AI processes and analyzes images through a combination of data preprocessing, feature extraction, and pattern recognition using neural networks. The most common approach involves convolutional neural networks (CNNs), which are designed to handle grid-like data such as pixels in an image. The process starts by converting the image into numerical data, typically a 3D array representing height, width, and color channels (e.g., RGB). Preprocessing steps like resizing, normalization (scaling pixel values to 0-1), or grayscale conversion simplify the input for the model.
Feature extraction is the core step where the AI identifies meaningful patterns. CNNs use convolutional layers to apply filters that detect edges, textures, or shapes. For example, a filter might highlight vertical edges in a cat image, while deeper layers combine these edges into higher-level features like ears or fur. Pooling layers reduce spatial dimensions, making the model more efficient and translation-invariant. Tools like TensorFlow or PyTorch provide prebuilt layers (e.g., Conv2D, MaxPooling2D) to implement this. A practical example is how a model trained on the MNIST dataset learns to recognize handwritten digits by isolating strokes and curves.
Finally, the extracted features are analyzed for tasks like classification, object detection, or segmentation. A fully connected layer maps features to output classes (e.g., labeling an image as “dog”). For object detection, architectures like YOLO divide the image into grids and predict bounding boxes and class probabilities. Developers can fine-tune pre-trained models (ResNet, EfficientNet) using transfer learning, adapting them to specific datasets. Challenges include handling computational costs (training on GPUs/TPUs) and avoiding overfitting with techniques like data augmentation (rotating, flipping images). For instance, a medical imaging model might use dropout layers and augmented X-rays to improve generalization. The entire pipeline relies on iterative optimization via backpropagation, adjusting weights to minimize prediction errors.