No DTS Passthrough with AC3Filter

[TwistedMelon]

System: Zotac Zbox Nano AD10 with AMD E-350 using integrated Radeon HD 6300 HDMI graphics/audio.

Windows 7 Ultimate SP1

All drivers should be properly installed, including the addition of the Realtek ATI HD Audio driver which makes the HDMI audio work - HDMI audio doesn't work without this.

Full SageTV 7.1.9 running in client mode. EVR renderer, Microsoft decoders, audio rendered Realtek/ATI/AMD HDMI, decoder AC3Filter.

Running AC3Filter 2.5 (latest) lite version. Set up for SPDIF with all passthrough options set. AC3 seems to pass through correctly. AAC seems to decode and go through as PCM correctly. DTS produces no output.

There are no other optional audio nor video decoders installed on this system. The external audio/video hardware is known to be configured correctly as everything works fine using either HD200 or HD300 Extenders.

Using the AC3Filter configuration panel it's impossible to see if it's working, even when not using passthrough an forcing down-conversion and re-encode, I can't see any action in the input and output meters. Also, changes to AC3Filter seem to require a system restart to take effect. Restarting SageTV alone doesn't seem to work. Example, if I have passthrough working, then I turn off AC3Filter or set it to down convert, restarting SageTV continues to pass through AC3. After system restart I can see (hear) the new settings.

I've searched the forum and found a number of very old threads, none of which seem to have helped here in this situation. I don't think I found anyone that had only DTS passthrough not working.

Any help greatly appreciated. I'd really like to get this system rock-solid and this seems to be the last missing piece (for now anyway)

[Fuzzy]

What hardware are you connected to? It's possible that the hardware isn't reporting that it supports DTS decoding (most TV's do not). Pesonally, I'd rather send out uncompressed PCM if your hardware supports it. Have AC3Filter, or ffdshow decode and output the PCM. This also allows for volume control through sage, if so desired, and some other nice features, like DRC.

[jorton]

Open up the sagetvclient.properties file and search for a line with DCA in it in the audio codec area. Make sure it is set to ac3filter if it is blank. I'm not at home so I can post details later.

EDIT: look for "videoframe/dca_audio_decoder_filter=" and set to be the same as "videoframe/audio_decoder_filter=" depending on if you use ffdshow Audio Decoder or ac3filter Audio Decoder.

I never get passthrough of DTS on my MKV's unless I set this with AC3filter or FFShow Audio Decoder. DCA is how Sagetv reports DTS in the file info's.

J

[TwistedMelon]

Fuzzy - Sage/AC3Filter don't care about the HDMI EDID reporting available audio modes. Windows reports that I can only output 2 channels, but that's because of the way my equipment is connected:

Client connected via HDMI to DVDO Edge video processor. Processor connected to TV via HDMI for video ONLY and to Audio Pre-Amp/Processor via Optical for audio. Since the DVDO passes EDID from the TV to the source device (client PC) it sees only 2 channel.

But I can confirm that multi-channel works fine because AC3 is passing through correctly. AC3Filter is absolutely needed for this, as SageTV without it eithr produces no audio at all or is limited to what the system provides, 2 channel.

Jorton - I'll definitely take a look at this later today. It's a pity there isn't better audio integration right within the SageTV UI.

Off on a tangent now... IMO, the client software is simply not feature complete having to rely on so much external software and variables. This makes setup a very hand-on intensive building process, rather than a consumer approach that the extenders allow. Definitely why desktop-based DVR software and clients have never really caught on. It's a real shame that Sage wasn't more widely known/publicized as the server-extender model was a great setup and only about to get better with Sage's unreleased stand-alone PVR box. Damn you Google.

[Fuzzy]

The TV's EDID probably DOES include AC3 decoding though, as most all tv's do support AC3, as that is what is in broadcast television.

As for sage being 'feature complete', that is not the job of sage. DirectShow was designed to handle everything for every media application, through it's auto-graph building. If 3rd party directshow filters were actually programmed properly (which virtually none are), no media playback app should ever have to even know what codecs are being used, or even what format the video is.

In short, SageTV just didn't go as far in micromanaging workarounds for the failed directshow graph generation system using faulty filters - which isn't MS's fault either...

[TwistedMelon]

The TV's abilities to decode audio aren't affecting the current setup as far as I can tell. Yes, the TV can decode AC3 and it can't decode DTS. However, the EDID being reported back to the audio driver does in fact get picked up as supporting DTS as well as AC3 - this can be seen in the details of the HDMI Audio device in Windows. I don't know if it's something the audio device is adding or if it's something the DVDO Edge is adding. There are a few other things listed there too, but unfortunately I can't remember what they are right now and at the moment, connecting to that system with Remote Desktop disables the audio devices and control panel details so I can't see them. But again, everything I've read about AC3Filter say it overrides all that information - otherwise it would not be possible to use SPDIF over toslink for DTS for anyone either.

