Industry Insiders Q&A Thread: only Questions to insiders please - Page 24  

Hal, I a sorry for lack of reply. I have been thinking about the points being made some of which was just mentioned by the Tom and Tom. And was hoping the hardware folks would be fielding the question.

Anyway, the problem is actually rather complex. HD DVD can have three sources of content, all of which has to be mixed together: primary video, PiP and graphics. All three could run at different rates/resolution, up to 60i. The easiest path therefore, is to "upconvert" all to 60i and then have a mixer. Since all displayes have dual mode de-interlacers (i.e. can do the simple inverse telecine or proper de-interlacing of 60i sourced content), there is little harm in this. Send out straight 60i and the display will then just do the simple inverse telecine if that is all that is needed. Send it a complex one with 24p main video (converted losslessly to 60i) with inset video of 60i and the display can do the proper motion adaptive de-interlacing and still get you a pleasant picture.

If you want to output 24p, then you have to convert everything down to this. To do this well, and not butcher the PiP, you would need to good de-interlacer which is the solution used in Samsung and Toshiba recorder in Japan. You don't want to do a bad job here because if you do, the damage done, can not be undone. Whereas in the 60i case, you don't suffer from this.

So in an odd way, 1080i may be superior to 1080p24. This is why I and some others have talked about 120hz output at some point, which is a nice multiple of both 60i and 24p and does not require repeating fields.

And yes, as Tom mentions above, there is no assurance in the player that you can just do the inverse telecine (at least I don't think there is). So while in BD players which for now, don't support PiP, the case is simpler as far as outputting 1080p24, I think they face the same problem. Maybe Keith can say if any of the BD players based on their platform support 24p, or they also resort to same technique as Samsung/Toshiba....

Note that I am not 100% sure my explanation and understanding of the issues is correct. I think I am close but I am still doing a bit more research on it. For now, let me say that Kevin on my team, is a happy camper, running his Toshiba HD DVD player at 72 hz, driving his CRT projector. Of course, he has a high-performance GPU to do rate conversion for him of the inset video, but there is good existence proof of "24p" output from HD DVD already.

Hope this at least provides some of the key data points until we get the definitive answer.

Great :).

HD DVD has specification for an alternative track, called S-EVOP, which can be stored outside of the disc. Then the menu system, iHD, can call upon it and stich it with the rest of the movie. Note that this other video has a data limit of 15 Mbit/sec so it would have to be an advanced codec to support HD well.

So iHD takes care of telling the player which segments to play and in which order. In other words, it is no different than having a playlist in Windows Media player with different tracks coming from different parts of your machine including the network.

15Mbit/s for the peak or avg? Could this other video overlay the main feature as PiP?
Could this 15Mbits/s all used by a lossless external sound track? If so, then HD DVD may have a bandwidth of 45Mbps?

Oh, I'm sure you weren't expecting this follow-up, but here goes anyway:

Can you please elaborate? :D

On which part? Or are you pulling my leg :)?

(running out to drive up to LA from San Diego so may be out of pocket until late tonight after the LA AVS Forum HD DVD meet)...

I bolded the part in my original post; does Kevin have some special version of the Toshiba HD DVD player?

I remember he use an HTPC to play HD DVD.

Amir,

Thanks for the response. It sounds like PiP is what's causing some of the complication, then. Well, I guess Tosh needs to put a better de-interlacing (or maybe scaling) solution the box, then, as all reports seem to indicate it's 720p output is sub-standard compared to 1080i. I really don't want to depend on my display to do the conversion.

Sorry for badgering, but this information was so different from what the impression I had I wanted to see if l could get it straight. Maybe some of the other insiders can add to this.

One more thing, is the PiP part of the problem always present, even when not in use (I'm assuming yes)? So just by turning off PiP I still wouldn't get a better progressive signal?

Be interesting as well to see how this plays out for BD once they get PiP going.

