Will Warner support Blu-ray?

[iknowall]

DirectTV is switching all there HD content to Mpeg4 over the next year or so.

That's because mpeg4 is smaller and need less bandwidth for the trasmission , but this means the quality will not be equal.

 

[iknowall]

I believed that in vast majority of cases mpeg4 yielded a better quality than mpeg2 for a any reasonable 'high' bitrate, but maybe that's not the case.

Mpeg4 lost more information than mpeg2 and will never have better quality.
Just like an mpeg2 compressed don't look as good as the uncompressed one.

 

[AlphaWolf]

That's because mpeg4 is smaller and need less bandwidth for the trasmission , but this means the quality will not be equal.

No it doesn't. Mpeg4 is capable of better compression. Depending on the bit-rates used your quality will vary.

 

[iknowall]

No it doesn't.

Yes it is. You have need less bandwidth for the same video compressed in mpeg4.

Mpeg4 is capable of better compression. Depending on the bit-rates used your quality will vary.

You can use the higest bit rate avaible but the result will never match the quality of the source.

 

[Xenus]

It think he's going for a size for size compression so if you use Mpeg4 to compress it to the same size as the Mpeg2 format. Not sure if that is true though.

 

[Mintmaster]

iknowall, did you even read this?

And the "less compression = better image quality" thing really doesn't stand up to scrutiny. JPEG2000 compresses more than JPEG but can have better image quality at the same file size. I would be pretty shocked if the same is not true of MPEG2 and MPEG4. It's not about more vs. less compression. It's about better vs. worse compression.

WTF are you talking about with 12GB mpeg4 and 80GB mpeg2? Who cares?

He's saying at EQUAL BITRATES mpeg4 will be better quality. It's a better codec. For equal quality, mpeg4 is much, much smaller. If you reduce the compression, mpeg4 will have greater quality. Just because you've worked with masters doesn't mean you're not a moron, and you're proving it to everyone here.

 

[iknowall]

It think he's going for a size for size compression so if you use Mpeg4 to compress it to the same size as the Mpeg2 format. Not sure if that is true though.

You can't have the same size , the mpeg4 one will always be smaller because the codec use by default an higer and more efficent compression.

 

[AlphaWolf]

H.264 can often perform radically better than MPEG-2 video—typically obtaining the same quality at half of the bit rate or less.

From here

If you want higher quality, you can use a higher bit rate. At the same bit rate the mpeg4 should produce a superior image to the mpeg2.

Unless somewhere the blu-ray group has agreed that mpeg4 will always be at half the bitrate of mpeg2?

 

[AlphaWolf]

You can't have the same size , the mpeg4 one will always be smaller because the codec use by default an higer and more efficent compression.

No. There is no 'by default'.

 

[Mmmkay]

From here

If you want higher quality, you can use a higher bit rate. At the same bit rate the mpeg4 should produce a superior image to the mpeg2.

Unless somewhere the blu-ray group has agreed that mpeg4 will always be at half the bitrate of mpeg2?

There are diminishing returns though. The 50GB capacity for Blu-Ray was designed with MPEG-2 in mind not H.264.

I imagine that the processing overhead for H.264 decoding will impose upper limits for bitrates but thats just my speculation.

 

[iknowall]

iknowall, did you even read this?

Yes and this have nothing to do with the video part because you can't compress a video and don' t have artifact. When you compress you are downsampling resolution, color information, a lot of things that don' t came back magically when you decompress.

WTF are you talking about with 12GB mpeg4 and 80GB mpeg2? Who cares?

He's saying at EQUAL BITRATES mpeg4 will be better quality.

Maybe you sould read better before posting, bebause i clearly stated that all two videos in the examples have the same bitrate :

"Make for example that the original hd master have a 100mbps bitrate, and we want to use the same bitrate for the compressed video"

It's a better codec.

No it is not better, it have can compress more the video masking the artifact better , wich do not make it better, considering the tecnology is going to have more space avaible, compressing is what you want to avoid with more space.

