Rate converter and rate conversion method

A rate converter that performs rate conversion for plural kinds of input rates, including:

• an input delay unit that delays inputted data successively by means of plural delay elements that are connected in series;
• a selection unit that selects data delayed by the respective delay elements in the input delay unit, from taps of the plural delay elements, according to each rate of the inputted data, so that input-to-output times from when the data at the plural kinds of rates are inputted to the rate converter to when the data are outputted therefrom are kept constant;
• an interpolation unit that performs interpolation processing for converting the rates of the data selected by the selection unit to be integer-multiplied;
• and
• an output delay unit that adjusts output timing of the data which have been subjected to the interpolation processing in the interpolation unit, by means of at least one delay element.

A rate conversion method for performing rate conversion to plural kinds of input rates including:

• an input delay step of delaying inputted data successively by means of plural delay elements that are connected in series;
• a selection step of selecting data delayed by the plural delay elements from taps of the plural delay elements according to each rate of the inputted data, so that times required to perform the rate conversion for converting the plural kinds of rates of the inputted data to be integer-multiplied, respectively, are kept constant;
• an interpolation step of performing interpolation processing for converting the rates of the data selected in the selection step to be integer-multiplied, respectively;
• and
• an output delay step of adjusting output timing of data after the interpolation processing, by means of at least one delay element.