[HD-DVD Challenge] MPEG2, VC-1 and H264 with real uncompressed source movie [Archive] - Page 6

benwaggoner

14th October 2006, 19:45

If you were to refer to kilobytes per second, it'd be correct to use 1024, though I'm sure codecs would get it wrong enough that the distinction would be meaningless. But as long as you're talking about bits, not bytes, powers are always in 1000s.

K==1000

All the international standard units are properly power of 10. The power of 2 numbers should use a "iB" at the end, like KiB.

http://en.wikipedia.org/wiki/KiB

It's confusing, as there are plenty of areas where people use the wrong name for their units, but we should all be moving towards being precise about this, especially as storage gets bigger. It's a significant difference between a TB and a TiB.

Dethis

17th October 2006, 20:21

Here's an MPEG-2 test clip for you. It is an elementary stream.

http://www.w6rz.net/ed.mpv

And the statistics (including VBV) file.

http://www.w6rz.net/ed.txt

Ron

:thanks:

zambelli

19th October 2006, 00:09

VC-1 Encoding
Profil & Level: AP@L3 except specific restrictions
Max GOP lenght: 15 frames
Maximum bitrate: 20.0 Mbps or 28.0 Mbps
Buffer size: 14745 Kbits for principal HD video stream
Horizontal Vector Range: +/- 1024 pixels
Vertical Vector Range: +/- 256 pixels
Other Restrictions Setting: max adaptative GOP at 15, max adaptative bframe at 2

You must use these bitrate/size for encoding:

HD-DVD with "super bitrate" video stream and simple HDDVD authoring:
18 Mbps (Max at 28.0 Mbps) for video stream with +/- 1 % for bitrate tolerance
HD-DVD with "medium bitrate" video stream and standard HDDVD authoring:
12 Mbps (Max at 20.0 Mbps) for video stream with +/- 1 % for bitrate tolerance
HD-DVD with "low bitrate" video stream and standard HDDVD authoring:
6 Mbps (Max at 20.0 Mbps) for video stream with +/- 1 % for bitrate tolerance
Are these your final rules? Can I re-encode the WMV9 videos now? I will be using the "generic" Vista/WMP11 encoder DMO, but a few of us at MS are also working on some encodes done with our professional VC-1 encoder. You don't have to wait for the latter - let's just tally the results as they come in and keep the highest score.

Also, I vote that the current results be reset/deleted due to the change in spec rules. I also propose that from this point on any result submission must be accompanied by the PSNR log, SSIM CSV and SSIM summary generated by the respective Avisynth plugins. I've seen too many results just "show up" in the results table without anything to back them up. It's not that I don't trust you :), I just like a transparent competition. Also, if you're going to record the highest score, you should probably also note the software, revision, and encoding settings used.

arfster

19th October 2006, 03:47

Ditto - I've got plenty of spare computer cycles as well, and wouldn't mind a shot :-)

ps could anyone possibly seed the Elephant Dreams Torrent?

zambelli

19th October 2006, 09:49

ps could anyone possibly seed the Elephant Dreams Torrent?
Short of getting a torrent, your best bet is to download Wackget from http://millweed.com/projects/wackget and then run this command:
wget -r -l 1 -A png http://media.xiph.org/ED/ED-1080-png/
This will download each source PNG file from the ED website.

bob0r

19th October 2006, 14:35

...

NB: we can use HD-DVD structure too on simple DVD DL 12 cm at 8.5 GB ... ;-)

Let me be stupid here (1024 bytes used):
DVD9
8533311488 B
8333312 KB
8138 MB
7.94 GB

arfster

23rd October 2006, 13:55

Short of getting a torrent, your best bet is to download Wackget from.....

Thanks, worked. With Sagittaire's latest restrictions here....

http://forum.doom9.org/showthread.php?p=886879#post886879

...., my h264 12mbit encode come up with 49.675dB from the x264 prompt (see attached). Probably not comparable with the previous records, because this has 20mbit rather than 29mbit peak limit, and different b-refs. Still, it looks pretty much pristine compared to the original, so SSIM is probably 92/93 or so.

