Not for AVI it doesn't. Have a look at the data fields for AVI, it can't support anything other than 1:1 aspect ratio.
You're conflating PAR with DAR, there, though.
All I'm saying is that mpeg2 (in header, and optionally in packet information) and DVD-Video (in IFO settings for the domain / PGC) stores very simplistic information in terms of what can be signalled - and that effectively boils down to anamorphic, or non anamorphic.
And the only direct signalling of that, tends to be via pin 8 in SCART connections.
Otherwise, some other method of signalling can apply - and that's stored actually within the video signal, in line23. And that's largely concerned with DAR.
This is why DIVX (the company) has tried to push the .divx media container format to overcome the limitations of AVI.
That's not the only reason, though...
Yeah, they take a 720x576 (PAL) or 720x480 (NTSC) res (4:3 or 16:9 aspect ratio, both of which are anamorphic) source video
It's far from always anamorphic - either widescreen stuff, or 4:3.
And anamorphic stuff just has narrower black letterbox bars encoded in.
in an MPEG container format and literally butcher the vertical resolution down to match the horizontal resolution so that aspect ratio 'appears' correct, e.g. taking a 16:9 720x576 source MPEG video and reducing the vertical resolution to give a file that is 720x405.
It's not surprising then that the resulting video has a reduced file size since you've dumped nearly 30% of the data in converting to AVI!
It's not all valid video information that's dumped, though - there is black borders encoded in most anamorphic widescreen DVD material - especially 2.35:1 or greater - but even with 1.85:1.
And in fairness, mpeg4 can compress the video more before obviously suffering because of it.
Yes, MPEG1/2/4 & VOB containers do support ANY aspect ratio since it has such a data field in the container
All that mpeg2 and / or DVD-Video signals, though (realistically) is anamorphic, or non-anamorphic.
Outside of using SCART connections, how would, say, a standalone DVD player signal such anamorphic, or non-anamorphic picture to the display equipment?
That doesn't mean to say that nothing could be signalled via line23 concerning the DAR of the video contained.
Well as long as we continue to support AVI and create video for it we will have to deal with its limitations. If people continue to support products that have inferior limitations then they only have themselves to blame.
To blame for what?
Personally, I'm not just going to dump well functioning and very useful devices just SIMPLY on principle over the capabilities of the supported video containers.
Just because AVI has no overt, data signalling of aspect ratio, it doesn't matter too much - all AVIs that I've encountered are not anamorphic.
And aspect ration signalling only really matters when it IS anamorphic, so that the display equipment knows to deal with the extra anamorphic detail.
I get that your argument is partly that because of the restrictions of the AVI container, anamorphic video can't be easily signalled - but display equipment can be manually adjusted to deal with it.
It's not ideal, but then people tend to use AVI (containing mpeg4) more out of convenience, than high-end, home cinema viewing.
And in complete and utter fairness - most people I encounter wouldn't have a clue about anamorphic signalling, and the main thing they want is their TV screens filling, whether that's simply by stretching or cropping / pan-and-scanning.
How many people do you think out there have DVD players, widescreen TVs, but still have DVD players outputting letterbox widescreen rather than anamorphic widescreen? Same with DVB boxes (satellite or aerial based).
It's the same principal as overtly restrictive DRM in products - if you buy those products then you're encouraging the manufacturers to produce more DRM riddled products.
It's not the same principle at all.
That succeeds because of money.