Dolby DSS200 and test version

[carl]

Hi Carsten, excellent work, can you send me the files?

[carl]

The 4K fix was also in 2.11.23 but I'm 99% sure that's not it as there should be no difference in the code for 2K.

[carl]

Files received, thanks Carsten. If you could test 2.11.34 (which is on its way up at the moment) that would be great.

[Carsten]

Hi Carl, just sent the ZIP to you. I guess not many are able to follow my experiments, but guess you are...

I have been using BigBuckBunny for my tests, creating Bunny2105 and Bunny21131 DCPs using DOM 2.10.5 and 2.11.31 on a WIN7-64 machine (installs/uninstalls/reinstalls with config recovery).

When the 2.11.31 DCP wouldn't play on our Barco, I first tried to reuse the J2C MXF from the 2.11.31 DCP in a 2.10.5 DCP. That wouldn't play either. I then extracted the same j2c frame (#560) from both MXF files (2.10.5 and 2.11.31) to compare them - which showed the two small differences in my diff tool.

A few minutes ago, I also did another test - I loaded those two single frames (one encoded with 2.10.5, one with 2.11.31) into DOM 2.10.5 as still images, and created 30s DCPs from them (expecting that DOM would again pass through and copy them unaltered). So one DCP per frame. I unwrapped the resulting MXFs again and expected to see identical data and identical differences between the frames (now all identical frames) - which came true.

Of course I also tried to play these DCPs on the Barco, and as now expected, the still DCP created from the 2.11.31 J2C frame would not play, while the DCP created from the 2.10.5 frame WOULD play, although both DCPs/MXFs had been created with DOM 2.10.5, but the J2C from two different versions. So it appears evident that structure changes within the single J2Cs are causing the issue. That to exclude wrapping or other reasons on a higher level.

- Carsten

[Carsten]

Files received, thanks Carsten. If you could test 2.11.34 (which is on its way up at the moment) that would be great.

I have the Barco running at the cinema and can connect to it remotely, so I can perform test runs from my sofa, waiting for 2.11.34 to show up...

Happy New Year!

- Carsten

[carl]

Happy new year to you too! Great, I will push the Windows 64 build of 2.11.34 to the top of the pile so it should be there within 15 mins or so...

[carl]

There she blows...

[Carsten]

GOTCHA!

2.11.34 Bunny plays fine on Barco. No issues at all in playback log.

Of course I can't see picture or listen to audio remotely, but in this case, the playback module screen shows enough to be sure there is a change. With 2.11.31, the playback wouldn't even start, or jump around and stutter.

Will make a few slides tomorrow and check them on Sony and Barco. Someone with Dolby DSS server should test as well.

- Carsten

[gunnar]

What I found quite disturbing is that our Barco sometimes refuses to play (immediate stop at 00:00:00), but sometimes will play, but with stuttering, dropped frames etc., and all using exactly the same files and procedures. But, what gives...

I didn't try wether 4k makes a difference. Carl, I understand there was not just a change to the 4k wavelet level scheme in 2.11.23 (http://dcpomatic.com/mantis/view.php?id=1125), but a new version of openjpeg. But is it possible that the additional 6th level for 4k is now also created in 2k, thus confusing the decoder?

- Carsten

Yes this is exactly the same on the DSS200 dolby server. It just sometimes wont play and stop at 00:00:00 and maybe after 10 seconds it starts for few seconds and stop again.
And again, the DoReMi IMS1000 have no problem with it, everything there play as it should.
I have even updated the software version on the DSS200 to the current 4.8.10 (4) and it made no difference. Still the same playback error.
And good to know about the Barco server, so this is happening on more servers than the Dolby one´s.

Edit:
I did not notice the new version is out, i am testing it right away on DSS200 and see if it is still problem or not.

[Carsten]

Carl - do you know what this ill fated openjpeg commit was targeted at?

- Carsten