Re: [Avid-L2] DNx145 or XDCAM HD 50Mbit - which is easier to cut with ?

XDCAM HD is long GOP compression. Long GOP means for some frames in the
sequence, data is needed from frames before and after to correctly display.
This causes lag.

DNxHD is I-frame compression. Each frame is compressed indiviually and can
be represented independently.

Long GOP compression is extremely efficient. For that 50 Mbps, you're
getting the equivalent of 150 Mbps bandwidth (my rough estimation). But for
it to be realized it must be played in sequence. So the gain doesn't exist
if you're editing with it. The only gain there is smaller storage
requirements.

I-frame compression is not as efficient, but is much easier on the
processors. It requires more space, but you gain performance.

In any case, it's worth trying each, but you'll go with the one that gives
better performance in an editing environment, and that will generally be an
I-frame codec like DNxHD.

On Tue, Mar 27, 2012 at 10:18 AM, David <k27usa@yahoo.com> wrote:

> **
>
>
> OK - we've been doing some remote editing using standard MacBookPro 2.53
> Intel Core Duo w/4BG ram. We have anywhere from 3 to 7 44min eps to pull
> bites & b-roll from to cover intvw footage. One of our engineers suggested
> we ingest using the XDCAM HD 50Mbit (1080i/60) codec in order to save drive
> space. What I'm finding is that the system bogs down & really struggles -
> spinning beach ball, etc - when trying to access that footage using AMA (I
> know Avid does not recommend using AMA to edit with) so I ended up
> re-importing (instead of transcoding) the episodes at DNx145 and while that
> took considerable time it turned out that the DNx145 is much easier to edit
> with. Far less spinning beach balls.
> Is the XDCAM codec more processor intensive because of the compression ?
>
> Also - I know more RAM is always good, but does anyone think it would make
> a really noticeable difference ?
>
> Thnx in advance
>
> Dave B
>
>
>

[Non-text portions of this message have been removed]

------------------------------------

Search the official Complete Avid-L archives at: http://archives.bengrosser.com/avid/
Yahoo! Groups Links

<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/Avid-L2/

<*> Your email settings:
Individual Email | Traditional

<*> To change settings online go to:
http://groups.yahoo.com/group/Avid-L2/join
(Yahoo! ID required)

<*> To change settings via email:
Avid-L2-digest@yahoogroups.com
Avid-L2-fullfeatured@yahoogroups.com

<*> To unsubscribe from this group, send an email to:
Avid-L2-unsubscribe@yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/