Software for splitting different stamp images

Sir F. A. Rien a écrit :

From Perfection 3200 on, I believe it's part of the TWAIN [driver]
interface.

After a very busy week, I'm now coming back !
I have yet to see if my older Epson Perfection 2580 has it.

Could you also elaborate a little bit on what is exactly this B&W
strip ?

A scanner sets the colorimetry and levels based upon what is included
inside the marching ants [carousel, whatever].

IF you include a strip that is as black [black stock card without the
plastic] and as bright white [hi-brite paper] as you can find, the
scanner will base the upper and lower levels upon those. Then the
stamps [usually less white and less black] will come out looking
'proper' in tone and not 'washed out', too dark, etc.

The strip can be just off to the side, but must form part of the scan
to be 'seen' by the scanner. Crop off later. If you get really picky,
the interface has a 'dropper' that you can click onto the white and
another for the black, to force those to be 'pure'.

Try it with a single stamp. Put the scan area just around the stamp
and look at the scan, then re-scan but including some of a
black/white strip.

I think you'll see the difference, even with just one item. Done on a
whole page, they will all come out looking 'correct'. But you will
have to use PS to separate the individuals.

As I plate the early GB blacks and reds ['star' series] crisp, clear,
balanced scans are important. You can 'wash out the paper to 'white'
as you'll miss the slight markings [guide lines, flaws, etc] that
confirm the plate. Too dark and your measuring is off!

Many thanks for all these detailed informations :
all is very clear now !


All the scans on
philately.ttrr.org
were done with this 'strip' method.

Congratulations for your beautiful site !

I visited nearly all the pages (including the photography ones and
was pleased to know that a "few" years ago, you visited Paris :-)

--
Kind regards,
Pierre Courtiade

On 12/1/2010 8:37 PM, Billns wrote:
On 11/27/2010 1:46 PM, Joshua McGee wrote:
On Nov 27, 4:28 am, Joshua wrote:

My solution is incomplete: It requires one to scan in a non-lossy
(specifically, not JPEG) format; it's dependent on the black being
"pure" in the scan

A solution to this problem just occurred to me -- that is, to get it
to work with JPEG images (by definition, black regions in JPEG files
are not pure.) But I haven't time to write that today; perhaps
tomorrow.

I see that Bill has mentioned a GIMP plugin that does this, too. If
one gets that to work, it might be superior, unless one specifically
wants to run it as a web application, in which case my solution would
seem better.

The goal at the end of this, of course, would be to give anyone here
who wants it a free copy of the software I'm writing.

I've asked Pierre for a couple scans of the sort he wants to segment.
If anyone else wants to submit sample output from his scanner to make
sure it would work with _his_ scanner hardware and software, please
email samples to me. Please scan with a black background (so that
perforations are not cut off) and, ideally (but not necessarily), scan
twice: once as PNG or GIF, and once as JPEG. My address is "joshua",
then the @ sign, then "mcgees.org" (that's obfuscated to evade spam
harvesters and to get it by the newsreaders that would filter out
email addresses.)

(If anyone missed it: a demo of my solution-so-far can be found at
http://mcgees.org/grid-image/)

I'll keep everyone posted.

Cheers,

--
Joshua H. McGee
Los Angeles, California, USA, Earth
http://www.mcgees.org --

Joshua's approach certainly separates images. But does it straighten
them automatically?

Once our Christmas preparations are well in hand, I'll scan some stamps
using TIF instead of JPG to see if that helps. GIMP separates well but
can't seem to straighten the separated stamps consistently.

Bill

I scanned five stamps at 300 dpi instead of the default 200 dpi on my HP
1315 All-In-One, saved the file as a lossless PNG, changed the
background color to true black in Photoshop Elements, then used the
distribute and straighten command to separate the images. My black
background sheet apparently isn't quite true black. All stamps were
straightened. Four of the five stamps looked pretty good, but one still
had perfs partially cut off on two sides. Still, this is a big
improvement over my previous efforts using the JPG format.

Bill

I scanned five stamps at 300 dpi instead of the default 200 dpi on my HP
1315 All-In-One, saved the file as a lossless PNG, changed the background
color to true black in Photoshop Elements, then used the distribute and
straighten command to separate the images. My black background sheet
apparently isn't quite true black. All stamps were straightened. Four of
the five stamps looked pretty good, but one still had perfs partially cut
off on two sides. Still, this is a big improvement over my previous
efforts using the JPG format.

Bill

I opened my Epson Perfection V200 ($299)
I had attached an A4 sheet of black craft paper to lid with blu tak

I inserted 40 stamps on the scanner platen
I did a "preview" scan
I drew a carousel around the 40 stamps

I hit go, and made a cup of tea,
the scanner did 40 passes at 600 dpi
and dropped the scans into My Documents / New Stamp Scans

I opened FREE Google Picasa, used freehand descew, and cropped the images
to a common border around the perforations.

All finished to perfection in about what?....5 minutes.