Printing system application using J2K

• US 7,227,999 B2
• Filed: 12/12/2002
• Issued: 06/05/2007
• Est. Priority Date: 09/21/1994
• Status: Expired due to Fees

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Schwartz, Edward L.
• Primary Examiner(s): Tran; Phuoc
• Application Number:
  US10/319,086
• Publication Number:
  US 20030138153A1
• Time in Patent Office: 1,636 Days
• Field of Search: 382/232, 382/233, 382/240, 382/248, 382/244, 382/252, 358/1.15
• 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 printing process comprising:

receiving a bit stream of compressed data from a memory, the bitstream being generated by

performing a wavelet transform on information to generate coefficient data,

generating a first codestream using the coefficient data, and

performing entropy coding on the first codestream to generate the bit stream;

performing entropy decoding on the bit stream received from the memory to generate a second codestream;

decompressing the second codestream to generate decompressed data;

performing an inverse wavelet transform of the decompressed data to generate pixel data; and

transmitting the pixel data to a print engine.

2. The process defined in claim 1 wherein

decoding the data occurs after a delay from when receiving the data from the memory begins,

performing the inverse wavelet transforming occurs after the decoding has been completed, and

transmitting the pixel data to the print engine occurs after the inverse transforming is completed.

3. The process defined in claim 1 further comprising performing halftoning after performing the inverse wavelet transform.

4. The process defined in claim 1 further comprising performing dithering after performing the inverse wavelet transform.

5. The process defined in claim 1 further comprising performing error diffusion after performing the inverse wavelet transform.

6. The process defined in claim 1 further comprising performing interpolation after performing the inverse wavelet transform.

7. The process defined in claim 1 further comprising performing smoothing after performing the inverse wavelet transform.

8. The process defined in claim 1 wherein data in the bitstream comprises coding units.

9. A printing process comprising:

receiving data for printing;

outputting first pixel data;

performing a wavelet transform on the first pixel data to generate coefficient data;

creating a first codestream using the coefficient data;

performing entropy coding on the first codestream to generate a bit stream of compressed data;

storing the bit stream in a memory;

outputting the bit stream from the memory;

receiving the bit stream from the memory;

performing entropy decoding on the bit stream received from the memory to generate second codestream containing decoded data;

decompressing the second codestream to create coefficients;

performing an inverse Wavelet transform on the coefficients to create second pixel data; and

transmitting the second pixel data to a print engine.

10. The process defined in claim 9 further comprising storing the first pixel data in a band buffer prior to performing the wavelet transform.

11. The process defined in claim 10 wherein the band buffer is used as workspace memory for one or more of performing a wavelet transform on the first pixel data to generate coefficient data, encoding the coefficient data based on a context to generate encoded data, and performing entropy coding on the encoded data to generate the bit stream.

12. The process defined in claim 9 wherein the bit stream includes coefficient data categorized more significant data and less significant data.

13. The process defined in claim 12 wherein the more significant data is coded without buffering, and the less significant data is buffered in the band buffer and then the data is embedded and written to the memory.

14. The process defined in claim 9 wherein outputting the first pixel data comprises formatting a set of pixel bands and storing the bands in a band buffer.

15. The process defined claim 9 wherein the data for printing is in the form of a display list.

16. The process defined in claim 9 wherein the data for printing is in the form of a page description language.

17. The process defined in claim 16 wherein the page description language is rendered in to a display list.

18. The process defined in claim 9 wherein

performing entropy decoding on data in the compressed bit stream occurs after a delay from when receiving the data from the memory begins,

performing the inverse wavelet transforming occurs after decompressing the encoded data has been completed, and

transmitting the second pixel data to the print engine occurs after inverse transforming has been completed.

19. The process defined in claim 9 further comprising performing halftoning after performing the inverse wavelet transform.

20. The process defined in claim 9 further comprising performing dithering after performing the inverse wavelet transform.

21. The process defined in claim 9 further comprising performing error diffusion after performing the inverse wavelet transform.

22. The process defined in claim 9 further comprising performing interpolation after performing the inverse wavelet transform.

