Insane Bitrates On Both Pirates Films!!

[Deciazulado]

Peter, isn't the EX 6th channel in DolbyDigital prints matrixed? (yes I know not the same as the 24 bit Master having 6 channels discrete before Dolby encoding. but maybe the 6th channel is matrixed into the LPCM stereo surrounds.) We need a Film Mixer over here! Is there a Film Mixer in the house?

[NutsAboutPS3]

Originally Posted by phloyd

However... if there is a buffer that can store up video that is then 'released' at a huge bitrate, the 48Mbps need not apply.

Yes, the whole point of a buffer is that there can be a difference between the input and output rates. The amount of data contained in the buffer will shrink or expand depending on which rate is higher. A higher output rate can only be sustained for so long before the buffer is emptied. The Blu-ray spec will state what buffer size is required, and what input rate the disc reading hardware must be capable of sustaining. I would expect there to also be some constraints on the output rate in the specification. Encoding software can be programmed to allow the output rate to be transiently higher than the sustainable input rate, knowing how much latitude it has before the buffer is emptied.

[Rio]

Right. BD spec allows to have maximum 40Mbps input rate for video ES only, 48Mbps input rate for combined all of them (this is TS rate, not the combination of bit rate of all ESs). In the POTC case, due to the 24bit audio and additional audio tracks being there, the video peak rate (actually, this is maximum input rate) must be less than 40Mbps, although instantaneous bit rate that PS3 shows can surpass much further due to the fairly big AVC decoding buffer.

[donricouga]

http://en.wikipedia.org/wiki/Blu-ray

Raw Data Transfer max rate is 53.95 Mbits/s
Audio+Video maxes out at 48.0 Mbit/s
Video has a max of 40.0 Mbit/s

[Tekman]

This from pioneer's site
http://www.pioneerelectronics.com/pn...136015,00.html


And since we're making comparisons, let's talk about bit rate. With video that's been compressed, higher bit rates help eliminate artifacts and "noise" in moving images. So the action is cleaner, crisper and more realistic. Standard DVDs deliver a bit rate of up to 10 Mbps. The HDTV broadcasts you have come to love on your flat panel screen can reach up to an impressive 19 Mbps.
Blu-ray Discs positively scream at up to 48 Mbps! That's nearly five times the bit rate of the DVDs you're used to, and it greatly exceeds the bit rate of broadcast HDTV. No matter what you're watching, it will probably look better on a Blu-ray Disc.

[Tekman]

http://au.playstation.com/ps3/hw/bluray.jhtml

Maximum Bit Rate
With the overwhelming computational power of its Cell Broadband Engine processor, PLAYSTATION®3 is capable of playing back with ease content from BD at a bit rate of multiplex 48Mbps, the maximum bit rate defined in BD standards

[McBain]

http://www.emedialive.com/articles/r...leid=11397#iif

[phloyd]

I believe from my 'probings' that the BD TS stream is hard limited to 48 Mbps - the time code slots max out at that rate.

Of course, it is possible to read the data faster than 'real time', resulting in higher rates off the disc - but eventually you will get back to the bitrate on the disc maxes out at 48 Mbps.

[Sir Terrence]

Originally Posted by PeterTHX

Well, I appreciate that the movies are 24 bit but they should have been 6.1/7.1 PCM since the movies are EX.

So the lowly Dolby track at 640kbps represents the imaging of the original sound mix

Peter, there is no way to do this except to go back and create a another channel in the studio. This is not cheap. EX is a electrical encode/decode process associated with Dts(with ES) and DD(with EX). Because these data streams are constructed differently after encoding, the process can't be ported over to a PCM stream. This is why I kept my circlesurround decoder even though I have ES and EX built into my receiver. My circle surround processor allows me to create a EX channel with any digital or analog source.

[PeterTHX]

Originally Posted by Sir Terrence

Peter, there is no way to do this except to go back and create a another channel in the studio. This is not cheap. EX is a electrical encode/decode process associated with Dts(with ES) and DD(with EX). Because these data streams are constructed differently after encoding, the process can't be ported over to a PCM stream. This is why I kept my circlesurround decoder even though I have ES and EX built into my receiver. My circle surround processor allows me to create a EX channel with any digital or analog source.

