View Bug Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0001390||DCP-o-matic||[All Projects] Bugs||public||2018-10-23 08:30||2019-01-07 12:30|
|Platform||Mac||OS||OS X||OS Version||10.12|
|Target Version||Fixed in Version|
|Summary||0001390: DCP-o-matic cannot handle some flavours of DNxHD|
A couple of DNxHD MXF files I've encountered come out very strange when encoded to DCP in DCP-o-matic 2.12.10.
The image appears blocky in a way that is not apparent when viewing the file in VLC or Adobe Premiere Pro.
ffprobe identifies the profile on both the offending files as "DNXHR HQX" - I guess a specific flavour of DNxHD.
This effect is seen both in the preview in DCP-o-matic and in the resulting DCP that DCP-o-matic makes.
ffmpeg is able to convert the file to e.g. ProResHQ without the artefacts appearing. So workaround is to convert file to ProResHQ with ffmpeg and make DCP from that file. That works fine.
Carl, I'll email you one of the files.
|Tags||No tags attached.|
|Estimated work required||Unknown|
Hi Jim, the file looks OK in 2.13.x so I think it's probably been fixed in FFmpeg. We could look at a backport to 2.12.x if it is important to you.
Believed fixed by FFmpeg updates.
Ah sorry I should have checked 2.13.x before posting the issue.
FFMPEG update: Ah that would explain why I've been able to use FFMPEG to transcode the files before sending in to DCP-o-matic.
Don't worry about a backport on my account. I'm coming to the end of my run of festivals for this year, so I'll just wait for 2.14.0 to be released.
Out of interest (and maybe here isn't the right place to discuss it), what modifications do you make to FFMPEG in your fork and why are they necessary?
And where is the git repo for your FFMPEG fork please? I can't find it on your Github. Or maybe forking FFMPEG is no longer required for DCP-o-matic?
The repo is here
The only really important change is one to provide access to EBUR128 analysis results in a sensible way. There's also a couple of small optimisations. Is should really just try to get them included in ffmpeg...
You should be able to build with stock ffmpeg but you will lose the EBUR128 stuff in DCP-o-matic.
|2018-10-23 08:30||overlookmotel||New Bug|
|2018-11-07 01:05||carl||Assigned To||=> carl|
|2018-11-07 01:05||carl||Status||new => feedback|
|2018-11-07 01:05||carl||Note Added: 0002755|
|2019-01-06 23:52||carl||Status||feedback => resolved|
|2019-01-06 23:52||carl||Resolution||open => fixed|
|2019-01-06 23:52||carl||Note Added: 0002861|
|2019-01-07 11:38||overlookmotel||Note Added: 0002864|
|2019-01-07 11:41||overlookmotel||Note Added: 0002865|
|2019-01-07 12:29||carl||Note Added: 0002866|
|2019-01-07 12:29||carl||Note Added: 0002867|
|2019-01-07 12:30||carl||Note Edited: 0002867||View Revisions|