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Ham Radio 2000
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Ham Radio 2000.iso
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image.txt
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1996-07-19
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8KB
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Image & Less Menus
------------------
These menus contain a variety of functions for modifying
images.
Image Menu
----------
Most of these functions have the ability to perform image
processing operations on an entire image or only part of
an image.
To apply to only part of an image:
1. Pick the "Select" icon (rectangle of dashed
lines) in the paint control box.
2. Place the mouse pointer in the upper left
corner of the region of interest.
3. Press and hold down the left mouse button.
4. Drag the mouse pointer to the lower right
corner of the region of interest.
5. Finally release the mouse button.
6. Pick a function from the Image or Less menu.
Mirror - Reverses left and right.
Invert - Reverses top and bottom.
Rotate - Rotates image by 90 degrees.
Smooth - Applies a low pass filter which blurs the
image slightly
nois redUc - Random Noise Reduction.
nois reduc - Another Random Noise Reduction technique.
Negative - Reverses colors, much like a photographic
negative.
luminance - Converts to B+W image using a weighted
average of Red, Green, and Blue components.
Red to gray - B+W image from Red component only.
Green to gray - B+W image from Green component only.
Blue to gray - B+W image from Blue component only.
Pseudo color - Converts brightness to a color of the
rainbow for an interesting effect.
Fix Scottie - A couple people implementing the Scottie modes
missed a subtle point about the order of the
sync and RGB color components. You will
notice two problems when receiving pictures
from these systems.
(1) The timing relationship between the
vertical sync (VIS) and the horizontal
sync is way off. This will result in
the gray scale header display being torn
up. Several scan lines are required to
get back in step.
(2) The red component is not aligned with
the green and blue components. If an
image contained a white object on a
black background you would see
red shadow
white object
:
white object
cyan shadow
This menu item shifts the red component
down to line up properly with the others.
Pasokon TV is fully compatible with the
original (Robot 1200C) implementation.
A region of the image must be selected before using these three
functions:
Zoom - The selected region is expanded to fill
the entire image.
Shrink - The whole image is shrunk to fit inside the
selected region.
Graph RGB - Plots the red, green, and blue components
of the selected lines.
The final two items are used to combine 4 or 2 separate images
into a single image. Selecting a region first makes no
difference.
4 into 1 - Shrinks four different images to half size and
combines them into one.
When you pick this menu item the mouse cursor
changes to a square with the upper left
quadrant transparent.
Click on one of the thumbnail of the image you
want to appear in the upper left quadrant.
The cursor changes so the upper right quadrant
is transparent. Click on the thumbnail of
the image you want in this quadrant.
Repeat this for two more images.
L+R into 3D - Combines left and right eye views into a
single 3D image for viewing with Red/Blue
glasses.
The cursor changes to a pair of glasses with
a transparent left lense. Click on the
thumbnail for the left eye view.
The cursor changes to a pair of glasses with
a transparent right lense. Click on the
thumbnail for the right eye view.
The resulting image has the red component from
the left eye view and the blue from the right
eye view.
Use this procedure to compose a 3D picture with
a TV camera:
1. Click on thumbnail 1.
2. Digitize image for left eye view.
3. Click on thumbnail 2.
4. Shift TV camera to right for different angle.
5. Digitize image for right eye view.
6. Click on thumbnail 3 for result destination.
7. Pick "L+R into 3D" from Image menu.
8. Click on thumbnail 1 then thumbnail 2.
- - - - - - - - - - - - - - - -
Less Menu
---------
The Less menu items are used to reduce the resolution or number
of colors in an image.
Pasokon TV stores images with 24 bits per pixel which allows
about 16 million different colors.
The red, green, and blue components each have 8 bits. This
allows 256 different intensities for each of red, green, and
blue. 256 x 256 x 256 is about 16 million.
Some people say you can't tell the difference between
32,000 and 16,000,000 colors. Others might say there is a
world of difference. Judge for yourself if your VGA display
adapter displays 16 million colors.
Seven menu items allow you to reduce the number of colors in
the current image. If part of the image is selected, only
that part of the image will be affected and the rest is left
alone. If there is not a region selected, the entire image
is affected.
Bits for Shades of Total
each of R,G,B each colors
------------- --------- --------
7 128 about 2 million
6 64 about 250,000
5 32 32,768
4 16 4,096
3 8 512
2 4 64
1 2 8
The remaining menu items allow you to reduce the resolution
of an image. This is accomplished by replacing groups of
pixels with the average of that group. For example, the
Quarter menu item will divide the image into 4 x 4 groups
of pixels and replace all in each group with the average
of the 16 in that group.
Reduce by Effective
Menu item Factor Resolution
--------- ------ ----------
Half 2 320 x 240
Quarter 4 160 x 120
Eigth 8 80 x 60
Sixteenth 16 40 x 30
This can produce some interesting special effects when applied
to part of an image but not the rest. For example, try
selecting a person's face and picking Eigth to protect his/her
identity.