DEV Community

Cover image for Get Started With Image Classification in Kaggle using Python
Debajyati Dey
Debajyati Dey

Posted on • Originally published at devsunite.com

Get Started With Image Classification in Kaggle using Python

WHAT KAGGLE IS

Kaggle is a fantastic and great platform for enthusiastic Data Science Engineers to cultivate machine learning with a variety of quality datasets.

If you are not already familiar with Kaggle, Kaggle is a Google-owned platform and online community for data scientists and machine learning engineers to compete in data science challenges, find and share datasets, and learn from others in the field. It provides tools like code notebooks, access to datasets, tutorials, and a community to help users develop their skills and build their portfolios by working on real-world problems.

Kaggle hosts many ML competitions that are organized by prestigious organizations with crazy huge prize pools.

So, you can visit kaggle.com anytime, check the platform out and use their notebooks with powerful GPU and easy access to huge datasets.

GETTING STARTED

To get started with image classification on Kaggle, let's walk through a practical example using the Xception model, which is a deep convolutional neural network architecture pretrained on the ImageNet dataset. The Xception model replaces traditional Inception modules with depth-wise separable convolutions, making it highly efficient and effective for image recognition tasks.

This model has been pretrained on over a million images from the ImageNet dataset, enabling it to recognize a vast variety of spatial visual objects.

GET YOUR HANDS DIRTY

Let's begin coding. Because that is the way (practical) you truly understand the process.

Look below to see how you can implement image classification using the powerful 'Xception' model within a Kaggle notebook:

  1. Set Up Your Environment: Open a new Kaggle notebook or load an existing one. Ensure your notebook is configured to use a GPU accelerator for faster training.
  2. Import required libraries:

    import tensorflow as tf
    from tf.keras.applications import Xception
    from tf.keras.preprocessing import image
    from tf.keras.applications.xception import preprocess_input, decode_predictions
    import numpy as np
    
  3. Load the Pretrained Xception Model: Call the Keras Xception constructor to download the Xception model with its ImageNet weights.

    model = Xception(weights='imagenet')
    
  4. Prepare your image: Choose an image file (like any sample_image.jpg) and prepare it for input to the model. You need to resize the image to the required input size (299x299 pixels for Xception) and apply some preprocessing steps.

    img_path = r'/kaggle/input/crab-image.jpg' # Replace with your image path
    I uploaded an image of a Dungeness crab in my kaggle notebook through the input section on the sidebar, U can use any image you want
    img = image.load_img(img_path, target_size=(299, 299))
    x = image.img_to_array(img)
    x = np.expand_dims(x, axis=0)
    x = preprocess_input(x)
    
  5. Make Predictions: Pass the preprocessed image through the model to get predictions.

    predictions = model.predict(x)
    
  6. Decode Predictions: Use the decode_predictions function to convert the model's output probabilities into human-readable labels and confidence scores.

    decoded_predictions = decode_predictions(predictions, top=3)[0]  # Top 3 predictions
    print('Predicted:', decoded_predictions)
    

This is the image that I used for prediction using Xception -
Blog image.

Dungeness Crab

And woo-hoo, look at that,- the correct answer is found in the top 3 predictions -

jupyter notebook output cell

This simple workflow demonstrates how powerful transfer learning can be.

By leveraging the knowledge the Xception model gained from classifying millions of images on ImageNet, you can quickly classify new images with high accuracy, even without fine-tuning the entire model.

This approach is particularly useful when you have limited labeled data for your specific task.

You can always fine-tune the model on your dataset after anytime. You can find [examples]9https://www.kaggle.com/code/kabhinay/pretrained-xception-model) of this process using the Xception model on Kaggle, such as in the Cassava Leaf Disease Classification competition.

Concluding

The fusion of Kaggle’s robust platform and the power of transfer learning with models like Xception opens up endless possibilities for both aspiring and experienced data scientists. Kaggle not only provides the tools, datasets, and computational resources you need, but also fosters a collaborative community where learning and innovation thrive.

By leveraging pretrained models like Xception, you can achieve remarkable results in image classification—even with minimal labeled data. This approach democratizes access to advanced machine learning, allowing you to focus on solving real-world problems rather than building models from scratch.

So, dive into Kaggle, experiment with its notebooks, and explore the vast array of competitions and datasets. Whether you’re fine-tuning a model for a specific task or simply exploring the capabilities of transfer learning, Kaggle is your gateway to turning ideas into impactful solutions. Start your journey today, and let your curiosity drive you toward mastering the art and science of machine learning and computer vision!

Top comments (0)