| 摘要 |
PROBLEM TO BE SOLVED: To extract information about a hand written character (especially, color information) accurately irrespective of an ambient external light condition.SOLUTION: An image photographing unit 22 photographs a screen projected by a projector. An external light analysis unit 32 detects white balance on the basis of photographing data inputted from the image photographing unit 22. A projection signal generation unit 33 generates a photographing signal for correcting white balance when white balance is out of balance. An object extraction unit 34 extracts an object such as a character and a drawing pattern on a projection surface photographed by the image photographing unit 22 when white balance is within an allowable range. |
