Yet another Anamorphic Question

[Vietwoojagig]

I captured a movie with EyeTV. The picture size of PAL is 720x576.

After croping there is 706x414 left.

Selecting anamorph strict it sais:
Source: 720x576, Output 706x414, Anamorphich: 753x414 Strict

This is a PAR Width of 16 and a PAR Height of 15.

Why?
Why is it not 1:1? Where does the "15" comes from?
Does this means, that EyeTV captures the picture somehow anamorphic? But the size of 753 width does not make any sense in my opinion.

How can I ensure, that I always have the same anamorphic ratio as it is in the source?

[mduell]

http://trac.handbrake.fr/wiki/AnamorphicGuide

[Vietwoojagig]

http://trac.handbrake.fr/wiki/AnamorphicGuide

This answer was not really helpful in the first place. The real answer was on a page linked from a page where that page was linking to.
Helpfull would have been a direct reference to this page: http://www.doom9.org/index.html?/capture/par.html.

So after all, it seems, that information about the source PAR and/or the source anamorphic picture size could help to understand the strict anamorpic output values.

[jbrjake]

Um, there is plenty of information about pixel aspect ratio and why it isn't 1/1 on the page mduell linked you to.

For one of many examples from the guide:

Pixel Aspect Ratio ¶

In fact, it is displaying 720*480. Only, the video track is telling VLC: "Display this with wide pixels instead of the square ones you usually use." So instead of an image of square blocks, it becomes an image of wide rectangular blocks.

Because computers think of video in terms of square pixels, VLC has to figure out what arrangement of square pixels is needed to reproduce the image in its correct dimensions. It does this by multiplying the storage width (720) by a ratio: the Pixel Aspect Ratio, or PAR. By default, the PAR is 1:1. With that ratio, what you see is what you get—square pixels. The video is stored and displayed with the same dimensions. In order to recreate 16:9 pixels from 1:1 pixels, the ratio is 32/27 (16*2 / 9*3). For every 32 square pixels across, it uses 27 square pixels up and down. You already know this, another way: it produces the same results as multiplying the height (480) by 16/9. Multiply 720 by 32 and divide that by 27, and you end up with 854, the display width in square pixels.