NCast Presentation Recorder Reference Manual
6. Archives
6.1. A
RCHIVE
S
ETTINGS
The Presentation Recorder units allow complete recording of audio and graphics streams onto internal
storage for later retrieval and playback.
The estimate for recording time is a simple calculation based on the bit-rate set for the channel.
Take the bit rate set for the channel in use and divide by eight to get the bytes/second of archive space
needed. Multiply by 3600 to get the bytes required per hour.
So for a 5 Mbps stream (graphics plus audio) we estimate 625,000 bytes/second or 2.25 GB per hour. If we
use a 16 GB archive disk that's about 7.1 hours of recording. The disk size in the unit is noted at the
beginning Archive page.
The resolution and frame-rate of a channel aren't as important as the max bit-rate set for operation.
Recording times may be slightly longer than the above calculation would suggest because the actual bit-rate
generated during operation varies with the material being encoded, and the calculation above should
represent worst-case conditions.
Archive files are named with time-stamp information indicating the start time of the archive:
yyyymmdd-hhmmss-nnn.mp4
where
yyyy Year of archive
mm
Month of archive
dd
Day of archive
hh
Hour of archive
mm
Minute of archive
ss
Second of archive
nnn
Channel number
.mp4 File format, MPEG-4
The default archive filename may be changed (See Section 5.10.2 above).
NCast Corporation
Revision 2.2
Page 53
