1. A method comprising: identifying sets of connected components in a video frame of a video sequence; displaying alternate trajectories of selected connected components through a user interface; removing at least one alternate trajectory of the selected connected components responsive to a user interface input, wherein the user specifically classifies the at least one alternate trajectory as a wrong candidate and the at least one alternate trajectory is removed; generating a confidence level for the alternate trajectories belonging to the selected connected components, wherein the at least one alternate trajectory classified as a wrong candidate by the user is excluded from being one of the alternate trajectories belonging to the selected connected components for which the generated confidence level is generated; eliminating alternate trajectories having a confidence level below a predetermined value and the at least one alternate trajectory classified as a wrong candidate by the user to remove; and displaying images of said video sequence responsive to the removing, generating, and eliminating.