Windows – Howto Hide Files inside JPGs – tweak hack xp vista
Learn to hide any file(s) inside a regular jpg image. Simple quick trick.
Free Compression software I used
This works by copying the compressed file in binary mode onto the end of the jpeg images. When the picture is opened, the jpg header says the length of the data and ignores everything below (the hidden zip file). When the compression software like 7-zip opens the picture it looks for compatible compression headers and starts reading the file where-ever those begin.