can be stitched together.

Quite often when we try to despeckle, the natural antialiasing is lost.