I am unable to see in the example app code - or any of the base libraries - where you are able to add a timecode track in to the new AMT clip that you are writing.

I am doing AMT -> AMT encoding (uncompressed to compressed) where my source AMT asset has timecode both in the XML and on the OPAtom.

My new files that I am generating do not contain any timecode track at all - and I dont see how this would be added in the AMT code.

In the code in the sample app I see it using a function called GetMobIDs - but this is only ever called on the source media AMT session, and never passed through to the destination media AMT session.

Please can someone confirm how you get AMT to create a timecode track - and how one passes in the timecode you want it to start with?

Hi James,

You can specify start timecode and drop frame in the specification XML as shown in the attachment.

AMT does not create timecode track in this case, its metadata only.

Thanks - this makes sense for interplay check in - but for standalone media composer implementations this is obviously an issue.

Are you able to suggest any other tools other than AMT we can use to add a timecode track? The media I am looking to support is JFIF 4:1s which is not a recognised essence type by such libs as libMXF and so I am not able to use any of their tools to rewrap to add timecode.

Could you please describe what the issue with standalone MC is?

AMT generates AAF for MC to open.

The issue is that when opening the media in MC - it shows as having no timecode track. Similarly the media in say MediaInfo shows as having no timecode track.

If the media is opened via the AAF - are you suggesting that it would show as having a timecode track in MC?

Here is the example, opening AAF gives the start timecode as specified in the XML file:

I have suggested this back to our client - and have received the following reply;

"...This wouldn’t normally be the case with Avid media.

 When generating media via any solution to Avid OPatom, the TC would definitely be baked into the file.

 As AAF delivery across platforms is not always guaranteed and sequences can modify the metadata it is imperative that it is baked into the file itself, not just as loose metadata in the AAF..."

I have to agree - it seems less volatile to actually embed the timecode into the offline proxy, given its importance when linking media.

Can you confirm if there is any means to do this within the AMT DLL or the associated DLLs (e.g. AAF libs, etc.)?

Hi James,

I'm still not sure what the issue is. Please describe the import workflow for AMT generated media.

Using Media Tool also works as expected and start timecode is shown as specified.

Also what do you mean by offline proxy? What is the "any solution" used to generate Avid OPAtom media you're using?

I'll clarify which timecode MediaComposer displays as TC1 track and let you know if AMT can generate that if that is the question here.

The workflow is the OPAtom media will be ingested via a referenced an AAF file - and so of course the AAF file can contain the timecode track for the OPAtom.

However - we are wanting to keep this secure, and so we need to have the timecode stamped onto the file.

If we look at a file export to JFIF from Avid Media Composer - we see a timecode on the file...

However if we look at a JFIF file made by AMT - we see the absence of the timecode stamp;

This is what we need adding on the files as a minimum.

Hi James,

Which tool are you using? Simply looking into MXF dump you can find start position as shown below:

Well Media Composer critically - it shows no timecode.

But then also MediaInfo, FFMPEG, FFMBC - none of these show a timecode stamp.

James, please provide a screenshot of MediaComposer not showing the timecode. I can see it in my lab.

Hope you understand we are not in control how the other mentioned tools handle and read metadata.

Understood - my only interest here is MediaComposer showing the timecode.

To confirm - the screenshot you provide was achieved by adding in the OPAtom directly - without adding in the associated AAF?

I will repeat my tests tomorrow and confirm - providing screenshots.

Yes, this is media tool view. MXF file is directly indexed by MC no AAF involved. You can see both source and master mobs show the start timecode.

Vadym,

For now I have resolved this using the libmxf tools, compiling our own version of BMX that supports the required JFIF variants that we are using (e.g. 4:1s).

I am doing some other work on getting the metadata updated for AMA linking, and so will publish here my final OPAtom for reference when I have completed it.