Patent ID: 6480541
Filing Date: 2002-11-12
Classification: H04N

Abstract:
A method for generating a video sequence at a plurality of different bit rates from an input video signal, the video sequence comprising multiple bitstreams each having a plurality of data organized in a plurality of temporally sequential spatial frames, the method comprising:inputting the video signal to a first interframe coder which interframe codes the input video signal with a first predetermined coarseness of quantization to generate a first interframe coded bitstream having a first bit rate; reconstructing a frame of the video signal from the first interframe coded bitstream to generate a reconstructed frame having a quantization error corresponding to the first predetermined coarseness of quantization; inputting the video signal to a second or an additional interframe coder which interframe codes the input video signal with a second predetermined coarseness of quantization to generate a second interframe or an additionally coded bitstream having a second average bit rate which is different than the first bit rate, such that each of the first and second bitstreams is an independently viewable version of the video signal at a different coarseness of quantization; and inputting the reconstructed frame to the second or the additional interframe coder with the input video signal such that the second interframe or the additionally coded bitstream includes a coded frame based on the reconstructed frame.