RESET_9999 wrote: Fri Feb 21, 2020 8:05 pm
built_to_chill wrote: Fri Feb 21, 2020 6:23 pm
Hi all - I'm finding the MP4Box command runs extremely slowly (I dare say running in movie realtime). This is for adding the LPCM to the dual layer MP4.
It seems to hit a bottle neck when it comes to add the LPCM (after apparently reading in the two video layers normally).
Is this normal? Looks like it might take hours...
it all depends on the speed of your HDD / SSD.
With my PCI-E M2 SSD, it takes less than 10min building the final MP4 with LPCM
I figured it out. The problem was the Ubuntu version of gpac/MP4box.
When I copied the "no audio" MP4 and lpcm.mov files over to my MacBook Pro, and did the final MP4Box command using the Mac version of gpac, it ran very quickly. When it was adding the video tracks to the temporary ISO - this was very similar speed to on Ubuntu - but it didn't grind to a halt when adding the LPCM. And the ":rate=0" option works on the Mac version. No idea what is going wrong on Ubuntu but at least I have a workable solution now.
Just tried my first MP4 with dual layer Dolby Vision and True HD/Atmos as LPCM on the
X700 - Game of thrones Season 8 episode 1. As far as I can tell it worked a charm. Pressing info on the
X700 remote showed "Dolby Vision HDR" (as of course did info on my TV - a Sony AF9). And the audio was intact too.
Thanks again for sharing the information above.