Technique for interpolating a color image for image enlargement or reduction based on look-up tables stored in memory

Claim 1

An apparatus for processing plural image data obtained by photoelectric conversion of an original image, comprising: memory means for storing a plurality of interpolation tables capable of producing interpolation data in accordance with a magnification operation of enlarging or reducing, each of which interpolation tables comprises interpolation data related to, respectively, sets of adjacent ones of said plural image data, wherein said plurality of interpolation tables differ relative to each other as to at least some of the interpolation data therein; and table selection means for selecting one of the plurality of interpolation tables in accordance with the nature of the original image; whereby an original image having the nature of a line drawing causes a different interpolation table to be selected by the table selection means than does an original image having the nature of a photograph.

Claim 2

An apparatus for processing plural image data obtained by photoelectric conversion of an original image, comprising: memory means for storing a plurality of interpolation tables capable of producing interpolation data in accordance with a magnification operation of enlarging or reducing, each of which interpolation tables comprises interpolation data related to, respectively, sets of adjacent ones of said plural image data, wherein said plurality of interpolation tables differ relative to each other as to at least some of the interpolation data therein; and table selection means for selecting one of the plurality of interpolation tables in accordance with the nature of the original image; whereby an original image having the nature of a line drawing causes a different interpolation table to be selected by the table selection means than does an original image having the nature of a photograph.

Claim 3

An apparatus for processing plural image data obtained by photoelectric conversion of an original image, comprising: interpolating means for producing, from an interpolation table, interpolation data related to, respectively, sets of adjacent ones of said plural image data; interpolation selecting means for outputting a selection signal to said interpolating means to select interpolation data in accordance with a magnification operation of enlarging or reducing; said interpolation selecting means comprising; (a) selection data-writing means for storing a plurality of selection signal tables each of which includes data based on a different magnification, and capable of outputting at least part of one of said selection signal tables in response to a designated magnification; and (b) selection signal memory means for storing said at least part of one of said selection signal tables in response to a designated magnification and thus replacing a previously stored such table; wherein said interpolating means receives an output of the selection signal memory means and produces interpolation data in accordance with the selection signal.

Claim 4

An apparatus for processing plural image data obtained by photoelectric conversion of an original image, comprising: interpolating means for producing, from an interpolation table, interpolation data related to, respectively, sets of adjacent ones of said plural image data; interpolation selecting means for outputting a selection signal to said interpolating means to select interpolation data in accordance with a magnification operation of enlarging or reducing; said interpolation selecting means comprising; (a) selection data-writing means for storing a plurality of selection signal tables each of which includes data based on a different magnification, and capable of outputting at least part of one of said selection signal tables in response to a designated magnification; and (b) selection signal memory means for storing said at least part of one of said selection signal tables in response to a designated magnification and thus replacing a previously stored such table; wherein said interpolating means receives an output of the selection signal memory means and produces interpolation data in accordance with the selection signal.

Claim 13

An apparatus for processing color image data obtained for a plurality of original image pixels in accordance with a designated magnification of enlarging or reducing, comprising: image reading means for separating light from said original image into a set of plural color component images, and for photoelectrically converting the set of plural color component images into a set of plural color component signals for each pixel; a first memory means for storing a first look-up table containing a plurality of density data associated, respectively, with a plurality of preselected colors; means for addressing said first memory means with said set of plural color component signals to retrieve from said first look-up table density data associated therewith, respectively; second memory means for storing a second look-up table containing a plurality of interpolation data for interpolating density data corresponding to a plurality of adjacent pixels, said plurality of interpolation data having different values varying for each respective; density data; and interpolation selection means for providing to said second memory means a selection signal corresponding to a designated magnification for retrieving from the second look-up table interpolation data related to a set of inputted density data and the designated magnification.

Claim 14

An apparatus for processing color image data obtained for a plurality of original image pixels in accordance with a designated magnification of enlarging or reducing, comprising: image reading means for separating light from said original image into a set of plural color component images, and for photoelectrically converting the set of plural color component images into a set of plural color component signals for each pixel; a first memory means for storing a first look-up table containing a plurality of density data associated, respectively, with a plurality of preselected colors; means for addressing said first memory means with said set of plural color component signals to retrieve from said first look-up table density data associated therewith, respectively; second memory means for storing a second look-up table containing a plurality of interpolation data for interpolating density data corresponding to a plurality of adjacent pixels, said plurality of interpolation data having different values varying for each respective; density data; and interpolation selection means for providing to said second memory means a selection signal corresponding to a designated magnification for retrieving from the second look-up table interpolation data related to a set of inputted density data and the designated magnification.