Is it possible to retain HD Audio when converting to BD9 in BDREBUILDER

[igotafeelin]

Each time I encode BD50 to BD9 using BDREBUILDER and select the True HD or Linear uncompressed Audio the completed movie has changed the audio to a compressed 5.1 DTS or Dolby track. Is this because there is simply not enough room or is it because AVCHD will only stream 5.1 I have just converted The Bank Job selecting the 7.1 track only. The picture quality is excellent but the audio has come out as DTS 5.1. Still excellent quality though. Probably expecting too much. i have tried all permatations in BDREBUILDER setup.

[jman98]

I'm sorry, but as I don't have a BluRay drive, I can't use this product, so I can't answer your question. I don't think there is any such thing as BD9. I think you mean DVD-9.

I find it odd that you and others have no problem compressing your video by 60% or perhaps even more to make it fit on a DVD-9 disc, yet you act like someone is threatening to cut off your arm when you (gasp!) don't get full HD audio. HD audio formats take up a lot of space, which is probably why BDRebuilder (presumably) doesn't save them in the output. If you want to squeeze BD output down to DVD-9 size, then in my opinion BDRebuilder is quite right to not give you an option to save the HD audio. Do you really want to squeeze the video by 80% or more just to fit in HD audio?

[igotafeelin]

Thanks for your comments.
All I was looking for was a simple answer yes you can or no you can't.
BD9 does exist bye the way. It is a blu-ray (AVCHD) format recorded to a Dual Layer DVD & will only playback on a blu-ray player.
You should also check out the video quality before you knock it as it is excellent & with blank BD25 discs in excess of £2 & DVD9 @ 35p it makes a good sense to record to BD9 for some movies. Just be even better with HD Audio.
But hey its no big deal.

[fritzi93]

Yeah, BD-9 means AVCHD on a dual-layer DVD. And it's amazing how good the quality is, even down to ~ 4 Mbps. You can do main movie, and re-encode the audio to AC3 448 kbps and usually get to 4 Mbps bitrate or better for the video on a single-layer BD-5. I'm not gunna say it's indistinguishable from the original, but it's quite good.

As to the OP's question: Since True HD audio is optional in the Blu-Ray spec, there must also be an AC3 track present. Anyway, as you can well imagine, the video bitrate would really suffer. Bitrates for TrueHD are as high as for LPCM, i.e. it take a good deal of bitrate, if I'm not mistaken. My own opinion is that inclusion would defeat the purpose of rebuilding a movie to fit a BD-5/9. But go to the author's website and read the bug report thread. (Click on BDRB, go to author's site). If memory serves, your question comes up in the thread.

But now that I think about it, one of the first rebuilds (with an earlier version of BDRB) I did came out with LPCM audio. It was at the top of the audio list, and I did not specify re-encoding the audio in setup. That put the video bitrate down to ~ 3.6 Mbps. You do a 10-hour re-encode and find out you have to do it over. :P

That's how I see it, although I'm open to being corrected.

[EDIT] Isn't AVCHD limited to one audio track anyway? I'll check on it.

[fritzi93]

Well, it seems AVCHD is a nebulous subject. Maybe it's because AVCHD is the red-headed stepchild of Blu-Ray. :P

It arose from HD camcorder usage. Implementation varies between brands: i.e. Sony uses Main-Profile@ Level-4.0 for a maximum of 17 Mbps, some Panasonics use 4.1 up to 24 Mbps.

For playing on a home set-top, it seems it comes down to what your player will accept. My Sony plays it all: AVCHDs made with TotalMediaExteme from HD caps, multiAVCHD discs, BDRB discs, with or without the index file being patched. Discs burned with or without the Certificate folder. There's a lengthy thread at Doom9 on what various brands of players will accept in the way of AVCHD structure. Support varies widely. I mean widely.

Uncompressed LPCM audio is supposedly *NOT* supported. That disc I made with LPCM audio? The Sony plays it.

Hell, I don't know. Maybe edDV will kindly explain it all?