#!/bin/bash
s='![top command output linux](./img/wp-content-uploads-2022-04-top-command-output-linux.jpg)'
sed 's~!\[\([^][]*\)](\./img/\([^()]*\))~{{< image alt="\1" src="/images/post/\2" >}}~g' <<< "$s"
sed -E 's~!\[([^][]*)]\(\./img/([^()]*)\)~{{< image alt="\1" src="/images/post/\2" >}}~g' <<< "$s"
# {{< image alt="top command output linux" src="/images/post/wp-content-uploads-2022-04-top-command-output-linux.jpg" >}}