Training SSD on a custom dataset

In the following code, we will train the SSD algorithm to detect the bounding boxes around objects present in images. We will use the truck versus bus object detection task we have been working on:

The following code is available as Training_SSD.ipynb in the Chapter08 folder of this book's GitHub repository - https://tinyurl.com/mcvp-packt The code contains URLs to download data from and is moderately lengthy. We strongly recommend you to execute the notebook in GitHub to reproduce results while you understand the steps to perform and explanation of various code components from text.

1. Download the image dataset and clone the Git repository hosting the code for the model and the other utilities for processing the data:

import os
if not os.path.exists('open-images-bus-trucks'):
    !pip install -q torch_snippets
    !wget --quiet https://www.dropbox.com/s/agmzwk95v96ihic/\
    open-images-bus-trucks.tar.xz
    !tar -xf open-images-bus-trucks.tar...