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| How do I use Lview Pro to create transparent images on my PC? |
LView Pro is a great image manipulation and conversion tool that runs under Windows 3.1. It supports all sorts of image formats and has a ton of handy image editing tools. It's actually easy to create transparent images using LView Pro, once you know where all the pieces are hidden.
![[LView Pro Colormap Dialog]](/htmlguru/images/q1b.gif)
The first step is to make sure your image has been reduced to 256 colors or fewer.
You can do this by selecting Color Depth from the Retouch menu.
In the dialog that pops up (right), select "Palette image" and the desired number
of colors in the final image. Make sure that you do not select "Enable Floyd-Steinberg
Dithering", since this will cause certain solid colors to be converted to
dithered patterns of slightly different colors. If this happens to your background
color, you won't be able to get the desired
transparent effect from multiple colors.
You'll note that this dialog gives you several color depth choices.
The smaller the color depth, the smaller your image, and the faster
the image will download to your users. For this reason, choose the
smallest number of colors that will accurately represent your image.
If the image is black and white, choose "Black & White". If your
image uses only those colors in the default Windows colormap, select
"Windows palette (16 colors)". If there are a specific number of
colors in the image, fewer than 256, use the "Custom number of colors"
entry to allocate just that many entries in the colormap. Finally,
for those images with more than 256 colors (typically JPEG images or
raw input from a color scanner), choose "256 colors". This
choice will combine "close" colors in the image until just 256 colors remain
in the image.
![[LView Pro Background Color Dialog]](/htmlguru/images/q1a.gif)
Once you reduce your image to 256 or fewer colors, you need to tell
LView Pro which of those colors is going to be the transparent color.
For some inexplicable reason, this feature is hidden under the Options
menu. Select Background Color to open a dialog (left) that lets
you select the desired color.
Within this dialog, select the color that corresponds to the background of your image. LView Pro will mask all but that color in your image, making it easy to see if you picked the right color.
Once you've selected the background color, the final step is to save the image in GIF89a format. Select Save As from the File menu and choose "GIF89a" as the desired file format. LView Pro will automatically set the background color you selected to be transparent. You're finished!
In the event that you want to remove the transparent attribute from an image, load it into LView Pro and resave it as a GIF87a image. Since GIF87a format has no provision for transparency, the result will not have a transparent background encoded into the image.
If you don't have LView Pro, you can get it at any of these sites:
For more information on transparency, see section 5.2.1.2, Interlacing and Transparency, and section 12.6, Transparent Images, in HTML: The Definitive Guide.
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