Assemblage's diffusion-model steganography (Pulsar) encodes 300–618 bytes per
image vector (mean ± SD by model). Generating one local state takes ~9.5 sec on
an Apple M4 Pro; encoding takes ~4.4 sec; decoding takes ~4.2 sec. Sending a
compressed 300-word message requires only K+h = 4+2 images using the church-256
model, with total send time ~90 sec and receive time ~30 sec. Perceptual-hash
candidate detection runs in ~0.33 ms per image, making scanning all ~150 daily
posts on /r/AIArt take under 1 second.
From 2026-jois-assemblage — Assemblage: Chipping Away at Censorship with Generative Steganography
· Table 2, Table 3, §4.2
· 2026
· Free and Open Communications on the Internet
Implications
Steganographic covert channels based on generative models are computationally feasible for desktop hardware today, but 90-second send latency for a single short message is prohibitive for interactive use; pre-generating offline states in the background reduces this to ~18–28 sec per message in production.
Per-image capacity of ~300–600 bytes limits bulk data transfer; systems that need to smuggle connection bootstrapping credentials (~64–128 bytes) fit comfortably within a single image vector, making this viable for rendezvous channel bootstrapping rather than full-tunnel data transfer.