Wrong 7.1.4 output in Cavernize

[VoidXH]

DD+ Atmos channel tests look like they use the asymmetric renderer. Add tests so this doesn't happen again.

[VoidXH]

Fixed in be4d984 and released.

[kaedewang]

TRR is OK.
And how about these, are they correct?

[kaedewang]

These unwanted output seems only to happen after pink noise.

[VoidXH]

Sadly, this is proven a compression issue. Please use the version from a Dolby Atmos Demo Disc, that has no such issues with triple the bitrate:

[kaedewang]

EN? But I try to decode the same file by DRP. There is no such issue.
And there is only thd track(no EAC3) from my Demo Disc.

[VoidXH]

That can't be, all my demo discs have DD+ 7.1 tracks next to the THD. This distortion is there on the JOC level, the mixer is fine.

[VoidXH]

But they do not. They have all AC3 core inside, AC3 core is inside EAC3 Atmos tracks.

That's one of the few, here's every track from a demo content (example file):

• TrueHD 7.1 + Atmos
• DD+ 7.1 + Atmos
  • Substream 0: DD 5.1 compatibility track
  • Substream 1: Surrounds and rears overriding the old surrounds, resulting in 7.1
• Mandatory DD 5.1 companion track telling you to use Atmos

The correct version of this test has a 7.1 DD+ track originally:

[VoidXH]

Did you check DRP?

I don't have it.

[VoidXH]

It already happens in ADM or base layer (compare base layer decoding to ffmpeg)? Or you need 3rd stage (render)?

The channel decoding gives the exact same results as FFmpeg, and the renderer is well tested since the bug fix, it has no distortion. Object placements are correct, the issue is in the JOC decoder/documentation.

[VoidXH]

There was a -6 dB FBW gain which was removed today, that's the gain difference. The extra noise you are seeing in the old version is the result of the asymmetric renderer (which is not using balanced-based rendering and always adds sound to neighboring channels) that was triggered by the wrong channel layout, that was also fixed.

It's pretty strange that issues only appear when something was already played, looks like the JOC matrices didn't reset to zero. That might have been because I missed part of the standard, but that needs some debugging.

[VoidXH]

I was wrong, issues were in the AC-3 decoding, not in the JOC. For some reason, it has this huge crosstalk, these are the decoded raw FBW channels. The JOC threw away anything before the first sample for each channel, that's why you couldn't see the issues there.

[VoidXH]

Fixed in 5a2fe5d and released.

[VoidXH]

That wasn't anything related to DRC, I never even implemented DRC. The LFE is contained at wrong gains for E-AC-3, and FFmpeg actually causes clipping for this demo.

[VoidXH]

So Dolby did a mistake?? Same bug on Blu-ray?

It's probably an FFmpeg bug. I don't see a clause for this in the spec.

Well, it is not like there are no bugs there too, just 2 days ago

That's SPX, Cavern doesn't even support it as it's unused.

[kaedewang]

It's cool. Volume seems to be normal, too.
wav file is too large. I put the snapshot by DRP.

[VoidXH]

Is this the DRP result? Because it has clipping LFE like FFmpeg.

[kaedewang]

Because it has clipping LFE like FFmpeg

Yes，LFE of dolby-test-tones_7_1_4 is louder than other version.
I try another version called 7.1.4. There is no clipping.

[kaedewang]

@ValZapod Please try this.
https://gist.github.com/Plazik/e950267cc580bcde371ea7879aaa3d5d

[VoidXH]

I try another version called 7.1.4. There is no clipping.

Is that the Atmos demo disc version?

[kaedewang]

Is that the Atmos demo disc version?

I don't know. I download single m2ts from web.

[kaedewang]

$ md5sum.exe 7.1.4.m2ts
3894800dd2d3c83edd0eb8911d851094 *7.1.4.m2ts

[kaedewang]

EE362F6275170762D9A74C4C8C8A9F53

I have this version. But this version only has thd track.

[VoidXH]

Thank you for this file, it has been fixed too in the latest release.

[VoidXH]

Then why does Audition does not see it?

It will render at the correct channels. The file order doesn't matter if the metadata contains which channel is which, and Cavernize exports do. It's also the only correct order if you don't contain metadata, it will also work without the WAVEFORMATEX header.

[VoidXH]

None. Audition displays the file's channel order, and renders all of them at the correct channels. DRP exports with the correct channel names.

[VoidXH]

Then they don't support the WAV channel mask correctly. It's always backs before sides for WAV. Dune has it even worse, they think it's L R C LS LR RR RS LFE...

[kaedewang]

@VoidXH Could you please add an option to swap ch5/6 and ch7/8，it will be very useful for me.

[VoidXH]

So that is still a bug, you are supposed to only remove half of it (?)...

More than likely there should be a -3 dB decrease only. There are no gain values in the OAMD/JOC (well, there are, they just say 0 dB), so I think I should use the ones from the (E-)AC-3, I just don't know which one, because program level is absolute and dowmix level is always -3, even when it shouldn't be. What is the result of the reference player for overwatch? Is it also clipping?