Understanding Pixels
What is a pixel?
A pixel (picture element) is the smallest addressable element in a digital image. Each pixel contains numerical values representing color intensity.
💡 Key Insight
To a computer, images are just arrays of numbers. Understanding this is crucial for deep learning!
R
Red Channel
0-255 values
G
Green Channel
0-255 values
B
Blue Channel
0-255 values
Images as Tensors
Tensor Representation:
• Grayscale Image: 2D tensor (H × W)
• Color Image: 3D tensor (H × W × C)
• Batch of Images: 4D tensor (B × H × W × C)
Common Image Formats:
• RGB: Red, Green, Blue (most common)
• BGR: Blue, Green, Red (OpenCV)
• HSV: Hue, Saturation, Value
• LAB: Lightness, A*, B* (perceptual)