Will Warner support Blu-ray?

[iknowall]

Yeah and I'm sure you expect us to believe you..some anonymous FUD poster on the internet.

And i could not care less if you beleave me of not. Well i have a little thing called real word argomentation

I don't think you've established any positive credibility here to make your post worth more than BS.

Im sure you will never argoment your opinion. If i am wrong, i said, expose your argomentation.

I am sure you also had real word experinece with mpeg2hd compression because you tasted how work the hdv.

25GB SL BR movies using MPEG2 from SONY...that's all you need to know.

Hum, sorry last time i used to screen my final project was with a D-cinema system.

I am sure you know i mean i get my hd-d5 master compressed to into an mpeg2hd files , stored it in the avica filmstore server and projected with a barco D cinema projector

http://www.barco.com/digitalcinema/

I am sure you did also and you know how look a D-cinema movie. Yeah sure we are all fools to compress to mpeg2hd instead of mpeg4. It is not that the having smaller files would not benefit the distribution.

Hey mister expert, can you say me if look better a master originated on film or one originated with an hd camera ?

I am sure you have seen both so please can you say me with look better and why ?

I need more education on this argument.

Thanks

 

[PC-Engine]

And i could not care less if you beleave me of not. Well i have a little thing called real word argomentation

Im sure you will never argoment your opinion. If i am wrong, i said, expose your argomentation.

I am sure you also had real word experinece with mpeg2hd compression because you tasted how work the hdv.

Hum, sorry last time i used to screen my final project was with a D-cinema system.

I am sure you know i mean i get my hd-d5 master compressed to into an mpeg2hd files , stored it in the avica filmstore server and projected with a barco D cinema projector

http://www.barco.com/digitalcinema/

I am sure you did also and you know how look a D-cinema movie. Yeah sure we are all fools to compress to mpeg2hd instead of mpeg4. It is not that the having smaller files would not benefit the distribution.

Hey mister expert, can you say me if look better a master originated on film or one originated with an hd camera ?

I am sure you have seen both so please can you say me with look better and why ?

I need more education on this argument.

Thanks

Everyone in this thread agrees that MPEG2 just isn't going to cut it. Let's see if you can convince them.

http://www.avsforum.com/avs-vb/showthread.php?t=411600&page=528&pp=30

 

[iknowall]

Everyone in this thread agrees that MPEG2 just isn't going to cut it. Let's see if you can convince them.

http://www.avsforum.com/avs-vb/showthread.php?t=411600&page=528&pp=30

You can discuss a lot of theories , but real world situation are what matter.
So let's just taking in consideration some facts.

Fact 1 :

Mpeg2hd is the standard used for the D-cinema projection.

Vc1 coded was proposed for the Dcinema compression but no one used it because it can't delivery the quality of the mpeg2hd.

Fact 2 :

Quality of D-cinema is outstanding. It is the best screening quality avaible in the market .
It use mpeg2 and uncompressed audio.

Fact 3 :

D-cinema movies file size can fit on a blu ray 4 layer disk.
We are talking about file with a 60-100 gb size.

Fact4 :

Go to see the D-cinema version of Harry Potter and the Goblet of Fire , and once you will see how it look , you will have no dubd about why mpeg2hd is used.

 

[TrungGap]

I think, IKnowAll does have a point.

As, IKnowAll points out, MPEG2 does have sharper image than MPEG4 at higher bitrates. The problem with MPEG2 is its motion estimation isn't as good as MPEG4 and it has a lot of artifacts. However having said that, the question is how much quality MPEG2 at a higher bitrates can bring to consumer? And is it worth the extra cost? I can see that pro-consumer digial camcorder will want MPEG2 as it easier to do production work than MPEG4.

And finally that MPEG4 is may not bring ultra high quality at higher bitrate, but MPEG4 is just the begining. h264 has rectified all (okay, most) the short comings of MPEG4.

 

[hongcho]

Oh really ? that's strange because sony use mpeg4 codecs for a lot of things, even at professiona lever they use the mpeg4 sp codec, studio profile, for compressing a little bit the video on the hdcam sr format.

