Why Word files can become huge when adding images
Are you tired of seeing your Word documents grow in size, seemingly out of control, especially when you add images to them? You're not alone. Many Microsoft Office users have encountered this issue, and it can be incredibly frustrating. In this blog post, we'll demystify two major reasons behind this problem and introduce you to simple solutions to regain control over your file sizes.
Also, our Word add-in will show you why your documents are so big. Join the waitlist to be notified when it's ready!
The Secret Behind Overly Large Word Files
Have you ever been puzzled by a Word document that grows excessively large after adding a few images? This is often due to Microsoft's legacy support features. To ensure compatibility with older software like Word 2007, the application creates multiple iterations of every image you add.
In fact, Word actually stores three distinct versions of each image within your file. Let's examine why this happens and how it impacts your document size.
Shapes with Image Backgrounds
Imagine you want to set a shape with a picture as a background in your Word document. Select your shape, go to the Shape Format tab, and choose ‘Picture…’ to add an image as a background.
Now, let's say you insert a 2 MB image as the background to a shape in a new Word document. You'd expect your file size to be around 2 MB, given that there's no other content. But no, behold your file size ballooning to a whopping 6+ MB! That's the backward compatibility at play.
Grouped Images
Grouping images in Word, a common practice for better content organization, leads to the same issue. You can spot existing grouped images in your documents by right-clicking the image. If you see the ‘Group’ option enabled then the image is a grouped image.
As an example, you add two 2 MB images to a blank Word document and group them together. Boom! Your file size grows disproportionately. You’d expect the file size to be around 4MB but it has gone up to over 12MB!!
What's Really Happening?
To understand what's going on, let's peek inside the 'Shapes with Image Backgrounds' file. When you open it using a tool like 7-Zip, you'll notice that the file ‘document.xml’ is really large and the uncompressed size is nearly 3 MB (7-Zip lists the sizes in bytes. To convert to MB divide by 1,048,576). Additionally, there are two seemingly identical images in the media folder, just with slightly different file extensions.
If I open ‘document xml’ I can see a huge chunk of data within the <mc:FallBack></mc:Fallback> tags which accounts for its explosion in size. This is actually the image but it has been base64 encoded and appears as weird text.
So the content inside the <mc:Fallback> tags is one image and the two identically sized images in the media folder are copies 2 and 3.
The Solution
You might be curious if there's a way to avoid compatibility mode to shrink these inflated files. Unfortunately, you can't configure Word to bypass compatibility mode and just omit that information. However, there is a solution: NXPowerLite Desktop, our Word Compressor, offers a simple one-click way to compress grouped images and shapes with image backgrounds, among many other features.
As a specialized file compressor, NXPowerLite can strip away compatibility elements when your document contains shapes with image backgrounds. This process does more than just eliminate the two extra copies of your image; it also resizes and optimizes the remaining image to perfectly fit the shape. To see the impact, take a look at the example file mentioned earlier, after compressing with NXPowerLite, it sees a huge reduction in size from over 6 MB to just 30 KB!
A quick note that our upcoming Wordwise add-in will show you exactly why your documents are so big. Join the waitlist to be notified when it's ready!
If you've ever been frustrated by file size explosions in your Office documents, don't hesitate to get in touch. We're always eager to solve these problems and enhance NXPowerLite's ability to make your files more manageable.
