Picture signal coding apparatus
Patent 4205341 Issued on May 27, 1980. Estimated Expiration Date: 
November 14, 1998. 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.
November 14, 1998. 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 References 3462547 3582887 3723649 3737854 3869698 Pattern preliminary processing system Analog-digital converter with variable threshold levels Patent #: 4064484 InventorsAssigneeApplicationNo. 05/960541 filed on 11/14/1978US Classes:375/240.24, Block coding382/270Variable threshold, gain, or slice levelExaminersPrimary: Britton, Howard W.Assistant: Coles, Edward L. Attorney, Agent or FirmInternational ClassH04N 7/26 (20060101)Foreign Application Priority Data1978-01-24 JPAbstractA frame of a gray-scaled picture is divided into blocks, in each of which the mean luminance of picture elements is used as a threshold value for comparison with each picture element signal to classify it into 0 or 1 according to its magnitude to provide a resolution component. From the resolution component and each picture element signal in the block are calculated two gray components; the resolution component and the two gray components are used as coded outputs for each block. The size of each block is changed in accordance with the property of the picture in the portion corresponding to the block. | |
