Does any one know how to install ffmpeg for php on server
On window or Linux server? I want to use ffmpeg for merging the sound on server.

JavaScript query:- I have number of sound clip on server. Which user can create different mixer sound by combination or by merge. How can I save the output merge sound by JavaScript or php in user local desktops or mobile.

How to encrypt JavaScript code for securely sending score to server. Any ideas?

I want to do one project in which using arduino uno and RFID reader to take attendance but for this I have to need 100 reader card which is costly. So I thought using bar code so I can print barcode on paper and no need any card. So does anyone idea where I can get bar code module for arduino uno.