Step 1. Extract features from query image. (.02s £ t £ .25s)
Step 2. Calculate distance from query to key images.
(1ms £ t £ .8ms)
Step
3. Calculate lower bound distances.
(t » 4ms per 1000 images
using 35 keys,
which is about 250,000 images per second.)
Step
4. Return the images with smallest lower bound
distances.