[FFmpeg-devel] movtext decode/encode improvements

[John Stebbins]

On Mon, 2020-04-06 at 15:03 -0700, John Stebbins wrote:
> On Mon, 2020-04-06 at 13:16 -0700, Philip Langdale wrote:
> > On Mon, 6 Apr 2020 11:51:55 -0600
> > John Stebbins <jstebbins at jetheaddev.com> wrote:
> > 
> > > Patch series adds more complete decoding and encoding of color,
> > > alpha,
> > > font size, font name, and style tags for movtext.  It also fixes
> > > a
> > > number of bugs.
> > > 
> > 
> > Hi John,
> > 
> > Thanks for doing all of this! I'll try and take a look at these
> > over
> > the next few days.
> > 
> > 
> > 
> 
> Thanks.  A heads up though.  I need to have a second look at patches
> 10
> and 23 relating to frame sizes and font sizes.  I've been reading
> libass code to get a deeper understanding of how it manages font
> sizes
> and I think I've done that wrong.
> 
> ass font size is relative to a fixed 288 pixel height (I assumed it
> was
> relative to PlayResY in the script).  And mov text font size is
> relative to the specified subtitle track height which should be the
> same as the video height.

After checking carefully, patches 10 and 23 are as I want them. Sizes
are relative to 288 when using override APIs, but are relative to
PlayResY when processing the script.

On the other hand, patch 20 needs a fix.  If the cancel overrides does
not specify a style, it *should* restore the ASS style of the current
dialog, but instead it is returning to the mp4 default style.