A method and a system for image compression are disclosed. An image is converted to a halftoned image. The one or more halftoned lines in the halftoned image comprise one or more pixels. A first transformed image is generated from the halftoned image based on shifting of the one or more pixels, associated with the one or more halftoned lines in the halftoned image, by a first value. A second transformed image is generated from the first transformed image based on shifting of the one or more pixels, associated with the one or more halftoned lines in the first transformed image, by a second value. Further, a compressed image is generated based on compression of the second transformed image. The compressed image is stored in a storage device. Another method and system for image conversion are disclosed that converts the compressed image back to the first transformed image.

There is provided a recording data generating apparatus that generates recording data used for reproducing a gloss of an image by recording inclined structures on a recording medium, the recording data generating apparatus including: a conversion unit that converts gloss data with a first resolution having an inclined structure as one pixel into inclined structure data representing a combination ratio of a predetermined number of kinds of inclined structures; a halftone processing unit that generates N-value quantization data representing one of the predetermined number of kinds of inclined structures by performing a halftone process of the inclined structure data of each pixel with the first resolution, N being equal to the predetermined number of kinds; and a recording data generating unit that generates recording data used for recording one of the predetermined number of kinds of inclined structures for each pixel with the first resolution based on the quantization data.

A metallic image forming method is a method for forming a metallic image with a metallic ink containing an organic coloring agent capable of exhibiting a metallic color on a recording medium provided with an undercoat layer thereon having a black color or an opposite color to the color of diffused light from the metallic ink. The method includes applying the metallic ink onto the recording medium so as to cover at least part of the undercoat layer.

An image processing apparatus includes a first screen processing unit that performs first screen processing using a first screen angle on a line region of a character, a second screen processing unit that performs second screen processing using a second screen angle on at least an outline region out of the line region, the second screen angle being different from the first screen angle, and a composition unit that performs composition of a processing result of the first screen processing and a processing result of the second screen processing, on at least the outline region out of the line region.

A computational halftoning process determines a halftoned image having halftoned pixel values by processing an array of input pixels. For each input pixel, an array of high-resolution printer coordinates is defined at a higher spatial resolution than the printer resolution, and a coordinate transformation is applied to determine a corresponding array of high-resolution dot coordinates. An array of high-resolution halftoned pixel values is then determined responsive to the code value of the input pixel by addressing a halftone dot function using the array of high-resolution dot coordinates. A halftoned pixel value is then determined by averaging the high-resolution halftoned pixel values.