how to crop/resize without aspect ratio error

[FOO]

I'm sure a good many of these seemingly arbitrary numbers
are because TV was originally completely analog, and
had no pixels. (except for the shadow mask in Color TV)
.... and a discrete number of scan lines

[ronnylov]

To be more specific:I was talking about DV resolution.

The same thing applies to DV resolution. Many DV cameras fills the whole 720x576 picture but then you can multiply the width by 59/54 and you get a picture size of 786x576 if you want to convert DV to square pixels.

[Dragonsf]

But when I resize my original non-square pixels but any number (other then 1), I'm changing the original PAR.There is really no use (as far as I can tell) to do this, because in the end DVD calls for 720x576 (or 704x576) again.
I still can't see any reason, why the original pixel is not square (besides it was defined in such way)

[FOO]

But the horizontal storage resolution has nothing to do with reality.
The player will spit it out at whatever the MPEG2 header says
is the Display aspect ratio.
720 x 576 is 1.25 5:4
720 x 480 is 1.5 3:2
They end up on the TV as 4:3
352 x576 and 720 x 576 both look the same on your TV

[Dragonsf]

My tests results:
Anamorphic with SVCD doesn't work the same as with DVD.
I made an anamorphic sequence of 1 min and tries every encoding combination with tmpgenc.The only suceesful encoding was to set aspect ratio to custom (at the same AR as the size before resizing, i.e. 720x336.This isn't really anamorphic, as it seems, that tmpgenc resizes this format again.
the only way, to get full screen anamorphic be shown as 16:9 on my TV, was to switch the TV set into 16:9 mode.I tried with 2 different DVD players.

[DJRumpy]

Just resize the vertical to 480 height for 1.77 aspects (no letterboxing), 460 vertical with 20 letterboxing for 1.85, or 360 vertical for 2.35:1 aspects. These are good for players that do support the 16:9 DAR, but only if you have a 16:9 television. You can place a 4:3 dar on these. This type of disc would be compliant (with a 4:3 DAR of course), but it will not display correctly on a 4:3 television.

If you do not have a widescreen TV, or your player doesn't support the 16:9 DAR, you have to resize to 360 vertical for 1.77, 344 for 1.85, and 272 for 2.35. Add letterboxing as appropriate. These would of course have a 4:3 DAR.

[Dragonsf]

Thatt was exactly what I did with the expected results.
That is:there is no automatic switch to 16:9 like a DVD can do.

[DJRumpy]

That is somewhat expected, which is why I think (opinion only, since we can't find anything official one way or the other ) that 4:3 is the only truely supported aspect ratio for SVCD. The fact that many players that support SVCD but do not 'auto-letterbox' a 16:9 SVCD to 4:3 would seem to support that idea. I simply encode mine as 16:9 aspects within a 4:3 DAR, since I do own a widescreen. That way my discs are compliant regardless. Nero also complains that the disc is non-compliant with a 16:9 DAR flag.

Unless you plan to get a widescreen television any time soon, I'd suggest you just use the 4:3 letterboxed mpeg.