The Arsenal Files 6/The Arsenal Files 6 (Arsenal Computer).ISO/os2/jvw10h.zip/JVWTRNSF.HLP

OS/2 Help File | 1996-02-26 | 37KB | 781 lines

ΓòÉΓòÉΓòÉ 1. Transformations Utility Add on ΓòÉΓòÉΓòÉ

The functions contained in this DLL are designed to work with the JView imaging
system.  You will need to reference JView's main help file for help on controls
that are common to all JView dialogs, such as the colorwell.  This particular
module is provided by:

                                 Crunch Products
                                  P.O. Box 392
                             Berkeley, CA 94701-0392
                                       USA


ΓòÉΓòÉΓòÉ 1.1. Common Controls ΓòÉΓòÉΓòÉ

All functions provided in the transformations utility will have some of the
following controls.  For our purposes a control is considered to be a push
button, a slider, a checkbox, etc.  Their use is fairly straightforward but a
detailed explanation is provided here.

Low Priority  This checkbox is a signal to run the current operation(s) using a
low priority thread.  A basic understanding of how OS/2 works is needed here.
OS/2 is multi-threaded, that is it allows multiple operations to occur
simultaneously.  So for instance, you may have your word processor doing a
spell check at the same time as you are converting a color image to black and
white.  OS/2  doesn't really run both applications at exactly the same time,
rather it spends a few thousandths of a second running one program and then
switches to the other for a few thousandths.  Because we are talking about such
small amounts of time, it appears as if both programs are running
simultaneously.  What the low priority option does is allow you to say  "hey,
run the other program more often than you run this one."  It will make the
other program much snappier.  You can change the priority even while the
process is running, if you change your mind about  which program you are most
interested in.  Something to beware is that sometimes DOS (or Windows) programs
demand such high priority that if you specify low priority, JView will run so
slowly as to be unbearable.  In those instances simply turn low priority off.
Feel free to play, you can do no harm.

Done  This button indicates that you are satisfied with the current state of
the image and are done using the current function.

Cancel.  This button will have two different effects depending upon whether you
are currently applying the function.  If you are applying the function, hitting
cancel will abort that current function application and return the image back
to the state it was in before the function was applied was started.

If the function is not being applied, Cancel will return the image back to the
state it was in before the current function was run at all and the dialog will
close.

Undo  This button will cause the image to be restored one level.  This will
allow you to reverse changes you have made to the image.

GO!  This button will apply the current function to the image.  It can be
undone by either using the Undo button or the Cancel button.

Image  This will switch  focus to the image window and away from the current
dialog.

Preview Mode  This checkbox is only provided on some functions.  Basically,
this will instruct the function in question to do a fast and sloppy job.  The
idea is to get you a quick idea of what the finished product will look like.
You will need to Undo the image after a preview before applying the function
for real.

Realtime Preview is similar in concept to Preview Mode.  It is only available
on some functions.  Realtime applies the function in question onto a miniature
version of the image allowing you to see how various parameters will affect the
image.

It is very important to realize that virtually all the functions provided in
this add on can be applied on parts of the image as well as the entire image.
Simply select that portion of the image you are interested in by using the left
mouse button (with the appropriate selection method - box, ellipse, freehand).
You can also invert the selection region, so that everything EXCEPT the parts
inside the bounding area will be affected.

Menu Commands.  Just like with JView, a popup menu is available by using the
right mouse button (or the M key).  Transformations will use a different set of
commands than are available when a transformation is not active.  These
commands are :

Dialog  The top menu item will bring the current transformation dialog into the
foreground.

Save Image brings up the JView Save Image Dialog.

Copy allows you to copy the image (or parts of the image) to the clipboard in
standard or special formats.

Print will bring up the JView print dialog.

Refresh will repaint the image.

Display Method allows you to choose the desired display method.

Maginify specifies the amount of magnification to apply, it is only valid when
the Display Method is to use sliders.

Selection is identical to the same command structure at the regular popup menu.
The one exception to this is that you can indicate that the selected region
should be Inverted, i.e. the area to be modified is outside the selected region
instead of inside.


