Editing Rate–distortion theory (section)

{{Short description|Branch of information theory which provides the theoretical foundations for lossy data compression}}
{{Information theory}}

{{More citations needed|date=March 2012}}

'''Rate–distortion theory''' is a major branch of [[information theory]] which provides the theoretical foundations for [[lossy data compression]]; it addresses the problem of determining the minimal number of bits per symbol, as measured by the rate ''R'', that should be communicated over a channel, so that the source (input signal) can be approximately reconstructed at the receiver (output signal) without exceeding an expected distortion ''D''.