Advanced Simulation Technology inc.
Record & Replay FAQs

What is the Relationship between Disk Size and Record Times?

When using Mu-law compression (DIS standard), a voice stream is represented by 8000 samples per second, and 8 bit words per second. This is 8K bytes/second, and equals 28,800 kbytes (approx. 29 meg) per hour, for each independent audio stream.
This translates to approximately 35 hours of recording per gigabyte of free disk space.
Disk space can be conserved by mixing audio streams. For example, recording ten independent audio streams for an hour will consume about 290 megabytes; if you mixed them all down to a single audio stream, it would use only 29 megs. Once mixed, however, the previously-independent audio streams cannot be separated.
Remember, the silence portion of speech is also recorded; otherwise synchronization becomes a major issue.