Star Valley Solutions
SVS-2000 MPEG2 Working notes
The
SVS-2000 is a hardware codec developed by the company Star Valley Solutions. It
is a rack
NWS is currently
using builds 2.7.2 and 2.9.6 beta++
Bugs
·
2.9.6
S-Video bug. This version has a bug where one must manually set the S-Video
input outside of the SVSDesktop GUI if one desires to use S-Video. First you
must force quit SVSDesktop and SVSEngine. Next open the app VidCap32 from the
Osprey-2000 folder in the Start menu. Select to show Preview, and find the
Video Source menu. Change the source from Composite to S-Video here. You should
see the preview. Relaunch SVSDesktop and now selecting S-Video will work.
·
I
do not recommend exceeding 256 kbps audio. The higher rates seem to be more
prone to nasty pops.
Tech specs
|
IP Protocol: |
UDP |
|
Port: |
20000
(default), or any of your choosing |
|
Datagram length: |
varies |
|
Datagrams/sec: |
varies |
|
Throughput: |
3-16 Mbps |
|
For MPEG audio/video specs please
see The
MPEG FAQ. MPEG2 is the most common digital video compression scheme—for
example, it is the format of DVD-Video |
|
Operating Recommendations
·
These
can be temperamental machines. You may find that after many enables and disables
of the stream that frame drops and other issues increase. NWS always recommends
that the machine is power cycled and is immediately run from this clean slate
state.
·
Both
locations do not need to, and it is discouraged, to start their streams at
precisely the same time. It is best to enable one machine first, and to enable
the second machine no sooner than 10 seconds later.
·
NWS
believes, through experience, that the CAMVision MPEG2 stream type is the most
robust, and should be used for both encode and decode. Avoid VBrick and
SVS-2000 MPEG2 streams between SVS units.
·
Audio
input into the machine should be monitored using the Osprey-2000 recording
device in the Windows Sound Mixer. You can find this in Control Panel, Sounds
and Audio Devices, Audio. While crude, the LED’s in the main mixer give you an
idea of signal level into the box. I do not recommend significantly altering
the input levels here, but this can also be done.
·
Haven’t
tried this in a while, but I believe sending to an invalid IP will cause the
machine to crash. Don’t do that.
Other Notables
·
The
SVS-2000 will not encode data if it is not receiving a video source.
·
When
it occurs, the only thing that will fix the common consistent 1 frame drop/sec problem
is power cycling the machine. This problem is often due to a loss of video sync
(genlock) on the analog input. Switching between non genlocked sources will cause this problem.
·
If
you suspect a problem receiving/decoding, check the incoming stream with VLC Media Player on any desktop.
Monitor Task Manager to verify incoming network traffic.
·
Visually,
the difference between 8 Mbps video and 15 Mbps video is barely perceptible. To
put this into perspective, the maximum total bit rate possible on a DVD-Video
is 9.8 Mbps. Most commercial DVD releases encode video at less than 6 Mbps.
Latency
·
SVS-2000
latency is directly related to the bit rate of the stream. Higher bit rate
streams (less compression) have less latency than lower bit rate streams (more
compression).
·
The
SVS-2000 audio bit rate setting has a greater affect on the latency than the
video bit rate. However, see bug above for why you should avoid audio bit rates
> 256 kbps.
·
At
8 Mbps video, 256 kbps audio, the latency of the SVS-2000 is still less than
DVTS.
·
I
would not mind more reliability at the expense of increased latency (<50 ms)
in these units. The audio artifacts of lost packets in these units is a serious
problem.