1. A method of categorising defects in a media item, the method comprising the steps of: receiving a binarised image of the media item, where the binarised image comprises a plurality of pixels, each pixel having either a potential defect intensity or a non-defect intensity; identifying one or more blobs comprising contiguous pixels each having a potential defect intensity; for each identified blob, comparing a size of the blob with a damage threshold; ignoring the blob if the blob size is smaller than the damage threshold; and for each identified blob having a size exceeding or equalling the damage threshold, categorising the identified blob.