problem decoding DTS-ES to stereo

[capridik]

Hi there,

I've an audio track here in DTS-ES 6.1 channel sound that I want to downmix to stereo.
I've installed ArcSoft decoder which did a good job for the 5.1 inputs so far but the output of
eac3to -down16 -down2
is crap. It contains a hissing and whistling over the whole track.
I already tried
eac3to -down16 -down6
but got the same result.
Forcing eac3to to use libav results in clean audio but compared to playing the DTS track directly it seems to lack the very low frequencies - not unexpected as eac3to writes "The libav DTS decoder doesn't decode the back channels."

Mediainfo on the file:
Channel(s) : 7 channels / 6 channels
Channel positions : Front: L C R, Side: L R, Back: C, LFE / Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Bit depth : 16 bits

Any ideas how to correctly downmix everything to stereo?

Thanks, capridik

[Midzuki]

Hi there to you too

IIWY, I would try the following (OK, it IS complicated and convoluted, but it may work):

install (register) LAV Audio, copy the file DTSdecoderdll.dll to its folder, build an appropriate .GRF file in GraphEdit (or GraphStudio), write a suitable Avisynth script, convert this to a 6.1 (or an already downmixed stereo) .WAV through wavi.exe.

HTH ^.^ ;

[capridik]

Originally Posted by Midzuki

IIWY, I would try the following (OK, it IS complicated and convoluted, but it may work):

install (register) LAV Audio, copy the file DTSdecoderdll.dll to its folder, build an appropriate .GRF file in GraphEdit (or GraphStudio), write a suitable Avisynth script, convert this to a 6.1 (or an already downmixed stereo) .WAV through wavi.exe.

Hm, quite some new stuff to chew.

I can't see what benefit copying DTSdecoderdll.dll gives me. Also I didn't manage to use the Avisynth script as input to wavi (wavi Audio.avs Audio.wav resulted in
Error: Could not find PCM audio track in Audio.avs.).
And I also don't know what you had in mind of downmixing the stuff.

But what I did and what pretty much works is building a graph
DTS -> LAV Audio Decoder - > ffdshow Audio Processor (using the mixer matrix do downmix to stereo)
and the avs looks like this

DirectShowSource("Audio.grf", video=false)
SoundOut(output="WAV", filename="Audio.wav")

So thank you for pointing me to GraphEdit (a program I started a few times already but also closed right away) together with Avisynth. I'm nevertheless curious about details on the dll and wavi (and any other, maybe less complicated way of getting to my result).

cu, capridik

[Midzuki]

Originally Posted by capridik

Hm, quite some new stuff to chew.

Actually not so new. Doom9's forum is supposed to be visited once a week at least, not only when you meet some audio-/video-related problem

I can't see what benefit copying DTSdecoderdll.dll gives me.

LAV Audio can hook directly onto ArcSoft's DTS decoder, whereas eac3to requires ASAudioHD.ax, checkactivate.dll, etc etc etc.

Also I didn't manage to use the Avisynth script as input to wavi (wavi Audio.avs Audio.wav resulted in
Error: Could not find PCM audio track in Audio.avs.).

Hmmm, I will have to verify if the same thing happens over here.

But what I did and what pretty much works is building a graph
DTS -> LAV Audio Decoder - > ffdshow Audio Processor (using the mixer matrix do downmix to stereo)
and the avs looks like this

DirectShowSource("Audio.grf", video=false)
SoundOut(output="WAV", filename="Audio.wav")

So thank you for pointing me to GraphEdit (a program I started a few times already but also closed right away) together with Avisynth.

You're welcome.

[Midzuki]

Originally Posted by capridik

Also I didn't manage to use the Avisynth script as input to wavi (wavi Audio.avs Audio.wav resulted in
Error: Could not find PCM audio track in Audio.avs.).

Now I can confirm that, wavi.exe apparently doesn't like DirectShowSource on .GRF files

As for avs2pipe(mod).exe:

avs2pipemod [error]: avs files return value is not a clip.

[Midzuki]

Hmmm, I've run some more tests with two different graphs (one includes ffdshow audio processor, whereas the other does not), and several AVS files (with and without an audiodubbed BlankClip). wavi.exe likes Audiodub() without ffdshow, but detects 6 channels instead of seven. As for VirtualDub and MPC, they show 7 channels with ffdshow, but only 6 channels without ffdshow.

----------------
EDIT

After UN-registering Gabest's AC3/DTS Source Filter and by using LAV Splitter, now wavi.exe does accept the following graph:

FileSource -> LAV Splitter -> LAV Audio

=>wavi 6p1-DTS.avs

[dts @ 00d42060] max_analyze_duration 5000000 reached at 5002667
[dts @ 00d42060] Estimating duration from bitrate, this may be inaccurate
Found PCM audio: 7 channels, 48000 Hz, 24 bits, 27.259396 seconds.

[tebasuna51]

Originally Posted by capridik

...
I've installed ArcSoft decoder which did a good job for the 5.1 inputs so far but the output of
eac3to -down16 -down2
is crap. It contains a hissing and whistling over the whole track.

Is a know ArcSoft decoder bug with 6.1, you need the 1.1.0.0 old version.

Forcing eac3to to use libav results in clean audio but compared to playing the DTS track directly it seems to lack the very low frequencies - not unexpected as eac3to writes "The libav DTS decoder doesn't decode the back channels."

libav work fine and to downmix to stereo the back channel is not needed.
I can't understand the lack at low frequencies, please put a sample.

[capridik]

Originally Posted by Midzuki

Hmmm, I've run some more tests with two different graphs ...

Thank you Midzuki for your research! I haven't available the strange DTS file anymore (I'm doing recoding for saving space and delete it afterwards if all is fine).
But I definitely appreciate your work and keep this thread bookmarked for reference.

[capridik]

Originally Posted by tebasuna51

Is a know ArcSoft decoder bug with 6.1, you need the 1.1.0.0 old version.

libav work fine and to downmix to stereo the back channel is not needed.
I can't understand the lack at low frequencies, please put a sample.

Ah, there we go. I'll have a look for the old version of the decoder. Are there any known drawbacks for not using the later versions?

Sorry, I can't provide samples since I have that file anymore (I'm doing recoding for saving space and delete it afterwards if all is fine). It wasn't a scientific inspection I conducted and maybe I was wrong. On the other hand listening to the back channel alone there was quite some effects happeing.

[Midzuki]

Originally Posted by capridik

Ah, there we go. I'll have a look for the old version of the decoder. Are there any known drawbacks for not using the later versions?

http://forum.doom9.org/showthread.ph...78#post1508578

Welcome to the ArcSoft hell

[nevcairiel]

Originally Posted by tebasuna51

Is a know ArcSoft decoder bug with 6.1, you need the 1.1.0.0 old version.

Actually, its a problem in eac3to. The only thing absolutely broken in the ArcSoft decoder is 6.0, 6.1 works fine.