Good news for Sony : Digigami MPEG-2 Encoder destroy h.264

[Magnum PI]

Well a DVD quality DivX movie is ~700mb. Thats very good quality, very crisp.

a feature length movie on 700 MB ?

holy crap batman ! artifacts galore !!!

That's why this whole format war is so retarded, everyone is battling over expensive hardware, while cheap easy codecs are right there to solve the problem. We really don't need more than a 15GB hd-dvd, anything else is overkill.

i agree that 15 GB seems plenty enough for your standards..

 

[Griffith]

let me understand, they use the extra space to compensate the less efficiency of the mpeg2 codec versus H264?

so a film in a 50 GB MPEG2-BD is at same quality then a 9 GB H264 DVD or 9 GB WMV-HD DVD?

so the need of the space of B-Disc where is, if I can use a better codec qith a standard dvd?

and the first 6 months, we will see only 25 GB BD on the market, and only after time, we'll start to see the 50 GB, if I'm not wrong

really meaningless to me

 

[Shifty Geezer]

The difference between codecs diminishes at higher bit rates. As such an MPEG 2 video (of arbitary size) with minimal compression and a filesize of 1 GB will be pretty much identical to the same movie compressed with minimal compression by h.264 to produce a filesize of 1 GB. If that same movie were compressed to 100 MB with MPEG2 and h.264, the h.264 would look better. If to get a 50 GB movie the compression amount is low, the advantages of other codecs will be negated. The only reason to use 'better' codecs is if you are trying to squeeze a movie into a smaller space and so use higher compression, where the older techniques of MPEG2 will produce a lower quality result.

I don't know the ins and outs of the bitrates and stuff, but it's more a case that a 50 GB MPG2 will be equivalent to maybe a 40 GB h.264 (arbitary figures free for correction!) rather than a 9 GB h.264. The 9 GB video would look worse than the big file. MPEG2 has a convenience factor too I believe as it's one of the more common formats for digital distribution already.

 

[scooby_dooby]

The convenience argument is lame. They can afford to spend millions of dollars refitting factories, and engineering new hardware, but can't spend some man-hours to learn how to use some new software? Give me a break.

From the tests I've seen, 16mbps seems like the sweet spot for h264, I'm guessing mpeg2 probably needs ballpark ~32mbps to get the same quality, so probably like a 2:1 real life ratio, 50gb mpg2 roughly equivalent to 25gb mpg4.

As far as 700mb DivX's not being perfect, neither are DVD's They are basically DVD qualit, still quite good quality, and with a 5x - 10x increase you would be getting a near HD image I'd imagine.

 

[Mr. Hanky]

I think where HD-DVD went wrong with pushing the whole mpg4 factor is they didn't go with a physically smaller disc altogether. They missed out on the whole "smaller, kewler" factor. The smaller form factor would have distinguished it more blatantly (techno-futuristic) from the more "conventional" disc size formats. Reduced capacity would dovetail nicely with a "mpg4-only" aspect, not to mention really put the algorithm to work.

 

[Mr. Hanky]

From the tests I've seen, 16mbps seems like the sweet spot for h264, I'm guessing mpeg2 probably needs ballpark ~32mbps to get the same quality, so probably like a 2:1 real life ratio, 50gb mpg2 roughly equivalent to 25gb mpg4.

As far as 700mb DivX's not being perfect, neither are DVD's They are basically DVD qualit, still quite good quality, and with a 5x - 10x increase you would be getting a near HD image I'd imagine.

So the sweet spot (in your opinion) is around 16 Mb/s and your solution to an HD-disc successor is mpg4 on a DVD running around 9 Mb/s? (...gets worse as you exceed 2 hrs, unless you go to extra layers) Well, the early adopter videophiles will really be rushing out for that one, I think... [/sarcasm]

 

[scooby_dooby]

your solution to an HD-disc successor is mpg4 on a DVD running around 9 Mb/s? . [/sarcasm]

yep, that must be my solution all right, seeing as I brought it up and all

 

[Mr. Hanky]

Did you not imagine that 5x-10x the bitrate should give near HD quality with mpg4 on a DVD-sized media? Why just "near HD" quality? You just said Divx on a CD is DVD quality, but 5x-10x the data cannot ensure "true HD" quality?

You should consider the ramifications of the peculiar arguments you pose.

Why? ...because "proposals" always sound nice and flowery, but what really matters is how the numbers really shake out with a real implementation of the proposal.

 

[scooby_dooby]

I can argue the merits of a statement (statement by DivX.com) without it being MY solution. Quit trying to exagerate my words.

You want real numbers?