I'll run the avisynth psnr/ssim2 scripts later and edit the logs into this post, but have we settled on these new restrictions? The encodes take about 10 hours (max everything, 3-pass), or perhaps about 4 hours with 0.5 less dB, so it's no great problem to run them overnight.

Edit: end results from Avisynth are...

PSNR min: 38.8690
PSNR average: 49.6843
SSIM2: 94.22763493

arfster

24th October 2006, 15:41

... and 6mbit, again done with latest Sagittaire settings:

Average PSNR: 46.3835dB
Min PSNR: 34.5825db
SSIM2: 89.50666592

Hugely impressive SSIM for a 6mbit encode, although the min PSNR is low. Watching that sequence it doesn't really show though, as much of the bitrate is being consumed by background stuff that doesn't need to be terribly detailed.

arfster

25th October 2006, 19:47

18mbit, same conditions as before but 28mbit peak.

Average PSNR: 52.0348
Min PSNR: 37.0249
SSIM2: 95.87262239

The min PSNR is worse than 12mbit, but that's a single frame glitch. Even in the 2800-3200 hardest sequence, it's all at 45-50db. Clearly the higher 28mbit peak helps hugely here.

Thus, for the 3 encodes:

Mbit SSIM2 PSNR
6 89.5 46.4
12 94.2 49.7
18 95.9 52.0

The 18mbit looks a bit like overkill from the above, and from a quick look I can't tell the difference visually between it and 12mbit. Related to this, I found:

http://www.compression.ru/video/codec_comparison/01_subject_codec_comparison/subject_codec_comparison_part3.htm

Scroll down, they have correlations for SSIM, PSNR and VQM vs subjective rankings of 50 people. It's pretty clear that SSIM is massively superior to the other two.

Sagittaire

26th October 2006, 01:12

unfortunaly x264 don't respect the vbv buffer in multipass mode ...

zambelli

26th October 2006, 02:24

unfortunaly x264 don't respect the vbv buffer in multipass mode ...
Sagittaire, why is H.264 buffer size defined according to BluRay spec whereas the VC-1 buffer size is defined according to HD-DVD spec? It gives H.264 an unfair advantage. The buffer restriction is imposed by the HD-DVD and BD spec respectively, not by the codecs, so why set them differently?

Sergey A. Sablin

26th October 2006, 07:16

unfortunaly x264 don't respect the vbv buffer in multipass mode ...

even more - it doesn't follow HRD model in any RC mode, because devs use mpeg-2 vbv model instead of what is described in the spec. Plus CBR has no padding - so even for mpeg-2 vbv model overflow is it's usual state for low complexity scenes.

btw, we send you latest encoder a week ago - did you have a time to play with it? any results?

Sagittaire

26th October 2006, 10:08

btw, we send you latest encoder a week ago - did you have a time to play with it? any results?

oh sorry (I will make mail for thanks and questions) ... :thanks:

1) Your encoder work perfectly. Better quality than the last version with new setting.
I Try to find the best possible setting for metric and/or for my eyes.

2) I have problem with streameyes. Perhaps limitation for evaluation version. I will see that.

Sagittaire, why is H.264 buffer size defined according to BluRay spec whereas the VC-1 buffer size is defined according to HD-DVD spec? It gives H.264 an unfair advantage. The buffer restriction is imposed by the HD-DVD and BD spec respectively, not by the codecs, so why set them differently?

Well it's true. It's really strange but buffer for each codec seem different for HDDVD. For principal video stream VC1 use higher buffer than MPEG2 ( 14 745 Kbits vs 9 781 Kbits) and H264 buffer seem higher than VC1 ( 30 000 Kbits vs 14 745 Kbits). I don't know the exact value for H264 but 30 000 Kbits seem compliant with HDDVD.
http://forum.doom9.org/showthread.php?p=882932#post882932
http://forum.doom9.org/showthread.php?p=882963#post882963

And you say yourself that:
Well, sure, but then we're doing a disservice to all the codecs here. If the spec allows for a bigger buffer, why not use it?

