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Exporting GIF, PNG or BMP
files
GIF export is the most common and probably the best format for use on the web. GIF images can have
no more than 256 colors, which you might think is a limitation. However, using Xara3D’s advanced
dithering and palette optimization features, you can get near perfect quality images using only 256 colors.
Indeed you'll be surprised at how good GIFs with just 16 colors can be.
For all export formats you have control over not only the number of colors but also whether the image is
dithered and has an optimized palette. These are techniques to improve the image quality while using a
reduced number of colors. For example using only 16 color GIF nearly always produces the smallest file
size, but with no dithering the shading can be poor. By using an optimized palette and diffusion dithering
you can substantially increase the quality of the result.
There are no hard and fast rules as to which combination of export options is best—it depends on the
image and your requirements. Therefore we recommend exporting in a number of different formats to see
which is the best and has the smallest file size. Typical options to try include 16 color with diffusion
dithering, or 256 color with no dithering.
When exporting as a GIF or PNG you have the option of making it interlaced (progressive rendering as
it’s downloaded) and whether the image is transparent. For more information on the available export
options, including help with printing, see export dialog box
.
BMP export formats
Many other Windows programs can import BMP files but often they do not support the full range of
color depths available in Xara3D. For example Adobe Photoshop cannot import High-color (16 bit)
BMPs. This is beyond the control of Xara3D. If you have problems importing BMPs, try a different
color depth.
Additional quality control
If you bought the CD version of Xara3D you will have received a free copy of Webster (or details on
how to obtain it). Webster provides even more advanced color reduction facilities and can be used to
further reduce the size of files by selecting intermediate numbers of colors. To do this, export the image
as a True color 24-bit BMP image and use Webster to color reduce the file to a specific number of
colors.
Also available from Xara is Xara X, an enhanced and updated version of Xara Webster. More details
on Xara X
.
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