Adly T. Fam, Yong Hoon Lee, Sung Jea Ko

Research output: Contribution to journalConference articlepeer-review


Median filtering can be viewed as an operation that selects a sample from each window close to the last output. This observation results in an edge-preserving smoother called the last output reference (LOR) filter. The LOR filter is similar in function to the median or recursive median filters, but has additional advantages particularly in suppressing impulses. It has been shown that repeated applications of LOR filtering produces a sequence that is invariant to subsequent passes through the same filter. Also, it has been proven that any sequence can be converted to a locally monotone sequence by using a combination of forward and backward LOR filters. When the LOR filter is applied to an actual noisy image, it is shown to perform well.

Original languageEnglish
Pages (from-to)1248-1251
Number of pages4
JournalICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings
Publication statusPublished - 1987
Externally publishedYes

ASJC Scopus subject areas

  • Software
  • Signal Processing
  • Electrical and Electronic Engineering


Dive into the research topics of 'ORDER STATISTIC LAST OUTPUT REFERENCE FILTERS.'. Together they form a unique fingerprint.

Cite this