Sergey A. Sablin

26th October 2006, 10:14

oh sorry (I will make mail for thanks and questions) ... :thanks:

1) Your encoder work perfectly. Better quality than the last version with new setting.
I Try to find the best possible setting for metric and/or for my eyes.

2) I have problem with streameyes. Perhaps limitation for evaluation version. I will see that.

feel free to email/pm me or mutek for both questions.

zambelli

26th October 2006, 22:35

I'll ask again: why is VC-1 buffer size 14745 kbits, while H.264 buffer size is 30000 kbits?

guada 2

26th October 2006, 23:04

I'll ask again: why is VC-1 buffer size 14745 kbits, while H.264 buffer size is 30000 kbits?

I don't know, but H264 size max is 32182 Kbits.

arfster

27th October 2006, 01:29

unfortunaly x264 don't respect the vbv buffer in multipass mode ...

Yeah - I only noticed that after doing the encodes :-) Oh well, no great hassle, it was on lowest priority so wasn't taking time from anything else, and the box is on 24/7 anyway.

Anyone got a tool to check buffer use yet? The Elecard tool doesn't work with h264 encodes (HRD parameters not present).

MuTeK

27th October 2006, 04:36

The Elecard tool doesn't work with h264 encodes (HRD parameters not present).

Elecard BufferAnalyzer operates with all streams (MPEG-2, MPEG-4 AVC/H264 and VC-1), but as it was mentioned correctly, the stream should have HRD parameters. If there are no such parameters, it’s impossible to analyze such streams.

Ps I think it makes sense to ask devs of x264, why they are reluctant to write these parameters into the stream first.

arfster

27th October 2006, 04:43

Elecard BufferAnalyzer operates with all streams (MPEG-2, MPEG-4 AVC/H264 and VC-1), but as it was mentioned correctly, the stream should have HRD parameters.

Sorry, meant to write x264 rather than h264. It's obviously not the Elecard tool's fault here.

akupenguin

27th October 2006, 05:17

why they are reluctant to write these parameters into the stream first.
Because it's complicated. The standard does not allow you to just write down the buffer size and maxrate used. If you include any hrd parameters, you must include an sei packet at every keyframe detailing the state of the vbv buffer. And stuff like that.

I use vbv.pl (http://akuvian.org/src/x264/vbv.pl) to verify vbv ratecontrol. It doesn't look at the stream at all, just the output of `x264 -v`.

MuTeK

27th October 2006, 06:13

Anyone got a tool to check buffer use yet?

Tektronix.. :) (http://www.tek.com/products/video_test/mts4ea/index.html)

Sagittaire

27th October 2006, 08:50

I'll ask again: why is VC-1 buffer size 14745 kbits, while H.264 buffer size is 30000 kbits?

Simply because each codec use differents values for the buffer.

According to the HD-DVD specs, these are the allowed VBV buffer sizes:

1222000 bytes for MPEG2 Main Video HD (or 9 781 000 bits)
1843200 bytes for VC1 Main Video HD (or 14 745 000 bits)
xxxxxxxx bytes for H264 Main Video HD (or xx xxx xxx bits)

The HDDVD buffer is unknow and confidential for H264 but according Sergey A. Sablin 30 000 000 bits is compliant with HDDVD spec.
http://forum.doom9.org/showthread.ph...932#post882932
http://forum.doom9.org/showthread.ph...963#post882963

I don't know, but H264 size max is 32182 Kbits.

coud you tell me pls where did you get these numbers from?

zambelli

27th October 2006, 09:13

The HDDVD buffer is unknow and confidential for H264 but according Sergey A. Sablin 30 000 000 bits is compliant with HDDVD spec.
Not according to my info. Our resident HD-DVD guru says: "Both codecs, within HD DVD, are 1843200 bytes for main video. There is no other option."
It would not make sense to have H.264 have a buffer nearly twice the size of VC-1's because the two codecs are expected to use very similar bitrates.

