However, your image looks better if you size the photo yourself in an image-editing program like Adobe Photoshop (one that supports bicubic resampling).
If you use an image that exceeds the maximum, SketchUp automatically downsizes the file using a medium-quality sampling mechanism. That's the maximum size of an image that can be imported into SketchUp.
In the following table, you find an overview of the raster versus vector images that SketchUp supports. You can work with images in an array of file formats. Most of the details about importing images is covered in Creating a 3D Model, but this article outlines all the ways you import and export images and directs you to the pertinent details in other articles. And you can export images to share a model with friends, clients, or colleagues or perhaps in an online portfolio of your work. You can import images to create custom textures that you apply to faces in your 3D model. In SketchUp, images can help your model come to life on-screen.