[OE-core] Enabling x264 support in gstreamer

[Paul Eggleton]

On Tuesday 13 August 2013 20:36:09 Phil Blundell wrote:
> On Tue, 2013-08-13 at 13:26 -0600, Gary Thomas wrote:
> > On 2013-08-13 11:36, Martin Jansa wrote:
> > > On Tue, Aug 13, 2013 at 11:29:10AM -0600, Gary Thomas wrote:
> > >> I see that some of the gstreamer recipes have changed so that x264
> > >> is now a PACKAGECONFIG option.  However, I don't see anything that
> > >> enables this option anywhere.
> > >> 
> > >> How do I get x264 support back - it was working with Poky/Yocto
> > >> just a few weeks back...
> > >> 
> > >> Note: I have imported meta-oe/recipes-multimedia/x264 from
> > >> meta-openembedded into my layers for this [library] package.
> > > 
> > > Add x264 to PACKAGECONFIG in your .bbappend or distro config as
> > > PACKAGECONFIG_append_pn-gst-foo = " x264"
> > 
> > Thanks, although this seems very cumbersome to me.  Is this the only
> > (or at least expected) way for this to work?
> 
> Well, if it's in a .bbappend (rather than distro.conf) then you don't
> need the _append_pn-gst-foo bit, you can just write
> 
> PACKAGECONFIG += "x264"
> 
> which is probably a bit neater and more intuitive.  But if you don't
> already have a .bbappend for that recipe then you might not want to add
> one just for that, it's just a matter of taste which you prefer.
> 
> Other than that, yes, this is basically how PACKAGECONFIG is intended to
> be used.  Some recipes set a default PACKAGECONFIG based on
> DISTRO_FEATURES, but in the general case it's just a variable that you
> need to set appropriately.
> 
> The thing that's a bit unsatisfactory about this approach is that we
> don't have any equivalent to DISTRO_FEATURES_BACKFILL for recipe-local
> PACKAGECONFIG options, which means that introducing new switches for
> things that were previously default-on tends to cause unexpected
> breakage of the sort that you've observed.  It would be good to figure
> out a better way of dealing with that.

The thing is for the option in question wasn't default-on before, it was 
silently on or off depending on the availability of x264. Since x264 was 
unavailable to most users of OE-Core alone the correct thing to do was to 
default it to off, so backfilling couldn't have helped here.

Cheers,
Paul

-- 

Paul Eggleton
Intel Open Source Technology Centre