Provided are an image composition apparatus for composing color images with black-and-white images including infrared components, and an image composition method thereof The image composition method includes generating a first image signal with color information and a second image signal including infrared components without color information, dividing the first image signal into a brightness signal and a color signal, composing the brightness signal of the first image signal with a brightness signal of the second image signal to generate a composed brightness signal, and composing the composed brightness signal with the color signal of the first image signal to generate a color image.

A gain modification device (20) includes a plurality of gain modification units (31) whose number of units corresponds to a number of kinds of a plurality of signals input to the plurality of gain modification units, each one of the plurality of gain modification units (31) being configured to modify a gain value used to amplify the plurality of signals, and a plurality of gain reflection control units (44) configured to change a timing at which the gain value is to be switched by the plurality of gain modification units (31) such that the gain value of one of the plurality of signals affecting a signal level of another one of the plurality of signals is switched at a timing different from a timing at which the gain value of the another one of the plurality of signals is switched.

An original image is read as an aggregate of a plurality of pixels in which adjacent pixels have different colors (R, G, and B) in a main scanning direction and in a sub-scanning direction, and the read pixels of the respective colors are stored in a line memory in association with information on relative positions of the pixels with respect to another pixel. Then, the stored pixels are sorted so that pixels having the same color are adjacent to each other, and an abnormal pixel (dust) not present in the original image is detected based on the state of the sorted pixels. With this, the dust not present in the original image is detected without increasing the cost, and the dust is corrected without forming a conspicuous trace of correction.

An image reading apparatus includes a front-side reader, which includes a white LED configured to irradiate an original with light and a CMOS sensor configured to receive light that is reflected by the original. The front-side reader is configured to generate read data that represents a luminance value of an image on the original from the result of receiving light with the CMOS sensor. The image reading apparatus stores, in a non-volatile memory, a condition for determining whether there is a sub-scanning color shift, and uses a sub-scanning color shift detector to determine whether there is a sub-scanning color shift based on the read data obtained from the front-side reader and the condition stored in the non-volatile memory. When there is a sub-scanning color shift, the image reading apparatus corrects the sub-scanning color shift by correcting the read data with a color shift corrector.

An image processing device performing color balancing of a first image and at least a second image is provided. The image processing device comprises a color balancing determination unit and a color balancing calculation unit.

The color balancing determination unit determines a global gain vector (t) comprising at least two gain factors (â.sup.n, â.sup.n+1) of the first and second images by minimizing a cost function based upon reference pixel values of the first and second images. The first and second image reference pixels depict a shared color scene of the two images.

The color balancing calculation unit performs color balancing of the first image based upon the gain factor (â.sup.n) of the first image and to perform a color balancing of the second image based upon the gain factor (â.sup.n+1) of the second image.

An image processing device that acquires an image from an object includes an illuminator having a plurality of light sources, a sensor unit, and a controller. The plurality of light sources irradiates light of respectively different colors onto an object. The sensor unit outputs luminance data for one line obtained by photoelectrically converting light is reflected from the object of that was irradiated by the illuminator onto the object. The controller acquires a random number, and acquires luminance data for one line output by the sensor unit, while causing one light source selected from the plurality of light sources based on the acquired random number to emit light.

By overlapping lighting timings of light sources that emit lights of a plurality of different wavelength bands including a wavelength band of at least a visible light region and an infrared light region, the lights of the plurality of the different wavelength bands including the wavelength band of at least the visible light region and the infrared light region are emitted on a banknote while securing an overlap in timings thereof. Moreover, by using light receiving elements each including a bandpass filter that allows only light of a wavelength range that corresponds to the wavelength band of each of the light sources, received light intensities of the light of the wavelength range that corresponds to the wavelength band of each of the light sources are acquired simultaneously, and image data are formed based on the received light intensity of every acquired wavelength band.

Provided are an image composition apparatus for composing color images with black-and-white images including infrared components, and an image composition method thereof. The image composition method includes generating a first image signal with color information and a second image signal including infrared components without color information, dividing the first image signal into a brightness signal and a color signal, composing the brightness signal of the first image signal with a brightness signal of the second image signal to generate a composed brightness signal, and composing the composed brightness signal with the color signal of the first image signal to generate a color image.

An image processing method includes: extracting a red, green and blue channel image and a white channel image from a target image; determining a first gray-scale component image of the red, green and blue channel image, and determining a second gray-scale component image of the white channel image; determining first decomposed sub-band information of the first gray-scale component image, and determining second decomposed sub-band information of the second gray-scale component image; determining third decomposed sub-band information according to the first decomposed sub-band information and the second decomposed sub-band information; performing image reconstruction according to the third decomposed sub-band information to obtain a third gray-scale component image, and constructing a color image corresponding to the target image according to the third gray-scale component image. An apparatus and storage medium incorporate the image processing method.

An imaging sensor includes multiple light-receiving elements, which are for multiple colors, configured to conduct photoelectric conversion and multiple power supply lines configured to supply a power supply voltage from a power supply source to the light-receiving elements. The light-receiving elements of each of the colors are aligned in one direction. Portions extending between the power supply source and the respective light-receiving elements of the multiple power supply lines are substantially identical in shape on at least a per-color basis.