PDA

View Full Version : How do you get 5.1 when beginning of stream isn't...



invader zog
03-06-2003, 10:41 PM
I have a movie that I am pretty sure the Tivo said was in 5.1. The first minute of the recording isn't the movie itself and isn't in 5.1.

I used Tytools in vpsplit mode and got the .m2v and the m2a file. When I load it into ifoedit, it says that the sound is "Dolby AC3 2ch 48kbs DRC"

I figure either:

1. I was wrong about the movie being in 5.1

2. The stuff at the start is screwing me up.

I tried running audiocheck, it just said "total chunks 1977"

Any suggestions?

BubbleLamp
03-06-2003, 11:14 PM
Originally posted by invader zog
I have a movie that I am pretty sure the Tivo said was in 5.1. The first minute of the recording isn't the movie itself and isn't in 5.1.

I used Tytools in vpsplit mode and got the .m2v and the m2a file. When I load it into ifoedit, it says that the sound is "Dolby AC3 2ch 48kbs DRC"

I figure either:

1. I was wrong about the movie being in 5.1

2. The stuff at the start is screwing me up.

I tried running audiocheck, it just said "total chunks 1977"

Any suggestions?

I think the latest vsplit jdiner released today is supposed to handle the switch from normal stereo to DD. But I haven't had the need to test this yet.

MrBassMan
03-07-2003, 09:24 AM
Alternatively, use tychopper to cut off the start of the stream.

AlphaWolf
03-07-2003, 10:08 AM
Just because you see the DD logo doesn't mean its in 5.1, if you notice it said AC3 2 channel. That just means dolby digital 2 channel, not surround.

captain_video
03-07-2003, 11:34 AM
If you're using tytool to extract just set a jump point about 60 or 70 chunks into the stream and you'll get the Dolby Digital with no problem. The intro to all DTV PPVs lasts about 30 seconds and is in normal mpeg layer II stereo so it won't show up as DD until you skip past that. Sometimes this confuses tytool because it tends to latch onto the first type of audio it detects. Setting the jump point to start the extraction at the beginning of the DD stream eliminates this problem.

invader zog
03-07-2003, 11:34 AM
The advice/help was appreciated. :)

ronnythunder
03-07-2003, 03:26 PM
another thing to watch for - when i ripped xxx the movie, the ppv intro was either mpeg or dd2.0, movie was dd5.1, and a bonus footage thing at the end was dd2.0, so it switched audio twice. tydemux just barfed completely, and vsplitmux2b choked until i started 58 chunks into the ty (i arrived at this number with some testing). at that point, the movie was fine, but the switch after the movie caused the bonus audio to be out of sync quite a bit. no big loss in this case, tho

ronny

invader zog
03-07-2003, 04:32 PM
The beginning of the movie says that it is presented in 5.1 where available. I assume that this means the broadcast was in 5.1, but I'm still only getting 2ch.

BubbleLamp
03-07-2003, 06:04 PM
Originally posted by invader zog
The beginning of the movie says that it is presented in 5.1 where available. I assume that this means the broadcast was in 5.1, but I'm still only getting 2ch.

But if you watch the lights on your DD receiver, you'll see the DD doesn't kick in until the movie actually starts. (If it really is DD5.1 that is.)

captain_video
03-07-2003, 06:46 PM
Hence the need to set a jump point so you begin extraction while actually in the part of the tystream that contains DD info.

ibsleepn
03-11-2003, 04:56 PM
I am trying to figure this out also. I can jump 1000 chunks into the movie but it still says that it is mpeg layer II audio instead of ac3.

I run audiocheck on Ballistic which was recorded on ppv. Supposed to be DD Surround but it say that it is mpeg layer II all the way to the end of the movie. Tytool 6r3 says the same thing even when I jump 1000 chunks into the extraction.

