Why is my file (size) so large?

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Why is my file (size) so large?

Post by martin » 2009-08-26 15:05:29

Most often large file sizes are due to inserted graphics. Nisus Writer always preserves all original image data, even if you resize the image to display smaller on screen. So if you insert a 2MB photo, the size of your Nisus Writer file will grow to include 2MB of image data and more.

How can I reduce the size of my file?
The best thing to do is be aware of how large your images are. If you are inserting many multi-megabyte images in a document, your file will grow in size accordingly. You should resize/resample your image externally before adding it to your Nisus Writer document.

If you don't need to exchange your documents with other applications, you may also consider saving your documents using the file format Nisus Compressed Rich Text (ZRTF). This file format reduces much of the waste in RTF (see below for details on this wastefulness). The drawback is that ZRTF is only supported by Nisus Writer.

If you do need to share your documents with non-Nisus users, consider using the file format Rich Text Format Directory (RTFD). It stores all images as separate files, reducing waste. Unfortunately this format isn't supported outside of Mac OS X, so you won't be able to send your files to Windows users.

How can I check if my file has large images?
The easiest way is to run our image size check macro on your document.

Once you install the macro, you can run it on any open document to see a listing of images in your document, sorted by size. It's very useful in identifying images that are larger than expected.

How does RTF waste disk space when saving images?
RTF wastes disk space in a variety of ways when saving images:

1. RTF does not support all image types natively. When you insert a non-native image (eg: PDF), Nisus Writer will save both the original image data, as well as an "RTF compatible" image, for the benefit of other applications. The drawback is that non-native images are essentially saved twice, which naturally increases the size of your file. To avoid this duplication, consider inserting JPG or PNG images– both formats are natively supported by RTF.

2. RTF does not by default save image data in pure binary form, but uses something called "hexadecimal escaping". While RTF does allow saving an image as binary, not all applications support this feature. To be more compatible, Nisus Writer saves image data using hexadecimal escaping. This increases the size of the image data by nearly double.

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