Video .xml editing?

Anything and everything to do with DCP-o-matic.
Cayuela
Posts: 2
Joined: Tue Jul 12, 2016 9:00 pm

Video .xml editing?

Post by Cayuela »

Hi everybody! Please I need advise, from an existing Dcp it is possible to create a new one editing de video.xml file?
My client wants to substitute four new shots in differents places on the existing Dcp I created, my questions is if as it is possible to add subtitles to an existing dcp and create a new one, do you know if it is possible to insert 4 shots into a an existing Dcp and creating a new one without having to render again all the jpeg2000? Thanks!
Carsten
Posts: 2668
Joined: Tue Apr 15, 2014 9:11 pm
Location: Germany

Re: Video .xml editing?

Post by Carsten »

Technically, it is possible to add subtitles to an existing DCP with DCP-o-matic. That is, if you were careful enough to not create an encrypted DCP. Even with an encrypted DCP, it would be possible if you were careful enough to save the key(s)/Metadata, or create DKMDs.

Adding some shots on the DCP level would be possible, but I don't consider it a good idea. Doesn't the client have this project still available in the video editing system is was created with?

I sometimes edit out parts of existing DCPs, but I don't know if DOM currently supports this without re-encoding. It will become tricky if audio needs to be resynced and all. Techwise, it is absolutely possible to add another MXF containing the added shots and edit the CPL to include them. But as I said, this can be very tricky in reality. A video editor is better suited to this task.

- Carsten
Cayuela
Posts: 2
Joined: Tue Jul 12, 2016 9:00 pm

Re: Video .xml editing?

Post by Cayuela »

Thank You Carsten!
The original Dcp was made 6month ago, now the Documentary it´s been selected into an important Cinema Festival and they demand Spanish Subtitles on it, so my clients also wants to change few shots on purpouse for this festival, this is why I was wondering if I could avoid to re-do it again editing the .xml
I´ll take your advise, I won´t get in trouble making experiments and I will aski the client to send me again the new time line to export
a new and original Dcp. Cheers!
scorpio81
Posts: 116
Joined: Mon May 09, 2016 7:19 am

Re: Video .xml editing?

Post by scorpio81 »

Yes, adding insert shots manually IS tricky but also IS challenging at the same time.
Technically it is possible for unencrypted and unsigned DCP.

So the original timeline (reel1) would change to: reel1 (original) --> reel2 (insert) --> reel3 (original) --> reel4 (insert) --> reel 5 (original)..., where insert reels replace parts of the original reel.

Basic steps for adding insert shots (without altering or resynching audio track) would be, I guess:
1) generate video mxf for each insert shot with the same package type and aspect ratio as the original;
2) calculate MD5 checksum for each mxf and convert it to Base64;
3) insert these new assets to Assetmap and PKL (there are online services that can generate UUIDs);
4) find out the exact entry points for each reel - original and insert; determine durations for each reel so that total duration for original reels (keep in mind that one original reel is splitted into several) and insert reels is exactly the same as the duration of original unsplitted reel.
5) insert these new reels into CPL; audio is the same for each reel and just have various entry points equal to those for video reels.

It seems very tricky but will become much clearer if you carefully examine any movie DCP with insert reels - i.e. dub cards, titles and writings in different languages and so on.