The laptop? That's a player with the high end GPU. And 72Hz is a common enough refresh rate.

Gary

How about 600Hz? Then we can do away with all those pesky 50Hz/60Hz issues too. :)

That schism remains, and continues to complicate things. I wish line frequency stuff had just gone away, and the standards had been defined at 24/48/72 Hz for all.

Gary

I belive there is some confusion on this. On the ha-a1 the displayed numbers 480,720,1080 are refering to the resolution of the imput.
all output over HDMI is 1080 thus

480 to 1080 sd disks
720 to 1080 (no disks yet avaiable)
hd to 1080 HD-DVD disks

I belive I have this right

Those conditions would include the overwhelming majority of HD-DVD titles, since they're encoded as 24p on the disc and it's the player doing the telecine in a very consistent way. It's not like SD DVD where the telecine is done before storing the material on disc, often inconsistently, and can vary from scene-to-scene.

--
Steve

While the various audio and video mixing options in HD-DVD are interesting, I think they're also creating a drag on the format because people don't understand how it affects the ability to output Dolby Digital, 1080p24, etc. It would be really great if future players could have some sort of "pure direct" mode that would just take a single audio track and pass it through without decoding or mixing it, and also take the video and pass it through at 1080p24 without PIP or any other video overlays.

--
Steve

Talk,

A few questions if you could please answer them:
Since you work on BD-J:

1. When will PiP be supported?

2. Players that are out before then, will they be firmware upgradeable to use the PiP features?

3. When will BD-Live see the light of day?

Other questions since you're an insider:

1. When can we expect to see 50GB media?

2. What percentage of the titles will use 50GB media?

Ron is both right and wrong.

He is right in that all of the issues he mentions are possible. He is wrong in saying that you can't ingnore the flags and output 23.976.

The SD DVD version of InterVideo's WinDVD does this. It sends 23.976 straight to the video renderer in Windows. If you watch something like the x-files, then you get a mess. If you watch something like Star Wars Episode III, then you get a clean image. The HD DVD version of WinDVD does the same thing. I am able to do this today on the Toshiba laptop.

In an interesting way, a lack of a feature in the current VC1 encoder for BD and HD DVD makes this more robust. We have not implemented inverse telecine in the VC1 encoder. So we don't have real mixed mode support. This means you must send a 24p (or 23.976) source into the encoder. This ensures that there are no flag errors on the main feature. If you have mixed content, then you encode it as interlaced.

The problem you will run into is when you try and play back IME or bonus features. That will look ugly. IME may also cause problems for any device doing inverse telecine. It is running at a different rate than the main feature.

BD made the wiser choice. Even though displays now support inverse telecine for 1080i, those algorithms still drop lock when they think a cadence error occurs. With a true 24p out, there is no chance for this to occur.

Of course there are two BD players this year that output 1080i from the decoder and use a 3rd party chip to convert to 1080p. The first is the Samsung, the second will be out in a couple of months.

The biggest problem I see with 24p in the now is displays re-syncing as the output switches between the various rates.

@amir, or any other insider that might know:

do any of the current/forthcoming titles make use of "side information" in the encoding process? if so, to what extent?

is the current gen Toshiba player equipped to use this information?


PS amir, you haven't answered the question that you asked people to ask you, which title will be the first avc encoded hd dvd title in usa???

stacey,

[a] when you say BD made the wiser choice, i am a bit confused; are you saying that hd dvd CANNOT also output 24p (not talking about the current gen tosh player, but any future player that is designed accordingly)...are you saying this is not permitted/provided for under hd dvd?

[b] since sony is delayed to october, do you mean the pioneer or the panasonic is employing the same design choice as the samsung; i.e., to use a deinterlace chip?

[c] do you mean if there is mixed content on the disc, like 24p as well as 30/60i? that would be a nightmare on any of my current displays as they don't re-sync very quickly.

TIA

So the question for the Toshiba HD-A1/D1/XA1 & RCA player is; can the Broadcom chip ignore the flags and output 23.976?

