What is Object Detection?
Object detection is a computer vision technique that identifies and locates objects within digital images or videos. It involves the use of deep learning algorithms, such as convolutional neural networks (CNNs), to distinguish between different object classes and determine their bounding boxes. Object detection has numerous applications, including autonomous vehicles, robotics, surveillance, and image recognition.
How does Object Detection work?
Object detection algorithms generally involve the following steps:
Image preprocessing: Images are preprocessed to ensure that they are of the same size and format before being fed into the object detection algorithm.
Feature extraction: Deep learning algorithms, such as CNNs, are used to extract features from the input images. These features are then used to identify patterns and characteristics that differentiate objects from one another.
Region proposal: The algorithm generates candidate regions or bounding boxes that might contain objects. These regions are then fed into the next stage for classification.
Object classification: The features extracted from the candidate regions are used to classify the objects into different categories.
Non-maximum suppression: This step removes overlapping bounding boxes and retains only the boxes with the highest confidence scores.
Some popular Object Detection models
Several object detection models have been developed over the years, including the following:
R-CNN (Region-based Convolutional Neural Networks): R-CNN uses selective search to generate region proposals and then classifies each proposal using a CNN.
Fast R-CNN: Fast R-CNN improves upon the R-CNN model by introducing a technique called Region of Interest (ROI) pooling, which allows the network to reuse the feature maps for each region proposal, thus reducing computational complexity and speeding up the detection process.
Faster R-CNN: Faster R-CNN replaces the selective search in R-CNN with a Region Proposal Network (RPN), further improving the speed and accuracy of object detection.
YOLO (You Only Look Once): YOLO is a real-time object detection model that treats object detection as a single regression problem, predicting bounding boxes and class probabilities directly from the input image in a single pass.
SSD (Single Shot MultiBox Detector): SSD is another real-time object detection model that uses a series of convolutional layers to predict bounding boxes and class probabilities, eliminating the need for a separate region proposal step.