Lossy/lossless region-of-interest image coding

• US 7,257,266 B2
• Filed: 12/21/2004
• Issued: 08/14/2007
• Est. Priority Date: 03/20/1998
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Electric Corporation, University of Maryland, College Park
• Original Assignee: Mitsubishi Electric Corporation, University of Maryland, College Park
• Inventors: Farvardin, Nariman, Atsumi, Eiji
• Primary Examiner(s): Dang; Duy M.
• Application Number:
  US11/017,121
• Publication Number:
  US 20050141775A1
• Time in Patent Office: 966 Days
• Field of Search: 382/240, 382244-248, 375/240.19, 348/398.1, 348/408.1
• US Class Current: 382/243
• CPC Class Codes: H04N 19/103 Selection of coding mode or of prediction mode
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/17 the unit being an image region, e.g. an object
• CPC Class Codes: H04N 19/192 the adaptation method, adaptation tool or adaptation type being iterative or recursive
• CPC Class Codes: H04N 19/647 using significance based coding, e.g. Embedded Zerotrees of Wavelets [EZW] or Set Partitioning in Hierarchical Trees [SPIHT]

Abstract

A method and apparatus for encoding digital image data wherein region of interest can be specified either before the encoding process has begun or during the encoding process (127), such that the priority of the encoder outputs are modified so as to place more emphasis on the region of interest, therefore increasing the speed and/or increasing the fidelity of the reconstructed region of interest. The system, therefore, enables more effective reconstruction of digital images over communication lines (128).

Claims

1. A method of image compression, said method comprising the steps of:

selecting a region of interest of an image represented by digital image data;

shifting bits of transform coefficients corresponding to the digital image data of the selected image by a predetermined amount, said predetermined amount corresponding to a desired scale-up rate; and

outputting said digital image data corresponding to said shifted bits of transform coefficients being output earlier than the digital image data corresponding to areas outside of the region of interest.