Signal-to-noise ratio (imaging)

<h2 id="definition-of-snr">Definition of SNR</h2>
<p>Traditionally, SNR is defined to be the ratio of the average signal value 
  
    
      
        
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    {\displaystyle \mu _{\mathrm {sig} }}
  
 to the <a href="/facts/Standard_deviation/qSug9BRl">standard deviation</a>  of the signal 
  
    
      
        
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    {\displaystyle \sigma _{\mathrm {sig} }}
  
:<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a><a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a>
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    {\displaystyle \mathrm {SNR} ={\frac {\mu _{\mathrm {sig} }}{\sigma _{\mathrm {sig} }}}}

<p>when the signal is an optical intensity, or as the square of this value if the signal and noise are viewed as amplitudes (field quantities).
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Coefficient_of_variation/V8ddKkz4">Coefficient of variation</a></li>
<li><a href="/facts/Contrast-to-noise_ratio/N7a5sajw">Contrast-to-noise ratio</a></li>
<li><a href="/facts/Minimum_resolvable_contrast/Wvs8hM2k">Minimum resolvable contrast</a></li>
<li><a href="/facts/Minimum_resolvable_temperature_difference/T0BF08kQ">Minimum resolvable temperature difference</a></li>
<li><a href="/facts/Optical_transfer_function/k9hR8A7o">Optical transfer function</a></li>
<li><a href="/facts/Signal-to-noise_ratio/qohClhyG">Signal-to-noise ratio</a></li>
<li><a href="/facts/Signal_transfer_function/3yckq096">Signal transfer function</a></li></ul>

<h2 id="further-reading">Further reading</h2>
<ul><li><a href="https://www.iso.org/standard/28835.html">ISO 15739:2003, Photography – Electronic still-picture imaging – Noise measurements</a>: specifies methods for measuring and reporting the noise versus signal level and dynamic range of electronic still-picture cameras. It applies to both monochrome and colour electronic still-picture cameras.</li>
<li><a href="https://www.iso.org/standard/37777.html">ISO 12232:2006, Photography – Digital still cameras – Determination of exposure index, ISO speed ratings, standard output sensitivity, and recommended exposure index</a>: specifies the method for assigning and reporting ISO speed ratings, ISO speed latitude ratings, standard output sensitivity values, and recommended exposure index values for digital still cameras. ISO 12232:2006 is applicable to both monochrome and colour digital still cameras. It revises ISO 12232:1998.</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>ISO 12232: 1998 Photography – Electronic Still Picture Cameras – Determining ISO Speed <a href="https://www.iso.org/standard/21020.html" target="_blank">https://www.iso.org/standard/21020.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Janesick, James R. (2007). 9780819478382/10.1117/3.725073 Photon Transfer. doi:10.1117/3.725073. ISBN 978-0-8194-7838-2. {{cite book}}: Check |url= value (help) <a href="978-0-8194-7838-2" target="_blank">978-0-8194-7838-2</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Rowlands, Andy (April 2017). Physics of Digital Photography. IOP Publishing. ISBN 978-0-7503-1243-1. <a href="978-0-7503-1243-1" target="_blank">978-0-7503-1243-1</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
</ol>

Signal-to-noise ratio (imaging) open-in-new

Signal-to-noise ratio (imaging)