1. A barcode image recognition system applied in a hand-held device comprising: an image processing module, for receiving an image and determining a barcode region according to a characteristic of the image; and a barcode recognition module, coupled with the image processing module, for recognizing the barcode region and outputting a plurality of characters associated with the image, wherein the barcode recognition module comprises: a character region segmentation module, for segmenting at a recognition position along a second direction of the barcode region, and calculating a number of alternations between black and white pixels in the barcode region along a first direction at the recognition position to provide a plurality of corresponding character regions, a feature vector extraction module, for providing a corresponding feature vector for each of the character regions according to the widths of the black pixels and the white pixels in each of the character regions, and a matching module, for matching the corresponding feature vector of each of the character regions with a plurality of matching vectors, each of the matching vectors corresponds to a character; wherein when the feature vector matches with one of the matching vectors, the matching module matches the character region with the character that corresponds to the one of the matching vectors, and wherein the hand-held device comprises an input interface for receiving a user input character, the barcode recognition module still further comprises: a learning database, operating in a learning mode and a recognition mode; while operating in the learning mode, the learning database records and correlates the feature vector with the user input character; while operating in the recognition mode, the learning database provides a corresponding matching vector for the feature vector which the learning database records.