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Robert Wilson
12-14-2007, 4:01 PM
Hi All,
My wife wants me to make a bunch of xmas ornaments for family members. I need to remove the backgrounds from the various portraits. I would like to attempt to extract just the people from the images. What steps and software do you all use to remove backgrounds from images. I have seen some really nice extractions where foreground image is removed from the background really precisely. How is this done? Specialized tools, lots of time, both? Also, if you could point me to any tutorials I would greatly appreciate it.

Thanks,
Bob Wilson

ps: I have Corel 12 and Adobe CS at my disposal.

Ron Thompson
12-14-2007, 5:19 PM
Robert,

If you want to read some really great tutorials on using CorelDraw you just have to read the CorelDraw Pro newsletter.

The first issue is on-line at http://www.coreldrawpro.com/library/cp-1006.pdf through http://www.coreldrawpro.com/library/cp-1107.pdf

But the one you want to read first is
http://www.coreldrawpro.com/library/cp-607.pdf

Note all the PDF documents are numbered 1006 for Oct 2006 through 1107 for Nov 2007.

Enjoy .....

And I think I paid for a subscription but I'm not sure. It could be free???? At
http://www.coreldrawpro.com

Ron in San Jose

Larry Bratton
12-14-2007, 5:53 PM
Hi All,
My wife wants me to make a bunch of xmas ornaments for family members. I need to remove the backgrounds from the various portraits. I would like to attempt to extract just the people from the images. What steps and software do you all use to remove backgrounds from images. I have seen some really nice extractions where foreground image is removed from the background really precisely. How is this done? Specialized tools, lots of time, both? Also, if you could point me to any tutorials I would greatly appreciate it.

Thanks,
Bob Wilson

ps: I have Corel 12 and Adobe CS at my disposal.
Robert:
What exactly are you doing with the portraits? Their are several methods for removing backgrounds. Are you engraving these? Do you use Photograv? Are the backgrounds a solid color ?

Lee DeRaud
12-14-2007, 7:51 PM
One thing I've had some luck with lately is to shove the image through the VectorMagic site, using the 'photo', and 'high precision' settings.

What you end up with is an EPS file that imports into Corel as a single group. Ungroup that object and start deleting background objects. The advantage is that the VectorMagic algorithms are very good at edge detection, so you can get a nicely clipped subject without having to work pixel-by-pixel in PhotoPaint. Export that to a bitmap and proceed as usual.

My next pass is usually just conversion to grayscale and some contrast/brightness twiddling; the built-in dithering algorithms in the ULS driver are pretty good. Those of you with PhotoGrav probably have your own preferred sequence from this point on.

All of the above assumes there's some contrast/color differential between the background and the subject, and a fairly high-res starting image since there will be some detail loss in the raster/vector conversion.

Larry Bratton
12-14-2007, 10:31 PM
Lee:
Here's another trick I like. I take the image into Photoshop (or Paint). Select all of the background (hopefully it's all the same color) then delete it or make it transparent. If using Photoshop, use the Magic Erase or Background Removal tool.Then re-select and invert. Fill the subject you want to engrave with black, convert to greyscale and then a black and white 1 bit image. Save that as a different file name. Then import that image into Corel Draw and trace as a line drawing. You now have a perfect Powerclip container. Lots cleaner than trying trace it with the bezier tool to get an outline. Import the image you want to engrave and powerclip it into that container. I use this method to make those photo sculptures also. I do this by printing on my wide Canon inkjet and cut them out with the laser after adhering them to acrylic.
I have also found that in Corel, if you open the image that you want to remove the background from in Photopaint, then select the background, invert, copy (Cntl C), then paste it back into Draw (Cntl V) then the white box or background is gone.
Their are other methods too, but just a couple I use frequently.

Lee DeRaud
12-14-2007, 11:27 PM
Select all of the background (hopefully it's all the same color)...For me, that only happens about once every other pass of Halley's Comet. :eek:

George M. Perzel
12-15-2007, 8:20 AM
Hi Bob;
If you have Corel 12 then you have Photopaint. Photopaint has a "magic wand" tool on the toolbar which will allow you to select portions of the image based on color. The tool sensitivity can be adjusted to increase or decrease the color range. Select an area and delete it-then another area, etc. At the end, enlarge the image and use the eraser tool with a small eraser to clean up any residuals.
When you are done, you can select the entire background area and fill it with black- then greyscale and go to Photograv.
Photoshop works the same but seems to be a little easier. The main problem with portraits is trying to retain the wisps of hair to make the head look natural. There is a PS tutorial somewhere on the web showing how to do this-not the simplest task as I remember but effective. Search PS-background-hair.
Best regards;
George
LaserArts

Scott Shepherd
12-15-2007, 11:15 AM
I don't have PhotoShop (only Elements), but found this after George's advice. It looks amazingly good if you have PhotoShop.

http://denmuel.blogspot.com/2007/09/photoshop-hair-masking.html

Scroll down a little and play the video clip. A lot easier than anything I have seen.

