1. An imaging parameter acquisition apparatus connected via a network to a client system equipped with a display apparatus and imaging apparatuses, said imaging parameter acquisition apparatus comprising: a movement instruction unit that sends a moving instruction message to the client system, the moving instruction message instructs to move the display apparatus so that each of the imaging apparatuses, which acquire an image for creating a three-dimensional model, can shoot a screen of the display apparatus; a display instruction unit that sends a display instruction message to the client system to which the moving instruction message is sent, the display instruction message instructs to display a pattern image for imaging parameter computation on the screen of the display apparatus; an imaging instruction unit that sends a imaging instruction message to the client system to which the display instruction message is sent, the imaging instruction message instructs (a) to make the imaging apparatuses shooting the screen of the display apparatus and (b) to send the images shot by the imaging apparatuses; an image acquisition unit that acquires the images which are send by the client system in response to the imaging instruction message; and an imaging parameter acquisition unit that acquires imaging parameters of each of the imaging apparatuses, which acquire the image for creating the three-dimensional model, based on the images acquired by the image acquisition unit.