1. An image processing apparatus, comprising: a labeling unit adapted to execute a labeling process for specifying at least one object region contained in a received image; and a vectorizing unit adapted to generate vector data on the basis of a result of labeling by said labeling unit; wherein, if said labeling unit determines that the labeling process takes a time not less than a first threshold, said labeling unit executes the labeling process on a color-reduced image or low-resolution image of the received image.