Niklas Bjornestal
12-15-2007, 11:24 AM
If you use photoshop it might be useful to use the channel mixer to improve color differences.

Larry Bratton
12-15-2007, 2:37 PM
Hi Bob;
If you have Corel 12 then you have Photopaint. Photopaint has a "magic wand" tool on the toolbar which will allow you to select portions of the image based on color. The tool sensitivity can be adjusted to increase or decrease the color range. Select an area and delete it-then another area, etc. At the end, enlarge the image and use the eraser tool with a small eraser to clean up any residuals.
When you are done, you can select the entire background area and fill it with black- then greyscale and go to Photograv.
Photoshop works the same but seems to be a little easier. The main problem with portraits is trying to retain the wisps of hair to make the head look natural. There is a PS tutorial somewhere on the web showing how to do this-not the simplest task as I remember but effective. Search PS-background-hair.
Best regards;
George
LaserArts
In Photoshop you use the Extract filter. It's about the same as the Corel Photopaint cutout tool. Photoshop Extract has a Smart Highlight feature that follows the contrast and that helps in maintaining those fine details such as hairlines.

Craig Hogarth
12-15-2007, 5:43 PM
I use corel photopaint cutout lab. it's pretty simple, just paint the outline, fill the image you want to keep, preview and clean up simple details.

i prefer photopaint since it works in corel draw making it easier to go back and forth.

Robert Wilson
12-15-2007, 9:13 PM
Well as expected you all have given me a great deal of ideas and techniques. Thank you all very much. Now it is off to try these and see which works best for me.

Thanks again,
Bob Wilson

Ed Maloney
12-16-2007, 9:53 AM
Same as Craig. Just yesterday I used the cutout lab in Paint to create an ornament with a picture of two kids. A few ornaments I did a powerclip and then used the bezier tool to outline an imagine with a hairline to cut it out.

Lisa Walter
12-16-2007, 1:42 PM
One thing I've had some luck with lately is to shove the image through the VectorMagic site, using the 'photo', and 'high precision' settings.

What you end up with is an EPS file that imports into Corel as a single group. Ungroup that object and start deleting background objects. The advantage is that the VectorMagic algorithms are very good at edge detection, so you can get a nicely clipped subject without having to work pixel-by-pixel in PhotoPaint. Export that to a bitmap and proceed as usual.

My next pass is usually just conversion to grayscale and some contrast/brightness twiddling; the built-in dithering algorithms in the ULS driver are pretty good. Those of you with PhotoGrav probably have your own preferred sequence from this point on.

All of the above assumes there's some contrast/color differential between the background and the subject, and a fairly high-res starting image since there will be some detail loss in the raster/vector conversion.


I tried this site today. I ran the picture through on the high precision. The resulting picture looked the same as the original (picture of a cat). I saved it as an eps to the desktop. When I went to the desktop it wasn't there, so I ran the picture through again, again saved it to the desktop and nothing is there.......????? I am not sure what is going wrong.

Lee DeRaud
12-16-2007, 6:22 PM
I tried this site today. I ran the picture through on the high precision. The resulting picture looked the same as the original (picture of a cat). I saved it as an eps to the desktop. When I went to the desktop it wasn't there, so I ran the picture through again, again saved it to the desktop and nothing is there.......????? I am not sure what is going wrong.Dunno what to tell you: I've never tried saving to the desktop, not sure what that does with an EPS file.

Try just downloading/saving the EPS file to a regular directory. Note that you don't need to "run it through" again: it saves the EPS/SVG files on its server until you delete them.

Larry Bratton
12-16-2007, 8:10 PM
I tried this site today. I ran the picture through on the high precision. The resulting picture looked the same as the original (picture of a cat). I saved it as an eps to the desktop. When I went to the desktop it wasn't there, so I ran the picture through again, again saved it to the desktop and nothing is there.......????? I am not sure what is going wrong.
Lisa:
When you save to the desktop, that is a "Shortcut" ordinarily to an executable file. You need to download the file to a folder as an EPS, then locate it via your File Open or Import command in Corel.