Abstract: To provide an authentication system allowing stable determination as to whether a user is a registered user while saving user's trouble, an information processing device capable of data communication with a plurality of image forming apparatuses extracts an image forming apparatus connected to an IC card reader from the plurality of image forming apparatuses, based on reply signals transmitted from the plurality of image forming apparatuses, and transmits user account information of registered users to the extracted image forming apparatus. The image forming apparatus connectable to the IC card reader performs, if it is determined that the IC card reader is connected to the image forming apparatus, the authentication process based on the user account information of registered users received from the information processing device and on the information read by the IC card reader.

Abstract: To provide an authentication system allowing stable determination as to whether a user is a registered user while saving user's trouble, an information processing device capable of data communication with a plurality of image forming apparatuses extracts an image forming apparatus connected to an IC card reader from the plurality of image forming apparatuses, based on reply signals transmitted from the plurality of image forming apparatuses, and transmits user account information of registered users to the extracted image forming apparatus. The image forming apparatus connectable to the IC card reader performs, if it is determined that the IC card reader is connected to the image forming apparatus, the authentication process based on the user account information of registered users received from the information processing device and on the information read by the IC card reader.

Abstract: In color printing, for example, a color image is generally picked up by a color camera, image scanner and is processed by an image processor and a processing result is obtained as a full color image by a color printer. Some color printers use three different color inks of yellow, magenta and cyan and other printers use black in addition to those inks. Black ink is outputted to print a black area of the colored image and allotment of yellow, magenta or cyan inks is formed on at least part of the black area. Allotment and output of each of the color inks onto the black ink is determined by a color matrix table which defines a color ink output rule. The color matrix table also contains matrix elements for not outputting any of the color of inks.

Abstract: An image processing device includes a multipurpose memory which stores intensity information as well as label information and a look-up memory. The output from the multipurpose memory is connected to an address of the look-up table memory and is converted by the look-up table memory. The image processing device operates to select an area in an image without erasing the data of an image to be processed and to change the color at a very high speed.