I developped a SW for restaurants, pub, ecc...
It's developped in php (and html, javascript, mysql) and runs by an Apache webserver (phpdev 4.2.3). The my system is not absolutely connected to the web.

It is a client-server system: in the server is installed Apache, while the clients are PCs where only a web browser (IE) is running, connected to the server via Wi-Fi.

I have the following problem:
I want to show in the clients some videos (huge files); therefore I would kike to avoid to download them everytime from the server (in order to not overload the Wi-fi network).
The client should call a php page from the server, but the video file should be downloaded from the own (client) HD.

The question is:
Is it possible to open a file (in my case a video file) on the Local HD of the client PC by a javascript?
Please consider that, if it could be a restriction problem on the client PC, I can change the configuration because it is not an internet application.

I'm not very expert, I'll really apprieciate if you can add some code rows to help me...

Thank you very much in advance and ciao from Rome