Sagittaire

27th October 2006, 09:56

Not according to my info. Our resident HD-DVD guru says: "Both codecs, within HD DVD, are 1843200 bytes for main video. There is no other option."
It would not make sense to have H.264 have a buffer nearly twice the size of VC-1's because the two codecs are expected to use very similar bitrates.

MPEG2, VC1 and H264 can and must use the same buffer for main HD video stream (14 475 Kbits) for HD-DVD ... ???

Your "HDDVD guru" can confirm that ... please. It's strange because Sergey A. Sablin (Elecard/MainConcept H264 dev) doesn't say that ... ???

Sergey A. Sablin

27th October 2006, 10:07

Not according to my info. Our resident HD-DVD guru says: "Both codecs, within HD DVD, are 1843200 bytes for main video. There is no other option."
It would not make sense to have H.264 have a buffer nearly twice the size of VC-1's because the two codecs are expected to use very similar bitrates.

right now I'm checking dvd specification for high definition video version 0.9 (probably outdated, but I haven't newer version) and see that 30 mbit buffer is allowed for H.264 for HD content. While VC-1 has restriction of 1843200 bytes as you said.

latest version I know is 1.01, but I haven't it yet, so maybe some changes were done, but I dont know any.

arfster

27th October 2006, 12:30

Someone requested stats from my encodes above to check for buffer compliancy, thought I'd post here in case anyone else wants to use them also......

benwaggoner

28th October 2006, 04:40

right now I'm checking dvd specification for high definition video version 0.9 (probably outdated, but I haven't newer version) and see that 30 mbit buffer is allowed for H.264 for HD content. While VC-1 has restriction of 1843200 bytes as you said.

latest version I know is 1.01, but I haven't it yet, so maybe some changes were done, but I dont know any.
I confirm that all HD DVD codecs use the same buffer size, and we should be using the above value for this test.

I'm also concerned by the fact that H.264 is allowed larger motion vectors in the test than VC-1. I haven't looked at that in as much detail, but I suspect that is likely in error as well.

Sagittaire

28th October 2006, 10:55

I confirm that all HD DVD codecs use the same buffer size, and we should be using the above value for this test.

Really good news ... I will use the same buffer for all codec. But it's strange that MPEG2 MP@HL can use 14 745 KBits for the buffer ... ???

I'm also concerned by the fact that H.264 is allowed larger motion vectors in the test than VC-1. I haven't looked at that in as much detail, but I suspect that is likely in error as well.

Well +/- 256 or +/- 512 don't change really the quality for 1080p source. Anyway I think that the compliant value is +/- 512 for HDDVD (typically level 4.1 limitation like reference frame)

I want use WME Studio Edition beta1 for make test in batch mode. I can use the same registry command than WM9E? You can done the best possible hddvd.epr profil?