For equal quality, mpeg4 is much, much smaller.

You can't have equal quality, once you compress a video in mpeg4 you always have artifact introducted by the compression , at hig bitrate you have little artifact that you maybe not see in a small screen, but if you project the video in a bit screen , you can clearly see them.

If you reduce the compression, mpeg4 will have greater quality.

You have a limit in wich you can reduce the compression , and this limit will always be higer that the mpeg2 one.

Just because you've worked with masters doesn't mean you're not a moron, and you're proving it to everyone here.

Dude get a life, i am spending time giving information because i care about what you think of me , but just to provide some useful information.

You do not have need to make personal attact to me just because you don't like what i say.

Lol i do not work personally with my masters , i work in the industry and when i go to the the post production studios with my works to do wharerer i need , i am used to deal with this problems

 

[iknowall]

No. There is no 'by default'.

Sorry where is. Every codec have a basic compression wich you can't change.

 

[iknowall]

Dude get a life, i am not spending time giving information because i care about what you think of me , but just to provide some useful information.

You do not have need to make personal attact to me just because you don't like what i say.

Sorry there is. Every codec have a basic compression wich you can't change.

Edit : i apologize guys for the grammar errors english is not my fisr language and i can't edit

 

[randycat99]

From here

If you want higher quality, you can use a higher bit rate. At the same bit rate the mpeg4 should produce a superior image to the mpeg2.

Unless somewhere the blu-ray group has agreed that mpeg4 will always be at half the bitrate of mpeg2?

It would be silly to expect that they would go through all the extra computation, expense, etc, to not exploit lesser bitrates. Therein lies the problem. It is essentially giving free license to squish everything down even further beyond something that is already very aggressively squished, rather than concentrate on quality. The whole point of MPG4 was to address increasingly bandwidth starved scenarios, not to improve picture quality. I'm not going to put it down as a terrible, terrible concoction, but it also isn't the "new & improved" mpeg that people think it is just because it has "4" appearing at then end, which most can reason is bigger than "2". You don't use it just because it is there and it is "kewl". You use it because you need to fit a particular scenario. DirecTV is a great example of really "needing" it. Digital satellite is ridiculously bandwidth starved (for the channels they want to push). No doubt, mpeg4 looks like something that can really help out, because truth be told, mpeg2 wasn't cutting it for them even for SD programs. They are looking for something to make it functional, let alone worry about "real" picture quality (which has been the case for the better part of 15-ish years they have been in existence).

...now if they were to offer at least 4:2:2 color space with that mpeg4 (I'd really ask for 4:4:4, but that is probably asking a bit much), maybe that would be something compelling. Otherwise, it is yet another excuse to clamp down datarates ever further at the expense of picture quality, under the guise of, "it's ok, cuz it's teh mpeg4!". It will pass for most people, but not those who really take note of picture quality.

 

[iknowall]

From here

At the same bit rate the mpeg4 should produce a superior image to the mpeg2.

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.

 

[iknowall]

...now if they were to offer at least 4:2:2 color space with that mpeg4 (I'd really ask for 4:4:4, but that is probably asking a bit much),

Why not rgb 10bit 4:4:4 instead of yuv 8 bit 4:2:0 ?

p.s. Well think that only the last sony cinealta can output a 4:4:4 image

 

[randycat99]

Well, sky's the limit, right? ...but I know feasibilities are involved, so anything above 4:2:0 would be a worthy step forward as far as consumer distribution formats are concerned, imo.

 

[AlphaWolf]

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.

Just wrong. More compression does not necessarily equate to lower image quality when talking about different algorithms.

Mpeg4 is a better algorithm for motion pictures and can produce similar quality with much less data than Mpeg2.

 

[randycat99]

...Well, that's the marketing point, at least. Whether or not it really proves out in practice is another case.

 

[AlphaWolf]

...Well, that's the marketing point, at least. Whether or not it really proves out in practice is another case.

Well I know how it works in my practice it really comes down to whether or not media giants choose to abuse compression to maximize profits. It already happens with DVD.