Abstract: A method for selecting a filter from among a plurality of ordered filters within an inverse dithering system is disclosed. In response to receipt of a number of filter parameters associated with the plurality of ordered filters and a selected portion of a dithered image, a determination is made of the region of support for the plurality of filters from the filter parameters. From these regions of support, a lowest ordered filter having a region of support that excludes an image edge in the selected portion of the dithered image is selected.

Abstract: A method of reconstructing an image from a dithered image. A predefined set of filters having different regions of support is established. Each filter is defined by a number of filter coefficients and an impulse response function which defines the filter response for a region of support outside of which the impulse response is zero. Filters are organized according to indexes and this organization represents the order in which the filters are considered during a filter selection process. The filter selection process selects a filter constrained by the rule that the filter selected must only perform low-pass filtering on a region of support that does not contain edges of an image. Due to the organization of the filter set, the filter selection process first selects the largest filter from the filter set that fits within the region about the current processed pixel. If there is an edge of an image within the support region of the first selected filter, the next smaller filter is selected.

Abstract: A method and apparatus for inverse dithering a dithered image is disclosed. The system includes a plurality of digital filters which are organized according to a preselected order. A selection module enables the selection of one filter from the plurality of filters according to the preselected order to filter a presently selected portion of the dithered image. The selected portion of the dithered image is then processed based upon the selected filter to generate a portion of the inverse dithered image.

Abstract: A method for bit-depth increasing digital data represented by a first number of original bits which are sequentially ordered beginning with a start bit and ending with an end bit. To bit-depth increase the data, in an expanded presentation, the original bits are replicated in the sequential order starting with the start bit to form replication bits. The original bits are appended with a second number of the replication bits to form the expanded presentation of the digital data. The appended replication bits start with the start bit and are in the sequential order of the original bits.