When you say that the audio should be compressed before sending, does the quality of the compressed audio matter? For example, are you willing to accept a lower quality lossy-compression stream from the lossless file?

I am not sure. I believe if you use Wireshark and TShark you can, however I do not believe it is OSS.

Off the top of my head, you could use TCPDump which is an open source packet capture software, and Splunk which can be used for the statistics parts (However, not all versions are free, and it is not open source). However, I am refraining from answering the question as I am unsure if this setup with two programs would be ideal.

Should this work with any chat site, or is this going to be for a specific site? Does the chat use an IRC backend?

Have you tried VLC?

What version of Windows are you Running?

What you could do is set up a Virtual Machine (or two) and have the Guest (or one VM) be used by someone, and the Host (or the other VM) be used by someone else. Check This out if you are curious to learn more.

Have a look at gImageReader. It is based off of Tesseract OCR. The former is licensed under GPL v3 while the latter is licensed under Apache 2.0.