Method of data compression including compression of video data

• US 20060002613A1
• Filed: 06/30/2005
• Published: 01/05/2006
• Est. Priority Date: 06/30/2004
• Status: Active Grant

• Current Assignee: Comet Technologies USA Inc. (Comet Holding AG)
• Original Assignee: Comet Video Technologies LLC
• Inventors: Novikov, Sergey V., Zurov, Andrey V., Tanchenko, Alexander P.
• Granted Patent: US 7,315,655 B2
• Time in Patent Office: Days
• US Class Current: 382/240
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets
• 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 data processing system includes a subband decomposition of a source signal by encoding of the significant pyramid-type subband representation. While encoding process, M-array is used for initialization of set of arrays S_i (arrays of solution bits), which define the order of creating output data streams. Output data streams contain an encoded significance map and values of (significant) non-zero subband decomposition coefficients adapted for successive quantization and entropy encoding.

Claims

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

representing said data as an array D of wavelet decomposition coefficients, creating a tree map of said coefficients formed with a root node and consequently connected nodes wherein each node except the root node is a descendant of the corresponding ancestor,

creating an array Z which components corresponding to said nodes are equal to 0 if the corresponding coefficient D has positive or zero value and they are equal to 1 if coefficient D has negative value,

creating a set of threshold arrays T_i=T₀/2ⁱ, where T₀ is a basic threshold array, i is a threshold index,

creating an array M whereas the value of M/T₀ ratio for each node is equal to maximum value of D/T₀ ratio among the all descendants of the given node, creating a set of arrays S_i which components are equal to 0 if the corresponding to given node value of array M component is less than the value of threshold array T_i component and equal to 1 if the corresponding value of array M component is equal or more than the value of threshold array T_i component,

creating a set of arrays B_i which components are equal to the whole part of doubled fractional part of |D|/T₀ ratio.

A method of claim 1 further comprising the steps of creating a V-set of vector-arrays V_i including the components of the arrays;

3. A method of claim 1 wherein the values of the components of basic threshold array T₀ are increased twice for each sequent subband.

2. S_i, B_i corresponding to the descendants of the given node, and the components of the array Z_i corresponding to those descendants of the given node which B_i component is equal to 1:

Creating data streams of V, S, B, Z components, for entropy coding procedures of said V, S, B, Z data streams.