Reversible embedded wavelet system implementation

• US 6,549,666 B1
• Filed: 11/05/1999
• Issued: 04/15/2003
• Est. Priority Date: 09/21/1994
• Status: Expired due to Fees

• Current Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Inventors: Schwartz, Edward L.
• Primary Examiner(s): Tran, Phuoc
• Application Number:
  US09/435,313
• Time in Patent Office: 1,257 Days
• Field of Search: 382/232, 382/233, 382/234, 382/235, 382/228, 382/244, 382/248, 382/247, 358/1.15, 358/426.05, 358/426.16, 358/1.16, 341/107, 341/51
• US Class Current: 382/233
• CPC Class Codes: G06F 17/148 Wavelet transforms
• CPC Class Codes: G06K 15/02 using printers
• CPC Class Codes: G06K 15/1865 by compressing the rasterized print data
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
• CPC Class Codes: H04N 19/10 using adaptive coding
• CPC Class Codes: H04N 19/102 characterised by the element, parameter or selection affected or controlled by the adaptive coding
• CPC Class Codes: H04N 19/115 Selection of the code volume for a coding unit prior to coding
• CPC Class Codes: H04N 19/12 Selection from among a plurality of transforms or standards, e.g. selection between discrete cosine transform [DCT] and sub-band transform or selection between H.263 and H.264
• CPC Class Codes: H04N 19/122 Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type
• CPC Class Codes: H04N 19/124 Quantisation
• CPC Class Codes: H04N 19/129 Scanning of coding units, e.g. zig-zag scan of transform coefficients or flexible macroblock ordering [FMO]
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/14 Coding unit complexity, e.g. amount of activity or edge presence estimation H04N19/146 takes precedence
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/15 by monitoring actual compressed data size at the memory before deciding storage at the transmission buffer
• CPC Class Codes: H04N 19/156 Availability of hardware or computational resources, e.g. encoding based on power-saving criteria
• CPC Class Codes: H04N 19/162 User input
• CPC Class Codes: H04N 19/167 Position within a video image, e.g. region of interest [ROI]
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/184 : the unit being bits, e.g. of the compressed video stream
• CPC Class Codes: H04N 19/186 : the unit being a colour or a chrominance component
• CPC Class Codes: H04N 19/1883 : the unit relating to sub-band structure, e.g. hierarchical level, directional tree, e.g. low-high [LH], high-low [HL], high-high [HH]
• CPC Class Codes: H04N 19/36 : Scalability techniques involving formatting the layers as a function of picture distortion after decoding, e.g. signal-to-noise [SNR] scalability
• CPC Class Codes: H04N 19/42 : characterised by implementation details or hardware specially adapted for video compression or decompression, e.g. dedicated software implementation H04N19/635 takes precedence
• CPC Class Codes: H04N 19/46 : Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/593 : involving spatial prediction techniques
• CPC Class Codes: H04N 19/60 : using transform coding
• CPC Class Codes: H04N 19/61 : in combination with predictive coding
• CPC Class Codes: H04N 19/635 : characterised by filter definition or implementation details
• CPC Class Codes: H04N 19/647 : using significance based coding, e.g. Embedded Zerotrees of Wavelets [EZW] or Set Partitioning in Hierarchical Trees [SPIHT]
• CPC Class Codes: H04N 19/98 : Adaptive-dynamic-range coding [ADRC]
• CPC Class Codes: H04N 21/6377 : directed to server one-way streaming services wherein the source is controlled by the destination H04L65/613
• CPC Class Codes: H04N 21/658 : Transmission by the client directed to the server

Abstract

A method and apparatus for performing compression and/or decompression is described. In one embodiment, the present invention comprises a system having a buffer, a wavelet transform unit, and a coder. The wavelet transform unit has an input coupled to the buffer to perform a wavelet transform on pixels stored therein and to generate coefficients at an output. The coder is coupled to the wavelet transform unit to code the transformed pixels received from the buffer.

Claims

1. A decompression system comprising:

a band buffer;

a plurality of coding units for coefficients to undergo an inverse transform operation;

at least one coding unit for storing pixels to be output to an output device;

at least one coding unit for pixels corresponding to previously inversed transformed coefficients to be sent to the output device;

a decompressor coupled to the band buffer, wherein the decompressor decompresses compressed data to transformed coefficients, writes the transformed coefficients to the band buffer, reads back transformed coefficients from the band buffer, performs an inverse transform on transformed coefficients read back from the band buffer to generate pixel values and writes pixels values to the band buffer.

2. The decompression system defined in claim 1 wherein the decompressor reads compressed data from a storage area.

3. The decompression system defined in claim 2 wherein the storage are a comprises a hard disk.

4. The decompression system defined in claim 1 further comprising a print engine coupled to the band buffer.

5. A decoder for decoding coded data, said decoder comprising:

at least one bit generator coupled to receive the coded data and to decode the coded data based on a probability estimation, wherein said at least one bit generator generates a decoded bit from a current line;

a probability estimation machine coupled to said at least one bit generator to provide the probability estimate based on the decoded bit from the current line;

a context model coupled to the probability estimation machine to provide a plurality of contexts to the probability estimation machine based on a partial context address, wherein the probability estimation machine selects among the plurality of context based on the decoded bit.

6. The decoder defined in claim 5 further comprising a same address indicator coupled to the probability estimation machine to detect addresses that have already been read indicating that the data is already available in the probability estimation machine, wherein the same address indicator generates an indication to the probability estimation machine indicating that the data is already in a probability estimation machine based on the partial context being addressed.

7. The decoder defined in claim 5 further comprising a plurality of shift registers coupled to the context model to provide the partial context address.

8. The decoder defined in claim 5 further comprising a line buffer coupled to provide a plurality of above lines.