[FFmpeg-user] When to determine frames are progressive or interlaced ?

[Roger Pack]

On 12/19/12, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> tank pranav <akshar_tank <at> yahoo.com> writes:
>
>> I would like to know when to determine frames are
>> progressive or interlaced ?
>
> (Depending on how you define "interlaced" frames:)
> To the best of my knowledge, only visual inspection
> tells you, but there is a filter named "idet" that
> tells you if the video is interlaced.

I have no real idea, but I thought I saw once that MPEG picture
headers mentioned if the picture was interlaced or not
(http://davidbloom.home.mchsi.com/readme/readme.html search for
"picture headers")
FWIW :0