We propose a compression method for True Random Bit Generators (TRBGs) that exploits pseudo-chaotic systems. The compression scheme requires extremely low-complex hardware circuits for being implemented whereas its theoretical explanation is based on a weaker and more general interpretation of the Shadowing Theory, focusing on probability measures, rather than on single chaotic trajectories. We prove theoretically how to design the overall compression scheme, in order to assure the final entropy of the compressed TRBG to be arbitrarily close to the maximum theoretical limit of 1 bit/time-step