Quote:
Originally Posted by SeeMoreDigital
Actually you are wrong.
In the case of MPEG-2 DVD or DTV the 720x756/480 or 'D1' pixel frame size is always encoded along with either 4:3 or 16:9 DAR (ie: aspect ratio signalling). It is never distributed at 1:1...
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Yes, 720x756/480 is always anamorphic (either for 16:9 or for 4:3), I never questioned that.
The real issue is that, according to the DVD-Video specs, only the 720x756/480 resolution can have the 16:9 flag, everything else (for example 352x288/240) can only be flagged as 4:3. Which is the real problem. If your content is 16:9, you have to use the 720x756/480 resolution (if you use the DVD-Video format), which means you have to use higher bitrates, which means you have to use at least 4GB for a half-decent picture.
So, where was I wrong? As I said in my previous post, DVD-Video forces you to use the 720x756/480 resolution if you want widescreen (16:9).
Quote:
Originally Posted by rwill
"Sure it looks bad, but at least it's small". Mpeg-2 video could have done this as well, SVCD being one popular standard.
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No, it couldn't. And it's not for lack of trying by various people in the past.
First of all, SVCD doesn't do 16:9 anamorphic. Not reliably at least, aka with the players capable of signaling it properly (for 16:9 TVs) or putting black bars (for 4:3 TVs). So, you have to letterbox during authoring and manually crop/zoom in the TV's widescreen settings when viewing on a widescreen TV. DVD-Video only does widescreen at 720x756/480, which requires high bitrates (for the standards of the day, at least). And that's before we take into account the fact MPEG2 degrades much worse than MPEG4 ASP.
Basically, it all comes down to this: Have you tried squeezing a 2-hour movie on an SVCD? Or even on 2 SVCDs? It's unwatchable, even on a CRT television. You have to go to 4GB (DVD) at minimum, which was considered a huge filesize back then. Meanwhile, a 2-hour movie on 2CDs with MPEG4 ASP at 640x360 offered acceptable quality (for the standards of the day, at least), and even 1CD was considered watchable.
Now, why is MPEG4 ASP used today? The answer is it's pretty small (700MB or 1400MB) and plays on pre-H.264 players. Nobody will download a 4GB (or 4.38GB) MPEG2 file for their car DVD player or for their non-HD TV-DVD combo in the kitchen. At least that's what I get by looking at the availability online. And for their big screen TVs, they will download the H.264 version
