On this page, you can add a blur effect to the uploaded image.
The blur type is called "Gaussian blur" in technical terms.

If you strongly blur a photo of light such as car headlights or neon lights,
or a colorful photo like colored pencils lined up, it will look like an abstract painting.
That will be useful for creating an gradation image as a background under some text.

Supported file formats are JPEG, PNG, GIF, and Heic extensions.