Does the Toshiba hardware design allow a "Pure Direct 24p Film" output possibility via a firmware change?

Allow such a possible optional user choice with the user knowing/warned that it messes up IME and any extras that are not sourced as 1080p/24?

Bob

I would second the further explanation of why BD made the wiser choice.

I'd also add that if you're bothered about 24p output you'll probably not want to mess it up with interactive stuff... If having two play modes 'Direct 24p' and normal is the compromise then I'd be happy.

Ian.

I'm not an insider, but I'm with Stacey on this one. As I asked in one of the threads were this was discussed here:

http://www.avsforum.com/avs-vb/showt...&&#post8030782
There is a difference between not being about to give the user an option and there being cases where the user would want to disable it.

--Darin

Not to challenge your technical skills, but I read Ron's comments differently. After looking at the HD-DVD requirements he cited, I believe what the gist of his comments were that you couldn't ignore the flags and still be "legal" (as in compliance) to the documented HD-DVD spec. Yes outputting at 23.97 is possible, but only if you choose to ignore the spec and it's requirements as they are currently defined.
Again, this is not to question your analysis, but to put it into a different perspective.

b2b

Wow...there went three hours of my life :)


Q: When do folks expect to see a DIY HTPC solution for either HD DVD or Blu-ray in the United States?

Just stating a CY Quarter when you expect things to come together for either format would be great to know, I know you can't share what particular companies w/ particular products are doing what when.

Amir,

Question about VC-1 encoding, excuse me if it has already been answered.

When you put the master data trough the encoder I'll guess, there is more to it than just hitting the "Encode" button and later a 100% quality HD DVD pops out at the other end. How does it actually work? How many man hours does it take in average to encode a HD DVD?.
(By the way i just came back from a photo session tour/vacation in Grand Canyon with my Canon 20D :) - that place is amazing)
Thanks for your time - I really wonder how you can find spare time for this - just fantastic!!

Moderator's kind reminder..

In this thread, make sure you're either asking a question of an insider or you are an insider responding to the question. See the first post.

I have a feeling that it's the one he's showing tonight at the meet-and-great.

Amir,

Could you keep this idea in mind for future releases? If your involved in any meetings or so on with studio execs. This might be a potential marketing idea (if it hasnt already been discussed and shot down). I bet it would be a huge draw.

Thanks.

Wouldn't you need a 120 Hz display that can accept a 1080p120 signal for that to be possible?


lymzy, remember that the required HD DVD buffer is 140 MB and because HD DVD is a random access format you would have to store the entire soundtrack to the buffer. Even excluding that issue how would you get the entire audio track into the buffer? Finally how would you sync the audio track with the video track?

PiP will be supported in players supporting BD-Live, which I expect to be supported by the PS3 and all 2G players (but will have to be announced by the respective player manufacturers). While I believe PiP could be supported by all BD players (that is, I believe the hardware to support it is already present), it would be up to an individual manufacturer whether to enable support outside of a fully BD-Live compliant player.
I certainly expect to see them this year. I imagine it'll be a very small percentage this year (perhaps 5 or 10% of new titles introduced), with the number rising slowly as manufacturing costs drop and the creative community finds interesting ways to make use of the added capacity.

Note that these are purely my predictions; I have no concrete knowledge of plans related to these questions.

- Talk

Unfortunately not. That title is from Paramount and we don't have permission to use their content for tonight's meeting.

BTW, this AVC title is not the sign of things to come. It is the sign of things that have come and gone :). This was the first title encoded and after that, they switched to VC-1 and they are quite pleased with the encodes....

I have provided another hint on this topic if you are dying to know which title it is in some other thread (yes, you have to work hard for it :D).

Unfortunately, the area that we have next to no influence in is the titles. That is a purely business decision for the studios and we try to not poke our nose in it. Lest we want them to tell us how to design VC-1 :).