Onscreen audio recorder extension for chrome

I need extension for Chrome browser which will allow user to record onscreen audio which is playing on browser. Also user must be able to create timestamps where he will be able to mark time with note and system will make marks for fast search of these timestamps. Saving audio will be to mp3, description of audio and all notes will be stored in mysqli. It must work on any site where user can view video or audio (youtube, twitter, facebook, cnn, bbc etc)