ΓòÉΓòÉΓòÉ 1.2. Objects Utility ΓòÉΓòÉΓòÉ

This particular function is designed to operate in conjunction with the Paste
Special function.  Imagine if you will, another dimension...  Sorry. Imagine
that you have just selected an outline of a person from a given image and have
copied (copied special actually) that image to the clipboard.  You now wish to
paste (paste special actually) that person into your current image.  But you
don't just want that person to sit on top of the scene.  You want them to
appear as if they are standing behind a tree that is in the middle of the
image.  To achieve this effect, you would make the tree an object.  Once you
have designated the tree as an object, you can either paste in front of or
behind it.

You can either Add or Delete an object.  To add an object, you first select the
region of the image that you wish to designate as an object (use the left mouse
button to do this).  Next, push the Add button and enter a name for this
object.

 To Delete an object, select the name of the object you wish to delete and push
the Delete button.  Objects will be automatically deleted whenever a new image
is loaded.

You should keep in mind that objects are created with relative positioning in
mind. Thus, if you were to create an object, then resize the image or crop its
size, the object would be positioned relative to the original image, not to the
changed one.


ΓòÉΓòÉΓòÉ 1.3. Acid ΓòÉΓòÉΓòÉ

This function has been described as either transforming your image into a kind
of sixties psychedelic look or as if acid had been spilled on your picture.
Either way you can vary the acid level, but the effect of different values is
hard to predict.


ΓòÉΓòÉΓòÉ 1.4. Blocks ΓòÉΓòÉΓòÉ

Besides blocks, this function could be called reduce resolution. It simply
takes your image and replaces a group of pixels with the color of a single
pixel.  The effect is commonly used on television to hide someone's identity.

Your main variables are the size (in pixels) of the blocks that will be
created.  H will be the horizontal size, while Y will be the vertical size.


ΓòÉΓòÉΓòÉ 1.5. Cone ΓòÉΓòÉΓòÉ

Cone warps the image such that it appears as if the image was stretched to fit
onto the inside (or outside) of a cone while the viewer's perspective is
looking down from above.

The power variable determines how fast the image (or how much of the image)
shifts towards the center.  Higher power cause a greater shift, thus a more
pronounced effect.


ΓòÉΓòÉΓòÉ 1.6. Double Vision ΓòÉΓòÉΓòÉ

Somewhere at sometime you have probably used a shower where the door was made
of distorted glass so that you could make out that a person was in the shower
but interesting details were distorted.  That's pretty much this function.
Size refers to the number of pixels that a given slice will be.  You also get
to orient the distortion vertically or horizontally.


ΓòÉΓòÉΓòÉ 1.7. Filters ΓòÉΓòÉΓòÉ

This dialog allows you to specify a filter (a matrix of values) to be
multiplied with your image.  This is commonly referred to as applying a filter
to the image.


ΓòÉΓòÉΓòÉ 1.7.1. What is a filter? ΓòÉΓòÉΓòÉ

The filtering of an image is also referred to as convolution.  It is the
process of calculating a new value for a pixel based on the old value of the
pixel and the values of the pixel's neighbors. The neighboring pixels
contribute to the new pixels based on some percentage criteria that is
specified in the filter.  The filter is sometimes referred to as the
convolution kernel.

The filter is applied element by element and the results are summed together.
The result of the summation is usually used as the value of the new pixel,
however you have the option of replacing the old pixel, adding to or
subtracting from the old pixel value.  An example will help here.

We are looking at a pixel somewhere in the center of your image. Your filter is
3 x 3, for a total of 9 elements.  (In reality your filters will be 7 x 7, but
the principle is the same here.) The filter is represented by

1 1 1
1 1 1
1 1 1

This filter will be applied at the pixel we are interested in, but because it
is 3 x 3 in size we will also use the values of the pixels that surround our
target pixel.  For our example lets assume the image is grayscale and so each
pixel is represented by a value between 0 and 255.  Our target pixel and its
neighbors then could be

100 150 200
255 149 249
111 222 137

The filter and the image area are then multiplied together and summed.  This is
different than classic matrix multiplication, the multiplication is carried out
without rotating rows or columns.

filter X image = 1 * 100 + 1 * 150 + 1 * 200 + 1 * 255
+ 1 * 149 + 1 * 249 + 1 * 111 + 1 * 222 + 1 * 137 = 1573

Now, we know that the value of our pixel must be in the range 0-255, yet the
result from out filter was 1573.  This is why there is a divisor field in the
filter application dialog.  The divisor is divided into the result of the
filter multiplication.  You can specify any divisor you like, except 0, but the
typical way to come up with a divisor is to sum the values that make up the
filter.  In our example there are 9 elements each with a value of 1, so their
sum is 9.  We will use a divisor of 9 and now the result of the application of
the filter is 1573 / 9 = 174.7778 (which gets rounded to 175) and this value
becomes the new pixel color. All of the above gets repeated for each pixel in
the image.

