Unable to have AC3 audio while an HE-AAC decoder is enabled.

[smiffypr]

I'm successfully running AC3Filter togather with Monogram HE-AAC decoder, but I'v never had any luck combining ffdshow with other decoders. There are other available decoders that does a equally or better job than ffdshow, what do you need it for? Have you tried HD Pack or SD Pack from http://www.dvbsupport.net/ ?

The HD Pack doesn't seem to include anything I haven't already got, and they want money for it.
I've downloaded mm_aac_dec_0.9.6.0_bin, but that just gives me an ax file, with no instructions on what to do with it.
But anyway, Sub has said he can use arcsoft for HE-AAC and ffdshow for AC3, so I need to work out why I can't do the same.

[Reddwarf]

The HD Pack doesn't seem to include anything I haven't already got, and they want money for it.
I've downloaded mm_aac_dec_0.9.6.0_bin, but that just gives me an ax file, with no instructions on what to do with it.
But anyway, Sub has said he can use arcsoft for HE-AAC and ffdshow for AC3, so I need to work out why I can't do the same.

A set of decoders working on one installation does not nessesarily mean that it will work on another one. Have you tried Monogran AAC decoder (for HE-AAC)?

[smiffypr]

A set of decoders working on one installation does not nessesarily mean that it will work on another one. Have you tried Monogran AAC decoder (for HE-AAC)?

I have now (I had to remind myself what to do with the ax file), and it makes no difference to the problem.

[Reddwarf]

I have now (I had to remind myself what to do with the ax file), and it makes no difference to the problem.

That's strange. It seems to me that there's something fu%¤ing up your decoders, I'd try to uninstall ALL decoders and install only the nessesary one by one.

[smiffypr]

That would be a lot of work, and I don't understand how it would help to un-install decoders that are not being used by NPVR.
What I don't understand is how NPVR selects and drops decoders. (I know that is not the correct terminology.)
For example, if I have ffdshow selected for AC-3 and Arcsoft for HE-AAC, I start to watch something which has both audio tracks, when I select the AC3 track, the ffdshow tray icon appears and hovering the pointer over it shows the input to the filter being AC3. But when I change to the HE-AAC track, the ffdshow tray icon stays there, and keeps showing that it has an ac3 input, only when I stop watching does it disappear.
It just so happens that AC3Filter also has a tray icon which appears when it is in use, and its behaviour is not quite the same. It appears as soon as I start watching, that is, before I select the AC3 track, but does say "SPDIF status : no data". When I change to the AC3 track, that changes to "SPDIF status : SPDIF passthrough", but when I change the track back to HE-AAC again, that status stays at SPDIF passthrough. That suggests to me that npvr is not "dropping" a decoder when I would expect it to. If I had an HE-AAC decoder which showed a tray icon when it is working that would give me a better idea of what is going on when I switch audio streams.
If anyone can explain how npvr is supposed to do this, it would be a help to me.

[sub]

For example, if I have ffdshow selected for AC-3 and Arcsoft for HE-AAC, I start to watch something which has both audio tracks, when I select the AC3 track, the ffdshow tray icon appears and hovering the pointer over it shows the input to the filter being AC3. But when I change to the HE-AAC track, the ffdshow tray icon stays there, and keeps showing that it has an ac3 input, only when I stop watching does it disappear.

NPVR adds all the enabled decoders when playback starts. It cant add them when you switch audio streams (since that would require stopping and rebuilding the graph). Instead, it simply controls the demultiplexer filter to tell it which decoders will get data, and which will get none.

It just so happens that AC3Filter also has a tray icon which appears when it is in use, and its behaviour is not quite the same. It appears as soon as I start watching, that is, before I select the AC3 track, but does say "SPDIF status : no data". When I change to the AC3 track, that changes to "SPDIF status : SPDIF passthrough", but when I change the track back to HE-AAC again, that status stays at SPDIF passthrough. That suggests to me that npvr is not "dropping" a decoder when I would expect it to. If I had an HE-AAC decoder which showed a tray icon when it is working that would give me a better idea of what is going on when I switch audio streams.

Unfortunately I dont have any SPDIF setup here, so this isnt something I can really help you with. From NPVR's perspective, this is something hidden inside the decoders, and it doesnt really know anything about SPDIF.

[Reddwarf]

@smiffypr: Do you have an amplifier connected to a SPDIF output?

[smiffypr]

I think that does explain what is going on.
With SPDIF passthrough, there can only be one stream of data which successfully gets to the output, so when the AC3Filter is in control of the actual output from the motherboard nothing else can over-ride that.
If I use PowerDVD to replay a recording with two audio tracks, its using two parts of the same decoder, so it doesn't run into this issue.
The easiest solution for me would be to find one filter which will work with HE-AAC and AC3. The powerDVD decoder can obviously do both, but won't work (for me) with NPVR (it doesn't show up as an option for HE-AAC, and doesn't work for AC3).

[smiffypr]

Yes. That is the only audio output from the pc. The good thing (from a diagnosis point of view) is that the amplifier displays what it is receiving, e.g. Dolby PL or Dolby D.

[Reddwarf]

Yes. That is the only audio output from the pc. The good thing (from a diagnosis point of view) is that the amplifier displays what it is receiving, e.g. Dolby PL or Dolby D.

Hmmm, the MPA Decoder Filter has some settings for AAC but (at least on my computers) the Settings window is too small to access them... You could try tricking npvr into using it just to see if it works.