A two-stage filter for removing salt-and-pepper noise using noise detector based on characteristic difference parameter and adaptive directional mean filter

• Hongjin Ma,

  Roles Methodology, Software, Writing – original draft

  Affiliation School of Science, Northwestern Polytechnical University, Xi’an, 710129, China

  http://orcid.org/0000-0001-9052-3697

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• Yufeng Nie

  Roles Methodology, Writing – review & editing

  * E-mail: yfnie@nwpu.edu.cn

  Affiliation School of Science, Northwestern Polytechnical University, Xi’an, 710129, China

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