Ryan Rix wrote:
I'm currently trying to start a KDE beat for next week's
Fedora Weekly
News, and was hoping I could get a little clearing up on the whole state
of QtMultimedia in Qt 4.6.
I'd second Eike's recommendation not to mention Phonon yet, we don't have
all the information we'd like to have ourselves at this point.
In any case, some of the things you wrote are incorrect:
What I know:
* Qt pulled Phonon into its API for the 4.4 release.
Right.
* QtMobility is creating a second Multimedia API which will be lower
level
than Phonon which will be in Qt 4.6 under a QtMultimedia namespace.
Wrong, you're mixing up 2 things:
* QtMobility is creating a second Multimedia API which they see as replacing
Phonon. It will be on basically the same level as Phonon (though a backend
wrapping Phonon is being considered).
* There is a low-level (direct PCM access) audio API which will be in Qt 4.6
under a QtMultimedia namespace, complementing Phonon (which still doesn't
have a low-level API (one was started on a work branch, but never made it
into trunk, and it only has an ALSA backend, more would be needed for
portability)). The QtMultimedia stuff appears to have backends for all Qt
platforms.
Those 2 sets of classes are separate (though they may (or may not) end up
merged under the QtMultimedia namespace in a future version of Qt).
* Fedora-KDE will be meeting next week with the upstream (kde)
developers
regarding the future of Phonon in KDE.
Not exactly true either.
We will try to gather feedback from upstream over the next week and discuss
the matter again next week in our meeting based on that feedback. (Another
reason why this shouldn't be covered this week, the discussion got postponed
to next week at the earliest.)
* Some Fedora-KDE members (Kevin, Sho_, Rex(?)) believe the API to
be
inferior
It's not just inferior, it's also not ready yet and will be incompatible
with Phonon, so KDE apps will continue using Phonon for the foreseeable
future.
and may end up becoming the main Multimedia API in Qt
That indeed seems to be the case.
as Phonon becomes older and older (via IRC logs)
Phonon itself is actively developed, what we're worried about is that the
copy inside Qt will be bitrotting.
What I don't know:
Well, we don't know for sure either. But as far as I know:
* What does this mean for KDE for KDE now, KDE4.4 (which will be on
Qt
4.6?) and the future of the project in general?
Not much, KDE will just continue using Phonon.
Our worries are about the future of Qt's bundled Phonon (which is the Phonon
we're currently shipping in Rawhide, also because of the circular Qt-
Phonon->Qt dependency due to QtWebKit using Phonon) and of the
Phonon-
GStreamer backend (which is primarily maintained by Qt Software).
* Will KDE apps begin using QtMultimedia (or a KDE derivative) over
Phonon?
No.
* How do Fedora-KDE developers feel about this possible change and
the new API in general? There is, as always, both sides to the issue and I
want to capture both.
My personal opinion: It just reinvents the wheel for no reason and is yet
another incompatible API. This continues the pattern of Qt reinventing
inferior versions of kdelibs functionality, ending what was marketed as the
first success story of KDE-Qt cooperation. We're back to the times of KDE
and Qt containing duplicate functionality because KDE's version was there
first and is better in many ways. :-(
The QtMobility folks claim Phonon is incomplete because it's missing
features X, Y and Z, but when you research things, you find out that X is
already implemented in Phonon trunk which Qt doesn't seem to be interested
in merging, Y is being implemented and Z is planned, but nobody bothered
working on implementing it (so the QtMobility folks could have done it
within Phonon instead of reinventing the wheel). For example, extracting
single frames from a video (useful e.g. for thumbnailing) is one such
"feature X". On the other hand, their stuff isn't even usable yet.
Sorry if I sound ignorant on the subject (I am) and thanks for
helping me
out. This'll be in FWN next week under the (new) KDE beat if I can get a
handle on this issue.
To be honest, I think that if FWN wants to cover KDE stuff, somebody who
follows the discussions on #fedora-kde and knows what they mean will have to
do it. (For example, I believe everything I wrote about Phonon in this mail
was said on #fedora-kde at some point.) Somebody as confused as you are will
just misinform users. :-( Sorry for being blunt…
Kevin Kofler