Here my actual hddvd.epr

<?xml version="1.0" standalone="no"?>
<Project xmlns="http://microsoft.com/schemas/WMESE.xsd">
<Name>Untitled</Name>
<Id>{3FE09976-4820-4AA7-93A5-9ABC9D5C5E1D}</Id>
<TempOutputDirectory>C:\Documents and Settings\JFL\Local Settings\Temp</TempOutputDirectory>
<Timeline>
<Sources>
<Source id="1">
<SourceUrl>C:\Program Files\Windows Media Components\Encoder\HDDVD.avs</SourceUrl>
<VideoStreamOverride>
<StreamIndex>0</StreamIndex>
</VideoStreamOverride>
</Source>
</Sources>
<Tracks>
<VideoTrack>
<Name>Untitled</Name>
<Clips>
<Clip>
<Id>{70B844C1-CB67-484D-8EAE-833C2CC488F3}</Id>
<Name>HDDVD.avs</Name>
<SourceRef id="1" streamIndex="0"/>
<MarkIn>0</MarkIn>
<MarkOut>400400000</MarkOut>
<Preprocessing>
<Resizing>
<Cropping>
<Left>0</Left>
<Top>0</Top>
<Width>1920</Width>
<Height>1080</Height>
</Cropping>
<Dithering>true</Dithering>
</Resizing>
</Preprocessing>
</Clip>
</Clips>
<Streams>
<VideoStream>
<IsStreamSelected>true</IsStreamSelected>
<Name>Untitled</Name>
<Codec>{31435657-0000-0010-8000-00AA00389B71}</Codec>
<EncodingMode>PeakVBR</EncodingMode>
<EncoderComplexity>4</EncoderComplexity>
<DecoderComplexity>1</DecoderComplexity>
<KeyframeDistance>600</KeyframeDistance>
<ProduceAllFrames>true</ProduceAllFrames>
<Bitrate>6000000</Bitrate>
<PeakBitrate>20000000</PeakBitrate>
<BufferSize>480</BufferSize>
<GOPType>closed</GOPType>
<LoopFilter>true</LoopFilter>
<Lookahead>16</Lookahead>
<BFrames>2</BFrames>
<ChromaSearch>true</ChromaSearch>
<MVRange>-1</MVRange>
</VideoStream>
</Streams>
<Width>1920</Width>
<Height>1080</Height>
<FPS>25.000000</FPS>
<OutputInterlaceMode>Progressive</OutputInterlaceMode>
<AspectRatioIndex>0</AspectRatioIndex>
<XPixelAspectRatio>1</XPixelAspectRatio>
<YPixelAspectRatio>1</YPixelAspectRatio>
</VideoTrack>
</Tracks>
</Timeline>
<Output>
<AsfOutput>
<OutputUrl>C:\Program Files\Windows Media Components\Encoder\Untitled.wmv</OutputUrl>
<AutoAdjustRate>true</AutoAdjustRate>
<Metadata>
<String Name="Title" Value=""/>
<String Name="Author" Value=""/>
<String Name="Description" Value=""/>
<String Name="Copyright" Value=""/>
<String Name="ISAN" Value=""/>
<String Name="ADID" Value=""/>
</Metadata>
</AsfOutput>
</Output>
</Project>

bond

28th October 2006, 12:24

I don't know, but H264 size max is 32182 Kbits.where do you have that info from?

Sergey A. Sablin

29th October 2006, 10:11

I confirm that all HD DVD codecs use the same buffer size, and we should be using the above value for this test.
first of all I should say that I'm not against of fair comparison when all codecs use same settings for buffer, but I still dont understand where did you get your information from (except of some guru), so my question is:
which version are you refering to? It is clearly stated above which information and from where I have - you just told "I confirm..." Any details? Or gentlemans from MS dont need to prove their statement in this forum?
Right now I have august 2006 version and see that no changes on buffer constrains were made since 0.9. (and if you have a doc then you should see that AVC constrains are way weaker then 30 mbit, so I'm really confusing by your statement of identical parameters for all codecs)

I'm also concerned by the fact that H.264 is allowed larger motion vectors in the test than VC-1. I haven't looked at that in as much detail, but I suspect that is likely in error as well.

I'm also concerning by the fact that MPEG-2 vbv model (and VC-1, cause it is the same) is much easy/effective to use when buffer state is near floor. Seems to be a bit more advantage than a length of MVs. And it seems the should be a difference for buffer parameters if buffer models are different, dont you?

Sagittaire

29th October 2006, 14:03

Right now I have august 2006 version and see that no changes on buffer constrains were made since 0.9. (and if you have a doc then you should see that AVC constrains are way weaker then 30 mbit, so I'm really confusing by your statement of identical parameters for all codecs)

For principal HD video stream buffer are:
- 9781 Kbits for MPEG2 MP@HL
- 14745 Kbits for VC-1 AP@L3
- 30000 Kbits for MPEG4 AVC HP@L4.1

Yes or No for this august 2006 version ... ???

I'm also concerning by the fact that MPEG-2 vbv model (and VC-1, cause it is the same) is much easy/effective to use when buffer state is near floor. Seems to be a bit more advantage than a length of MVs. And it seems the should be a difference for buffer parameters if buffer models are different, dont you?

