Patent ID: 7548353
Filing Date: 2009-06-16
Classification: H04N

Abstract:
1. An image reading apparatus comprising: a light source unit which comprises a plurality of light sources in a main scanning direction of an original and irradiates the original; a reader which reads the original in a sub-scanning direction based on irradiation by said light source unit and outputs reading information; an original region identifier which determines, in one line of the original, at least one area of black data extending from a corresponding at least one end of the original in the main scanning direction as an original non-existing region and a remaining region outside of the area as the original existing region; and a lighting control unit which, when a subsequent line is to be read by said reader, determines a part within the original non-existing region adjacent to the original existing region as a margin region, and which executes lighting control of the light sources to turn off light sources corresponding to a region of the original non-existing region except for the margin region and to turn on light sources corresponding to the original existing region and the margin region, wherein said lighting control unit executes said lighting control, when one of the end portions of a newly obtained existing region does not spread to the entire preceding margin region on the side of that end portion, to determine new margin regions on both sides to be a predetermined width within the original non-existing regions, and wherein said lighting control unit executes said lighting control, when one of the end portions of a newly obtained existing region spreads to the entire preceding margin region on the side of that end portion, to determine new margin regions on both sides as the entire original non-existing regions.