Sorry to be a bit rude, but it just shows that you have no idea of the history of MPEG-4 video codec. There is MPEG-4 video codec and there is MPEG-4 AVC video codec. Although they are under the same version name, these two codecs are for very different applications.

The initial MPEG-4 video codec was mainly to improve the low-bitrate coding efficiency. This has been around for a long time. Windows had it for a long time. Some hand-held digital camcorders had it. "I know" (not all, though ) because I used to work in the codec group at Microsoft Windows Media Division.

MPEG-4 AVC (or MPEG-4 Part 10 or H.264) was designed for high resolution and higher bandwidth application. Originally Main Profile was submitted for BD and HD-DVD application. However, the double tests showed some deficiency in detail reproduction. That's where the High Profile comes in. There are other color space improvements, but FrExt (frequency extension) is the main tool that was added to improve the texture detail reproduction.

People just say "MPEG-4". I understand where the confusion is coming from, but still I just have a gripe about this terminology mixup.

Anyway... have you seen the spec for Sony's HD camcorder? Does it do MPEG-4 AVC? No. It just records in MPEG-2. Sony did not want to move beyond MPEG-2. That's why their emphasis on BD storage capacity comes from initially: With MPEG-2, they just needed that much space to accomodate a full-length movie in HD resolution.

Hong.

 

[hongcho]

And finally that MPEG4 is may not bring ultra high quality at higher bitrate, but MPEG4 is just the begining. h264 has rectified all (okay, most) the short comings of MPEG4.

This is another example of what I mentioned earlier. H.264 is the ITU name of ISO's MPEG-4 AVC. They are jointly developed by ITU and ISO groups. Yes, H.264/MPEG-4 AVC is different from low bitrate MPEG-4 video you are used to seeing on PCs.

Your average PCs today have a difficult time playing H.264/MPEG-4 AVC clips at full resolution and bit rate, which is a different story on "MPEG-4" clips.

That's why I prefer to call the new codec H.264 instead of MPEG-4 AVC, but it is still an MPEG-4 video codec... Oh, well.

Hong.

 

[eSa]

This is a theorical number, theorically you can have every bit rate erazing the compression capabilities . But this means that you make the mpeg4 coded the same as another codec, so you make the use of it useless.

Compression = bitrare , where is not way to excape from this

You are wrong all the time. The best so called "mpeg 4" codec is H.264 (AVC) codec. When digital video is compressed with this coded, using the same bitrate than with mpeg2 codec, the H.264 results better quality. This is because H.264 includes block filtering both during encoding (!!!) and then later in decoding phase. Also H.264 improves greatly the inferior mpeg2 blocking scheme... As in a sense, it resembles a quadtree.


Your claims about mpeg4's low maximum bitrate are also false; Page 7, from this document:

http://images.apple.com/quicktime/pdf/H264_Technology_Brief.pdf

Just look at the levels 3.1 - 5.1.

 

[one]

Anyway... have you seen the spec for Sony's HD camcorder? Does it do MPEG-4 AVC? No. It just records in MPEG-2. Sony did not want to move beyond MPEG-2.

As a camcorder has to have a decorder/encoder chip it's reasonable to stay MPEG-2 for now. MPEG-2 is a cheaper solution, not only for Sony but also for all participants in the pipeline, if you once forget the space limit of storage media.

 

[iknowall]

Sorry to be a bit rude, but it just shows that you have no idea of the history of MPEG-4 video codec.

Hum sorry to be rude but , do you have a clue of that hdcamsr is ? Hdcam sr is a tape format that use a professional version of the mpeg4 codec, called mpeg4sp.

There is MPEG-4 video codec and there is MPEG-4 AVC video codec. Although they are under the same version name, these two codecs are for very different applications.

The initial MPEG-4 video codec was mainly to improve the low-bitrate coding efficiency. This has been around for a long time. Windows had it for a long time. Some hand-held digital camcorders had it. "I know" (not all, though ) because I used to work in the codec group at Microsoft Windows Media Division.

