Using mxf timelapse files in PPro CC

[Alan Emery]

I am having troubles with PPro CC importing my mxf timelapse files that were recorded using a nanoflash. The files are all 100mbps and all work fine in PPro CS6. (I have no trouble using regular mxf files recorded on the nanoflash in PPro CC). PPro CC reports an error decoding the timelapse mxf files. It handles the first few frames without difficulty, but then gives me a bright red screen - scary).

I also tried ingesting it into Prelude, but had the same problem. I tried some mxf to mov converters, but the ones I tried all worked but with considerable loss of information (typical 300 MB file reduced to 25 MB file).

Any suggestions would be welcome, including a converter that will retain the bitrate on conversion. Many thanks in advance.
Alan

[Dan Keaton]

Dear Alan,

I will alert our team.

And we can report this to Adobe.

Respectfully,

[Dan Keaton]

Dear Alan,

Do regular, non-timelapse MXF files work in Premiere Pro CC?

I have alerted our support team.

Respectfully,

[Alan Emery]

Hi Dan,

I should note that I am not alone in experiencing "red frames" in PPro CC with mxf files from any source. It appears to be a random fault and has been a headache for delivering a clean final to clients. The problem is also present in Prelude and After Effects. In the Adobe forums there are many workarounds that sometimes work and sometimes do not work. I have not found one that works for me. The files can be converted to another codec if you have a converter that is lossless. I can't find a good one for a PC with Windows 7. A trial with a freebee converter worked well (loss of information was too much though) and the resulting mov file worked fine in PPro CC.

The regular nanoflash mxf files work fine in PPro CC for me.

The timelapse mxf files from the nanoflash work fine in PPro CS5 and CS 5.5. They only have problems in PPro CC. The first few frames are OK then the rest are brilliant red.

A simple solution for the future with a nanoflash is to record in mov format, but Adobe will need to address this for mxf files as it is a very common format for professionals.

[Dan Keaton]

Dear Alan,

Thank you for the update.

Our regular and timelapse files should be the same.

I am curious, for your timelapse files, are you using our I-Frame Only or Long-GOP?

I-Frame Only would work better for timelapse.

We have both Mac and PC versions of our file converter that converts our MOV files to MXF.

And Sony has a program (for the Mac) that converts MXF to MOV.

But, we do not have a PC based program to convert MXF to MOV.

Since our timelapse files work well in versions other than CC, I currently feel that our files are ok.

And yes, I agree that just recording in ".MOV" may be a simple workaround for now.

Respectfully,

[Alan Emery]

My timelapse is usually in long-gop format, but sometimes in I-frame only. Both seem to work equally well in the previous versions of PPro. It is only on switching to PPro CC that the problem has come up.

I personally agree with your logic that because the files work well in other versions of PPro, the problem is undoubtedly with PPro CC, not the nanoflash files. When I first posted the question, I had no idea what was going on so wondered if it was the nanoflash files. I have now found the problem is widespread beyond nanoflash files and under discussion in other forums as well.

I also found a solution for converting mxf to mov files (although I should not have to do this to use mxf files in PPro CC). Black Magic DaVinci Lite (a colour grading software) is free and has a handy file converter that preserves the quality.

[Dan Keaton]

Dear Alan,

Thank you for the update.

Respectfully,

[Alan Emery]

Hi Dan,

A further update - this time it also affects the nanoflash. I normally leave the setting for timelapse as "long GOP". According to Adobe, the files I have recorded from the nanoflash as timelapse recorded as long GOP are actually I-frame-only. The header on the clips, however, shows long GOP as the format, even though it is actually I-frame-only. In previous versions of PPro CSx the software ignored that discrepancy so they decoded fine. However in PPro CC, the software is more discriminating and hangs up on the discrepancy producing red frames.

Adobe is working on a fix for this, so the timelapse clips should work when the next version of PProCC is released, but I don't know when that will happen.

In the meantime, it is possible to transcode the mxf files to mov (using a converter - I use the DaVinci Resolve converter) and use that in the PProCC sequence where it works fine.

Also in the meantime, you might think about having timelapse function on the nanoflash write I-frame-only to the header even if the operator gets it wrong (GUILTY) and leaves it as long GOP when switching to timelapse. I wasn't able to check and see if the timelapse function correctly writes I-frame-only to the header if the setting is correctly set to I-frame-only on the nanoflash.

Kudos to Adobe for jumping on this right away and I hope scheduling the fix to be included in the next version of PProCC.

Alan

[Dan Keaton]

Dear Alan,

Thank you for your update.

Background:

Our I-Frame Only, is a Long-GOP format, but instead of having I, P, and B frames,
each frame is an I-Frame. That is why we call it I-Frame Only.

We recommend, when recording time-lapse, to set the nanoFlash to I-Frame Only.

In any case, even if you set it to Long-GOP, for Timelapse, internally, we record I-Frame Only.

(Long-GOP does not make sense when there could be seconds, hours, minutes or days between each frame, as there may not be much similar from one frame to the next.)

I have noted that you have requested us to make the change in the header.

I would be interested if you recorded a test, setting the nanoFlash to I-Frame Only, then recorded a timelapse clip, then testing in in Adobe CC.

Respectfully,

[Alan Emery]

Hi Dan,

I don't quite follow the logic of how an I-frame-only can also be a long-GOP format even if there are no P and B frames. And as you note and the Adobe people discovered, even if the nanoflash is set to long-GOP, the nanoflash records I-frame-only in timelapse mode. That part is quite logical.

Given that the Adobe team is willing to add a fix so that even if the header settings are not consistent with the actual structure, it will still decode properly, and given also that a transcode by DaVinci Resolve from mxf to mov solves the problem, the situation is not urgent. My suggestion was only to eliminate the difficulty of there being a discrepancy that future software developers will need to take into account for nanoflash timelapse video taken on the wrong (long-GOP) setting.

I will do the test for you and report the results - it might take me a couple of days to get to and to complete the test.

Best,
Alan

[Dan Keaton]

Dear Alan,

In our I-Frame Only mode, each frame of video is compressed individually, as opposed to in Long-GOP mode where the contents of the previous or next frame of video is used to achieve a higher compression, or lower bit-rate without sacrificing quality.

We record in Sony XDCam format, which is always a Group of Frames, 12 for 720p or 15 for 1080.

Thus, for I-Frame Only, we fill up the Group of Frames with all I-Frames.

I hope this helps.

Respectfully,

[Alan Emery]

Hi Dan,

Intriguing. So you suggest the long-GOP format in the header is correct even though the recording is in I-frames-only - because the I frames are grouped. I will let Adobe know so that they can make sure they test the fix with that in mind.

Out of interest, does the Sony XDCam format in I-frame-only format in nanoflash timelapse retain the long-GOP format or does it shift to true I-frame-only?

Many thanks,
Alan

[Alan Emery]

HI Dan,

I ran the test for you. The nanoflash set to timelapse with "I-frame only" decodes just fine in PPro CS5, but hangs up and produces red frames in PProCC. The implication is that no matter how one sets the nanoflash (I-frames or long GOP) the nanoflash always sets the header to long GOP. This is why the PProCC can't decode it properly.

Hope that helps,
Alan

[Dan Keaton]

Dear Alan,

Thank you for testing this for us.

Yes, that helps.

Respectfully,