[mythtv] Ticket #4872: Detect if video is letterboxed and switch to corect fill mode

[Mårten Bohlin]

On Mon, Mar 10, 2008 at 9:20 PM,  <mythtv at longhome.co.uk> wrote:
>
> > On Sun, Mar 9, 2008 at 12:32 PM,  <mythtv at longhome.co.uk> wrote:
>  > > I've noticed that 2.39:1 letterboxed in a 16:9 stream also gets
>  > zoomed,
>  > >  meaning part of the broadcast picture is lost. I would have thought
>  > that
>  > >  only content in a 4:3 stream should be zoomed? Right?
>  > >
>  >
>  > That is strange because I test if width/height <= 1.5. And that is the
>  > width and the height of the frame I am processing. So it should not do
>  > anything about streams in 16:9.
>  >
>  > What kind of stream is it? Is it possible that it starts in 4:3 and
>  > then switches to 16:9?
>
>  [Martin Long]
>  Hmmm... it's interesting. As far as I know pixels in UK freeview are not
>  always square, but sometimes are.
>
>  So, sometimes the same resolution is used for 16:9 and for 4:3 - meaning
>  ratio is not a viable means of detecting aspect ratio. I'm not sure what the
>  signalling mechanism is that's used, but this must be available to myth, as
>  it seems to display at the correct aspect.
>
>  I'll see if I can dig around a bit in the code, and try and grab some
>  resolution examples for you. Unfortunately I'm working a lot of hours at the
>  mo, so it might be a little while.
>
>  Martin
>
>
>
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>

That would be great!

I have found the variable "video_aspect" in NuppelVideoPlayer.h which
I guess should contain the correct aspect of the video. I will try
that in the next version of my patch. But there is some other things I
am trying out as well, so it will take a day or two before I release
it.

Mårten