Start by choosing an image

Select a preset or upload your own image to begin DCT analysis.

🧱 High Texture
🌅 Smooth Gradient
📷 Cameraman
⛵ Boat
🐵 Mandrill
Upload Image JPG, PNG – auto-converted to greyscale

Select an 8×8 Block

Tap or click on the image to pick a block for DCT analysis.

DCT Analysis

Adjust the quantization threshold and watch artifacts appear.

Original Block

Quantized DCT Coefficients

Reconstructed Block

Active Coefficients 64 / 64
MSE 0.00

Full Image Reconstruction

Every 8×8 block is DCT-quantized at the current threshold and reconstructed.

Original
Reconstructed
PSNR ∞ dB
Non-Zero Coeffs (total) —