MPEG-4 AVC (or MPEG-4 Part 10 or H.264) was designed for high resolution and higher bandwidth application. Originally Main Profile was submitted for BD and HD-DVD application. However, the double tests showed some deficiency in detail reproduction. That's where the High Profile comes in. There are other color space improvements, but FrExt (frequency extension) is the main tool that was added to improve the texture detail reproduction.
People just say "MPEG-4". I understand where the confusion is coming from, but still I just have a gripe about this terminology mixup.

I know this, but like i said, for the D-cinema Mpeg2hd is the only codec used, because it delivery the best quality.

I assure you that you can't have the same quality with the mpeg4 , but if you don't beleave me why don't you see by yourself going go see the dcinema version of the last harry potter so you can undersantd what king of quality we are talking about ?

Anyway... have you seen the spec for Sony's HD camcorder? Does it do MPEG-4 AVC? No. It just records in MPEG-2.

Lol no the cinealta i am talking about do not use mpeg2.

The cinealta is a professional hd digital cinema camera, thesame hd camera used to shoot star wars just to give you an idea.

Hdcam is the format used to compress the video on the tape.
http://www.pci-canada.com/Misc Pag...20SR FAQ.htm

 

[iknowall]

As a camcorder has to have a decorder/encoder chip it's reasonable to stay MPEG-2 for now. MPEG-2 is a cheaper solution, not only for Sony but also for all participants in the pipeline, if you once forget the space limit of storage media.

Not sony nor other brand like thomson viper of panasonic varicam hd professional camcorders use mpeg2 for the hd reconding.

Only consumers camcorders use mpeg2 to compress hd video, with the result of a lot of post production problems.

 

[iknowall]

I think, IKnowAll does have a point.

As, IKnowAll points out, MPEG2 does have sharper image than MPEG4 at higher bitrates. The problem with MPEG2 is its motion estimation isn't as good as MPEG4 and it has a lot of artifacts.

You have no artifact with an hi bit bitrate.

And with blu ray disk where is a lto of space for a very hig bitrate.

Keep in mind that if you have no artifact with an hdv camcorder that compress an hd signal with a 19mbit/sec. bitrate on dv tape , wich is like 13gb , you will never have artifact with the very hi bitrate possible on a 100gb disk.

 

[iknowall]

You are wrong all the time.

Lol not a good start when facts are with me

The best so called "mpeg 4" codec is H.264 (AVC) codec. When digital video is compressed with this coded, using the same bitrate than with mpeg2 codec, the H.264 results better quality.

Hum, no, first, mpeg4 do not work good when you use an hi bitrate because it is not optimized for very hig bitrate.

Second using the same bit rate means using the same compression ratio, so if you are using an hi bitrate no quality difference here.

This is because H.264 includes block filtering both during encoding (!!!) and then later in decoding phase. Also H.264 improves greatly the inferior mpeg2 blocking scheme... As in a sense, it resembles a quadtree.

Wrong again.


Artifac are introduced whi the compression. More you compress, more risk of artifact you have.

So just because mpeg4 have a more compression, it is logical that the codec have to implement more advanced tecniques to mask the artifact.

Mpeg2 do not compress so much so do not have risk of have artifact and do not have need to use more advanced tectiques.

Your claims about mpeg4's low maximum bitrate are also false; Page 7, from this document:

http://images.apple.com/quicktime/pdf/H264_Technology_Brief.pdf

Just look at the levels 3.1 - 5.1.

Wrong again. The commercial codec dont let you to use this bitrate.

I alredy said that you can eraze the compression like you want and have the bitrate you want this this codec. just it lose all it's compression capability.

 

[Mintmaster]

Compression = bitrare , where is not way to excape from this

This is what we're trying to drill through your head, but you keep saying this:

Like i said even at the same bit rate you can't have the same quality because you are still using an higer compression , wich translate in more artifact and in worst image.

So i would make you shocked saying you this...but it is impossible to have the same file size
with the same bitrate comprerssed using mpeg2 and mpeg4.

Same bitrate means the same compression! Bitrate directly corresponds to file size. If the MPEG-4 file is 80GB and the MPEG-2 file is 12GB, then they are NOT the same bitrate.

