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View Full Version : Compress Menu Audio (PCM->AC3) While Preserving Navigation


qyot27
26th July 2007, 03:43
I searched but I couldn't find something that addressed this specific problem.

I already had successfully followed this guide (http://forum.doom9.org/showthread.php?t=84887) (with some variations, such as using ffmpeg instead of BeSweet and only using Ifoedit rather than Muxman or ReJig - all of which were mentioned therein anyway), with other DVDs in the past, and even for this project it worked for the main titles.

My current issue is that these DVDs also use PCM audio for their menus. Normally I wouldn't think anything of it, but in these cases compressing the audio could make the difference of needing a single-layer as opposed to dual-layer DVD, and I also just wanted to optimize time for later burning.

Since PgcDemux has the ability to demux menus I simply used it the way the guide I already linked to describes doing with the main PGCs. I reassembled the video, audio, and subpictures in Ifoedit and then attempted to use Vobblanker's Menu->Cells->Replace option to switch out the original 99 MB menu for the 12 MB one that I had created simply by compressing the audio. It didn't complain and processed without errors.

When I went to test it in VLC (and later, after writing an ISO image, mounting it and trying MPC), I found that the menu's navigation buttons no longer register at all - no highlighting, nothing. I'm guessing either it's something in Ifoedit (as I'm sure it thinks the video, audio, and subpictures aren't a menu but a main title), or that I'm trying to make Vobblanker do something it can't.

Is there a way possible to do this or is this just something I'll have to live with, either with non-working menus or menus with PCM audio?

NOTE: The menus on these discs are still - they use what appears to be a full-length song, however.

Video Dude
26th July 2007, 03:52
I don't have a suggestion for compressing the audio to ac3 or mpa, but if you wanted to save space you could just strip the audio from the menu using a program like Shrink, setting it to no compression so the video is not touched.

blutach
26th July 2007, 04:23
Remuxing is not sufficient. You need to force the subpix and turn them on (as well as copying the CLUT from the original). Use DVDSubEdit to do this (see the sticky).

But, the easiest thing to do is use MenuShrink (http://www.dvdr-digest.com/software/menushrink.html) (which shrinks bloated menus to little stills).

Regards

qyot27
26th July 2007, 05:30
Remuxing is not sufficient. You need to force the subpix and turn them on (as well as copying the CLUT from the original). Use DVDSubEdit to do this (see the sticky).

But, the easiest thing to do is use MenuShrink (http://www.dvdr-digest.com/software/menushrink.html) (which shrinks bloated menus to little stills).

Regards
As I'd noted, the menus already are stills (and clock in at like 637 KB w/o audio) - they just have massive PCM streams attached to them.

I'll check out DVDSubEdit though - it is rather ironic, considering I had it on my computer to see if it could do something else related to this project, but ended up deleting it.

Thanks for the suggestions.

manono
26th July 2007, 08:02
Hi-
I found that the menu's navigation buttons no longer register at all - no highlighting, nothing.
See if the 1. Exporting and 6. Importing of this guide helps with your problem:

http://forum.videohelp.com/topic313743.html?sid=12c1c888d08133d6cfbac1efec366ad5#1606732

blutach
26th July 2007, 16:06
Yes, my mistake - you also need to import the button postions and highlight info, but of course need to ensure the highlights are turned on at the appropriate time.

Your method of course will work manono. :)

Regards

HFW
26th July 2007, 17:05
@qyot27
I think you could use numenu4u, which not only transcode or encode menus (which is not your case in this particular moment), but is able to transcode audio. Your PCM could be easily be encoded to a AC3 audio. Also, numenu4u have the capability of choosing the bitrate for the new audio in your menu. The rest of the files (movies + extras) are not touched.
I hope this help.

qyot27
26th July 2007, 18:29
Hi-

See if the 1. Exporting and 6. Importing of this guide helps with your problem:

http://forum.videohelp.com/topic313743.html?sid=12c1c888d08133d6cfbac1efec366ad5#1606732
This solved it, and works as expected now. Thanks.