misdetected dv frame aspect ratio

[dericed]

MediaInfo detects all four frames as 4/3 aspect ratio, when the 3rd is only half so and the 4th is not at all.

The VAUX with aspect ratio of frame 1 and 2 look like:

550702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffff
55170060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
552702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffff
55370060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
554702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffff
55570060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
556702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffff
55770060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
558702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffff
55970060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

If the fourth char after '61' is 0 then it's 4/3 and if it's 2 then it's 16/9. Here all vaux source packs show 4/3.

In the 3rd frame it's like this:

5f0702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
5a170060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
5b2702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
5a370060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
5b4702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
5a570060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
5b6702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
5a770060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
5b8702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
5a970060ffff00ff610380fcff62ffffffff63ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

Odd and even dif sequences have different aspect ratios, maybe this is ok as it's interlaced, but it's odd. Note that ffmpeg calls this frame as 16/9 and visually that appears correct, though from analysis it seems 50% 4/3 and 50% as 16/9.

The fourth frame is:

500702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
502702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
504702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
506702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff
508702ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff60ffff00ff610302fcff62ffffffff63ffffffffffffffffffffffffffffffff

Note that only odd DIF sequences have aspect ratio data, the even sequences have empty VAUX, but all the existing aspect ratio data is 16/9. Mediainfo calls this 16/9, but dvrescue does not start a new because of the discrepancy.

SEATTLETAPE_aspectratio.dv.zip

[JeromeMartinez]

when the 3rd is only half so

this is a difficulty here, for the moment I have only one "boolean" (e.g. it i4/3 or 16/9) for all attributes, should we move to a ratio of each possible value for all attributes? or another attribute saying that there is incoherency in the frame for an attribute?

[dericed]

I'd say the priority is to note that the 4th frame is 16/9 so set a new node. For 3rd frames I know it's half 4/3 and half 16/9, but in this case ffmpeg gets it right so I'd prefer to using the other DIF sequence as the dominant to at least match behavior.