This may seem confusing and a lot of trouble to go through but filters offer a
very powerful way of manipulating your image.  They can remove noise, add
special effects or enhance and sharpen your image.  Many image analysis books
have sections that go into details about filtering.  For a more detailed
explanation of filtering, find a bookstore with a strong computer section and
look for titles referring to image analysis or manipulations.


ΓòÉΓòÉΓòÉ 1.7.2. The Filter Utility ΓòÉΓòÉΓòÉ

To understand the options in this dialog you must be familiar with the concept
of how a filter is used.  This is outlined in the previous section.

The filter is specified in the group of entry fields located in the upper left
section of the dialog.  Only signed integer values are allowed.  In addition to
the actual filter, two other fields must be specified.  They are the Divisor
and the Offset. You are already familiar with the divisor.  The Offset field is
simply added onto whatever the result of the filter operation yields.  Usually
it is zero, but for some special effects it is useful.

Instead of just using the result of the filter operation as the new pixel
value, you have three options. The result can be used to Replace the old pixel
if the Replace option is highlighted.  Alternatively, either Add or Subtract
can be specified to have the result of the filter added to or subtracted from
the original value.

To further add to the flexibility of this function, you may operate on the RGB
color channels independently by use of the R, G, and B checkboxes.

There are three radio buttons located beneath the filter matrix.  The Normal
option will just apply the matrix as specified in one single pass.  This is the
most typical way the filter is used.

Unsharp Mask is a process that is commonly used in printing to enhance an
image's edges and to bring out lost details. Basically, a low-pass filtered
copy of the image is subtracted from the current image.  You create the
low-pass filtered image by specifying the appropriate matrix.  A good starting
point is one of the Smoothing or Gaussian filters that are supplied with the
dialog.  So, select Unsharp Mask, select a Laplacian filter and let her rip.

The last method of applying a filter is Deconvolution.  This is intended to
restore an image to its intended appearance after image has been subjected to
some sort of deterioration.  That deterioration could be from a lens
distortion, atmospheric problems, a dirty scanner, etc.  The mathematics behind
deconvolution are too complex to explain in this help file.  As the name
implies, Deconvolution is trying to undue a convolution or filter.  What you
need to due is guess what kind of filter best approximates the distortion that
your image has been subjected to.  Deconvolution iteratively subtracts the
effect of that filter from the image.  Because it is iterative, you need to
make multiple passes, something on the order of 4 - 9 is reasonable to start
with.  As an example of how this works, apply a Guassian filter to your image
using the Normal option.  Next select Deconvolution with 5 passes and see how
well your image gets restored.

In addition to the standard buttons, you can Save and Load your own filters.


ΓòÉΓòÉΓòÉ 1.7.3. Built in Filters ΓòÉΓòÉΓòÉ

The following built-in filters are available, a description of the effect is
included for each family.  Each family of filter can have variations based on
the size and direction of the filter. When directions (orientation) are listed,
the nomenclature is North, South, West, East, North West, South West, North
East, South East, Horizontal, and Vertical.  A directional indicator means that
the filter will have a more pronounced effect along the given direction.

For size, the range will be 3x3 to 7x7.  As a rule of thumb, the larger the
filter the more pronounced or "accurate" the effect will be, but the processing
time goes up quickly as size increases.  A 5x5 filter takes almost 3 times more
work than a 3x3 filter and a 7x7 filter is almost twice as intensive as a 5x5.

