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Topic: Dolby jumps on the upsampling bandwagon (Read 6508 times) previous topic - next topic

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  • julf
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Dolby jumps on the upsampling bandwagon
Reply #25
As long as the phase changes are equally applied to both channels, IME the ear's tolerance for phase distortion is *huge* - over a thousand degrees > 2 Khz. I understand that the ear lacks the ability to meaningfully detect over all phase shift above about 1 KHz.


That is very interesting - do you have any references?

Dolby jumps on the upsampling bandwagon
Reply #26
As long as the phase changes are equally applied to both channels, IME the ear's tolerance for phase distortion is *huge* - over a thousand degrees > 2 Khz. I understand that the ear lacks the ability to meaningfully detect over all phase shift above about 1 KHz.


That is very interesting - do you have any references?


Aduioholics page on the audibliity of phase

Personal experience:

ABX Audio Chamber of Horrors

  • julf
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Dolby jumps on the upsampling bandwagon
Reply #27

  • andy o
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Dolby jumps on the upsampling bandwagon
Reply #28
I think there's a simpler explanation. Dolby is just getting desperate cause no one is using their TrueHD codec. Their high point was in 2008 with about the same number of titles as DTS-HD MA (about 42% of all lossless blu-rays), but then it steeply declined. In 2009, 33% vs. 58% of DTS. 2010, 11%vs. 82%, and in 2011, 10% vs. 83% (blu-raystats.com). And even then, mostly the releases that consistently use their codec are japanese animation which sell far less than big studio blockbusters.

  • xslig
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Dolby jumps on the upsampling bandwagon
Reply #29
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Dolby is just getting desperate cause no one is using their TrueHD codec.


IMO, this is the cause of any problems Dolby has and will have (and especially more so since the "content providers" have made it abundantly clear that Blu-ray will be the last readily available physical consumer format ["To the cloud!", :P])

I would have to say that Dolby management is just plain incompetent (I'm no DTS fanboy, I actually prefer Dolby Digital and TrueHD to DTS lossy and DTS-HD MA.)

- Siding with Microsoft in the HD-DVD vs. BD format war (15GB/layer vs. 25GB/layer, no brainer IMO)
- Pushing TrueHD when seamless branching wasn't working.
- Releasing the TrueHD encoder for MacOS only when most BD creation tools are for Windows.

But of course the main reason it isn't used:

- Ffmpeg reverse engineered all of your codecs

DTS-HD MA is basically just another form of DRM since there is hardly any documentaion on it, and no free decoder available. (The "content providers" all know this, but won't admit it.)


I predict that Dolby will be largely irrelevant in the coming decade (only necessary for legacy issues)

  • andy o
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Dolby jumps on the upsampling bandwagon
Reply #30
They have stuff that does work, but don't put much effort into promoting it. I like Dolby Headphone, for instance, but its obvious implementation on mobile devices is almost non-existent. I can see getting 5.1 files decoded on an Android phone and played through DH. They have the so-called Dolby Mobile thing, but it's nowhere to be seen except for some odd phones that nobody has.

  • Buckchoi
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Dolby jumps on the upsampling bandwagon
Reply #31
Nokia use DH on their recent Symbian devices.

  • andy o
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Dolby jumps on the upsampling bandwagon
Reply #32
I only know one person that had a Symbian phone, and then he got an iPhone. Now I know no one who does.

I don't know what prevents Dolby of coming up with an Android app like there are DSP apps for it. Too computationally expensive? I know there are players that decode Dolby Digital. With the wide range of CPU power on Android devices, I don't think it would be too hard for them to offer it on many devices.
  • Last Edit: 24 May, 2012, 02:02:15 AM by andy o

  • 2Bdecided
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  • Developer
Dolby jumps on the upsampling bandwagon
Reply #33
I predict that Dolby will be largely irrelevant in the coming decade (only necessary for legacy issues)
You won't find many DTS TV broadcasts

Even AAC TV broadcasts are transcoded to AC-3 for digital output. Both have Dolby brand names

Dolby has a fine revenue stream there for years to come.

Cheers,
David.

  • 2Bdecided
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  • Developer
Dolby jumps on the upsampling bandwagon
Reply #34
As long as the phase changes are equally applied to both channels, IME the ear's tolerance for phase distortion is *huge* - over a thousand degrees > 2 Khz. I understand that the ear lacks the ability to meaningfully detect over all phase shift above about 1 KHz.
Careful. Isn't 1000 degrees at 2kHz is about 1.3ms? Honestly, if you take an impulse, delay the energy about 2kHz by 1ms, you will hear a difference! It goes splat instead of click.

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Brick wall filters @ 16 Khz are generally sonically transparent or very close to it.
close to it - plenty of people on HA (and it predecessors) have ABXed it. That's why lame puts is LPF around 19kHz for the "transparent" presets.

Of course the difference in sound is exactly what you'd expect (a loss of very high frequencies / "brightness") - nothing like the kind of thing reported when people object to 44.k1Hz sampling with a sinc filter.

Cheers,
David.

Dolby jumps on the upsampling bandwagon
Reply #35

As long as the phase changes are equally applied to both channels, IME the ear's tolerance for phase distortion is *huge* - over a thousand degrees > 2 Khz. I understand that the ear lacks the ability to meaningfully detect over all phase shift above about 1 KHz.


Careful. Isn't 1000 degrees at 2kHz is about 1.3ms? Honestly, if you take an impulse, delay the energy about 2kHz by 1ms, you will hear a difference! It goes splat instead of click.


I was thinking about typical real world musical program material. I agree and have experienced what happens to unit impulses with that kind of all-pass filtering. I would say "sproing" rather than "splat", but YMMV! ;-)

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Quote

Brick wall filters @ 16 Khz are generally sonically transparent or very close to it.

close to it - plenty of people on HA (and it predecessors) have ABXed it. That's why lame puts is LPF around 19kHz for the "transparent" presets.


Again I agree and have experienced it, but again my context is typical music. You just don't find a lot of periodic naked unit impulses in music.

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Of course the difference in sound is exactly what you'd expect (a loss of very high frequencies / "brightness") - nothing like the kind of thing reported when people object to 44.k1Hz sampling with a sinc filter.


Point being that the Dolby slide that goes on about "a cleaner, smoother sound field"  and "a clearer audio image" is the usual audiophile-speak that can mean anything but often means nothing.