AVC Intra specs

[Phil Norris]

Hi.

I'm wondering what the official policy for AVC Intra 50 & 100 is for minimum system requirements for 1 stream 'native' AVC. There doesn't seem to be an official stat at the moment.

This would be useful for knowing if it's possible to edit AVC on a laptop. If so which would be recommended?

I've tried with a HP nx9440 dual core 2.6Ghz machine and 1 stream stutters a little.


Thanx.

[GrassValley_KH]

The understanding I have is that you will need something a little more meaty to get good, responsive, native editing of AVC-Intra. My experiences have only been on desktops, in which case the specs of our current line of workstations (based off HP xw8400) seem to handle a single native stream without too much effort.

(although, I believe my sample clips are 50Mbit...mileage may vary moving to 100Mbit)

I know that sounds rather vague, but the simple result is - you need more power than that offered by the laptop you tried it on.

[STORMDAVE]

Hi.

I'm wondering what the official policy for AVC Intra 50 & 100 is for minimum system requirements for 1 stream 'native' AVC. There doesn't seem to be an official stat at the moment.

This would be useful for knowing if it's possible to edit AVC on a laptop. If so which would be recommended?

I've tried with a HP nx9440 dual core 2.6Ghz machine and 1 stream stutters a little.


Thanx.

We might see Quad Core laptop CPU's next year, so you're in good shape :)

[Phil Norris]

It's definately a processor thing. The CPU performance was at 100% on both core for most of the time with 50 and 100, the buffer was only showing 1 or 2 from 128 in Edius for both formats. Regardless of the difference in bandwidth, it seemed the performance was about the same - very nearly realtime!?

I'm just trying to work out why that is? I expected to see the 422 1920 100mbit really choke compared to the 50mbit 1440 420 - but it wasn't so.

It seems maybe that because the 2 10bit formats are both converted to the same internal 8 bit codec for processing, then it might be that it is the internal codec at 1080 HD that is showing the same performance for both formats, and my laptop is just a little too small for the internal Canopus 8 bit codec - right?

But! if I can play DVCPRO HD (also converted to the int. codec for process?) with this laptop, then the 3 formats AVC50/100 and DVC PRO should surely all perform in the same way?

I suppose it's the conversion from 10 to 8bit with AVC that makes the difference, but I would like to know what the minimum sys requirements are for a stream of native AVC in Edius. Instead of just guessing like this.

[GrassValley_KH]

You're part of the way there on this track - there is indeed a 10-to-8 interpretation in there, but the very nature of AVC-Intra is that it is far more compressed than DVCPRO/DVCPRO HD. The system needs to decode the stream for playback - that is even before it can truly come out and have fun with effects, etc. Remember, the point of AVC-Intra is to deliever 10-bit full frame 4:2:2 video, without jamming up your P2 card in a matter of seconds! :)

The price, is that more computing power is needed to decode the stream, or, you use an intermediate codec (e.g. Canopus HQ, ProRes 422, etc.).

Btw, the EDIUS AVC-Intra plug-in has received some pretty awesome multi-threading optimisation in the various builds since the beta - which you've seen in the CPU utilisation.

[muleferg]

Thanks for keeping us posted on the AVC-Intra. Still waiting to upgrade my HPX2000
Mule Ferguson
Pumpkin Creek Video

[GrassValley_BH]

And to add to what Kenneally said, AVC-Intra doesn't get converted to Canopus HQ (or anything else for that matter) - it's a decode, then subsample to 8-bit. It remains uncompressed (just at 8-bit) until export.

[muleferg]

Thanks Brandon. So is it exported back as 10 bit?

Mule

[GrassValley_KH]

EDIUS doesn't do AVC-Intra export.

[Phil Norris]

I believe the 8bit uncompressed stream is used for export, so there's no 10bit workflow even if you have other 10 bit codecs installed.

I would love to be wrong about this :)

[STORMDAVE]

Yeah, Edius is only an 8bit editor.