DCP with CPLs with different audio tracks, Verify gives an error.

[dcpforever]

Hi.
I created a DCP with 7.1 audio for a film festival. As there were several screenings in different theatres, with 7.1 and 5.1 sound, I added a new playlist with 5.1 sound to the old DCP.
The new DCP works fine, but when I check it, I get this error:
‘The sound assets do not all have the same channel count’

This is normal, as it has two playlists with different sound tracks.
Shouldn't DCPOmatic Player take this into account so as not to flag it as an error?

[Carsten]

I haven't tried this before, it MAY be a bug on DCP-o-matic's verifier side.

You mean, you originally created a 7.1 DCP, an then created a 5.1 as an VF, reusing the original DCPs video?

If you verify the VF 5.1 version with the OV added, it may indeed be that DCP-o-matic falsely complains about the 5.1 audio track having less channels than the 7.1 OV track file. That would be a bug in verifier, because OV and VF clearly are allowed to have different channel counts. However, it may be that you made a mistake creating the 5.1 VF, and that there could be a mix of 5.1 and 7.1 tracks in your VF. That DCP would possibly play in cinemas, but is formally incorrect.

Did you verify the VF in Player, or in Verifier? Did you try to load ONLY the 5.1 VF and verify only this?

I assume you used a channel count of 12 for the 7.1 version? You may actually use the same channel count for the 5.1 VF, and leave the remaining 6 channels silent. 5.1 in a 12 channel track is perfectly legal. Some people suggest that for compatibility/workflow reasons, it would make sense to always use 8 channels (5.1 + HI/VI-N), or 12 channels (7.1+ HI/VI-N), because creating edits in the DCP later on is easier. I still see a lot of big budget DCPs with only 6 channels in the audio MXF, though.


Additionally - it is not formally incorrect to create the OV as 7.1 and the 5.1 as a VF - but it is better practice to create the 5.1 as default, and create additional sound mixes as VFs.

[dcpforever]

Let me explain better. I didn't create an OV and a VF, I only made a single DCP, but with two playlists (CPL). When I said ‘add’ in the first entry, I did so by creating a new DCP using two DCPs, the first with 7.1 audio and a new one with 5.1 audio, using CuteDCPTools. Sorry for the confusion.

In other words, the DCP contains the video mxf (four reels) and the two audio tracks, one with 7.1 (four reels) and the other with 5.1 (four reels).

In the player, I can select which CPL to play. Therefore, the Player knows that there are two CPLs when it comes to verification.

Same error in Player (Verify) and Verifier app.

Thank you.

[carl]

This is a bug, and it should be fixed in the upcoming 2.18.24. Thanks for the report!

[dcpforever]

Perfect. Thank you.