And I don't know where you get this MPEG4 limit from. I've done plenty of encoding that was quite large. deathlike2 echoed this experience.

Look at simple image compression, using png format I can compress a bmp image to 1/4th it's original file size, yet the image is exactly same quality as the original. How can that be possible!?!??

You don't see the change in quality but this don't means where is no quality loss.

PNG is lossless, buddy. There is no loss in quality, period. MPEG2, however, is lossy, and not nearly as perfect as you make it out to be.

You said "More compression does not necessarily equate to lower image quality" with is false, even with professional codecs compression means lower quality.

You want a video analogy? I could do 5:1 compression with Intel Indeo, and it will look horrible compared to 10:1 MPEG2 compression. I know from experience. AlphaWolf specifically mentioned different codecs, because that is what you're comparing.

As another example, imagine a digital projector using Sony's 4K SXRD chip. You need a resolution of 4000x2000 to take full advantage of the chip. If you want to keep your 180 minute film size to 500GB, then you have around 350Mbit/s. MPEG2 will get you excellent quality at 2000x1000, but MPEG4 will get you full resolution resolution at the same bitrate without a problem. Maybe some aspects of the MPEG2 image will be better, but it won't overcome the factor of 4 in resolution.

There are reasons for sticking with MPEG2, such as keeping a uniform standard, using less processing overhead (and hence having lower cost and less power usage), etc. But saying MPEG4 has lower quality without putting them on equal footing is nonsense.

 

[TrungGap]

You have no artifact with an hi bit bitrate.

And with blu ray disk where is a lto of space for a very hig bitrate.

Keep in mind that if you have no artifact with an hdv camcorder that compress an hd signal with a 19mbit/sec. bitrate on dv tape , wich is like 13gb , you will never have artifact with the very hi bitrate possible on a 100gb disk.

MPEG2 HD quality at 19mb/s can easily be match and surpass by H.264 at half that bitrate. With h.264, there are so many different techniques that are not available in MPEG2 that allows H.264 to be more effecient than MPEG2.

Follow this like to see some testing:
http://www.fastvdo.com/spie04/spie04-h264OverviewPaper.pdf

However, H.264 encoders and decoders are more demanding, so it's not best suited in all applications.


edit: look at Fig8 and cross reference it to Fig9 in the above mentioned url. In figure 8, it's a perceptual testing, and in figure 9, it's PSNR (non-objective testing)..you'll see that at 8mbps H.264 surpassed MGEG2 at 20mbps. Clearly H.264 superiority can not be denied.

 

[iknowall]

This is what we're trying to drill through your head, but you keep saying this:

Sorry this is simply the truth. Compression ratio = bitrate.

Same bitrate means the same compression!

How much time i said same bitrate = same compression ?

i said it so much time in this tread i can't even count off.

You quoted only a typo i made cause i can't edit.


Or do you think that first i state same same bit rate = same compression,
than i state that same bit rate not equal same compression just to say
after again that same bitrate = same compression.

You are ridiculous the only argument you have is a typo.

I always said that same bitrate = same compression ratio.

Same bitrate = same compression = same quality at hi bitrate cause of no artifact.

I said this a lot of time.

just a random quote :

Second using the same bit rate means using the same compression ratio, so if you are using an hi bitrate no quality difference here.

Bitrate directly corresponds to file size. If the MPEG-4 file is 80GB and the MPEG-2 file is 12GB, then they are NOT the same bitrate.

Never say anithing different

And I don't know where you get this MPEG4 limit from. I've done plenty of encoding that was quite large. deathlike2 echoed this experience.

The commercial codec give you a max bitrate you can choise, this is called a limit.

Quite large dont means anything. Define what you mean for quite large.

You can't encode a 1 hour of 720 p video with mpeg4 and make it 500gb.

PNG is lossless, buddy. There is no loss in quality, period.

Wrong. where is a loss of quality compressing from a bmp to jpeg.
AlphaWolf stated that he can compress 1/4 the image without losing quality.
Compressing an image from bmp to a jpeg with 1/4 of the size is not loss free.

MPEG2, however, is lossy, and not nearly as perfect as you make it out to be.

