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 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 favorite 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.

Extracting the original JPEG

Right click on any image in the Bitmap Gallery and select the Save menu option to save the original JPEG back to your file system.


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