Zipstream May Not Be So Zippy On Playback...

Came across this Axis deck on zipstream that contained this panel:

maybe just axis being conservative...

Has anyone tried high-speed scrubbing back and forth on an aggressively GOP compressed zipstream?

4x may seem fast enough, but as I found out after purchasing an NVR that maxed out at 4x, it can be supremely irritating if you have a lot of ground to cover. Ditto with latent scrubbing back and forth.

Not mentioned but worth investigating is possible issues with multi-window jumbo GOP playback.

Anybody seen anything one way or another?


Ethan, test this. Let us know.

Very similar to when h264 came out, freezer and rewarding was I frame only.

Need to buffer the video and/or decode p frames...

...freezer and rewarding was I frame only

assuming you mean fast-freezer? :)

Doh! Yeah, auto correct kicked in and I didn't notice it. Thanks.

That should have been "fast-forwarding and rewinding was I-Frame only".

I know one manufacturer added a "smooth playback" option which buffered the video to allow FF/Rew playback that included P-frames, but it was a hidden menu that most end users or SI would never know about...

I have no issues playing a Zipstream camera back at even 64x in Exacq. I'll grab some samples and drop them here.

Granted, Exacq buffers things prior to playback, but so do most, I believe.

Cool!

When you say samples do you mean the raw zipstream video file, or a video of the playback?

It would be great to get a raw h.264 file with GOP stretching intact for those of us who are ARPTECally challenged, though I'm not sure that possible.

Ethan,

What about reverse playback? UD2M mentions freeze frame and rewinding (I'm fluent in spellcheckese) - from my experience, the 'I-frame only' limitations are in reverse playback - not in forward (any speed) playback.

Am I wrong?

Is that maybe just a disclaimer for their Companion software rather then most VMS'?