VBV limitation are typical hardware limitation:
- Max bitrate is fixed for the optical speed (DVD 3X or HDDVD 1X).
- Max buffer is fixed by the hardware decoder chip buffer capacity.

IMO in theory all the codec could use the same buffer. IMO chip for HDDVD and BD decoding will be the same and in theory the max buffer for principal HD stream could be 30 000 Kbits for all video codec in this case. It's strange.

Sergey A. Sablin

29th October 2006, 14:39

For principal HD video stream buffer are:
- 9781 Kbits for MPEG2 MP@HL
- 14745 Kbits for VC-1 AP@L3
- 30000 Kbits for MPEG4 AVC HP@L4.1

Yes or No for this august 2006 version ... ???

I already said that content of both HD-DVD and BluRay specs is confidential. So I couldn't disclosure it.
I already said that 30 mbit is allowed for AVC for HD-DVD.
If zambelli or benwaggoner have different information then at least it is interesting where it came from.

(well, maybe ron/drmpeg has hd-dvd spec, so try to ask him about this)

VBV limitation are typical hardware limitation:
- Max bitrate is fixed for the optical speed (DVD 3X or HDDVD 1X).
- Max buffer is fixed by the hardware decoder chip buffer capacity.
Thanks, I'll take a note of this

IMO in theory all the codec could use the same buffer. IMO chip for HDDVD and BD decoding will be the same and in theory the max buffer for principal HD stream could be 30 000 Kbits for all video codec in this case. It's strange.
Specs have some different specific restrictions on decoding (particularly on avc decoding), so probably there will be different chips.

trbarry

31st October 2006, 15:09

Sergey A. Sablin

31st October 2006, 15:18

The buffer size thing seems to be a complex issue, with two different specs and some proprietary info. But I feel fairly strongly that for the purpose of this shootout both (all) codecs should be restricted to the same size. Since it is such a limiting factor it just wouldn't be a good comparison otherwise as it greatly affects min psnr.

- Tom

I'm not against this as I already said - let's use same size for all codecs. (but mind that different buffer models lead to different quality is some situation with same buffer parameters)

zambelli

1st November 2006, 10:43

I already said that content of both HD-DVD and BluRay specs is confidential. So I couldn't disclosure it.
I already said that 30 mbit is allowed for AVC for HD-DVD.
We can settle the matter easily: can you specify the page and paragraph where HD-DVD spec indicates that H.264 buffer is 30 Mbits? Perhaps we're just looking in completely different places or somebody is misreading the spec. We should get on the same page - literally. :)

Sergey A. Sablin

1st November 2006, 10:50

We can settle the matter easily: can you specify the page and paragraph where HD-DVD spec indicates that H.264 buffer is 30 Mbits? Perhaps we're just looking in completely different places or somebody is misreading the spec. We should get on the same page - literally. :)

till now I even didn't heard that you have a spec - you always talking about some mystic guru.
And how we can see at any page if you even didn't tell yet which version of spec do you have? (or your guru)

PS: I didn't said that spec restriction is exactly 30 mbit, instead I said it is allowed ;)
PSS: check your PM box - lets discuss spec there

guada 2

1st November 2006, 21:52

Hello,

Sagittaire & bond:
I think it is not important to know the place.

Specs (and others) are a great factor for VLD+IQ and for "IDCT+MC".........

Other thing:
i think it is most interesting to compare Buffer size and PSNR : buffer size (macroblocks) / buffer sizes (for different values of ε) and to find the best quality (dB); but it's very complicated on Higher résolution especially in Real Time.

However i am a little confused...
when i read that:
On level number :5 (0-1)
max. Bitrate :135000 kbps
max. Decoded: 135000 kbps
picture buffer: 41310.0 kByte
max. decoder rate: 589824 macroblocks/s
max. Framesize: 1920x1088 @ 72fps

and this new level for super high-resolution video to MPEG-4 AVC/H.264 Profiles 5.2 (4096*4096):

Level number: 5.2 (expérimental)
Max macroblock processing rate MaxMBPS (MB/s): 983040
Max frame size MaxFS (MBs): 65536
Max decoded picture buffer size MaxDPB (1024 bytes): 69120,0
Max video bit rate MaxBR (1000 bits/s or 1200 bits/s): 240000
Max CPB size MaxCPB (1000 bits or 1200 bits): 240000
Vertical MV component range MaxVmvR (luma frame samples):
[-512,-511.75]
Min compression ratio MinCR: 2
Max number of motion vectors per two consecutive MBs
MaxMvsPer2Mb: 16

Bye.