In this test performed by the BDF(blu-ray disc founders) group:
http://ftp3.itu.ch/av-arch/jvt-site/2004_07_Redmond/JVT-L033.doc

8mbps MPG4 outperformed 24mbps MPG2. As did 12mbps,16mbps and 20mbps h.264 streams.

The 16mbps MPG4 was nearly indistinguishable from the master copy by the participants in the study, while the 24mbps MPG2 was so poor that it ranked lower than even an 8mbps MPG4 clip.

Now, DivX is probably superior in it's HD compression than h.264 is, so I would imagine a movie running at ~10mbps DivX quality would be extremely good, and probably better than a MPG2 stream in the mid 20mbps's.

So, now that we have real numbers 'shaken out' what exactly is wrong with DivX's statement that they can fit 1 90minute HD movie on a DVD. They can. It may not be the absolutute pinnacle of quality, but it's still HD.

 

[AlphaWolf]

Now, DivX is probably superior in it's HD compression than h.264 is, so I would imagine a movie running at ~10mbps DivX quality would be extremely good, and probably better than a MPG2 stream in the mid 20mbps's.

Divx is inferior to h.264.

One year ago best codecs of old MPEG4-ASP standard were comparable to best codecs of H.264 standard, now this situation greatly changed. DivX codec is inferior to most codecs of new standard, even despite considerable growth of its quality comparing to previous version.

From here. Lots of image quality comparisons included in there for those interested.

 

[Mr. Hanky]

So you don't stand behind the solution you posed? Instead, you defer to data read elsewhere, extrapolate to what you "imagine" should work fine, but then you don't take any liability in standing behind your extrapolated proposal?

So to recap, all of the qualifications you gave earlier pertaining to what is "DVD quality" and what is "HD quality" are not even based on your own experiences and observations? They are based on what somebody else has said, and you just reworked the intent to suit whatever argument you want to pose for the day?

Fair enough. We can conclude you only intended to waste our time.

 

[see colon]

this is great, now we have our format war cluttered up with a codec war. all of this is insignificant in the grand scheme of things. as long as the quality is there, the features are there, and all of it is accessable it doesn't matter.

if sony wants to release all of it's stuff using what some people consider an outdated codec more power to them. if image quality suffers or features are stripped because of file size that'll be fuel for the HD-DVD camps. horray for cheaper media. if the quality doesn't suffer and sales are good, sony will have saved some money on production costs by using a codec that is convient for them (assuming they already own equipment that uses MPEG2, and what movie studio doesn't). the extra profits will lead to more frequent releases by sony, and possibly other studios who are using MPEG2. and that's good too.

not that i care either way, i'm waiting for the dust to settle before jumping on board either format.

 

[scooby_dooby]

So you don't stand behind the solution you posed? Instead, you defer to data read elsewhere, extrapolate to what you "imagine" should work fine, but then you don't take any liability in standing behind your extrapolated proposal?

So to recap, all of the qualifications you gave earlier pertaining to what is "DVD quality" and what is "HD quality" are not even based on your own experiences and observations? They are based on what somebody else has said, and you just reworked the intent to suit whatever argument you want to pose for the day?

Fair enough. We can conclude you only intended to waste our time.

lol. You sure type alot for someone who says nothing.

Let me recap because you seem to be a little slow:
- I said 700mb DivX are near DVD quality (this is from my own experience)
- I then said it seems reasonable to assume that a 10x increase in this 'DVD quality' would be a good quality HD signal

Now, I don't see how hard that is to grasp. But you decided to come back with this garbage:
" your solution to an HD-disc successor is mpg4 on a DVD running around 9 Mb/s?"

Something I never even said, my solution? What the heck are you talking about? Regardless, I took your example and showed that indeed, a 8mbps mpg4 has been PROVEN to provide HD quality video (unless you don't consider 24mbps mpg2 HD).

Bottom line is you are talking completely out your ass. Yes, you can fit a HD movie on a DVD using DivX, what's the big deal? Why are you so averse to this? Who cares?

 

[Mr. Hanky]

I followed your point exactly. You just repeated the whole matter with some spin, and I called you on it.

Essentially, you deduced a setup that "should" be fine, but do not stand behind it, when the relevant numbers are brought to bear. Even with an "official study" to back you up, you seem to lack the confidence in championing an 8-Mb/s DVD standard to playback HD content. So which is it- is 16 Mb/s mpg4 the "sweetspot" or is something half that rate quite adequate for a next gen HD standard???

The topic, itself, seems to suggest it is possible for mpg2 to now keep up with mpg4, so your derailment to "mpg4 is good enough for everything anyway" line of thought is misplaced and potentially irrelevant, anyway.

 

[Shifty Geezer]

They are based on what somebody else has said, and you just reworked the intent to suit whatever argument you want to pose for the day?