I never say mpeg2 is not lossy, nor even sayd it is perfect, i said it have a better quality
than mpeg4 cause it is less compressed.

A perfect codec is an uncompressed codec.

You want a video analogy? I could do 5:1 compression with Intel Indeo, and it will look horrible compared to 10:1 MPEG2 compression. I know from experience.

And wich part of "even with professional codecs compression means lower quality."

did you forget ?

Since when intel indeo is a professional codec like hdcam or dvcprohd ?

AlphaWolf specifically mentioned different codecs, because that is what you're comparing.

As another example, imagine a digital projector using Sony's 4K SXRD chip. You need a resolution of 4000x2000 to take full advantage of the chip. If you want to keep your 180 minute film size to 500GB, then you have around 350Mbit/s. MPEG2 will get you excellent quality at 2000x1000, but MPEG4 will get you full resolution resolution at the same bitrate without a problem. Maybe some aspects of the MPEG2 image will be better, but it won't overcome the factor of 4 in resolution.

How do you know that dubling the compression will not introduce visible artifact ?
You are assuming that the mpeg4 coded have an illimitating compressing power, and that can magically remove all the effect you get from the compression.

How do you know that the mpeg4 video would not be with visible artifact ?

This wondering and dreaming is cool and all, but the truth is that Dcinema use mpeg2hd files because it give the best quality.

And this is a fact.

There are reasons for sticking with MPEG2, such as keeping a uniform standard, using less processing overhead (and hence having lower cost and less power usage), etc. But saying MPEG4 has lower quality without putting them on equal footing is nonsense.

Again i repeat, digital cinema use mpeg2hd only compression because it give a better quality.

No one use mpeg4 nor Vc1.

get over it.

 

[iknowall]

MPEG2 HD quality at 19mb/s can easily be match and surpass by H.264 at half that bitrate. With h.264, there are so many different techniques that are not available in MPEG2 that allows H.264 to be more effecient than MPEG2.

Half bitrate means double compression. You have a video that have qith mpeg2 have a 1:22 compression and you are biching because you have to have so much compression, now you are saiyng that with mpeg4 you could have 1:40 compression with half bitrare and a similar quality.

How in the hell would prefer woring with video that 1:40 compression instead of a 1:22 compression ?

Follow this like to see some testing:
http://www.fastvdo.com/spie04/spie04-h264OverviewPaper.pdf

However, H.264 encoders and decoders are more demanding, so it's not best suited in all applications.


edit: look at Fig8 and cross reference it to Fig9 in the above mentioned url. In figure 8, it's a perceptual testing, and in figure 9, it's PSNR (non-objective testing)..you'll see that at 8mbps H.264 surpassed MGEG2 at 20mbps. Clearly H.264 superiority can not be denied.

You did not undestanded the sense of my post. It was not to comparate mpeg4 to mpeg2.

You sayd "he problem with MPEG2 is its motion estimation isn't as good as MPEG4 and it has a lot of artifacts."

and i replyed saying that this is not true becasue even at a bitrate of 19mbit/sec. mpeg2 don't get artifact so you will never have artifact with the bit rate availbe on a 100gb blu ray disk.

 

[TrungGap]

Again i repeat, digital cinema use mpeg2hd only compression because it give a better quality.

I find that hard to believe, even BDA's testing shows that h.264 is better than MPEG2. DCinema uses mpeg2 might be for other reasons, such as existing professional equipments are pretty much mpeg2 or licensing cost.

Fact 2 :

Quality of D-cinema is outstanding. It is the best screening quality avaible in the market .
It use mpeg2 and uncompressed audio.

BTW, why is the audio uncompressed? I assume that there are bunches lossless audio compression available for you guys to use.

 

[TrungGap]

Half bitrate means double compression. You have a video that have qith mpeg2 have a 1:22 compression and you are biching because you have to have so much compression, now you are saiyng that with mpeg4 you could have 1:40 compression with half bitrare and a similar quality.

How in the hell would prefer woring with video that 1:40 compression instead of a 1:22 compression ?

I'm not sure I fully understand you. Bitrate is the final out of the compression, not the input bitrate of the source material. Assuming we're on the same page, then...I think you are assuming that compression ratio is tied to quality. But it's not.

