Classifying Image Dataset created using Google Images

Original article was published on Deep Learning on Medium

Classifying Image Dataset created using Google Images

In this blog post, I’m explaining the approach and step-by-step execution of how I created an image dataset by downloading images from Google search and classifying them using the feed-forward neural network using PyTorch.

This project has various sub-components explained in detail below. The complete source code is available in the link is given below.

Creating a dataset

I wanted to build my own custom dataset for this project from scratch so, I didn’t resort to any famous datasets like MNIST or CIFAR10. To download images in bulk from google image search, I used the tutorial from website create a deep learning dataset using Google Images

This is a 4-step process,

  1. Search for required images one-by-one; I chose to download cats and elephants.
  2. Using the javascript code given in the tutorial, extract all the image URLs to a text file.
  3. Run the given python code to download images using the URLs from the file.
  4. Manually validate images for any corrupted files or irrelevant images.

The tutorial provides the code snippets and it’s easy to use. In the codebase downloaded, I found a folder with the images of Santa. I just added those to my dataset. So the objective here is: Classifying cats, elephants and santas!

Unlike MNIST or any standard datasets, the downloaded images are not perfect. These need to be verified, labeled, and organized to make a dataset out of this. The folder structure is a very important step and it might lead to confusion later. Below is the one I used. In the following code snippet, I explored the structure using code.

Sample view of raw images downloaded from google. You can notice images of different sizes, orientations, and some not so clear.

It is a prerequisite to transform, resize, crop, normalize the images for the model to consume it without difficulties. Also, the images are converted into tensors and pushed into a data loader.

Let’s take a look at the refined images and the code following.

Now the dataset is ready and let’s get started with modeling.