This strikes me as a very flawed argument. Most of what I know about everything comes from other people telling me instead of me researching it. I know about Xenos structure because Dave wrote an article on it; I never investgated the hardware myself. A paper on subjective qualitative analysis from a test group is valid reference. Indeed it's more worthwhile evidence than any individual's first-hand account.

Scooby may be extrapolating data, but what else are supposed ot do to form opinions on matters we have no experience of? Should no-one be allowed to talk about h264 vs. MPEG 2 (why are we even discussing this topic again?!) without having run their own statiscally qualified research? Should no-one be allowed to discuss possible performance limits of PS3 without actually working on PS3 development? Should no-one get excited over a forthcoming game by reading a review instead of playing it themselves?

I see nothing wrong with Scooby's reasoning. This analysis shows an audience found 8 Mbps h.264 was better quality than 20 Mbps MPEG2. We could do with some bitrates for BluRay to see if this is relevant or not, but without that info, given the information provided, I'd conclude the same as Scooby. h.264 will produce a better quality image ina smaller file than MPEG2 on BRD.

 

[Mr. Hanky]

The problem is he has accepted it as fact, hence we are obliged to accept it as fact. Subsequently, we are expected to believe his extrapolations are then "fact", when they are simply his extrapolations. There should be a difference between, "I have found these guidances to be accurate, so I believe xyz is possible" and "These guidances are now indisputed fact, so my xyz idea shall now be taken as fact, as well". I just think he comes off a bit pretentious with what is "fact" and what he believes, at times (well most of the time).

Either way, we are left with a discontinuity. Is 8 Mb/s mpg4 "enough" for HD (w/o personal observation/validation and because a study "says so"), or is 16 Mb/s still the "sweetspot"? I know which one I'd feel more comfortable with... I find it hard to believe 16 could be the sweetspot (meaning it is the point where the most benefit is gained at a practical bitrate vs. too much is lost at lower bitrates for the bitrate economy achieved and too little is gained at higher bitrates for the capacity required), yet 8 is still in the realm of "good enough". That's a pretty big range.

 

[one]

In a retail disc they use VBR, so comparison with constant bitrate MPEG2/H.264 clips is not very useful to fathom how good an MPEG2 encoded BD video product can be. A professional encoder can allocate higher bitrate in scenes that need it with their own manual expertise and ordinary people won't be able to discern between reasonably encoded MPEG2 and H.264 when the both exceed certain quality.

 

[Mr. Hanky]

Excellent point, and I wonder if dooby was planning on distinguishing that detail at some point.

 

[scooby_dooby]

Either way, we are left with a discontinuity. Is 8 Mb/s mpg4 "enough" for HD (w/o personal observation/validation and because a study "says so"), or is 16 Mb/s still the "sweetspot"? I know which one I'd feel more comfortable with... I find it hard to believe 16 could be the sweetspot (meaning it is the point where the most benefit is gained at a practical bitrate vs. too much is lost at lower bitrates for the bitrate economy achieved and too little is gained at higher bitrates for the capacity required), yet 8 is still in the realm of "good enough". That's a pretty big range.

I think you're just fixated with bit-rate. Would you have such a hard time believing 24mbps MPG2 is 'good enough'? I don't think you would, cause 24 is a nice big number for you. But when faced with a study that shows 8mbps mp4 being better than 24mbps mp2, suddenly you find it hard to believe that that could possibly be HD quality video.

Why? Just cause it has what seems like a low bit-rate? How is that more important than blind studies on image quality? Seems to me the way the picture looks, is more important than the number of bits transfered each second.

The reason 16mbps is considered the sweetspot is two resons. 1 that it's nearly indistinguishable from the master copy, and 2 that increasing to 20mbps showed absolutely no improvement. Going beyond 16mbps is the point of diminishing returns which is why it's the sweetspot.

Anyways, like shifty said, I'm embaressed to be drawn into another long argument about this AGAIN! So, think whatever you want, and I'll keep chuckling at the people defending and pushing a totally outdated and inefficient codec in mpg2.

 

[scooby_dooby]

In a retail disc they use VBR, so comparison with constant bitrate MPEG2/H.264 clips is not very useful to fathom how good an MPEG2 encoded BD video product can be. A professional encoder can allocate higher bitrate in scenes that need it with their own manual expertise and ordinary people won't be able to discern between reasonably encoded MPEG2 and H.264 when the both exceed certain quality.

Or the opposite could be true, and difference could remain. I don't see any reason why mpg2 would benefit more from VBR than mpg4 would.

Talk to the BD development group, they ran the study.

Oh, and BTW, care to point out exactly where it says these tests are performed using a CBR? How do you know it's not VBR at 24mbps average?