The built-in filter families are :

   o  Contour filters are used to aid in edge detection.  For instance, coins
      lying on a desk can be more easily discovered after a contour filter is
      used.  These are given as 7x7 filters, reduce the size to increase the
      speed.

   o   Embossing North, South, ...  These filters give the image an embossed
      look, that is as if the image where pressed out of the paper.  The
      directionality (North West vs South East) can cause the emboss to look
      like engraving instead.

   o  Engrave is almost the same filter as Relief.  Examine them both and you
      will notice it is only the placement of the numbers that change.  Engrave
      makes the image appear as if it has been pushed into (engraved upon) some
      paper.  The colors of the image will be lost, making the image look
      similar to grayscale.  You will get the best results if the image if
      first made grayscale.  Try and figure out why one image appears engraved
      while the other looks more like embossing.

   o   Gradient South, North, ...  This is a directional filter used to find
      areas where the changes in pixel intensity are greatest.  These filters
      are particularly sensitive to the size of the filter.  Those listed are
      all based on 3x3 sizes but their quality can be increased by expanding
      them to the full 7x7 size.  Simply duplicate the pattern in the listed
      filter.

   o  Gaussian 3x3, 5x5, 7x7 do an averaging of the neighboring pixels, but
      with a gaussian distribution - the center pixels gets weighted more
      heavily than the neighboring pixels. It produces a blurring effect,
      though not as strong as the Smooth filters.

   o  High Pass Filters  These filters have an effect that is somewhat opposite
      that of the Low Pass Filters.  These tend to make your bright colors
      brighter and you dark colors darker (if only your laundry detergent
      worked as well).  The downside to these filters is an increase in the
      noise of the image.  The filters are arranged strongest to weakest.

   o  Mean Removal  This is a type of High Pass Filter.

   o  Laplacian 3x3, 5x5, North, ...  The Laplacian is a well known mathematic
      operator. When used as a filter it is a type of edge enhancer with the
      advantage that it will highlight edges in all orientations.

   o  Low Pass Filters  These filters all act to cut off high frequency
      components of the image.  They have no effect on areas where colors are
      constant or change very slowly.  They act more aggressively in areas of
      the image where colors are changing rapidly. They are useful in reducing
      noise in the image.  The Smoothing filters listed elsewhere are a subtype
      of these filters.  The filters are arranged strongest to weakest.

   o  Relief or embossing.  Gives the impression that the image has been
      embossed onto a piece of paper.  The colors of the image will be lost,
      making the image look similar to grayscale.  You will get the best
      results if the image if first made grayscale.  See Engrave for
      comparison.

   o  Shift and Difference  These filters are a type of edge enhancement
      filter.  Their purpose is to discern the edges of your image, that is
      areas where there is a change in objects, for instance the outline of a
      person against a blue sky.

   o  Smooth 3x3, 5x5, 7x7 do an averaging on the neighboring pixels.  This
      smoothes the image, but causes a blurring.  The larger the matrix, the
      smoother the result.

   o  Sobel (North, North West, 3x3,...) These filters do a type of edge
      detection.  See Contour filters.


ΓòÉΓòÉΓòÉ 1.8. Fish Eye ΓòÉΓòÉΓòÉ

Arrr ye mates, gather round.  The effect produced is similar to the distortion
that results when you look through the peephole in the door of your home.  The
greater your Fishiness factor, the greater the likelihood you will have lots of
free time on Saturday nights and also the greater the distortion will be.


ΓòÉΓòÉΓòÉ 1.9. Median ΓòÉΓòÉΓòÉ

The median filter is a smoothing filter that is somewhat similar in nature to
the filters that get used in the Filter function.  The definition of median is
that given a group of numbers, find the number that is less than half of the
numbers and also greater than half.  Often it is similar to the average value,
but it is less likely to be influenced by one very large or small number in the
group.  You specify a radius and all those pixels that lie within the radius
are compared to find the median value which is then used as the new value for
the pixel in question.  What the median does for you is eliminate noise from
your image. Imagine that you have a black image with a few specs of white
scattered about. The median value of most groups of pixels would probably be
black and so the white pixels would be removed.

This is extremely computer intensive work.  For example, if you have a 1000 by
1000 pixel image, you have a total of 1,000,000 pixels.  If you were to specify
a radius of 5, then for each pixel in the image, a comparison of 11 by 11 = 121
pixels would have to be made (its 11 because the radius of 5 means that you go
5 pixels to the left and 5 to the right, that makes 10 plus the pixel in
question so 11).  Multiply those together and you get 121,000,000 comparisons.

