An applet is a neat way to run a program from your web browser.
Be patient! The
applet version of ImageJ should open in a separate "ImageJ"
window. With a slow connection, this may take a minute or two. When it
is loaded a popup should appear asking if you trust this
applet. I have
"signed" the ImageJ
applet. If you accept the certificate you can use DStretch on
your own files! If not you can use the sample
images (File->Open Samples). The applet works with the latest
versions of Internet
ImageJ by clicking on the "ImageJ" window's close
Note that ImageJ may require an updated browser or Java
platform If you have
a PC or Linux you can get
the latest Java platform from here.
Sun is changing the Java site faster than I can keep up, hope you can
find the latest JRE.
ImageJ and DStretch will work like an application on your
computer. You can open and save your own files.
Java limits applet memory which will limit the size of
you can open and enhance. If you can't open images or enhancement
mysteriously does nothing suspect memory problems. You set the
applet memory limit by
entering something like
in the Java Plug-in's "Java Applet Runtime Settings" field. Here
amount of memory (in megabytes) allocated to applets. Change this
number according to your computer's resources. On Mac OS X,
the Java Plugin is in Applications/Utilities. On Windows, it is in Control
Panel->Java Control Panel->Java->Java Applet Runtime
Settings. Note: the applet memory limit is separate from the
ImageJ application memory limit. If running ImageJ as an
application use the "ImageJ->Edit->Options->Memory and
Threads" menu item to change memory.
If you can at least load one image then another way to deal with memory
problems is to reduce the image size using Image->Scale (Choose
the defaults). After scaling delete the original and then
run DStretch on the scaled version.
Once ImageJ opens then choose a file to open. You can access
some of my pictograph images by using the
file->”open samples” menu.
There are several images to choose from. Including all the
from the examples. It may take a little while to open.
After you have loaded an image then open DStretch
using the plugins->”DStretch...Run” menu item.
08-16-2007: I have added a Kachina Rockshelter image from my ARARA
presentation to the samples. Red enhancements work well on
CRGB, LRE or the Y Red Enhance values for YXX. YBK and L
Black Enhance help make some charcoal scratches more visible. I have found the new color balance routine to be useful when the
background rock is
reddish. Use it before or after doing a stretch,
Use the Sat button to tame the wild colors you can sometimes get after
DStretch has user
adjustable colorspaces, see below. My experiments with this
feature have produced several colorspaces that I think will be very
useful. I have made these available in the plugin menu.
They are LDS, LRE, YBK, YBR. Try out LDS on San Borjita 3174
or the Catavina cave
image. It often gives truer colors and less jpeg artifacts than
YDS, but unfortunately is slower to calculate. I think LRE will
become an alternative to CRGB on red pigments. It gives less wild
colors, less jpeg artifacts, but like LDS it is slower to
calculate. Try it on the Catavina abstract image. Try
YBK on the
famous "rooted man" from El Vallicito in Baja California near
Mexicali. Another interesting image
is the lion from Santa Gertrudis Norte. A very difficult image to
enhance well, LAB BTN produces a beautiful result. I have also
of a very beautiful human figure from Tulare County. LRE or CRGB
works well on this.
You can create your own
colorspaces. Use the YXX and LXX buttons. The parameter
values that I used to
create LDS, LRE, YBK and YBR are shown there, but you can try your
own. I even have suggested coefficients for Y Red Enhance and L
Black Enhance. If you find a useful colorspace please let me
image from which the Stories on Stone logo was made.
This is image 8, the Green Anthro image.
Bob used DStretch to get that remarkable image from the "Green Anthro"
image, but I am not sure what
settings he used. To get nice enhancements that show the little
sheep on the right use DStretch LDS or YBK. Bob is the person who
suggested decorrelation stretch to me as a possible useful enhancement
technique for rock art. Thanks Bob!
For help in using DStretch look at the Examples
or Help pages