A system for frequency-domain scaling for DCT computation. Scale factors
are applied to coefficients during the final steps of composition of
2-point DCTs. The number of multiplications and required precision are
reduced. Fixed values for various scale factors can be computed and
stored prior to executing the DCT so that performance can be improved.
The fixed values are derived by knowing the length of the time-domain
sequence. Some fixed values can be derived independently of the length of
the time-domain sequence. The approach of the invention can also reduce
the number of multiplications to compute the transform, and allow smaller
bit-width sizes by reducing the number of required high-precision
calculations.