In addition to the median of the points in question, you can also specify that
the Maximum or Minimum should be searched for.


ΓòÉΓòÉΓòÉ 1.10. Melting ΓòÉΓòÉΓòÉ

This function shifts groups of pixels giving the impression that the image is
melting or that wind is streaking it.  You get to specify the direction that
the melt will occur.

The Strength field will dictate how much melting will occur.


ΓòÉΓòÉΓòÉ 1.11. Mirror ΓòÉΓòÉΓòÉ

Mirroring creates a duplication of the selected areas as if a mirror were held
to the selected section.  The mirror can be placed in 8 different positions: to
the left, right, up, down, diagonally up and left, diagonally up and right,
diagonally down and left, diagonally down and right.  The entire image can be
reflected, except diagonally.  Remember that you select an area by using the
left mouse button.


ΓòÉΓòÉΓòÉ 1.12. Noise ΓòÉΓòÉΓòÉ

Believe it or not, adding noise to an image can often make it look better.
This function adds random bits of noise (random color values) to your image.
The two variables that you control are Frequency and Amplitude.

Frequency controls how much noise is added.  It is a percentage value so 100
means that every pixel will have the chance to get noise.

The compliment of Frequency is Amplitude.  Once a pixel has been chosen to
receive noise, the amount of noise (shifting) is a function of Amplitude.
Since RGB colorspace has a range of 0-255 for each channel, the range of
amplitude is the same.  Amplitude is the possible maximum value that will be
applied.  The actual value is randomly generated and so will vary between 0 and
the indicated Amplitude value.


ΓòÉΓòÉΓòÉ 1.13. Oil Painting ΓòÉΓòÉΓòÉ

This function makes your image look as if it is actually an oil painting. This
function works by doing a histogram (counting the colors used) in the area
around each pixel.  The pixel gets set to the most used color.  The Oiliness
indicates how big a radius should be used to gather the histogram.  A large
radius means lots of comparisons will be needed for the histogram and so the
function will take a long time to run.  Anything above a value of 5 is probably
overkill.

Another option besides this particular effect is to run multiple passes of
filters over your image.  In particular, run a smoothing filter over the image
three or four times.  Then, run the median filter over the image until the
desired results are achieved.  This method is much slower than simply running
oil painting, but it does give more control.


ΓòÉΓòÉΓòÉ 1.14. Polar Coordinates ΓòÉΓòÉΓòÉ

The image you have displayed on your screen is 2 dimensional and is represented
in Cartesian coordinates - meaning each pixel's position is represented by an X
coordinate and a Y coordinate.  Another way of representing a pixel's position
is to use another coordinate system. The one we are interested in is known as
Polar coordinates.  Instead of X and Y defining a point, polar coordinates are
expressed in an angle (called Theta) that is measured from the X axis, and a
Radius which is measured from the origin.  Mathematically, X = Radius x
cos(Theta) and Y = Radius x sin(Theta). This is known as one to one mapping,
every point that is in Cartesian coordinates can be expressed in Polar
coordinates.

So, we know we can convert between Cartesian and Polar coordinates. What this
function does is convert the image coordinates into Polar coordinates, but it
takes the converted values and displays them as if they were Cartesian
coordinates (it also does some scaling to make things stay relatively the same
size).

A side effect of this distortion is that the image will appear to have rotated
-90 degrees or so.  You may wish to rotate the image after the transforms has
taken place.  Pixels outside the area where the coordinate system
transformation takes place (the corners of a bounding rectangle for instance)
get mapped to the indicated Background Color.


ΓòÉΓòÉΓòÉ 1.15. Ripple ΓòÉΓòÉΓòÉ

First you get a bottle of Ripple, then you take your date...  Whoa! Wrong
program there.  Ripple can be visualized in this way : Imagine that your image
is a photograph placed in a pan full of water.  You are looking at the picture
from directly above.  Now, drop a small pebble directly at the center of the
image.  The rippling distortions of the water is what this function will
duplicate.

There are three basic variables to controlling Ripple, and three advanced
features.  The first of the basics is Amplitude.  Amplitude controls how big
the wave formed from dropping your pebble will be.  For those of you familiar
with trigonometry, it will be the amplitude of a sine wave function.

