This image shows some kind of formula that could be converted to TeX. Storing formulas as images makes it harder to change them. TeX also helps making sure that they all use the same font and size.
A replacement has been proposed:

${\displaystyle {\xrightarrow[{\text{Message}}]{W}}{\begin{array}{|c| }\hline {\text{Encoder}}\\f_{n}\\\hline \end{array}}{\xrightarrow[{\mathrm {Encoded \atop sequence} }]{X^{n}}}{\begin{array}{|c| }\hline {\text{Channel}}\\p(y|x)\\\hline \end{array}}{\xrightarrow[{\mathrm {Received \atop sequence} }]{Y^{n}}}{\begin{array}{|c| }\hline {\text{Decoder}}\\g_{n}\\\hline \end{array}}{\xrightarrow[{\mathrm {Estimated \atop message} }]{\hat {W}}}}$

In your article, replace the image with:

<math>\xrightarrow[\text{Message}]{W}
\begin{array}{ |c| }\hline \text{Encoder} \\ f_n \\ \hline\end{array}
\xrightarrow[\mathrm{Encoded \atop sequence}]{X^n}
\begin{array}{ |c| }\hline \text{Channel} \\ p(y|x) \\ \hline\end{array}
\xrightarrow[\mathrm{Received \atop sequence}]{Y^n}
\begin{array}{ |c| }\hline \text{Decoder} \\ g_n \\ \hline\end{array}
\xrightarrow[\mathrm{Estimated \atop message}]{\hat W}</math>

This SVG image was uploaded in a graphics format such as GIF, PNG, JPEG, or SVG. However, it consists purely or largely of information which is better suited to representation in wikitext (possibly using MediaWiki's special syntax for tables, math, or music). This will make the information easier to edit, as well as make it accessible to users of screen readers and text-based browsers.