I am using 2 Canopy 400 series 4.9GHz AP’s and 6 SM’s to steam 6 video streams back to one location. There are 3 cameras on 1 AP and 3 cameras on the other AP. My question is about the uplink/downlink % … with the cameras being on the SM’s do I need to have the uplink or downlink on the AP’s set higher?
The reason I ask this is that I would like to maximize the bandwidth to each camera so that we can have higher quality video. The cameras are fixed so not much bandwidth needed to the camera just from.
Also has anyone had issues when streaming video over the canopy400 when using the h264 compression? Any info would be appreciated. Thanks in advance.
When deploying camera systems you will want to change the bandwidth allocations so that you get more upstream from the SM than downstream. This is contrary to how you would set up a WISP network, but it makes complete sense. I think a happy medium would be 10% downstream 90% upstream. This would permit you to push high bandwidth streams while still permitting PTZ control should you so have it.
Remember: Depending on the system design (what you are trying to accomplish) you may need 30FPS and 4CIF resolution. This means that you are going to push near 10Mbps (using MJPEG) of traffic through each SM link to the NDVR. H.264 drops this to about 2Mbps. MJPEG is much better image quality, as the compression is less, and depending on the level of MJPEG compression you use, this could easily come close to 20Mbps per camera of IP stream. This results in a better capture. I like MJPEG and use it whenever possible as it stands better chances of being admissable evidence in court.
If you are recording 24x7 using MJPEG, this means that you will have that amount of traffic all the time. Motion Detection or alarm input driven recording can reduce network saturation if so desired. Also, some systems permit VBR recording, so no event triggers means you scale down throughput by reducing FPS, and upon event, ramp up the FPS which drives the throughput higher this resulting in high-quality captures.
Speaking of FPS here is a little Youtube video I have found that demonstrates the various FPS settings and how they affect the stream.
http://www.youtube.com/watch?v=JpiVbnYCJX4
You should try and shoot for 7-10fps as this is a decent rate that won’t chew up too much bandwidth. I have customers that want 30fps but when I show them this video they see there is very little difference between 15 and 30, so I set them to 15, which effectively doubles their storage time, and halves their network load.
Very good video! Was nice to see a comparison.