The next variable is Phase.  When you drop the pebble into the water, at the
point where the pebble hits, the water will first be pulled down, and then it
will splash back up.  Phase indicates what is happening at this point.
Mathematically, it is a shift in degrees for the start of a sine wave.

Last comes Wavelength.  As the name implies, this is the number of pixels
between the crest and trough of the wave that results from the pebble drop.
Mathematically, is the is period of the sine wave.  A small value makes lots of
ripples, larger values = fewer ripples.

The advanced options modify the results of the basic variables.  Inner Radius
and End Radius allow you to specify limits on where the ripple will take place.
Normally, the ripple takes place from the center of the image.  Specifying an
Inner Radius will cause all pixels from the origin spanning outward to that
radius to be unaffected.  Note that Phase is still measured relative to the
origin.

End Radius is used in conjunction with Diminishing Magnitude to have the
ripples become less pronounced as you move away from the center of the image.
It has no effect is Diminishing Magnitude is not checked.  When these two are
used, the image will have full Amplitude wave starting at the center of the
image that will reduce to 0 Amplitude (or no ripples) at the End Radius value.


ΓòÉΓòÉΓòÉ 1.16. Rotate ΓòÉΓòÉΓòÉ

Rotation simply rotates the image about its origin the amount specified in the
Angle  The units of the angle are degrees.  If you rotate your image an amount
that is different from 0, 90, 180, -90, or -180 degrees, blank areas will be
created.  They will be filled in with the specified Background Color.

There is one option available, and that is to Antialias the image. Your image
is made up of pixels that are located at integer positions - (0, 0)  (1, 1)
(45, 234) etc. When you rotate your image, say 45 degrees, the point that was
at (5, 0) needs to be shifted to (3.536, 3.536).  The problem is that the
computer cannot understand a point with fractions in it, it must be (3, 3) or
(4, 4).  This rounding causes a blockiness to appear in your image.  The
blockiness is most apparent along edges, where you get a staircase type effect.
Antialiasing blends these edges look more line straight lines.  The price for
this is some blurring and more computer time to process the image.


ΓòÉΓòÉΓòÉ 1.17. Shear ΓòÉΓòÉΓòÉ

Shear is very similar to rotation, but it's as if only half the job was done.
Shearing causes the  image to rotate, but the shifting is constrained to one
axis (X Shear or Y Shear) only. Imagine your image is printed on a rubber
sheet.  You hold the bottom of the image in one hand and the top in the other.
If you keep your hands the same vertical distance apart but move your bottom
hand to the left and the top hand to the right, the effect on your image is
know as shear (in this case X Shear because you are shearing along the
horizontal axis).

Angle is measured in degrees and indicates the amount of shift that will take
place from the given axis.  (X Shear is thus measured from the vertical axis).
Blank spots will open in the background of the image and will be filled with
the color indicated in Background Color. The Antialias option is the same as is
discussed in detail in the Rotation section.


ΓòÉΓòÉΓòÉ 1.18. Shear - Random ΓòÉΓòÉΓòÉ

See Shear for a discussion of what shearing is.  Random Shear randomly moves a
line of the image a distance of one pixel either up, down, left, or right.
Because gaps will be created a Background Color will be used to fill those
voids.


ΓòÉΓòÉΓòÉ 1.19. Slices ΓòÉΓòÉΓòÉ

This function acts as if your took a photograph of your image, cut it into
strips and then put the strips back together in a somewhat random fashion.

You have three parameters to set.  Min Size and Max Size refer to the range of
sizes for the width of the strip that is shifted (or cut using the above
analogy). The actual size is a random number that lies within that range.  Max
Shift places an upper limit on the amount that a give strip can move.  Again,
since the shift is randomly generated the actual shift will vary between zero
and this maximum value.


ΓòÉΓòÉΓòÉ 1.20. Solarize ΓòÉΓòÉΓòÉ

In photography, it was discovered that if you take partially developed film and
expose it to light, the developed portions are unaffected, but the undeveloped
regions turn from positive to negative (they are inverted).  This process is
known as solarization.

On the computer, we have to decide what parts of the image will be treated as
undeveloped.  This where the Threshold value comes in.  Threshold represents
the intensity of the pixel in question and ranges from 0 to 255.  If the
intensity is less than the Threshold value, the pixel is treated as
undeveloped, so the darker tones are considered undeveloped.

