[MPlayer-dev-eng] MNG support for MPlayer

[Stefan Schuermans]

compn wrote:
> On Mon, 15 Sep 2008 11:42:06 +0200, Stefan Schuermans wrote:
>> MNG animations do not seem to be supported by MPlayer 1.0rc2. Because I
>> wanted to play back MNG animations using MPlayer, I tried to implement a
>> demuxer in libmpdemux using libmng 1.0.9 (on Debian etch).
>>
>> It worked out and I've been able to play the MNG animations using the
>> new demuxer. Perhaps the code is useful for other people, so I'm sending
>> the patchfile.
> 
> nice work. please wait for our demuxer maintainer.
> libmpdemux is being slowly obsoleted, but rxt said he wouldnt
> reject demuxers that passed review.
>
> nico reviewed your patch in july when you first sent it.
> http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/2008-July/058145.html
> could you address those small issues?

Oh, I wasn't aware the patch actually made it to the list. I recevied a 
notification in reply that my mail was on hold for approval and did not 
hear anything else. So today, I decided to join the list and try again. 
Sorry for posting it twice.

I'll fix most of those issues. However, I'm not sure what to do aginst
the comment to demux_mng_refresh() and the static framerate yet.

The demux_mng_refresh() function may be called for parts of the display 
only by libmng. So it might happen that there are two invocatiosn of 
demug_mng_refresh() for the same frame, once for the upper half and once 
for the lower half. However, if only a part of the image changes between 
two frames, it is also possible that debug_mng_refresh() is only called 
for this part and the rest of the frame has to use the data from the 
last frame.

MNG has a variable framerate with the time of a frame ranging from 1ms 
to multiple seconds. I don't know how to change the framerate MPlayer 
uses in the middle of playing.

Both issues boil down to the same "problem": libmng wants to decide when 
to take an action regarding the display and MPlayer also wants to decide 
whan to take such an action (i.e. display the next frame) by calling 
demux_mng_fill_buffer( ). At least, I've understood it this way...

> can you please diff this against current svn ?

Yes, I'll try to do that.

> missing standard mplayer license header (please copy and paste from any
> mplayer file).

Okay.

Regards,
Stefan