Sagittaire

2nd November 2006, 00:21

guada 2

2nd November 2006, 17:16

HDDVD and BD use H264 HP@L4.1. For this level "max bitrate" is 50 Mbps and "max cpb" is 62500 Kbits but HDDVD and BD don't use these max vbv specifications ...

OK. thanks

But are you sure BD use H264 L4.1.
I doubt a little, perhaps you are right then what sort of BD use 3.2?

sillKotscha

4th November 2006, 02:49

sorry to disturb this very informative thread based on very high technical knowledge. This is far beyond my enthusiasm for video encoding as my beloved hobby, but... :)

after reading the whole thread I came across one post by Sagittaire from 24th September 2006 (http://forum.doom9.org/showpost.php?p=879364&postcount=204)...

he states:

If it's true use MPEG2 for HD-DVD become in practice impossible if you want high quality because max bitrate at 19 Mbps is really to low for 1080p and MPEG2. The quality will be like HDTV MPEG2 source ... horrible.

as a remark to
Another thing to consider is that real HD-DVD's contain multiple audio tracks (some of which are relatively high bitrate) and PIP secondary video. On AVSForum, one of the compressionists is claiming that full featured HD-DVD disks have the primary video peak bitrate capped at 19 Mbps. So coding with 29.4 Mbps peak bitrate may not be something that happens in the real world of HD-DVD authoring.

Ron

as it seems this is really true for real life environments as well...

a german homecinema magazine was testing the very first devices available for the end user, shipped directly from the US to germany in early august. Participant were the Toshiba HD-XA1 for the HD-DVD camp (the tested discs use VC-1) and the Samsung BD-P1000 for the Blu-ray camp (the tested discs use MPEG2). They were testing in a full HD compliant way = projectors capable of native Full-HD resolution of 1920 x 1080 (VPL-VW100 and Qualia004 by sony).

I won't go into detail here but to summerize their conclusion is easy... BD (MPEG2) was clearly beaten by HD-DVD (VC-1) in terms of visual satisfaction. For them the limiting factor was clearly MPEG2 compression BUT to be fair in conjunction with lower disc space (at the moment you'll only see single layer BD = 25GB vs. HD-DVD = 30GB) + Sony for example insist on using PCM as audio source (for the time being!!) and was not using Dolby Digital + or DTS HD. That might have changed though but it was true for the tested discs.

As for the starting of a new technology this is somewhat "bad luck" for the BD camp and it seems(!!) as HD-DVD/ VC-1 will make it...

here you will find the test (http://www.cine4home.de/tests/sonstiges/BDvsHD/BRvsHDDVD.htm) and even if you can't read german, you can scroll down to see which movie/ studio titles were tested for each technology...

just my 2 cents

drmpeg

4th November 2006, 05:17

OK. thanks

But are you sure BD use H264 L4.1.
I doubt a little, perhaps you are right then what sort of BD use 3.2?
BD allows L3, L3.1, L3.2, L4 and L4.1 levels. I would expect the possible usage is:

SD video = L3
1280x720p24 = L3.1
1280x720p60 video = L3.2
1920x1080i30 or 1920x1080p24 = L4
1920x1080i30 or 1920x1080p24 over 20 Mbps = L4.1

Ron

Sagittaire

4th November 2006, 10:48

I won't go into detail here but to summerize their conclusion is easy... BD (MPEG2) was clearly beaten by HD-DVD (VC-1) in terms of visual satisfaction. For them the limiting factor was clearly MPEG2 compression BUT to be fair in conjunction with lower disc space (at the moment you'll only see single layer BD = 25GB vs. HD-DVD = 30GB) + Sony for example insist on using PCM as audio source (for the time being!!) and was not using Dolby Digital + or DTS HD. That might have changed though but it was true for the tested discs.