When Normal is selected, all pixels below the given Threshold value of
intensity are inverted.  This is fine and good, but to make life more
interesting some variations are added.

Left, Right, Down, and Up create a Threshold value as a function of the
distance from the given axis.  So, Left will have the solarization effect
increasing from as you move along the horizontal axis toward the right edge of
the image.  The other options apply similarly.  Since the threshold value is a
function of position, the value entered in the Threshold spin box is ignored.


ΓòÉΓòÉΓòÉ 1.21. Swirl ΓòÉΓòÉΓòÉ

This effect makes your image look as if someone had twisted the middle.
Another analogy would be that your image was painted on the top of a bowl of
water and you stirred the middle of the bowl.  You control the amount of
twisting (or Rotation).


ΓòÉΓòÉΓòÉ 1.22. Tiles ΓòÉΓòÉΓòÉ

This effect takes your image, cuts it up into itsy bitsy squares and then
somewhat randomly glues the squares back together.  You specify the Tile Size
of the squares that the image will be cut into. These tiles are then randomly
shifted, up to a Max Shift amount before being put back into the image.
Because blank spots will appear in the image, they get filled with the color
specified in Background Color.


ΓòÉΓòÉΓòÉ 1.23. Warp ΓòÉΓòÉΓòÉ

Warping is a way of interactively distorting your image.  It gives you a great
deal of control over just how much and what parts of your image get distorted.
It is easiest to think of warping as acting upon a rubber sheet with your image
printed upon it.  As you push and pull the sheet, so the image will distort.

The heart of warping is defining your control mesh.  This mesh is made up of a
series of control points which define how the image gets distorted.  When you
first start Warp, you are given a total of 4 control points, one at each corner
of your image.  You specify how many control points you want in along the X and
Y axes by changing the value in the appropriate spin boxes.

To aid you in seeing your mesh, you may change the Grid Color that it will be
displayed with.  Additionally, you choose the Fast Grid option. This option
will display the mesh (and changes to the mesh) as fast as possible, but will
sometimes make the mesh difficult to see.  Turning Fast Mesh off will aid
visibility but degrade display speed.  An additional aid in visualizing the
mesh is to enter a value in the Grid Multiplier spin box.  This will add grid
lines to your mesh, but only as a visual aid.  You will not have direct control
over them and they do not affect how the warp is processed.  The Grid
Multiplier is only used if both Peripheral Only and Splines are not selected.

At the highest level, they are two different ways that a warp can be performed,
to Warp In and Warp Out.  To Warp In is probably the more intuitive way to
perceive warping.  You start with your undistorted image as a rectangle.  After
you have created your warp mesh, the image is forced into the outline of the
mesh you have created.  Warping Out does just the reverse.  You start with your
undistorted image and overlay your warp mesh upon it.  All the points that
underlie your warp mesh are then stretched to fit into the rectangle that your
image initially start with.  You are working backwards from Warp In.  Warp Out
does have the advantage that the final image will completely fill your
rectangle.

Aside from Warp In versus Warp Out, you can specify the type of mesh you wish
to work with.  Selecting Peripheral Only means that you will only have control
over the points that lie on the outside edges of your warp mesh.  When the
feature is on, the Grid Multiplier and Fast Grid are ignored.

Splines to creates a mesh based on splines (a type of curve).  The Spline
option places several constraints on your mesh. First, Peripheral Only, Fast
Grid,  and Grid Multiplier are ignored when splines are selected.  Second,
splines must have control points that lie along the outside edges of the image,
these points cannot be brought towards the center of the image.  The net effect
is that the final image will always be rectangular.  Finally, Splines is
strictly a Warp In procedure.

The control mesh is manipulated by use of the left mouse button.  Simply place
the pointer over the control point of interest (the control point is
highlighted) and while keeping the mouse button depressed, drag the point into
the desired position.


ΓòÉΓòÉΓòÉ 1.24. Waves ΓòÉΓòÉΓòÉ

Waves distorts your image by causing it to be displaces along either the
vertical or horizontal axis by an amount that is driven by the trigonometric
sine wave function.  Aside from the orientation of the wave, you specify
Amplitude or height of the wave, the Phase or where does the zero height of the
wave begin, and finally Wavelength which dictates the distance between two
peaks of the wave.

