The reason why the Blender JPEG2000s didn't work is beucase the encoding parameters are very strict. (just like when encoding h.264 for Blu-ray)Making it work shouldn't be too hard, I guess.What kind of sRGB to X'Y'Z' LUT does Blender have? The formula OpenDCP uses can be found in its source code btw. :)Did you actually have to do something to fix the out of sync issue? Assuming that the audio files were OK and the CPL had no offsets, did you have 2 frames too little at the beginning of the JPEG2000 sequence?Murphy's law can be killed by knowing who voted for it! (thus far my wisdom and intellectu ehhh brain farts! :P)Did you test different JPEG2000 bitrates? You're only using half of what's possible in a DCP. Don't forget it's 4K! ;)How satisfied are you with the results on the big screen?
Clique sur l'image pour mieu la voir. 
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