We're in agreement, which is why the extenders are such a huge deal in removing any such headaches. I already briefly alluded to the hassle of getting HDMI audio on this system at all. In fact if you only install the drivers available on Zotac's web site you will not have audio over HDMI at all. And I didn't find anything on their site to indicate that as a problem nor anything about seeking out the missing pieces.

However, it would have been nice, though understandably an enormous and difficult PITA given the state of the underlying system, for Sage to have built-in all the options to describe what you want to do with your source audio, which, IMO, is not something that should have to be configured in Windows or third-party codec/decoders. If the system is going to pass everything through, it would be ideal to have options within Sage to deal with all the current surround modes, telling it whether or not you want down-mix, passthrough, re-formatted multi-channel, etc. There's no way for the app, or the OS/other decoders to know the capabilities of digital connections that don't have a return channel. Similar to the audio setup in the extenders and a number of other products.

I've been running SageTV as my only interface to broadcast/cable TV since late 2004 and up until the end of 2008 I was doing it with the client features built into the server app. Since then with an HD200, over the past two weeks with the addition of an HD300 and now adding a stand-alone PC-client to the mix as well. If I start using Placeshifter I'll have covered the whole current range (I'm not going back to try out an MVP nor HD100)

[TwistedMelon]

Originally Posted by jorton

EDIT: look for "videoframe/dca_audio_decoder_filter=" and set to be the same as "videoframe/audio_decoder_filter=" depending on if you use ffdshow Audio Decoder or ac3filter Audio Decoder.

I never get passthrough of DTS on my MKV's unless I set this with AC3filter or FFShow Audio Decoder. DCA is how Sagetv reports DTS in the file info's.

This is precisely the point I was talking about when I mentioned "feature complete" - the UI is missing some items that would make it easier to set up or at least less confusing. Why on earth is there an MPEG audio decoding filter selection in the UI, along with one for HD audio, but not one for DTS?

I'd say that without this forum and/or guides elsewhere on the net, it would be next to impossible to set up a fully functional PC client for even the typical enthusiast, let alone the average consumer.

[TwistedMelon]

Thanks again for the help and advise guys. jorton, if you hadn't mentioned that property I don't think I would have ever found it - I just wouldn't have thought it existed in the first place.

Ok, I had to make the change in the properties file and then I still had to change something else in AC3Filter.

On the site missing remote as part of a SageTV 7 setup article they mentioned turning on the "Padded DTS" option under the heading SPDIF/DTS. Seen here:
http://www.missingremote.com/guide/i...ng-sagetv-v7-0

That doesn't work on my system. I have to select the "auto" option - though I haven't tried the SPDIF Wrapped option.

Now DTS is passing through, but I've found one rip so far that causes severe audio stuttering. Tested the same file on HD200 and audio drops every now and then, but it's useable. About to investigate why by looking more closely at the file (bitrate and such).

That said, does anyone know if there has ever been a situation in which the Gemstone plugin on the server or client has adversely affected the ability to stream/decode/display files over the network? I'm testing with Sage's network file browser at the moment, not imported files.

EDIT: So far the only thing I can see is that when I last ran this file through MKVToolnix it saved it back out with header stripping. Pretty sure this is what's casing the issue. Time to re-mux and re-test.

[TwistedMelon]

Ok, the issue is not DTS-specific related nor the header stripping/compression. It seems to be bit rate and encoding complexity related. I've now duplicated the choppy audio and choppy video with AC3 tracks that have less bit rate but higher complexity.

Examples:

11.5 Mbit/s 1920x800, AVC level 4.1 w/ 5 ref frames - DTS audio
10Mbit/s 1920x800 AVC level 5.1 w/ 8 ref frames - AC3 or DTS audio


Then one that seems to play properly:
10.5Mbit/s 1920x800, AVC level 4.1 w/5 ref frames - DTS audio

As mentioned, I'm using the built-in Microsoft renderer and decoders. Should I switch over to something else more "ideal" for this stuff? Any suggestions?

[Fuzzy]

to be honest, I've never had a problem setting this up, in fact, it pretty much works out of the box. The problem you are having, like most directshow related problems, is likely something to do with filter mess. The reason sage doesn't have a DTS option in the UI, is because AC3Filter (which is installed with sage) handles DTS perfectly fine. You most likely have some other filter with a higher merit than ac3filter, and it is taking it over, and not handling it properly. You can enable AC3Filter's tray icon in it's configuration, and this will tell you if it is in use. If it is, then you will see the status of what is going on when you bring up the UI from the tray icon. If you turn on AC3Filter's tray icon, and it doesn't show up in the tray while playing, than something else is getting used.

[TwistedMelon]

Thanks for the info. That's also the impression I was under, but I haven't been able to get the tray icon to show up. However, when I disable AC3Filter or adjust its settings, I can alter the audio output - make it stop working for instance.

So while the tray icon doesn't show up, all other signs indicate it's being used.

