Browse Prior Art Database

Adaptive Refresh of Compressed Image Sequences

IP.com Disclosure Number: IPCOM000109159D
Original Publication Date: 1992-Jul-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 1 page(s) / 32K

Publishing Venue

IBM

Related People

Feig, E: AUTHOR [+3]

Abstract

A method is disclosed to encode video sequences. The method allows near random access in a compressed video stream but does not require periodic full frame refreshes.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Adaptive Refresh of Compressed Image Sequences

      A method is disclosed to encode video sequences.  The method
allows near random access in a compressed video stream but does not
require periodic full frame refreshes.

      A parameter N is fixed; each frame is assumed to have M blocks.
The first frame of the entire sequence is coded with an intraframe
technique.  M counters, corresponding to each of the M blocks, are
initialized to 0.  For each of the remaining frames in the sequence,
the encoder predicts the current frame from the previous frame.  If
the prediction error for a particular block is small and the counter
associated with that block is less than N, the encoder increments the
counter associated with that block and indicates that the decoder
should use the prediction to represent that block.  Otherwise, the
counter is set to zero and the block is coded with an intraframe
technique.  With this method, any frame can still be accessed by
decoding N frames, but fewer blocks are encoded with an intraframe
technique.

      Disclosed anonymously.