Page 353 - Xara Designer Pro X17

Photo Handling 353

GIF ANIMATION:

• DELAY (the time this frame is left on screen)
• RESTORE: The Animated GIF Restore setting sets what happens between each frame
in an animated GIF. Nothing means no action is taken. Many browsers take this as
meaning the same as the Leave As Is option. Leave As Is displays the frames one on
top of another - this leaves many frames visible in a stack if some are transparent.
Some browsers clear the animation before it loops again, some do not. Background
restores the area covered by the graphic to the background color of the GIF (usually
white). Restore Previous restores the area covered by the frame to what it was before
the frame was displayed. This is interpreted by some browsers to mean that the frame
should be cleared to the background before each frame is displayed and by others to
mean that the frame should be shown on top of the previous frame. As browsers
interpret these values in different ways, you may need to experiment to achieve the
desired result.

Embedded JPEG files

JPEG files are hugely compressed from their original state, being up to 10 times smaller
than the original uncompressed image. In the above example, the original
uncompressed image requires more than 7mb of memory, but as the BITMAP GALLERY
shows, this JPEG file is only 1mb. A very significant reduction. This is why JPEG images
are the standard file type for digital photography and use on the web.

When you drag and drop a JPEG file (or use the "Open" or "Import" menu options) the
JPEG (reduced in size if it was large) is stored in the document, and this is what is saved
in the .xar file when you save your document.

It's important to understand how this differs from other graphics tools, both vector
drawing software and photo editing programs. Other products will typically un-compress
the image and store the un-compressed "raw" image in memory and the native file when
you save to disc. What's more each copy you make is typically a complete copy of the
original raw image, as mentioned above. Make four copies of your photo and save your
file - it will be four times larger. In Xara Designer Pro X the file is no larger, no matter how
many copies you make.

So by embedding the JPEG file instead of saving the un-compressed image, that's a file
size saving of more than 7:1 compared to other graphics editors. The fact that there are
four complete copies of the image means that in this particular case the memory used is
more like 30 times less. So this represents a huge file size (and time) saving over other
graphics tools*.

*This is easy to test. Import a JPEG into your favourite graphics editor, make four copies,
perhaps change each one slightly, to be colored or blurred or rotated. Then save the native file
and compare it against the original JPEG size, and the equivalent .Xar file. A .Xar native file is
about the size of the original JPEG, no matter how many copies of the image are made.