If I were to compress a file using huffman compression the compression ratio is lower than that of LZW (in most cases as there are always exceptions). Does that mean LZW is lower in quality...? No, both will give me the exact same result, just different compression ratio. LZW is a lot more complex than Huffman.

MPEG2 doesn't have same level of complexity of H.264. H.264 has a much better motion comprensation. It has variable block size (MPEG2 it's 16x16). Motion vector estimation in H.264 is more precise than MPEG2 (which is limited to 1/2 pixel). Eh, bascially h.264 compression is more complex than MPEG2 which allows it compress video to a smaller file without taking a hit on quality...and in most cases even better.

Look at the doc I mentioned earlier. It clearly shows PSNR of h.264 is better than MPEG2.

 

[iknowall]

I find that hard to believe, even BDA's testing shows that h.264 is better than MPEG2.

Dcinema don't have the same bitrate limitation.
At high bitrare mpeg2 look better.

DCinema uses mpeg2 might be for other reasons, such as existing professional equipments are pretty much mpeg2 or licensing cost.

I dont care if you find hard to beleave, it is just a fact.
All and i mean all dcinema films are compressed to mpeg2hd. I did the same so i know.
If you dont beleave me ask at anyone you know did the encoding for the avica server and he will confirm.

There are no othe reason than quality.

BTW, why is the audio uncompressed? I assume that there are bunches lossless audio compression available for you guys to use.

Because you have so much space that compressing audio make no sense at all.

Uncompressed audio is a dcinema feature and give you the best quality and audio dont take that much space.

 

[iknowall]

I'm not sure I fully understand you. Bitrate is the final out of the compression, not the input bitrate of the source material. Assuming we're on the same page, then...

The compression you use make the bitrate of the final video.

You said that with mpeg4 you , in the same size, can have 2 times the resolution right ?

This mean that the compression ratio of the mpeg4 video is twice as the one of the mpeg2 file.

but this means that the mpeg4 video will have half the bitrate.

Because compression ratio = bitrate.


Now the questio is : how can you be sure that compressing the video twice you will have no artifact ?

Lowering the bitrate due to the compression make artifact and make you lose quality.

I think you are assuming that compression ratio is tied to quality. But it's not.

It is unless it is someghing magic. To be compressed an image have to be downsampled, it get's the color dowsampled, the croma downsampled, you lose information.

This cause loss of quality. More the compression ratio is higer, more quality you lose.

This is why the uncompressed master will always look better, because the image do not have any alteration.

If I were to compress a file using huffman compression the compression ratio is lower than that of LZW (in most cases as there are always exceptions). Does that mean LZW is lower in quality...? No, both will give me the exact same result, just different compression ratio. LZW is a lot more complex than Huffman.

Every video compression make a loss.

Ok so just to make an example, when you compress a 720p video with the dvcpro codec, it downsample it from the original 1280 x 720 to 960 x 720 and get the croma downsampled
from 640 to 480.

Explain to me how can this not translate in a loss of quality ?

MPEG2 doesn't have same level of complexity of H.264.

Do mpeg2 have need of having it ? No

Why ? because it use less compression and it have no need to be more complex

H.264 has a much better motion comprensation. It has variable block size (MPEG2 it's 16x16). Motion vector estimation in H.264 is more precise than MPEG2 (which is limited to 1/2 pixel). Eh, bascially h.264 compression is more complex than MPEG2 which allows it compress video to a smaller file without taking a hit on quality...and in most cases even better.

Do mpeg2 have to compress the video to a smaller file ? No

So are this advancement for the mpeg2 uselsess ? yes.

Look at the doc I mentioned earlier. It clearly shows PSNR of h.264 is better than MPEG2.

I dont dubd what, but mpeg2 do not have need to be better in this aspect because it not have to do the same work , mpeg2 will never get in similar situation, and was not supposed to do.

with a 100gb disk you dont have space problem to deal with and you want to avoid more compression as you can.

Mpeg2 wont compress the video like mpeg4, and this is why it look better, because it have less compression and more bitrate.