Disclosed are systems and methods for determining the logarithmic transfer
function of a plurality of analog signals using digital circuitry
components. The apparatus is a digital crystal video receiver that
includes an analog-to-digital converter and a programmable logic
component that determines the logarithmic transfer function of plurality
of signals. The programmable logic component may include a FPGA,
microprocessor, macroprocessor, combinations of discrete logic
components, etc. The programmable logic component includes memory having
one of a look-up table and an instruction set that enables the
programmable logic component to process or calculate a signal that is
logarithmically proportional to the plurality of signals. The method for
determining the logarithmic transfer function of a plurality of analog
signals comprises converting the plurality of analog signals to a
plurality digital signals and determining the logarithmic transfer
function of the plurality of analog signals via a programmable logic
component.