System and method for compressing and decompressing images
Patent 6282322 Issued on August 28, 2001. Estimated Expiration Date: 
December 3, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 3, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesTransform coding using coefficient prediction techniques Method and apparatus for concealing errors in a digital television Method and apparatus for compensating errors in a transmitted video signal Video coder providing implicit or explicit prediction for image coding and intra coding of video Apparatus and method of inter-block predictive coding/decoding and storage medium storing coded signal Patent #: 6028637 InventorApplicationNo. 207835 filed on 12/03/1998US Classes:382/248, Transform coding375/240.24, Block coding382/251QuantizationExaminersPrimary: Chang, JonAssistant: Wu, Jingge Attorney, Agent or FirmInternational ClassG06K 009/36AbstractThis invention relates to systems and methods for increasing image compression. The systems and methods are improvements applicable to encoder/decoders which compress images by, inter alia, transforming non-overlapping independent blocks of pixels into a frequency domain and then quantizing the resulting frequency domain coefficients. The invention achieves increased compression by predicting low frequency coefficients of a block from, preferably, the average intensities, or zero frequency coefficients, of the block and its adjacent blocks. In an encoder, the low frequency coefficients are predicted, are then subtracted from the actual transform coefficients, and the difference coefficients are transmitted to a decoder. In the decoder, the low frequency coefficients are again predicted, are added to the received difference coefficients, and the resulting actual transform coefficients are used to reconstruct an image.Other References
Field of SearchIMAGE COMPRESSION OR CODINGIncluding details of decompression Predictive coding Transform coding Discrete cosine or sine transform Quantization Involving hybrid transform and difference coding Plural predictors At transmitter Involving difference transmission (e.g., predictive) BANDWIDTH REDUCTION OR EXPANSION Television or motion video signal Block coding Specific decompression process | |
