A device for room geometry analysis comprising: a plurality of segments (101-106) built of acoustic metamaterials, each segment (φ, θ) acting as a waveguide with a unique transfer function (B(φ, θ, ω)); and a processor configured to calculate delays (τ(φ, θ)) and respective directions (c(φ, θ)) of mirror sound sources (721-725) by decomposing a sound signal (Ŝ) obtained from a microphone (110) based on the transfer functions (B(φ, θ, ω)) of the segments (101-106) and based on a calibration signal (tsp(t)) emitted by a speaker (420).