Please incorporate the following components in your main.py Python script. This script should be simple and minimalistic, focusing solely on the essentials needed to start the implementation of the Large Reconstruction Model (LRM) from the paper you provided. Ensure every setting and function is correctly implemented and maintain simplicity wherever possible.

The implementation will include:

Library Imports: Essential libraries like PyTorch and Transformers must be imported. Only include necessary libraries to maintain simplicity.
Image Preprocessing Function: A function to load and preprocess images that will be used as inputs to the model.
Triplane Decoder Class: A basic implementation of the triplane decoder using PyTorch’s transformer modules.
Model Initializations: Initialize the DINO pre-trained model as the image encoder and set up the triplane decoder.
Main Function: A function that orchestrates the loading of an image, processing through the model, and outputs the decoder's response.
Execution Guard: Ensure the script executes the main function only when it is run as the main module.