Antialiasing is described in detail elsewhere, but basically it serves to
smooth ragged edges that may result from application of the wave.


ΓòÉΓòÉΓòÉ 1.25. Screen Capture ΓòÉΓòÉΓòÉ

This utility allows you to capture a copy of the screen.  You have several
choices about when the capture will occur.

First, you may select a Time delay.  This method will wait the indicated amount
of time after the sequence has been started, and then the capture will take
place.  Please note that if you intend to have an OS/2 system window active,
this will be the only method for doing the screen capture.  OS/2 windows can be
present for any of the capture methods, but if one will have the focus, then
this is the only allowable method.

The alternative to a timed sequence is to use Hot Keys.  You have three
different key combinations available to choose from.

In all cases the entire screen is captured, you may crop down to the areas of
interest after the capture has occurred.


ΓòÉΓòÉΓòÉ 1.26. Paste Into ΓòÉΓòÉΓòÉ

This feature allows you to paste whatever image is currently in the clipboard
into whatever image currently is being displayed by JView.  Decide how much you
want to scale or rotate the image to be pasted.  Scaling is in percent, so 100
means the current size. Rotation is in degrees.  The Strength attribute tells
how much to blend the items. It is often referred to as an alpha value.  A
value of 100 means the pasted in image will completely cover the area it is
pasted onto.  A value of 50 would take half the image that currently exists,
and half the image that is about to be pasted and adds them together.

The Blend Edges option will take the interface between the current image and
the image being pasted and blend them slightly.  This will make the transition
between images less apparent.

In addition to rotation and scaling, you can  Flip Horizontally or Vertically
the image to be pasted.

Objects are parts of the image that you have already sectioned off.  The
purpose of these are to allow you place the paste image "in between" parts of
the current picture.  For instance let your image be a single palm tree on a
desert landscape.  You wish to paste in an image of a person standing behind
the tree.  You would first create an object of the tree (See Object Utility).
Next you would create your paste image.  Finally you would select Paste Into.
Choose Objects and select the palm tree.  Then complete the paste.  You would
find that your person was pasted behind the palm tree.

Once you have Created the Paste Image (this button just applies the Rotation
and Scaling factors), use the right mouse button to drag the image onto the
main viewing window for positioning.

The Create Paste Image button always operates on the image currently in the
clipboard.  Because of this, each scale or rotation is applied to the image
only once. In contrast, Flipping the image is applied to the paste image
already created and so is lost whenever you hit Create Paste Image.  Understand
that you can do one paste operation and then copy a new image to the clipboard
and then paste this one too.  There is no need to exit between pastes.

Note for users running with 8 bit graphics systems.  Because you can only
display 256 unique colors at one time, the pasting process will often distort
colors when you are aligning the images for pasting.  This happens because each
may contain different colors and so in total exceed the 256 color limit.  Once
the paste is completed the color distortion is removed.


ΓòÉΓòÉΓòÉ 1.26.1. Objects ΓòÉΓòÉΓòÉ

To access this dialog, you will be in the process of pasting one image into
another.  With this dialog, you select those objects, behind which your pasted
image will appear.  The list box which shows the objects you have currently
defined is a little special.  Before we go into it, lets describe what all the
buttons do.

OK signals you're through and the dialog is exited.  Whatever objects you have
selected are used during the paste.

All selects all the objects.

None de-selects all the objects.

Show will show you whatever the currently highlighted object look like.  For
the objects list box, highlighted means that the object in question has the
text and background displayed in inverted colors.  Only one object can be
highlighted at a time and it is done so by clicking on the object name - to the
right of the checkbox.

Delete will delete whichever object is highlighted.

Add allows you to create (add) a new object.  You will need to have selected
the appropriate region with a cropping outline and you need to type in a name.

Selecting vs Highlighting  As mentioned, an object is highlighted when the
entire line is drawn in inverted colors.  To highlight an object, click on the
appropriate line, away from the check box (the extreme left of the line).  In
order to select an object (for use in pasting) you need to check the checkbox
located to the left of the object's name.  You check (or uncheck) the box by
clicking it in the center.