Avid MC File Size Limits and nano 3.7GB files
 

I've not encountered this issue in searching any of the forums: A client is having problems importing .MXF files recorded from a hard-mounted Iconix camera to my nanoFlash into Avid Media Composer and they suspect that the default 3.7GB max file size of the nanoFlash recorder may be to blame. The smaller files play ok but they're having problems with the large ones. Knowing they are editing on Avid MC I set the unit to I-Frame/MXF 180mbps but I've seen no advisory to reduce max file size. To be honest, I'm on the verge of simply not offering the nanoFlash as an option for anyone I know to be editing in Avid because responding to all of these e-mails after the fact is taking up too much of my time.

Stephen McCarthy

Just to test this, I imported a 7.5GB file from my film short. Brought it in DNxHD 75 (1280x720). It's not the file size that's causing you an issue.

Avid Media Composer 5.0 and 180Mb
 

Hello Stephen,

This is Andy with Convergent Design, I recently tried to replicate your issue, but found that Avid seems to import 180MB I-frame, and Long Gop Files just fine, Also we are using Avid 5.0, are you using Avid 3.5? as well as what software version for the nanoFlash are you using? this test was with 1.6.29 our latest release, Also it is possible that your video format might make a difference, my test was with a sony ex3, 1080i 60 180Mb Iframe MXF. If you would like to contact me directly feel free, @ andy@convergent-design.com, hopefully we can figure out what is happening.

Andy Mangrum
Tech Support
Convergent Design Inc.

Hi Andy,

I must agree with you here.

MC 4.05 no problems.

MC 5.00 no problems. Great improvement overall.

Stephen,

Definitley a sub zero issue.! ie,( Look for a fault in the other direction.)

Mike.

Stephen,

Just as a after thought.

In MC 4.05.

There were times when Transcoding more than two or three NanoFlash MXF files

at a time to DNX 185 that MC4.05 would complain.

But all MXF file no matter what the size transcoded individualy were fine.

In MC5 one can Transcode many files. No problems.

Hope this might help.

Mike.

Off topic, but...
 

Welcome aboard Andy! In case you're new to CD as well as the forum, I thought I'd mention what a great bunch of people you now work with, and hope you enjoy your new job. (If you're an old hand there, then you know this already).

Though we're a pretty eclectic group, everyone tries to help everyone, there are no trolls here, and we all love our nano's and XDR's. I'm no one special, and I shouldn't speak for anyone else, but I feel pretty confident that the previous sentence is fairly accurate.

Billy

Response from edit room:
 

Here's the feedback I got from the edit room. Don't know if it qualifies as a "final" resolution or if it suggests a different kink in the work flow.
--------------------------------------------------------------
From the edit room:

Hey Stephen,

So we converted the files and are good to go. However, this was quite a lengthy process - so to make it a bit easier for future shoots below is some info regarding our workflow that could be helpful. First, we found this posting from a forum (http://www.dvinfo.net/forum/converge...ml#post1437054). It seems as thought the nanoFlash MXF codec is still under testing and will be upgraded. Here is what we tried and ended up doing:

* can avid see the mxf files as native media? no
* can avid import the files? crash
* can avid link to them by AMA? Yes, but then try to do anything with
them, crash
* FCP direct import? no
* FCP log and transfer? no
* Compressor import? No
* VLC export to quicktime? No
* Calibrated Software's MXF reader? No, can't install if you have FCP
* Sony's XDCAM reader? No
* mxf4mac? too expensive ($400)
* Aunsoft? Yes! ($35 software, has a lot of settings, but after fiddling we found a usable one to make h.264 QTs).

All in all we got a result that is fine, but until nanoFlash updates the MXF Codec to jive with FCP and Avid, it seems that Quicktime is the most versatile format.

------------------------------------
From the producer cross posting to another group:

--- In Avid-L2@yahoogroups.com, "Daniel McCabe" <dmccabe@...> wrote:

Dear Avid Mavens,

I am working on a project that includes some mxf files created on a
nanoflash device recording a lipstick camera. The recording format was
720p at 59.94fps. The files aren't working in MC 4.

I am on the road and not able to see the errors myself but I am told the
Avid says there are corrupt frames. VLC player reads back the files
fine. In the field, the nanoflash played back the files without a
problem.

