Balancing settings

DaveGarratt

I suppose everyone tries to do this same balancing act but I am still a little sure what difference some settings have. I have read the document on performance settings etc. For the sake of argument I want to ensure I have the best quality image recorded to disk. I have 7 cameras running on a dedicated Mac Mini Quad Core i7 2.3ghz with 16gb Ram.

If I disk space/storage and network bandwidth is not an issue, but I don't want to burn out the fan's on the Mac Mini what sort of Video steam should I capture. For some reason H264 seems to provide smoother playback than jpeg. If I turn minimise video compression however it still seems to impact on CPU load quite a lot. I have followed your web page advice about text overlays, recompression and so forth. Should the H264 capture be better quality than the JPEG ?

I have 2 Y-CAM 1080p cameras, 4 x Axis M1004-W's and 1 USB.

I can email my settings if it would help identify any mistakes I've made.

Dave

DaveGarratt

After some experimentation I have come to the conclusion the best performance/quality balance for my setup is to move the responsibility for movement detection and recording back to the actual cameras themselves, and then use SecuritySpy to provide real time monitoring only using JPEG.

I have 6 cameras running and the average temp of the machine is around the low 60'c mark.

Dave

Ben

Hi Dave,

No codec is inherently "better quality" than another - it all depends on the quality setting and therefore the bit rate. With roughly comparable video quality, H.264 can produce a much lower bitrate (and therefore smaller files) than JPEG, as it's a much more sophisticated format. This sophistication comes at the cost of increased CPU usage required to decode (and especially encode) the video stream.

Generally, if your cameras are capable of sending H.264 video, then this is the best format to use with SecuritySpy. This does consume a bit more of the computer's CPU time to process compared to JPEG, but not very much more (since the computer is only decoding, and not encoding, the video). SecuritySpy can then save this H.264 video directly to disk, resulting in nice small file sizes.

Your Mac's CPU is designed to run at high temperatures - 60 is rather low and indicates that the processor is unburdened. The fan will of course increase the airflow to cool the processors if it needs to, but again this is what the fan is designed to do! The Mac will quite happily run for long periods of time with high CPU usage and high fan speeds if those are the conditions placed upon it. After all, if your Mac's CPUs are mostly idle, then you are basically wasting its powerful processing capabilities. It's like buying a really nice car but leaving it on the driveway and taking the bus instead, because you don't want to put miles on the clock.

DaveGarratt

OK -understood. One more question then. If SecuritySpy is not enabled for motion detection and nobody is viewing any of the camera's by whatever means - does this mean than the software is not pulling any video over the network ?

Dave

Ben

Hi Dave,

The video feeds will be continuously coming into SecuritySpy, even if the camera isn't being viewed or recorded at a particular point in time. This is because at any time the camera may be viewed, or switched to Active mode, or requested via the web server etc., and this allows SecuritySpy to instantly respond to this. If SecuritySpy had to reconnect to the camera in order to respond to any request for a video frame, there would be a several-second delay, which is not conducive to a good user experience.

We may review this in the future (e.g. have an option one way or the other), but for now that's the situation.

DaveGarratt

I for one would think that the ability to turn off the streaming until required would be a very good feature, especially for those camera's which have to be wifi as it consumes a lot of bandwidth