Fixed quality source coder with fixed threshold

Details Fixed quality source coder with fixed threshold Fixed quality source coder with fixed threshold

1994-07-13

1996-07-30

Williams, Howard L.

Coded data generation or conversion

Digital code to digital code converters

Adaptive coding

348414, H03M 730

Patent

active

055415946

ABSTRACT:
A fixed quality source coder receives and performs VQ on an input signal I.sub.D. The signal I.sub.D may be characterized by the number of samples/frame and bits per sample, and may be provided by a traditional source coder. The traditional source coder may include a sample-and-hold (S/H) circuit producing rxs samples/frame and an ADC providing n bits per pixel. In a first embodiment, the number of bits/sample is increased. In the second embodiment, the number of samples/frame is increased. In a third embodiment, both the number of bits/sample and the number of samples/frame are increased. Measurements made in simulations involving the first and second embodiments show that the fixed quality source coder has a smaller data rate, mean absolute error (MAE) and root mean square error (RMSE) than that of the traditional source coder, while maintaining the same or less maximum error. The fixed quality source coder includes an encoder and may also include a decoder. The encoder may include a lossy codec that receives and encodes the signal I.sub.D to provide encoded information to a multiplexer regarding the signal I.sub.D. The lossy codec also decodes the encoded signal to produce a decoded signal I.sub.VQ.sup.-1. A summer receives I.sub.D and I.sub.VQ.sup.-1 and determines an error signal E.sub.R, where E.sub.R may equal I.sub.D -I.sub.VQ.sup.-1. A threshold circuit receives the signal E.sub.R and passes a threshold signal E.sub.T, where a threshold level T may be set to ensure that the maximum error allowed in the encoder is equal to a particular desired maximum error.

REFERENCES:
patent: 4560977 (1985-12-01), Murakami et al.
patent: 4639778 (1987-01-01), Yamaguchi et al.
patent: 4652905 (1987-03-01), Lippel
patent: 4670851 (1987-06-01), Murakami et al.
patent: 4710812 (1987-12-01), Murakami et al.
patent: 4772946 (1988-09-01), Hammer
patent: 4903317 (1990-02-01), Nishihara et al.
patent: 4933762 (1990-06-01), Guichard et al.
patent: 4943855 (1990-07-01), Bheda et al.
patent: 4958225 (1990-09-01), Bi et al.
patent: 5031037 (1991-07-01), Israelsen
patent: 5124791 (1992-06-01), Israelsen et al.
patent: 5172228 (1992-12-01), Israelsen
patent: 5194950 (1993-03-01), Murakami et al.
patent: 5204899 (1993-04-01), Israelsen et al.
patent: 5235418 (1993-08-01), Lucas
patent: 5371544 (1994-12-01), Jacquin et al.
Patent Application Ser. No. 08/180,010, filed Jan. 11, 1994, presently pending, entitled "Method & Apparatus for Data Compression with Reduced Distortion," inventors Richard W. Harris, Paul D. Israelsen, and Scott E. Budge. Note application is a continuation of 07/676,460 and 07/365,990.
Baker, R. L., "Vector Quantization of Digital Images," Doctoral Thesis, Stanford University (1984). (For copy see file 08/180,010).
Jones, D. W., "Application of Splayed Trees to Data Compression," Communication of the ACM, vol. 31, No. 8, pp. 996-1007 (Aug. 1988). (For copy see file 08/180,010).
Storer, J. A., "Data Compression: Methods and Theory," Computer Science Press, pp. 39-128 (1988). (For copy see file 08/180,010).
Ziv, J. and Lempel, A., "A Universal Algorithm for Sequential Data Compression," IEEE Transactions on Information Theory, pp. 337-343 (Jun. 1976). (For copy see file 08/180,010).
Ziv, J., "On Universal Quantization," IEEE Transactions on Information Theory, vol. IT-31, No. 3 (May 1985). (For copy see file 08/180,010).
Linde, Buzo and Gray, "An Algorithm for Vector Quantizer Design," IEEE Transactions On Communications, vol. Com-28. No. 1 (Jan. 1980).
Juang, B. H. and Gray, A. H., Jr., "Multiple Stage Vector Quantization for Speech Coding," ICASSP Proceedings, vol. 1:597-600, Apr. 1982.
Makhoul, J., Roucos, S., and Gish, H., "Vector Quantization in Speech Coding," IEEE Proceedings, vol. 73, No. 11, Nov. 1985, pp. 1551-1588.
Gray, R. M., "Vector Quantization," IEEE ASSP Magazine, Apr. 1984, pp. 4-29.
Elnahas, S. E., et al., "Progressive Coding and Transmission of Digital Diagnostic Pictures," IEEE Trans. on Medical Imaging, Vol. MI-5, No. 2, Jun. 1986, pp. 73-83.
Elnahas, S. E., "Data Compression With Application to Digital Radiology", Ph.D. Dissertation, Washington University, Sever Institute of Technology, Aug. 1984, pp. 56-68.
Venbrux, J., et al., "A VLSI Chip Set for High-Speed Lossless Data Compression," IEEE Transactions on Circuits and Systems For Video Technology, vol. 2, No. 4, Dec. 1992, pp. 381-391.
Wallace, G. K., "The JPEG Still Picture Compression Standard," IEEE Transactions on Consumer Electronics, vol. 38, No. 1, Feb. 1992, pp. xviii-xxxiv.

Affiliated with

Also associated with

Rating

Fixed quality source coder with fixed threshold does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fixed quality source coder with fixed threshold, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fixed quality source coder with fixed threshold will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1662655