I needed to email an HTML report and I was not happy with the fact that we have to create zip file containing the HTML, Images etc. I knew it was possible to embed base64 data directly into HTML I started looking for some PoC. My search took me to an online base64 encoder and decoder. This gave me the idea to convert the external image files into base64 string and embed it directly into HTML. On some search I landed up Apache Commons Codec Library which contains a Base64 class which can be used to covert an input stream into a base64 string.