FFAStrans forum

Hi all

I have tested to AMA link the proxy XDCam file but I'am not be able to play it on AVID.
I have open a ticket with AVID for that
I will give you some news very soon

Hello friends!
Is there any news on this subject?

To come back to this old topic, I have created some files with a AVID Mediacomposer.
I uploaded them to the FFAStrans.com/Share in the samples folder.
They are named as "AVID OP Atom Proxy Test.rar"
The rar archive includes the original file, transcodes highres files in XDCAM HD 50Mb MXF OP Atom and also 2Mb H264 Proxy MXF OP Atom files.
I seperated the qualities in different Media File folders.
Everybody who is familar with AVID Media File Folder structure should find the correct databases for dragging into bins.

The files are in a project 1080i50 created.
I tested to edit a sequence in proxy quality and than relink the sequence to the highres files.
This is working perfectly.

If someone could make proxies in this style for AVID he is a hero for actual home office editing needs.

Thank you all

Hi Hans,
so lets try to take care about this Avid Proxy stuff.
Unfortunately i have no avid for testing so it could take a while hehe... But i'd like to start with checking if the container generated by ffmpeg is ok.
On the share, in samples/AVID Proxy folder, i uploaded a remuxed version of the h264 proxy from you. Could you try if it works?

Thanks!

Hi All

I have tested it and unfortunately it doesn't work. The scan is ok but when you try to play it, it gives an error.

I tested the reencoded file you created.

The Media Composer scan the file without error message, that good.
But when the clip is in the bin and you want to play it, the error "MPEGMapper Segmented::CalcTemporalOffset: Did not find first temporal sample." like the other posts before.

Second thing is that the clip shows H264 800Kbps Proxy (HD1080p) in AVID MC bin, but it should be a 2Mb proxy from the data rate of the video stream.

I hope I could help with further details if possible.

Thank you for your help.

Hey @Hans
thanks a lot for testing out! You know, the fun thing is that i did not change the actual video codec of the proxy file, it was just rewrapped.
Fortunately @FranceBB and @momocampo also have Avid, they will help me with testing so we can speed this up a little bit.

From feeling it should do when we recreate some of the original metadata in the rewrapped mxf, i hope it is not too much metadata fields that we need to overwrite. I'll post here our results

@Hans
OK, we had a play now but it is really hard to recreate the MXF/AAF style that avid expects for the proxy.
After all it does not look like this is possible with the current ffmpeg opatom mxf muxer.

So, what we know by now:
Avid is compatible to the SONY proxy from XDCAM discs and of course to the proxies they generate on their own. I did analyze both but they don't follow any known to me standard.

How to got on from here:
Option 1) as stated before, someone who has the contacts should ask avid for the current AAFSDK source code. It looks like they did not publish it but as it is opensource, they must give it away without charge
Option 2) find more supported sources and post them for me for analyzing

Sorry for the bad news but looking at what i have now, i am just not able to trick avid into using ffmpeg generated files to accept them as proxy.

Hi

yes we have already discuss about AVID and their little secrets about AAFSDK. It seems that it would be difficult to obtain it.
Another way to go is to use MPEG2 instead of H264. You can generate MPEG2 Long Gop Proxy at 5 Mbits using the Generic MPEG node and rewrapp with BMX.
Of course it will not look as good as with H264 but it is a lot smaller that Dnx36 and It can help to speed up a home office workflow

bye

@Ghtais NICE addition
I have to excuse and correct what i said before: the license of the AAFSDK does not require AVID to share their modifications with anyone that asks (so it is not open-source) but instead they just must submit their source code 60 days before going productive with it to: Assumed this company is not owned by AVID, i wonder if it might be worth asking them for the source code that AVID submitted to them