Audio Stream IDs

[knudman]

Hello everyone. I am currently writing an IFO application that will allow modified video and audio streams to replace the original ones. I had a question that I couldn't find in the DVD Specifications put out on sourceforge, or in IFOEdit. Does anyone know where in the IFO the Audio Stream IDs are found. I thought it was in the VTS_PGCITI (Video Title Set Program Chain Information Table); however, on the Blade2 DVD the second audio stream in the IFO is a DTS stream and it has the stream ID 0x89. Which doesn't corespond to the VTS_PGCITI table. I know you can get this information from the VOB files, but I was assuming you could get it from the IFOs as well since IFOEdit shows the stream IDs. Anyway, I would appreciate anyones feedback on this. Thanks.

[GZZ]

You CAN'T find the Audio Stream ID in the ifo file, you have to 'calculate' this...It goes like this:

AC3 = 0x80 -> 0x87

DTS = 0x88 -> 0x8f

I can't remember LPCM and MPA audio ID, but they are coming after DTS


so if you parse your ifo file for audio streams then the first Audio stream will be 0x80 (if AC3), if the next is DTS, then it will be 0x89, because its incrementing the counting by one, like if audio stream 3 is AC3 it will be 0x82... I hope you understand my proberly bad explenation...

Example (just an example I made up)

Audio1: AC3 - Hex: 0x80 - Byte Value = 128
Audio2: AC3 - Hex: 0x81 - Byte Value = 129
Audio3: DTS - Hex: 0x8a - Byte Value = 138
Audio4: AC3 - Hex: 0x83 - Byte Value = 131
Audio5: DTS - Hex: 0x8C - Byte Value = 140
Audio6: AC3 - Hex: 0x85 - Byte Value = 133
Audio7: AC3 - Hex: 0x86 - Byte Value = 134

and so on


I hope you understand it...


GZZ

[Vladimir]

I suppose. ID = BaseNumber + (nStream-1). In your example DTS Stream is second stream ID = 0x88 + 1.

[jsoto]

These are the index I know
0x80-0x87: ac3
0x88-0x8f: dts
0x90-0x9f: unknown
0xa0-0xa7: lpcm
0xa8-0xaf: unknown
0xb0-0xbf: unknown
0xc0-0xc8: mpeg1
0xc9-0xcf: mpeg2
0xd0-0xdf: unknown
0xe0-0xef: unknown
0xf0-0xff: unknown

As you can see, the "simple index" (between 0 and 7) is made using the three lowest significative bits

BTW, could you explain a little bit what you are trying to do? Remux a stream in a VOB is not easy...

jsoto

[knudman]

Thank you, this is exactly what I need. That makes a lot more sense. To explain what I am trying to do. I use a combination of doitfast4u, ReAuthorist, BeSweet, Premiere, IFOEdit, IFOUpdate to tear a DVD apart. I then edit the movie content in Premiere and then put it all back together so that the DVD has all the chapters and menus. This is quite a process so I wanted to develop an all in one solution kindof like Doitfast4u but setting up the video and audio streams to be edited in premiere and then building the DVD again with the modified streams. I don't know if that makes sense but it would save me a lot of time. I have figured out most of the IFO stuff, but the more complicated stuff: VOB Remuxing, AC3 transcoding, stuff like that I am going to leave to the pros. Kindof like Doitfast4u does. Mine is mostly a GUI with IFO parsing and rebuilding capabilities. Thanks.

[GZZ]

why use premiere ?


Scenarist are normally used to authur a DVD, also don't see the point in besweet...


GZZ

[knudman]

The purpose of premiere is to edit the actual movie. Take scenes out, modify the audio, etc. I use besweet to decode the AC3 surrond files into wav files to import into premiere. Then I can modify the audio and Video (with the help of avisynth) reencode using Premiere's MainConcepts MPEG exporter and Surcode's AC3 encoder. I then have to modify the Scenarist script generated by ReAuthorist to import the modified video and audio streams. I only do it this way when I want to edit the movie.

KNUDMAN

[GZZ]

ok I just didn't understand why you edit the movie, are inserting your own effects or cutting it like you want it to be ??

Maybe I´m just stupid and asking to many question...But just didn't get the point in editing a original movie in premiere...I normally just used scenarist and then add chapters and subtitles and audio language...


GZZ

[knudman]

It's big here in Utah. You edit out swearing, sex scenes, explicit violence. Sort of like creating a PG-13 version out of a rated R movie. That way people who don't want to see that stuff don't have too.

[GZZ]

its a joke right ?

are you somekind of super christian, who find sex scene as something forbidden or what ??



Its the must funny thing I EVER heard...lol

but good luck on editing almost all the movies in the world... :D


GZZ

[knudman]

It's not a joke!

You don't have to be a super christian to respect others rights to watch what they want to watch. (I figured someone from doom9 would understand that)

"but good luck on editing almost all the movies in the world... "

Not quite.

[GZZ]

it was a joke, but never did understand why!...Anyway good luck on your project...Just write if you need more help.



GZZ

[knudman]

Thanks

KNUDMAN