8/19/96


The idea is to use a particular color, rather than white, to represent the

presence of an element in an EDS dot map. Is there a way to convert a B/W

digital image to B/color image using either Photoshop or NIH-Image? Thanks

for any input.

Michael Cinibulk

UES, Inc. at

Wright Laboratory

Wright-Patterson AFB, OH

cinibumk@ml.wpafb.af.mil


Hi Mike (and all)

Photoshop should do this fine. Bring the image in (probably as a PICT file)

then change to RGB color under the Mode menu. Go to the Select Menu and choose

"Color Range". You can either select Highlights (for the white pixels) or

"Selected Color" which you can then select (by clicking the cursor on a

representative pixel). One problem, if you have light areas on the gray scale

image that are not part of what you want to change to color, you may have to be

selective about how you do this. Once your pixels are selected, pick a

foreground color you want the pixels to become (use the Picker pallette). Then

choose Fill from the Edit menu and select "foreground color". The program will

then fill everything selected with the color you chose.

If these directions are too confusing, let me know off line and I could walk you

through it on the phone.

I imagine NIH Image will also do something like this but I'm not as familiar

with that program.

Cheers,

John Vetrano

js_vetrano@ccmail.pnl.gov


It may not be easy, but it can be done in PhotoStyler. I suppose PhotoShop

has a similar feature.

It is possible to do an Edit/Fill/Color-Only operation where the chosen

color replaces the gray value. E.g., bright white becomes bright red while

black remains black. However, it is first necessary to convert the image to

a true color (i.e., 24-bit image).

I also was able to convert the white-on-black to color-on-white, but that

took a few more steps which I don't recall off hand. But I could find them

if you need them. I know it involved at least one negative operation.

----------------------------------------------------

Warren E. Straszheim

270 Metals Development, Ames Lab/ISU, Ames IA, 50011

Phone: 515-294-8187 FAX: 515-294-3091

E-Mail: wes@ameslab.gov (or: wesaia@iastate.edu)

http://www.public.iastate.edu/~iprt_info/cfce/ (re: coal)

http://www.public.iastate.edu/~wesaia/marl/ (re: SEM)

coal characterization and processing

electron microscopy, x-ray analysis, image analysis

computer applications


In photoshop, load your image, go to MODE, select INDEXED COLOR . The

program will change the image to indexed mode.

Go to COLOR TABLE and choose CUSTOM. You will see a matrix of 256 color

patches. Click on the top left patch, which represents white. You are

presented with a color square. Pick red (if you like red!) or in the RGB

boxes, set R =255 B=0, G=0. Click OK. Top left square should turn red.

Click OK on table menu. All white areas should turn red. Non X-ray dots

that are red can be edited. Of course if you know in advance you will make

sure no detail in the underlying image goes into white.

Mel Dickson

m.dickson@unsw.edu.au


Although we use the colour lookup tables supplied with our Oxford

Instruments EXL EDS package, I've been playing with Adobe Photoshop to

try and improve some of the LUTs (or palettes as they're referred to in

Photoshop and most other packages).

The method I use for adding colour is to convert the 512x512x16bit (but

only 8 bits contain data) image to "indexed colour mode" and then apply

palettes as required. The advantage of this method is that you can

customise the palette easily, save palettes from images you like (I've

converted the EXL lookup tables to Windows palettes in this way) and it

works really well and is very very easy.

Although Photoshop is expensive, a "lite" version (Photoshop LE) comes

bundled with many scanners so there may be a copy available to you?

If anybody else out there knows of any sources for palettes files I'd

like to know - I'm getting a bit bored with Thermal colour schemes!

Gordon Watt

gwatt@brookes.ac.uk


You can, in principle, do it in NIH-Image but it is tricky - at least, I

can't work out a straightforward way to do it. Also, NIH-Image doesn't like

images that aren't either 8 or 16 bits deep, so you would first have to may

sure your B/W x-ray dot map was converted to 8-bits.

I don't know but guess that it can be done more easily in Photoshop.

However, my preference would be Graphic Converter (I'm assuming you're Mac

based in all this). I would say anyone working with images should have this

application (I have no interest in the programme, or anyone connected with

it). Simply, it allows images to be switched between all sorts of formats,

Mac, PC, and others. There are something like 50 formats it can open and

about 35 it can save. There are a number of useful features but one is

fairly comprehensive LUT editing, including sorting, minimising and direct

editing of any value. I often use it for reducing the size of image files -

read in a 24bit image which only really has useful information in a few

levels, select the levels I want and save as a 4 bit image.

Larry Stoter

LPS@teknesis.demon.co.uk


Actually is is simple in NIH Image, load your grey scaled image then select

"density slice" from the "options" menu. Use the lut tool to slide the top

and bottom of the red up and down until your white pixels are red and all

else is black.

Scott Wight

scott.wight@nist.gov


I am a vender replying to this inquiry. Since you mentioned NIH-Image, I

presume you are interested in viewing your image as a 3D reconstruction.

Our volume visualization software allows full control of color and opacity.

With VoxBlast's Palette Editor, you can asign any value of each of the three

primary color to any portion of the image's histogram. In other words, you

can asign any color to any portion of the image's gray scale.

Furthurmore, you get full control of the image's opacity. This means that

you can make selected portions of the image transparent in order to view a

component inside.

I hope this is helpfull.

Regards

Patrick Guerin

Technical Support Engineer

VayTek, Inc.

Suite 109

305 West Lowe Avenue

Fairfield Iowa 52556

Tel : 515 472-2227

Fax : 515 472-8131

E-Mail :pguerin@vaytek.com


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