A blister pack for use with inhalation therapy inhalers comprises an elongate bottom element having an overlying top element defining a plurality of spaced top crowned areas containing powder or liquid medications or drugs. The radiator element is comprised of a homogenous network about a plurality of inter-connected cells thereby forming a gas-permeable metal foam. Compressed output samples for each non-zero input sample can then be determined based on the logarithm of each respective non-zero input sample.