Pulse or digital communications – Bandwidth reduction or expansion – Television or motion video signal
Reexamination Certificate
2007-04-10
2007-04-10
An, Shawn S. (Department: 2621)
Pulse or digital communications
Bandwidth reduction or expansion
Television or motion video signal
C375S240290, C375S240250, C375S240260, C375S240160, C382S251000, C382S260000, C382S269000, C382S268000, C382S266000, C382S233000, C348S699000
Reexamination Certificate
active
09541141
ABSTRACT:
A method of post-processing decompressed images includes identification of the direction of an image edge in a pixel block of the image and filtering applied along the boundary of the block in a direction substantially parallel to the detected image edge. Pixels are selected for filtering on the basis of the quantization parameter of the block of which they are members, the relative difference between pixels adjacent to the block boundary, and significant changes value of pixels in a filtering segment. Filtering is applied parallel to the detected edge to protect the sharpness of the edge while reducing or eliminating blocking and ringing artifacts. A method of separately post-processing fields of interlaced video eliminating complications arising from separate compression of the fields is also disclosed.
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An Shawn S.
Chernoff Vilhauer & McClung & Stenzel
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