Browse Prior Art Database

Sequentially Subsampled Quantized DCT Method for Compression and Reconstruction of Image Data

IP.com Disclosure Number: IPCOM000111283D
Original Publication Date: 1994-Feb-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 2 page(s) / 24K

Publishing Venue

IBM

Related People

Feig, E: AUTHOR [+2]

Abstract

Disclosed is a progressive method of encoding images so that the decoding is improved as more data arrives.

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

Sequentially Subsampled Quantized DCT Method for Compression and
Reconstruction of Image Data

      Disclosed is a progressive method of encoding images so that
the decoding is improved as more data arrives.

      The image is sectioned to 16 times 16 blocks.  An initial
subsequence is obtained by first taking an 8 times 8 decimated
sampling of each block and compressing it via a quantized-DCT scheme.
Decompression is achieved by inverse scaling and inverse DCT followed
by an interpolation.

      The second pass of the transmission chooses a second 8 times 8
decimated sample from the original 16 times 16 block, and compresses
it with a quantized-DCT scheme.  During decompression, the resulting
decompressed image is appended to the first one appropriately, and an
interpolation produces the final image.

      This procedure is repeated twice more; the last step does not
require interpolation, as the full data is there for the
reconstructed image.