Audio Stream detection setting

MrVideo

Active member
I've been working on projects where I have both DTS and AC3 audio streams. In the file, the DTS stream is first. I want to keep it that way, but when the file is loaded into VRD, the AC3 stream is selected as the primary, resulting in the audio streams being switched when the file is output.

I need VRD to select the first audio stream as primary, no matter what it is, so that the audio stream order is not screwed with on output. Is there a way to do that?
 

Dan203

Senior Developer
Staff member
What kind of output file?

The only output file types where we do anything to promote the "primary stream" are WTV and MKV, both of which have a primary stream flag. For all other formats audio streams are output first come first serve and their stream IDs are maintained.
 

MrVideo

Active member
TS. The TS files were created with tsmuxer, where H.264 is first, DTS 2nd and AC3, 3rd. When brought into VRD, AC3 is selected as the primary stream, even though it is listed as the 2nd audio stream. When the DTS stream is selected as the primary and the file output as MKV, when read back into VRD for verification, DTS is selected as the primary audio stream.

This applies thru 758b. I haven't loaded 766a on the XP box yet. I have it on the Win7 box, but have not tried it there, as the work is being done on the XP box.
 

Dan203

Senior Developer
Staff member
You're running into a couple of different things here.... with TS VRD detects streams first come first serve, so the order of the lists is determined by the TS mux and which stream has a packet appear in the TS first. The primary stream favors AC3 by default. There is an option in Tools->Options->General to set the preferred type, but we never added DTS to the list because we were never able to fully support DTS-HD. As mentioned above MKV and WTV have a special flag you can set on a stream so that even if it's not "first" it's still the one selected by default by players. We set this flag on the "primary stream" when saving to MKV which is why the DTS stream is selected even though it's actually second on the list.

The only way to physically rearrange streams is to use Pro.
 

MrVideo

Active member
The audio streams are in the file in the desired order, i.e., DTS is first. VRD shows that it is first, but as you indicated, it chooses AC3 by default, even though it is 2nd in the list. I was hoping that there was a flag that could be set that says to chose the first audio stream, no matter the type. In this case, it is plain old DTS. I'll just have to keep selecting the DTS stream manually before creating the MKV file.

But, VRD does rearrange the audio streams. If I forget to flag the DTS stream, the MKV output will have the AC3 stream first in the file. Both MediaInfo and VRD verifies that.
 

Dan203

Senior Developer
Staff member
Actually you're right. We do rearrange the streams so that the primary stream is always first. That's so that most people get what they expect, which is the primary steam playing when they play the output in another player.

I think there is an option to turn that off though. Not at PC at the moment, but I think it's in Shift+Tools>Options.

We don't have option to select DTS as default because as I said we can't fully support DTS so we didn't want to promote it too much. (there is a very complex issue with how DTS-HD audio is atored in TS that we can't fix without a major overhaul of our TS reader and other code)
 

Dan203

Senior Developer
Staff member
I just checked the code and the way to prevent the audio streams from being reordered is to switch the profile audio mode over to "advanced". By doing that we assume you've arranged the streams how you want them and leave them alone. But the default when you simply click the radio button is to put the streams in the same order as the input file. So all you have to do is change the mode and it should work like you want.

Although with MKV I think the primary stream will still get "flagged" in the container, so that may affect some players.
 

MrVideo

Active member
But the default when you simply click the radio button is to put the streams in the same order as the input file. So all you have to do is change the mode and it should work like you want.
Sorry, but clicking on the Advanced radio button brings up the list of the two audio streams and they are not in order they are in the file. They are arranged with the Primary audio stream first. If I do Tools->Select Streams and select the DTS audio, then the order is the way I want it. But, no matter what, the order is rearranged, unless I manually intervene.
 
Top Bottom