I'm hearing several theories as to why there are issues, one is based on
the file size. Some of the files are over 2 gigs. Are there still issues
with Avid dealing with files over 2 gigs in size? (I've only bumped into
that exporting OMF for a protools session.)

If that limit exists, anyone got a suggestion how to break the files
into smaller ones if we can't get them into Avid?

Sorry for the rather vague symptoms. Thanks for any assistance.

D.


----- Original message -----
From: "Andres" <aalegria@hoff.tv>
To: Avid-L2@yahoogroups.com
Date: Thu, 01 Jul 2010 22:07:51 -0000
Subject: [Avid-L2] Re: MXF files from nanoflash device

We've just been working with mxf files recorded on a Nanoflash. We had
some problems that were related to the bit-rate the files were recorded
at on the Nanoflash. We have plenty of files that exceed 2GB and they
import and play fine in Avid. This should help: it's from Greg's post in
another thread:


Avid uses our files just fine, if you follow the following rules.

1. Use MXF not MOV (Quicktime).

2. Use Long-GOP if recording 18/35/50 Mbps.

3. Use I-Frame Only if recording above 50 Mbps.

All bit-rates work, when using I-Frame Only.
We try to tell everyone these rules and it is probably in our manual.

We have been waiting for a long time for Avid to increase the size
of their internal buffer.
The problem is that their buffer is too small to hold a whole Long-
GOP, if the bit-rate is above 50 Mbps.

When the editing or playback stops, Avid looks in the internal
buffer for the start of the GOP. If using above 50 Mbps, they can't
find the first frame of the GOP, resulting in the
"decompStream:FillBuffer FIFO too small for read )," error.


So, when using nanoflash XDCam codec, stick with 50Mbps for now, or
use all i-frame, until Avid and the Nanoflash guys get this sorted
out. I was able to use .mov via ama with identical results to
the .mxf, for what it's worth, but in the end, transcoding to DNx was
the only way to make the footage useable. Except, of course, the
nanoflash is often used in conjunction with the on-board HDCam
recorder - consequently there's a backup tape! This is a great hybrid
workflow for people who want a tape element AND file-based workflow.

gh

Hi,

What is all this mumbo jumbo.

Are they working on a qualified Avid system plus respectable hard drive arrays.

If they were they would not have any problems importing the NanoFlash

MXF files.

Sorry to be blunt.

Cheers.

Ps. What codec is being tested? There is a difference between firmware and the codec. The firmware changes have never stopped MXF I frame files being imported into Avid.

The Long-GOP / I-Frame issue has been LONG understood in Avid. I didn't pay a lot of attention to it because I had neither Avid nor a Nanoflash, but I do remember reading about it. Now that I have Avid, I'll be following more closely. Honestly, I thought this was resolved, but I guess not.

I've read a post on the Avid fourm that MC5 does not have the 50 mbps Long-GOP limitation.

The new Media Composer has native support for several formats...more than several actually.

I'd be surprised if it couldn't handle Long GOP...Long GOP is the bulk of the acquisition field in the middle of the bell curve of our industry...XDcam (HD, EX, HD422), DSLR, and even AVCHD produces far better pictures than it has a right to IMO.

...also, the initial problem reported was with 180 Mbit I-frame, not Long GOP.

I think it's the M-any X-cruciatingly variable F-actors wrapper myself.

At one time, many of us thought that MXF was going to save us all from geriatric QuickTime and the not-officially-supported-since-Carter-was-in-office AVI file format... but they made the standard so wide that it doesn't seem to be much of a standard.

Tim, of course Avid Media Composer can handle Long-GOP. It's Long-GOP that's greater than 50mbps that causes MC4 and prior to barf. Apparently this is no longer the case in MC5.

If in Doubt with Avid MC, then use these settings
 

Hi All:
Yeah, I use Avid Media Composer almost exclusively (ver 4.0.5.x) and the sweet spot hassel free settings I use which always work are......

Long GOP MXF 50 Mbps. Use this and there will be no post headaches for the producer. I shoot wierd combinations of fps too and no problems with my Flash XDR and Avid post.

i.e. Canon 24 F (23.98 fps)

Canon 1080i 59.94 fps

I'm using XDR firmware ver 1.5.55 (Nano uses more or less the same thing with a different number)