When I installed SageTV AC3Filter did get installed, but it most definitely wasn't producing any sound at all until I went in and set everything to passthrough. The thing is that I did update AC3Filter prior to doing that. I can back out the newer version and go back to the one SageTV has installed of course.

[Fuzzy]

any version of ac3filter should work (they really haven't made and significant changes for many years on it).

Do you have the tray icon setting enabled? Run AC3Config, and it should be on the System tab, called Show Tray Icon. Another thing to try, is to download graphstudio, and have it render out one of your recordings. This will tell you what filters directshow is trying to use to playback that file. You will, in the end, have much better success if you have get it to work with your decoders and such through graphstudio, and then set sage to 'default' for just about everything.

[TwistedMelon]

So small update.... This does still seem like a DTS issue specifically. I was incorrect about the problem happening with AC3 files. I mistakenly thought the files I tested were AC3 because Gemstone identified them as such. It turns out it was identifying the first audio track but it was playing the second, which was DTS...

That said, I have only ever installed ffdshow and AC3Filter on this system - ffdshow uninstalled before trying to fix this issue. Now AC3Filter uninstalled.

Sage's own copy would not run after the uninstall so I just reinstalled Sage to replace it. Still can't get the tray icon to show up and it definitely started without DTS set to passthrough. Set that all up the same way (this older version doesn't have quite all the option) and.... It's working where the newer version (2.5b) was not.

Couple more things to test out before I report back.

[TwistedMelon]

Sage's included copy of AC3Filter seemed to work well enough, I still have a few files to test it with tomorrow.

Just to confirm newer versions may be the issue, I then installed AC3Filter 2.4a from this past summer. Like 2.5b it had the same choppy output on many DTS tracks. And on one movie the choppiness further affected the video as well (same as on 2.5).

One very curious thing is that with 2.4 the tray icon appears when Sage is up. I'll probably try out a few more versions tomorrow. Kind of ironic that there's so much work involved simply to pass through the audio. In other words, to prevent the computer/software from having to do anything at all to the signal.

[Fuzzy]

Originally Posted by TwistedMelon

Sage's included copy of AC3Filter seemed to work well enough, I still have a few files to test it with tomorrow.

Just to confirm newer versions may be the issue, I then installed AC3Filter 2.4a from this past summer. Like 2.5b it had the same choppy output on many DTS tracks. And on one movie the choppiness further affected the video as well (same as on 2.5).

One very curious thing is that with 2.4 the tray icon appears when Sage is up. I'll probably try out a few more versions tomorrow. Kind of ironic that there's so much work involved simply to pass through the audio. In other words, to prevent the computer/software from having to do anything at all to the signal.

Like i eluded to earlier, this is a rare case. I've never had to do anything more than set AC3Filter to SPDIF. Of course, since then I've moved to real HDMI audio, and I now send everything out uncompressed, which is even easier.

[TwistedMelon]

A new pre-pro is going to have to wait a bit of time on this end. It also means I'm going to have to somewhat modify the space behind my custom cabinet, because while I allowed for a very large processor footprint, all the new products seem to be even bigger with connectors in sub-optimal places.

Though I suppose if I could override the EDID seen by the system to tell it that my processor supports AC3, DTS and 7.1 channels, I might be able to obviate some of the need for AC3Filter's SPDIF overrides.

Considering that AC3Filter's only job in my case is to force route the audio untouched, it's pretty troublesome that different versions are causing problems and distorting the audio stream.

Is everyone else using the AC3Filter that ships with the Sage installer?

[TwistedMelon]

Seeing as I have to do a new install on this client system in a couple of weeks, I'm setting aside the SageTV and AC3Filter investigations for now. Things seem to work without installing newer updates.

What I'm going to concentrate on instead. is trying to figure out why the hardware/drivers themselves aren't producing the results I expect as far as audio goes. Such as the ATI/AMD drivers not detecting that my HDMI device supports audio at all. Such as having to install a RealTek driver over top of the ATI to get the HDMI audio device working at all - this shouldn't be necessary.

The HDMI audio device after current AMD/ATI driver install reports DTS, AC3 and PCM, but ZERO channels.

I'll be in a much better position once all the low level issues are sorted - I'm confident that the higher level software is already working well at this point.

[TwistedMelon]

Related question...

Is Sage Client with the default AC3Filter setup supposed to be able to play MP3 audio muxed in an MKV? AAC and FLAC seem fine but MP3 just produces no sound.

[Fuzzy]

I don't believe it supports mp3. I think it supports decoding (or even bitsteraming) MPEG Audio, which is most likely MPEG-2 Layer 2. mp3, however, should be handled just fine with the sage MPEG decoder.

[TwistedMelon]

Sorry, I just realized I worded the question awkwardly. I didn't mean to ask if AC3Filter will handle it, but with an otherwise default SageTV Client install, using the MS decoders for video, is MP3 audio in MKV supposed to work?