[VDPAU] VDPAU HEVC example parser

[Philip Langdale]

On Fri, 12 Jun 2015 15:14:59 -0700
Aaron Plattner <aplattner at nvidia.com> wrote:

> Hi Philip,
> 
> José is away on paternity leave, so I've taken on the task of
> publishing his example HEVC parser.  It's available on GitHub here:
> 
> https://github.com/NVIDIA/vdpau-hevc-example
> 
> José split the X11 part into a submodule, so make sure you initialize
> that after cloning:
> 
> $ git clone https://github.com/NVIDIA/vdpau-hevc-example
> $ cd vdpau-hevc-example/
> $ git submodule update --init
> $ make
> 

So, I built it and ran it, and I have two quick observations:

1) The frames themselves seems ok, so there's hope for my code.

2) The inability to display the frames correctly is exactly the same as
my code. I see the top half of the frame stretched to the full height,
and if I tell it to interpret it as a bottom field, it shows the bottom
half (minus the lines at the bottom).

I don't know why José was seeing something different, but this is the
exact problem I've been talking about. It's simply not possible to
display a decoded frame correctly - even if you manually de-interleave
the two halfs, part of the data is lost in the alignment area between
the two 'fields' and cannot be recovered by an application.

--phil