Editing Signal processing (section)

{{Short description|Field of electrical engineering}}
{{Redirect-distinguish|Signal theory|Signalling theory|Signalling (economics)}}
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{{prose|date=June 2017}}
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[[File:Signal processing system.png|thumb|400px|Signal transmission using electronic signal processing. [[Transducer]]s convert signals from other physical [[waveform]]s to electric [[Electric current|current]] or [[voltage]] waveforms, which then are processed, transmitted as [[electromagnetic wave]]s, received and converted by another transducer to final form.]]
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 | footer            = The signal on the left looks like noise, but the signal processing technique known as [[spectral density estimation]] (right) shows that it contains five well-defined frequency components.
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'''Signal processing''' is an [[electrical engineering]] subfield that focuses on analyzing, modifying and synthesizing ''[[signal]]s'', such as [[audio signal processing|sound]], [[image processing|images]], [[Scalar potential|potential fields]], [[Seismic tomography|seismic signals]], [[Altimeter|altimetry processing]], and [[scientific measurements]].<ref>{{cite journal|last=Sengupta|first=Nandini|author2=Sahidullah, Md|author3=Saha, Goutam|date=August 2016|title=Lung sound classification using cepstral-based statistical features|journal=Computers in Biology and Medicine|volume=75|issue=1|pages=118–129|doi=10.1016/j.compbiomed.2016.05.013|pmid=27286184}}</ref> Signal processing techniques are used to optimize transmissions, [[Data storage|digital storage]] efficiency, correcting distorted signals, improve [[subjective video quality]], and to detect or pinpoint components of interest in a measured signal.<ref>{{cite book|title=Discrete-Time Signal Processing|author=Alan V. Oppenheim and Ronald W. Schafer|publisher=Prentice Hall|year=1989|isbn=0-13-216771-9|page=1}}</ref>