Method and system for verifying geographical descriptiveness of media file

摘要

The invention relates to a system for verifying geographical descriptiveness of a media file, such as a picture. The system comprises storage means adapted to store a media file, communication means adapted to send said media file to a plurality of user terminals, and to receive, from the user terminals, data indicating a guessed geographical position with which the user of each user terminal associates the media file. The system also comprises calculation means adapted to determine whether the media file is indicative of a geographical position based on the guessed geographical positions received from the plurality of user terminal.

主权项

1. A method for verifying geographical descriptiveness of a media file, the method comprising:
storing, in a first storage medium, a media file and data indicating an assigned geographical position for the media file; sending said media file to a plurality of user terminals; receiving, from each of the plurality of user terminals, data indicating a guessed geographical position with which the user of that user terminal associates said media file; updating the assigned geographical position for the media file based on the guessed geographical positions received from each of the plurality of user terminals; and determining whether said media file is indicative of a geographical position by:
either comparing the assigned geographical position with each guessed geographical position, or comparing the guessed geographical positions with one another; andcalculating a verification rating for the media file based on said comparison, the determination as to whether or not the media file is indicative of a geographical position being based on said verification rating, wherein the verification rating value is recalculated each time data indicating a guessed geographical position is received, the verification rating being recalculated as follows:if⁢⁢Pa-pi>dmax⇒χVR⁡(updated)=χVR,elseχVR⁡(updated)=χVR+(1-(Pa-pidmax)), where Pa is the assigned geographical position of the media file, pi is the latest received guessed geographical position, |Pa−pi| is the geographical (Euclidean) distance between the assigned geographical position and the latest received guessed geographical position, dmax is a threshold value for the maximum distance allowed between the assigned geographical position and the latest received guessed geographical position in order for the guess to be classified as correct, χVR (updated) is the new verification rating of the media file, and χVR the verification rating of the media file prior to the reception of the latest received guessed geographical position.