544x416 PAR?

[teknix1]

Hi,

I'm working on a resolution converter just to help me out on conversion projects and I'm a bit boggled about the strange 544x416 resolution. Could anybody please tell me what is the pixel aspect ratio for this resolution? Seems like Auto GK and Handbrake on Mac can produce these resolutions. Somehow this is related to the iPod or cell phones.

If you don't know what the PAR is, how would you go about converting a source to this resolution? What source would it be?

I've seen many posts about people saying this resolution has an AR of 4:3 but it really isn't, it's 17:13.

Any help is appreciated.
Thanks
Nic

[jagabo]

DAR = SAR * PAR

Any storage aspect ratio (frame size) can be any display aspect ratio. But 544x416 is only 2 percent off from 4:3. So it's probably 4:3 DAR, 1:1 PAR, rounded to the nearest multiple of 16 (width and height).

[guns1inger]

The need to meet mod4 or mod16 pixels sizes means that there is often a small variation from the true source aspect ratio.

[teknix1]

That sort of confirms what I was thinking the only problem is that if you're going to convert a higher resolution source that has an AR of 4:3 to 544 by something, it would be 544x408, which gives exactly 4:3.

Still doesn't completely make sense to me could this perhaps be because of overscan that was not removed before scaling???

Thanks for the replies

[jagabo]

Nobody will notice a 2 percent AR error on a cell phone. They would notice 4 pixel black bars at the top and bottom and complain.

[teknix1]

Perfect, makes sense.

Thank you.

[jagabo]

It's also possible the source was resized to 554x416 and cropped down to 544x416.