A Comprehensive Exploration of Computer Vision: Past, Present, and Future (Part 3)

Swanand Katdare
3 min readAug 16, 2023

--

Photo by Conor Luddy on Unsplash

The Pre-Deep Learning Era: Feature Extraction Methods: Edges, Corners, Textures

Welcome back to our journey through the evolution of computer vision! In this part of our blog, we’re going to explore the fascinating era before deep learning took center stage. This period was marked by creative problem-solving and the development of ingenious methods to help computers understand images. Let’s dive into the world of feature extraction, template matching, and the challenges that were faced during this era.

Imagine you’re looking at a picture of a cat. What are the important things that your brain focuses on to recognize it as a cat? Maybe you notice its pointy ears, its whiskers, and its shiny eyes. In computer vision, these important visual elements are known as “features.” During the pre-deep learning era, computer scientists realized that by extracting these features, they could help computers recognize objects and patterns in images.

Edges and Corners:
One of the earliest methods used to identify features in images was edge detection. Just like tracing the outline of an object, computers could identify areas of high contrast, like the edges of a table or the boundary between the sky and a building. These edges acted as cues for the computer to understand the shape of objects.

Corners were another essential feature. Imagine the corner of a book cover or the corner of a building. These points are unique and can help computers identify key points in an image. By detecting corners, computers could better understand the geometry and layout of objects.

Textures:
Texture refers to the repeating patterns or surfaces in an image. For instance, the texture of a tiger’s fur or the grainy texture of sand. Analyzing textures helped computers differentiate between various materials and surfaces.

Template Matching and Handcrafted Features:
Template matching was a clever technique used during this era. It involved comparing a part of an image (a template) with different regions of a larger image. If the template closely matched a region, the computer could identify an object.

Handcrafted features were carefully designed by researchers to capture specific characteristics of objects. For example, if you wanted to recognize faces, you’d develop features that highlighted the eyes, nose, and mouth. These features were then used to train computers to recognize patterns.

Challenges Faced: Lighting Conditions, Variations, Computational Limitations
Imagine trying to recognize an object in a photo taken during the day versus the same object photographed at night. The lighting conditions can dramatically change how an object looks. Computers during the pre-deep learning era struggled with these variations. A simple shift in lighting could lead to misinterpretation.

Objects aren’t always seen from the same angle or in the same size. Humans can still recognize a car whether it’s close or far, but computers struggled with this. Variations in size, rotation, and perspective posed significant challenges for early computer vision systems.

Remember, computers of this era were not as powerful as today’s devices. Processing images, especially large ones, was a slow and resource-intensive task. This limited the complexity of algorithms and the size of datasets that could be used for training.

The pre-deep learning era was a time of ingenuity and creativity. Computer scientists laid the foundation for modern computer vision by developing methods to extract crucial features from images. They used techniques like edge and corner detection to help computers understand shapes, and they designed handcrafted features to identify patterns. However, this era also highlighted the challenges posed by variations in lighting and size, as well as the limitations of computational resources. Little did they know that their hard work would set the stage for the revolutionary advancements that were just around the corner: the era of deep learning. So stay tuned as we continue our journey through the evolution of computer vision!

Next blog A Comprehensive Exploration of Computer Vision: Past, Present, and Future (Part 4)

Don’t forget to give us your 👏 !

--

--