I know i get DD because i am extracting black hawk down which is DD 5.1. Can anyone lend any suggestions?

thanks..

ronnythunder
03-11-2003, 05:06 PM
ibsleepn, make sure that the movie really is supposed to be dd. the guide showed the ltbx version of bourne identity to be in dd, but it wasn't. i looked at directv's guide on their website and it did not say dd, in other words, the guide on the tivo was wrong.

ronny

ibsleepn
03-11-2003, 05:19 PM
At the opening credits of ballistic says that it is in DD surround. I have no other way of knowing as my reciever is older and doesnt tell me when movies are in DD or not. Hmm... other things to play with.. thanks for the reply....

captain_video
03-11-2003, 08:24 PM
Just because the DTV banner says it is supposed to be DD I've found that it's not always true. I've seen several movies that are listed as DD but in reality are mpeg layer II. If it doesn't play back as DD through your receiver or processor then it probably isn't DD. I just recorded The Bourne Identity the other day and it doesn't have a DD soundtrack even though it's advertised as having one. For the 1st day the sound was muted for every broadcast. When the sound was finally reinstated it was showing up as Dolby Pro Logic (analog) on my processor display.

I just checked channel 108 again and The Bourne Identity is again being broadcast with no soundtrack and my processor is indicating that it's Dolby Pro Logic. Ironically, the same movie is on channel 107 but the length is 2 hours and 1 minute while the letterbox showing on 108 is 1 hour and 58 minutes.

olaf_sc
03-11-2003, 09:01 PM
Have you set your DTivo to record and playback AC3 sound if not you will get MPEG audio and nothing else.

Cheers Olaf

PS: tydemux is automatically detecting what type of audio you have in the stream and extracts the right one.


Originally posted by ibsleepn
I am trying to figure this out also. I can jump 1000 chunks into the movie but it still says that it is mpeg layer II audio instead of ac3.

I run audiocheck on Ballistic which was recorded on ppv. Supposed to be DD Surround but it say that it is mpeg layer II all the way to the end of the movie. Tytool 6r3 says the same thing even when I jump 1000 chunks into the extraction.

I know i get DD because i am extracting black hawk down which is DD 5.1. Can anyone lend any suggestions?

thanks..

ibsleepn
03-12-2003, 08:19 PM
Yes it is set to record both. I have pulled DD audio off of it. Well i will just play some more... Thanks for the info guys..

invader zog
03-16-2003, 07:29 PM
I've tried another stream -- one that I know does 5.1 (I see the blue light on my receiver) but also has some intro stuff that is not 5.1.

In each case there is a few minutes of non-5.1 intro then the movie starts.

Processing 'file.ty':

Dolby Audio segment starts at chunk #: 1
LayerII Audio segment starts at chunk #: 12287
Dolby Audio segment starts at chunk #: 12289
LayerII Audio segment starts at chunk #: 16383
Dolby Audio segment starts at chunk #: 16385
LayerII Audio segment starts at chunk #: 17921

Total Chunks: 17928


and from another

Processing 'show2.ty':

Dolby Audio segment starts at chunk #: 1
LayerII Audio segment starts at chunk #: 4095
Dolby Audio segment starts at chunk #: 4097
LayerII Audio segment starts at chunk #: 8191
Dolby Audio segment starts at chunk #: 8193
LayerII Audio segment starts at chunk #: 12287
Dolby Audio segment starts at chunk #: 12289
LayerII Audio segment starts at chunk #: 14075

Total Chunks: 14080

jjjones
03-17-2003, 10:49 AM
Will Tystudio find the ac-3 stream without all this chunk work?

olaf_sc
03-17-2003, 11:11 AM
Yes, you can even try tydemux 0.4.2 it finds the ac3 streams for you to by probing the stream.

Cheers Olaf

rd001
03-18-2003, 12:08 PM
Sometimes, the guide lies about the Dolby tracks. And sometimes it claims one type of Dolby and you get the other kind instead. I think it's wrong more often than right.

You never know until the video actually starts playing/recording exactly which it is. Or if there even is a Dolby track.

invader zog
03-18-2003, 12:11 PM
So far the only method I've been able to get work is to manually tell it to start demuxing "x" chunks in.