On Tue, 20 Dec 2016 12:29:20 +0100
Vittorio Giovara <[email protected]> wrote:

> >>> Also h264/hevc are not the only video codecs on the planet. Implicit
> >>> defaults in the data type is the wrong way to go about this, it takes
> >>> away any kind of flexibility for no real gain.  
> >>
> >> What kind of flexibility is there now? I cannot think of a case where
> >> the current state is nothing more than added complexity. The gain,
> >> besides simpler handling of the range, i sthat the data type correctly
> >> reflects the only two states in which the range can be found.  
> >
> > Undefined is a perfectly valid state in my book.  
> 
> The problem is that the range is never undefined, or when undefined it
> is assumed to be limited. This is true in several BT specifications
> for example.

You're free to assume that unspecified means limited in whatever code
consumes the range flag. But the decoder should output what the
bitstream contains whenever possible.

In mpv, we actually have a function to determines "missing" colorspace
related fields if they're set to unspecified. This way we avoid
ambiguous interpretation of such unspecified flags before they are used
by whatever code is using them. It's especially necessary for the
colorspace, which is usually guessed from the video resolution. You
could invent such a function for AVFrames too.
_______________________________________________
libav-devel mailing list
[email protected]
https://lists.libav.org/mailman/listinfo/libav-devel

Reply via email to