Marker detection in X-ray images

A method for detecting markers within X-ray images, comprising:

• receiving an image sequence comprising a plurality of X-ray image frames;
• applying one or more directional filters to the image sequence;
• identifying a plurality of marker candidates based on the results of the directional filters;
• computing distance between all possible pairs of marker candidates;
• determining an average distance from the computed distances;
• detecting a first marker at a location of a marker candidate of the plurality of marker candidates that occurs at substantially the same location within the greatest number of X-ray image frames of the image sequence;
• and
• detecting a second marker at a location of a marker candidate of the plurality of marker candidates that is spaced from the first marker location by substantially the average distance.

A computer system comprising:

• a processor;
• and
• a non-transitory, tangible, program storage medium, readable by the computer system, embodying a program of instructions executable by the processor to perform method steps for detecting markers within X-ray images, the method comprising:
• receiving an image sequence comprising a plurality of X-ray image frames;
• applying one or more directional filters to the image sequence;
• identifying a plurality of marker candidates based on the results of the directional filters;
• computing distance between all possible pairs of marker candidates;
• determining an average distance from the computed distances;
• detecting a first marker at a location of a marker candidate of the plurality of marker candidates that occurs at substantially the same location within the greatest number of X-ray image frames of the image sequence;
• and
• detecting a second marker at a location of a marker candidate of the plurality of marker candidates that is spaced from the first marker location by substantially the average distance.