As for the starting of a new technology this is somewhat "bad luck" for the BD camp and it seems(!!) as HD-DVD/ VC-1 will make it...

just my 2 cents

Well be carefull ...

1) This challenge test only codec for HDDVD. BD has other vbv specification and very better max bitrate than HDDVD (in practice certainely something like 35 Mbps for video stream)

2) The MPEG2 implementation from Sony is perhaps not the best available ... see atrac codec from Sony for example. IMO MPEG2 encoding (with best possible implementation) at 24 Mbps will done always very better result than VC1 encoding at 12 Mbps.

3) The Samsung SAP is not a very good BD player.

4) IMO HD-DVD camp use certainely pre-process for the master (denoising and perhaps sharpening) for make "better visual" encoding.

guada 2

4th November 2006, 23:15

BD allows L3, L3.1, L3.2, L4 and L4.1 levels. I would expect the possible usage is:

SD video = L3
1280x720p24 = L3.1
1280x720p60 video = L3.2
1920x1080i30 or 1920x1080p24 = L4
1920x1080i30 or 1920x1080p24 over 20 Mbps = L4.1

Ron

:thanks:

Originally Posted by drmpeg
Another thing to consider is that real HD-DVD's contain multiple audio tracks (some of which are relatively high bitrate) and PIP secondary video. On AVSForum, one of the compressionists is claiming that full featured HD-DVD disks have the primary video peak bitrate capped at 19 Mbps. So coding with 29.4 Mbps peak bitrate may not be something that happens in the real world of HD-DVD authoring.

Ron

I would think that is was possible HD DVD L4.1 obtain some 34 Mbps (peak bitrate)...

1) This challenge test only codec for HDDVD. BD has other vbv specification and very better max bitrate than HDDVD (in practice certainely something like 35 Mbps for video stream)

OHOOOOOH...

popper

29th November 2006, 19:43

http://www.highdef.com/library/glossary.htm

hi crypto, just started reading this thread and wanted to put the original UK and EU case of 25/50/P rather than the oddball US standards, remember that the UK's BBC and its other content producers has already set the standard PAL 25/50 P in much of the world.

for instance the newest BBC DVB HD trials have already set some industry standards that the much of the world will be using soon enough, heres a link to the bbc delivery outlines
http://www.bbc.co.uk/guidelines/dq/pdf/tv/hd_summary_delivery_formats_v1_3.pdf

they take their DK very seriously and protect their markets very carefully http://www.bbc.co.uk/commissioning/production/hd.shtml

in all their official documentation you will see its 25/50 and progressive and sometimes 100 for future inovation.

im pritty sure that the other vast pal/partner countrys markets are also not looking to use oddball framerates were standard 25/50 serves just fine and has done for a very long time.

why dont the US simply convert to PAL 25/50 ? as its better all round after all , and these new HD sets and related kit are already mass produced by our eastern friends in all flavours of PAL (with NTSC bolted on for convenience) so its not hard to get these new 1080P sets etc and over time the price will fall.

and thats not even mentioning all the Professional HD progressive 25/50 pal camera's and related kit that the UK film/broadcasters and content makers commission that everyone wil use one day.

zambelli

29th November 2006, 20:38

hi crypto, just started reading this thread and wanted to put the original UK and EU case of 25/50/P rather than the oddball US standards, remember that the UK's BBC and its other content producers has already set the standard PAL 25/50 P in much of the world.
By "oddball" I'm assuming you're referring to 29.97. The argument was never about whether this should be 25 or 29.97. The argument was whether it should be 25 or 23.976, and 23.976 (or 24 fps) is far from an "oddball" standard.

why dont the US simply convert to PAL 25/50 ?
They will, right after they switch to metric. :D

Wheh will PAL support 24 fps playback without speedup? ;)