bypass j2c conversion?

[stereo3d]

First of all let me congratulate to this wonderful piece of software.
The amount of efforts, energy and knowledge in this work is absolutely amazing.
The whole system is very comprehensive and truly practical.

I would like to know if it is possible to feed already converted jpeg 2000 images as a source
and bypass the conversion step. I have a hardware j2k encoder and would like to
combine the workflow with DCP-o-matic.

It would be great if you could tell me how to do this.
Many thanks in advance.

[Carsten]

Are you sure your hardware J2k encoder creates proper cinema profile j2c files? If not, they will most likely crash the server or not work at all.

J2k for cinema has to follow specific constraints. OpenJpeg uses specific parameter sets.

- Carsten

[carl]

Hi,
Not yet, I'm afraid. That feature is on the way at some point fairly soon, though.

[stereo3d]

Are you sure your hardware J2k encoder creates proper cinema profile j2c files? If not, they will most likely crash the server or not work at all.

J2k for cinema has to follow specific constraints. OpenJpeg uses specific parameter sets.

- Carsten

Dear Carsten,

I bought a couple of years ago a FPGA based Encoder Card from INTOPIX. The company was very much involved in the development of OpenJpeg, as it is a startup of the University of Louvain in Belgium with close connections to XDC and Barco. Theses cards are often used inside DCI Servers as OEM product. I tried distributed J2K generation over Network. However with single files of about 12-16Mb for each frame, I faced technical limitations as the Network is the bottle neck. The card generates J2K files at about 30fps. I have been making DCPs since 2008 and never faced any problem. The card can do anything from lossless to whatever you want. DCI compliant or not. Especially working on longer movies this has proven to be very useful.
However since this is an OEM product, there is not really any software for operating It. I wrote a small software which can execute converting jobs for j2k. After that I would like to continue the packaging process with DCP-O-Matic.
Unfortunately I am not such a good programmer, but If I can support you with anything you might want to know about the process I will be glad to do it. I know how much work it is to do a software like this. And it is a pretty amazing job that was done here.

[Carsten]

There are other software packages which can use j2k image series. DCPC and OpenDCP for instance. But their general workflow is far from being as efficient as that of DCP-o-matic. Again, check if your hardware transcoder supports cinema profile j2c code streams.

http://www.openjpeg.org/index.php?menu=news

- Carsten

[stereo3d]

dear Carsten, somehow my last replay was not posted.
my j2c are 100% compliant.

[willyfan]

I have the same answer, bypass the jpeg2k encoding....

[carl]

This is now possible in version 2.0.22 (from here). At the moment the user interface suggests that it is doing colour conversion on the JPEG2000 files, but rest assured it is not (the data is being used as-is, provided no crop is specified). I'll fix that soon.

[willyfan]

Wow: I will try the feature ASAP!
I noticed that there is also an import dcp: when you import DCP, data will be re-encoded or not?

[carl]

I noticed that there is also an import dcp: when you import DCP, data will be re-encoded or not?

Not re-encoded unless you do something like cropping it.