The invention relates to an apparatus for location of an instrument or appliance having at least one magnet which produces a magnetic moment at right angles to the appliance shaft and can be rotated independently of the instrument or appliance. Image data sets representing the images are input to background setting means and area ratio calculation means calculates a ratio of an area where a chroma value is not smaller than a predetermined threshold value for an entire area of each image. The substance, which could be delivered orally includes but is not limited to peptides, proteins, RNAs, DNAs, chemotherapeutic agents, biologically active agents, plasmids, and other small molecules and compounds. The VCO frequency is divided by a number N to produce a signal having a divided-down frequency. The right edge portion containing all three guide points is cut out from each of the th L and R images to generate L and R guide images which guide a next camera position.