I3E Technologies, #23/A, 2nd Floor SKS Complex, Opp. Bus Stand, Karur-639 001. IEEE PROJECTS AVAILABLE, NON-IEEE PROJECTS AVAILABLE, APPLICATION BASED PROJECTS AVAILABLE, MINI-PROJECTS AVAILABLE. Mobile : 99436 99916, 99436 99926, 99436 99936 Mail ID: i3eprojectskarur@gmail.com

1. LOCAL DIAGONAL EXTREMA PATTERN: A NEW AND EFFICIENT FEATURE
DESCRIPTOR FOR CT IMAGE RETRIEVAL
ABSTRACT
The medical image retrieval plays an important rolein medical diagnosis where a
physician can retrieve most similarimages from template images against a query image of a
particularpatient. In this letter, a new and efficient image features descriptorbased on the local
diagonal extrema pattern (LDEP) is proposedfor CT image retrieval. The proposed approach
finds the valuesand indexes of the local diagonal extremas to exploit the relationshipamong the
diagonal neighbors of any center pixel of the imageusing first-order local diagonal derivatives.
The intensity values ofthe local diagonal extremas are compared with the intensity valueof the
center pixel to utilize the relationship of central pixel with itsneighbors. Finally, the descriptor is
formed on the basis of the indexesand comparison of center pixel and local diagonal extremas.
The consideration of only diagonal neighbors greatly reduces thedimension of the feature vector
which speeds up the image retrievaltask and solves the “Curse of dimensionality” problem also.
TheLDEP is tested for CT image retrieval over Emphysema-CT andNEMA-CT databases and
compared with the existing approaches.The superiority in terms of performance and efficiency in
terms ofspeedup of the proposed method are confirmed by the experiments.