23. The process defined in claim 9 further comprising performing smoothing after performing the inverse wavelet transform.

24. The process defined in claim 9 wherein data in the bitstream comprises coding units.

25. A printer comprising:

a renderer to receive data for printing and output first pixel data in response thereto;

a compressor to compress the first pixel data, the compressor including

a transform filter to perform a wavelet transform on the first pixel data to generate first coefficient data,

a codestream generator to generate a first codestream using the first coefficient data, and

an entropy encoder to perform entropy coding on the first codestream to generate a bit stream of compressed data;

a decompressor to decompress the bit stream into second pixel data, the decompressor including

a first decoder to perform entropy decoding on the bit stream to generate entropy decoded data,

a second decoder coupled to the first decoder to decode the second codestream into second coefficient data, and

an inverse wavelet transform coupled to the second decoder to create second pixel data in response to the second coefficient data;

a first memory coupled to the decompressor to store the second pixel data; and

a print engine coupled to the second memory.

26. The printer defined in claim 25 wherein the first memory is a band buffer and the first and second memories are the same memory.

27. The printer defined in claim 25 further comprising an enhancement block to perform one or more functions on pixels output from the decompressor.

28. The printer defined in claim 27 wherein the one or more functions includes one or more of interpolation, smoothing, error diffusion, halftoning and dithering.

29. The printer defined in claim 25 further comprising a band buffer to store the first pixel data prior to the transform filter performing the wavelet transform.

30. The printer defined in claim 29 wherein the band buffer is used as workspace memory for one or more of performing a wavelet transform with the transform filter on the first pixel data to generate coefficient data, encoding the coefficient data based on a context using an encoder to generate encoded data, and performing entropy coding on the encoded data using an entropy encoder to generate the bit stream.

31. The printer defined in claim 29 wherein the bit stream includes coefficient data categorized more significant data and less significant data.

32. The printer defined in claim 31 wherein the more significant data is coded without buffering, and the less significant data is buffered in the band buffer and then the data is embedded and written to the memory.

33. The printer defined in claim 29 further comprising a band buffer coupled to the renderer, wherein the renderer formats a set of pixel bands and stores the bands in the band buffer.

34. The printer defined claim 29 wherein the data for printing is in the form of a display list.

35. The printer defined in claim 29 wherein the data for printing is in the form of a page description language.

36. The printer defined in claim 35 wherein the page description language is rendered in to a display list.

37. An article of manufacture having one or more computer-readable storage media storing instructions thereon which, when executed by a system, cause the system to:

receive a bit stream of compressed data from a memory, the bitstream being generated by

perform a wavelet transform on pixel data to generate coefficient data,

generate a first codesteam using the coefficient data, and

perform entropy coding on the first codestream to generate the bit stream;

perform entropy decoding on the bit stream received from the memory to generate a second codestream;

decompress the second codestream to generate decompressed data;

perform an inverse wavelet transform of the decompressed data to generate pixel data; and

transmit the pixel data to a print engine.

38. The article of manufacture defined in claim 37 wherein

the entropy decoding the data occurs after a delay from when receiving the data from the memory begins,

performing the inverse wavelet transforming occurs after the decoding has been completed, and

transmitting the pixel data to the print engine occurs after the inverse transforming is completed.

39. The article of manufacture defined in claim 37 further comprising instructions which, when executed by the system, cause the system to perform halftoning after performing the inverse wavelet transform.

40. The article of manufacture defined in claim 37 further comprising instructions which, when executed by the system, cause the system to perform dithering after performing the inverse wavelet transform.

41. The article of manufacture defined in claim 37 further comprising instructions which, when executed by the system, cause the system to perform error diffusion after performing the inverse wavelet transform.

42. The article of manufacture defined in claim 37 further comprising instructions which, when executed by the system, cause the system to perform interpolation after performing the inverse wavelet transform.

43. The article of manufacture defined in claim 37 further comprising instructions which, when executed by the system, cause the system to perform smoothing after performing the inverse wavelet transform.

44. The article of manufacture defined in claim 37 wherein data in the bitstream comprises coding units.