What is Rasterize in Illustrator and When To Do It?

Taking a vector image and converting it to a raster image is called rasterization. Raster images are made up of pixels, dots, and lines that are combined and displayed together to form an image. Rendering 3D models with rasterization is common, as it is faster than other rendering methods. Likewise, raster images are often used on websites.

Rasterizing converts the image from vector to raster (also called bitmap) format. Now let's focus on answering the question, “What is the purpose of rasterizing our image?”

Raster Images in Illustrator

Adobe Illustrator allows us to edit and create a wide range of graphics and images. It's specifically created for vector images that can be scaled and used at any size. For example, you can design a vector logo in Illustrator and use it for a small business card or a massive billboard, and it will remain crisp and clear at any size.

You can also use Illustrator to convert a vector image into a raster image. This may be useful in some cases when you have a very specific purpose for the file and the vector capabilities (unlimited scaling) are not needed. Raster files benefit from some advanced editing possibilities that do not work as well with vectors. Additionally, a raster or bitmap file format may be needed to open the file in another program.

Although there are many different software applications for rasterizing an image, Illustrator has a greater variety of options than most. Adobe Illustrator has a very friendly user interface, and it may create manageable-sized files.

Rasterizing images in Adobe Illustrator is carried out so vectors can be rasterized and opened in applications that do not work with vector images. Now, let's look at the step-by-step way to rasterize an image in Adobe Illustrator.

How to Rasterize in Illustrator

When you have a vector file (for example, .ai, .eps, or.svg file formats) that you want to rasterize in Illustrator, follow these steps.

Step 1:

Use Adobe Illustrator and open the file you'd like to rasterize.

Step 2:

After selecting all the objects you want to rasterize, click the “Object” menu.

Step 3:

Then click on “Rasterize” in the object menu.

Step 4:

After the Rasterize window opens, the color model you want to use can be selected, including CMYK (cyan, magenta, yellow, black) or RGB (red, green, blue). Choose the option that you prefer. Generaly, RGB is appropriate for images that will be viewed on a screen and CMYK is better for files that will be printed.

You can also select the resolution for your image. Remember that you won't be able to increase the resolution without losing clarity after it is rasterized, so be sure to select a resolution that is as large as you may need it.

Choose a background, either white or transparent. If the image may be used on different color backgrounds, choose transparent. For example, if you're creating an icon that may be used on websites with various background colors, you'll want to set a transparent background.

Putting the “anti-aliasing” option to none will give your lines a clean and crisp appearance. Using rasterization would blur the image lines. Finally, click the ”OK” button to rasterize your image permanently.

After Rasterizing the Vector

When you zoom in and view the rasterized image at higher than 100%, you can see the jagged pixelized edges. This is why you want to ensure that you're setting the resolution as higher or higher than you need. You don't want these pixelated edges to be visible in your designs.

Before Rasterizing the Vector

But before rasterizing your image, you cannot see pixels when you zoom in. The edges remain crisp and clear at any size because vector images do not use pixels.

How to Unrasterize

Now, let's look at how to unrasterize in Illustrator. When you rasterize, you cannot undo it unless you save a copy. If you haven't saved the image yet, you can undo whatever you have done with “Ctrl + Z,” but this is only possible if you haven't gone too far. As a result, always be sure to save a vector copy before rasterizing.

If you don't have a vector copy, it's only possible to solve this problem in one way. Image Trace is what we're talking about here. Raster images are converted to vector images using Illustrator's Image Trace functionality.

Image tracing allows you to convert pencil drawings or other raster/bitmap graphics into vector images. Image Trace provides us with specific presets for getting the image we desire. You can unrasterize your image by following these steps

The first step is to open the image in Illustrator
On the control panel, select “Image Trace” and then select the objects you wish to trace.
Choose the “Make” option, which will automatically make Illustrator trace.

Please be aware that this automation function is not perfect. Your raster image traced to create a vector may not be as perfectly clear as you prefer. Again, this is why it's important to always save a vector version before rasterizing.

Final Thoughts on Rasterizing in Illustrator

Once an image is rasterized, it will remain in pixels forever. It's no longer an equation like a vector, but rather a collection of colored squares. Because of this, rasterizing should be considered a commitment.

When you Rasterize any object, you should save a vector copy in case you need it in the future. It's best to keep your object as vector unless you have a specific reason for needing it in vector or bitmap format. Rasterizing in Illustrator is possible when needed, but it's a function that you probably will not use on a regular basis.