Patent ID: RE43686

Claim:
An encoding method, comprising the steps of: receiving an input video signal; selectively encoding at least a portion of said input video signal by intra-frame encoding or predictive encoding to generate first encoded data, said predictive encoding including forward predictive encoding and backward predictive encoding; transform encoding said first encoded data to generate first coefficient data; quantizing said first coefficient data by a fixed step size; variable length encoding said first quantized data to generate a first bit stream; determining an encoding rate of said first bit stream every GOP as a function of a data quantity of intra-frame and forward-predictive encoded pictures only in the GOP; selectively encoding said input video signal by intra-frame or predictive encoding to generate second encoded data; transform encoding said second encoded data to generate second coefficient data; setting a variable step size according to the encoding rate determined every GOP; quantizing said second coefficient data by said variable step size; variable length encoding said second quantized data to generate a second bit stream; and outputting said second bit stream.