I am a new Android user, and recently I have upgraded the default ROM of Samsung Galaxy S 3 to Jelly Bean MIUI ROM using the steps mentioned at the International Business Times.
Now I want to revert it back to default ROM but I am unable to do so.
Although the blog says
If you want to return to your previous ROM for some reason, boot into recovery (using the procedure explained in step 3), choose backup and restore, then restore your previous ROM by selecting it from the list.
But I didn't find anything within the list.
I tried wipe data / factory reset but still not getting the default ROM.
What do I need to do to get back the default firmware?