DCT Space Visualization
Discrete Cosine Transform - the foundation of JPEG compression
Input Pattern
edges
gradient
checkerboard
circle
diagonal
Quality Threshold: 11.3
(6% compression)
High compression
Full quality
Show basis function
How DCT Compression Works
u, v = 0
→ DC component (average brightness)
Low u, v
→ Smooth gradients, important for perception
High u, v
→ Fine details, less visible to humans
JPEG discards high-frequency coefficients (outside the arc) to reduce file size while maintaining visual quality.
DCT Coefficient Colors
Negative
Zero
Positive
Click on DCT grid to explore basis functions