Video Anayltics and compressed video.

[johrt]

Can video analtics be performed on compressed video. What I have read seems to indicate that it can not. What would be some of the ptifalls if analytics were able to be performed on compressed data. If compressed data is OK, what format is preferred?

[Steve]

Are you talking about prerecorded video?

[johrt]

Could be. But what I am concerned with is normal digital video using jpeg4 or other simlar compression. The thought is that I would perform any required analytics from a centralized location.

[Steve]

Well I guess it would depend on where you are recording the video from. An IP Camera or Video Server would be taking the video and compressing it before the video analytics kick in. So my answer would be yes, video analytics can be performed on compress video.

I'm not 100% certain though as I don't fully understand the question.

What would you be recording the video from? IP Camera, CCTV Camera or Video Server?

[chad_cooper]

To my knowledge, video analytics must be perform prior to compression or the video must be decompressed, then the analytics can run, then recompressed and saved. Different manufacturers do some very neat tricks to help save CPU load during this time.

If this is at the camera, it is much easier to do the analytics prior to compression.

I think you where talking about MPEG4 compression.

Hope it helps

[fwboyd]

Depends on what you mean compressed.

All digital video has some loss when converted from analog, so the particular codec is key - along with resolution.

We have been writing video analytics for our traffic market using H.264 video, which is "compressed" about 3X over MPEG2 for example.

Our experience suggests that camera quality (TVL count), resolution (we use full D1) , and lens selection (wide angle warps objects) can affect success rate, but H.264 is not a contributor.