[MPlayer-users] Containers, GMC, PSNR, and doom9

[The Wanderer]

Alexander Noe' wrote:

> The Wanderer schrieb:
> 
>>> The best way for mplayer to support that would probably be to map
>>> the chunk containing the entire subtitle stream into a
>>> memory-mapped file and run it through a subtitle file parser,
>>> treating it as external file. I guess this best way is not
>>> considered good enough...

<note that he snipped something here>

>> The only reason that it might not be accepted is as a way to say
>> "breaking interleaving like that is not acceptable, get the people
>> who create the tools which mux in such a broken way to split the
>> subtitles up into vaguely appropriate chunks",
> 
> For SSA, this would break seeking, because the SSA headers would be
> in the first chunk, which would go beyond AVI specs. Moving the
> headers somewhere into the stream headers would break VSFilter,
> MediaPlayer Classic, probably Haali Media Splitter.

Since the headers themselves *do* conceptually belong in the stream
headers, that would mean that they have implemented the whole thing
incorrectly.

Incidentally, are you indicating that Media Player Classic is capable of
muxing files in which the subtitles are embedded as a single chunk like
that? I wasn't talking about players - players will adapt, or attempt to
refuse and create a philosophical war, which is acceptable in its own
way - but only about programs which actually *create* the problematic
files. See below.

> Reading the subs at the beginning, creating a memory mapped file, and
> treating the subs as external file would actually not cause any
> issue, at least none I could think off (unless, of course, somewhere
> out there is an OS mplayer is supposed to run on which has no
> memory-mapped files, like MS-DOS :D ).

It would not have any practical implications that I know of, no. The
only possible objections I can think of off the top of my head are a
matter of philosophical principle, which while important is not
necessarily unbreakable in this instance.

In other words: the Right Way to fix this is not for players to
implement support for the mis-muxed subtitles, but for the muxing
programs to implement correct muxing of the subtitles and for players to
then implement support for that. However, it is possible that it might
be acceptable to do things in something other than the Right Way just
this once.

-- 
       The Wanderer

Warning: Simply because I argue an issue does not mean I agree with any
side of it.

Secrecy is the beginning of tyranny.