The other channel is already there in the master. When the printmaster is made then that previously discrete channel is matrixed in.

If lowly Lionsgate can do it with "The Descent" and "Crank" then so can Disney.

Reason I'm unhappy is that thru PCM/HDMI I can't process the signal and get that EX channel back. If I play it with PCM I'm stuck with 5.1, if I play it in Dolby I get 7.1 EX...the original mix.

It's like OAR. Sure you can watch a Super35 film in 16x9 and not miss anything , but it's still not originally the way it was meant to be seen.

[Sir Terrence]

Originally Posted by PeterTHX

The other channel is already there in the master. When the printmaster is made then that previously discrete channel is matrixed in.

If lowly Lionsgate can do it with "The Descent" and "Crank" then so can Disney.

Reason I'm unhappy is that thru PCM/HDMI I can't process the signal and get that EX channel back. If I play it with PCM I'm stuck with 5.1, if I play it in Dolby I get 7.1 EX...the original mix.

It's like OAR. Sure you can watch a Super35 film in 16x9 and not miss anything , but it's still not originally the way it was meant to be seen.

I am aware how it is done, that is not the issue. You outlined the reason I tried to state better than I did.

I'm unhappy is that thru PCM/HDMI I can't process the signal and get that EX channel back. If I play it with PCM I'm stuck with 5.1, if I play it in Dolby I get 7.1 EX

This is why its a waste to include a EX channel in the PCM mix. Its not decodeable by internal EX decoders. You are right though, they could have just done a discrete PCM channel. Quite a few post houses are equipt to create and monitor a true 6.1 system.

By the way, Dolby EX NEVER yields a 7.1 soundtrack. The true nomenclature for EX is 5.1+1, as it is a enhancement to the surrounds that rides within the surround signals. Once you combine the discrete 6 channel into the matrix, it can never be discretely recovered. The matrix yields a single channel, not two. That single channel comes through two speakers as a mono signal, so you can never get anything more than a matrixed single channel, not 7.1

[PeterTHX]

By the way, Dolby EX NEVER yields a 7.1 soundtrack. The true nomenclature for EX is 5.1+1, as it is a enhancement to the surrounds that rides within the surround signals. Once you combine the discrete 6 channel into the matrix, it can never be discretely recovered. The matrix yields a single channel, not two. That single channel comes through two speakers as a mono signal, so you can never get anything more than a matrixed single channel, not 7.1

I know this, I have a 7.1 setup so my receiver duplicates the rear surround channel between the back left and back right.

I know how all this works, all I'm saying is that they should have done what Lionsgate did with the titles I mentioned.

I'll have to upgrade my receiver to something like the Onkyo 805/875 to recover the back channels.

[Spankey]

Peter, not that I wouldn't love a PCM 7.1 track, but aren't we getting the theatrical mix with DD or DTS? We never got PCM quality in the theater, so for me it is nice to have that kind of master quality in the home.

[PeterTHX]

Originally Posted by sltmag

Peter, not that I wouldn't love a PCM 7.1 track, but aren't we getting the theatrical mix with DD or DTS? We never got PCM quality in the theater, so for me it is nice to have that kind of master quality in the home.

Yes, but you know how much more powerful the lossless is over the lossy.

It would just be nice to hear the original discrete rear-surround channel, the same way the other channels usually sound fuller and clearer/cleaner on older soundtracks with discrete mixes (L-C-R-S) repurposed to 5.1

Plus it doesn't bode well for "Cars". Pixar uses Skywalker Sound (inventor of THX Surround EX and implemented by Dolby) for their features so it looks like we won't be getting it on that release either.

[WriteSimply]

If you add one more PCM 24-bit channel to these titles, the bit bandwith takes a hit. That means less bits for video. BVHE could change to TrueHD instead but then y'all would complain about that too. Maybe in five years time BVHE will re-release this title with 6.1 TrueHD/DTS HDMA.

Home version of DD and DTS have better bitrates than te theatrical version.


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