1. An image recognition apparatus, comprising: a storage unit configured to store a dictionary used to recognize a predetermined pattern; a recognition unit configured to detect in image data using the dictionary, as predetermined patterns, a plurality of partial regions having a likelihood of being the predetermined pattern greater than a predetermined threshold; a display unit configured to display the image data, and also display information indicating the plurality of partial regions detected as the predetermined patterns; an accepting unit configured to accept a positive region specified by a user from among the detected predetermined patterns; a determination unit configured to determine the detected predetermined patterns other than the specified positive region as a negative region; a generation unit configured to generate a negative learning sample image based on the determined negative region; and an update unit configured to update the dictionary based on the negative learning sample image.