[FFmpeg-devel] XVMC Deathmatch
Ivan Kalvachev
ikalvachev
Sun Feb 15 02:44:20 CET 2009
On 2/15/09, Michael Niedermayer <michaelni at gmx.at> wrote:
> On Sun, Feb 15, 2009 at 02:34:59AM +0200, Ivan Kalvachev wrote:
>> On 2/15/09, Diego Biurrun <diego at biurrun.de> wrote:
>> > On Sun, Feb 15, 2009 at 01:01:36AM +0100, Diego Biurrun wrote:
>> >> On Sun, Feb 15, 2009 at 01:56:49AM +0200, Ivan Kalvachev wrote:
>> >> > On 2/15/09, Diego Biurrun <diego at biurrun.de> wrote:
>> >> > > On Sun, Feb 15, 2009 at 12:29:18AM +0100, Michael Niedermayer
>> >> > > wrote:
>> >> > >> On Sat, Feb 14, 2009 at 11:40:35PM +0100, Diego Biurrun wrote:
>> >> > >> > On Sat, Feb 14, 2009 at 11:30:02PM +0100, Michael Niedermayer
>> >> > >> > wrote:
>> >> > >> > > On Sat, Feb 14, 2009 at 10:38:39PM +0100, Diego Biurrun wrote:
>> >> > >> > > > On Sat, Feb 14, 2009 at 04:53:01PM +0100, Michael
>> >> > >> > > > Niedermayer
>> >> > >> > > > wrote:
>> >> > >> > > > >
>> >> > >> > > > > > //these are not changed by the decoder!
>> >> > >> > > > > > int magic;
>> >> > >> > > > >
>> >> > >> > > > > 3 points
>> >> > >> > > > > find and get rid of or rename fields to "ununsed123" all
>> >> > >> > > > > unused
>> >> > >> > > > > fields in this
>> >> > >> > > > > struct, dont break ABI!
>> >> > >> > > >
>> >> > >> > > > All fields are used either in FFmpeg or MPlayer.
>> >> > >> > > >
>> >> > >> > > > The following are unused in FFmpeg:
>> >> > >> > > >
>> >> > >> > > > int mc_type;
>> >> > >> > > > int chroma_format;
>> >> > >> > > > unsigned int display_flags;
>> >> > >> > > > int state;
>> >> > >> > > > void* p_osd_target_surface_render;
>> >> > >> > > >
>> >> > >> > > > But they are all used in libvo/vo_xvmc.c in MPlayer as can
>> >> > >> > > > be
>> >> > >> > > > seen
>> >> > >> > > > by
>> >> > >> > > > trying to compile against an xvmc.h without those fields:
>> >> > >> > > >
>> >> > >> > > > libvo/vo_xvmc.c: In function 'xvmc_draw_image':
>> >> > >> > > > libvo/vo_xvmc.c:378: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'state'
>> >> > >> > > > libvo/vo_xvmc.c: In function 'config':
>> >> > >> > > > libvo/vo_xvmc.c:536: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'mc_type'
>> >> > >> > > > libvo/vo_xvmc.c:538: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'chroma_format'
>> >> > >> > > > libvo/vo_xvmc.c: In function 'draw_osd':
>> >> > >> > > > libvo/vo_xvmc.c:899: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'display_flags'
>> >> > >> > > > libvo/vo_xvmc.c:899: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'display_flags'
>> >> > >> > > > libvo/vo_xvmc.c:902: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'state'
>> >> > >> > > > libvo/vo_xvmc.c:903: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'state'
>> >> > >> > > > libvo/vo_xvmc.c:904: error: 'struct xvmc_render_state' has
>> >> > >> > > > no
>> >> > >> > > > member
>> >> > >> > > > named 'p_osd_target_surface_render'
>> >> > >> > > > [...]
>> >> > >> > > >
>> >> > >> > > > Does research give points? :)
>> >> > >> > >
>> >> > >> > > no, you have to remove or rename these fields to unused* to
>> >> > >> > > get
>> >> > >> > > the
>> >> > >> > > points.
>> >> > >> >
>> >> > >> > Well, I did do
>> >> > >> >
>> >> > >> > int mc_type;
>> >> > >> >
>> >> > >> > -->
>> >> > >> >
>> >> > >> > int unused1;
>> >> > >> >
>> >> > >> > and FFmpeg compiles fine afterwards, but when I put that xvmc.h
>> >> > >> > in
>> >> > >> > my
>> >> > >> > MPlayer tree, I get the above compilation failure.
>> >> > >> >
>> >> > >> > Thus my conclusion is that the field is not, as you claim,
>> >> > >> > unused.
>> >> > >> > Am I missing something?
>> >> > >> >
>> >> > >> > > am i allowed to give tips on how to solve such things?
>> >> > >> >
>> >> > >> > This will likely result in more fixes :)
>> >> > >>
>> >> > >> well
>> >> > >> first as was said the header was not public thus no rename in the
>> >> > >> header
>> >> > >> really could break an external APP, removial of a field of course
>> >> > >> could
>> >> > >> so renaming these to unused123 and placing them under #if
>> >> > >> no_major_bump_yet
>> >> > >> should not break anything (in theory)
>> >> > >
>> >> > > I had all the fields I mentioned above under
>> >> > >
>> >> > > #if LIBAVCODEC_VERSION_MAJOR < 53
>> >> > >
>> >> > >> yes it means mplayer has to be updated before the next major bump
>> >> > >> and
>> >> > >> before it could use our installed header instead of its private
>> >> > >> copy
>> >> > >>
>> >> > >> but thats mplayers problem to say it harshly ...
>> >> > >
>> >> > > Well...
>> >> > > Ivan designed this incestuously. It's kind of hard to tell if this
>> >> > > is
>> >> > > a
>> >> > > public or a private header...
>> >> >
>> >> > Well, don't tell me I didn't had reasons to hold your
>> >> > plans on making it public header.
>> >>
>> >> You held that plan back for many years. Without this deathmatch, you
>> >> would not have made those changes to MPlayer.
>> >>
>> >> > > I suggest that we assume it is becoming a public header just now
>> >> > > and
>> >> > > thus
>> >> > > now that Ivan updated MPlayer to not use them anymore, the
>> >> > > following
>> >> > > two
>> >> > > fields could be safely be removed:
>> >> > >
>> >> > > int mc_type;
>> >> > > int chroma_format;
>> >> > >
>> >> > > OK to remove them?
>> >> >
>> >> > You were the one who insisted on installing it.
>> >> > Deal with the consequences.
>> >>
>> >> I take that as a "I don't care", which I will now interpret to mean I
>> >> have a free ticket to go ahead.
>> >
>> > Note to Michael: I know this breaks ABI and API. I'm operating under
>> > the
>> > assumption that the API is still in flux and the only user is MPlayer,
>> > which has already been updated.
>> >
>> > So don't go subtracting points from me :)
>>
>> Michael,
>> Is breaking ABI OK for you.
>> I can make some general changes if this is so!
>
> i dont give a damn about the lavc XVMC ABI, if it can be improved by
> breaking
> ABI ...
> just think about what you will tell the distro maintainers when their
> lavc suddenly starts acting up with mplayer and xvmc ... with some versions
> being combined ... maybe one should tell them so that they can take some
> precautions
AFAIK
you can't use xvmc with shared libavcodecs,
unless you do really durty tricks.
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