[MPlayer-dev-eng] [PATCH] Stereo3D: Row-Interleave Output Support

[Steaphan Greene]

On 06/21/2011 01:55 PM, Reimar Döffinger wrote:
> On Tue, Jun 21, 2011 at 01:41:06PM -0400, Steaphan Greene wrote:
>> On 06/19/2011 11:32 AM, Steaphan Greene wrote:
>>> I've attached a patch (to current SVN, r33659) which this fixes this
>>> problem, corrects the new man page note, and also includes my earlier
>>> patch to increase the maximum aspect ratio to the -aspect option to 4.0
>>> (which is required to use this to play the many side-by-side movies
>>> which are half-width).
>>
>> I've attached an updated patch for current SVN, r33688.  The aspect
>> ratio limit part is now obsolete, but the rest is unchanged.
> 
> As for the man-page: I also replaced "it's" with "it is". Short forms
> should not be used in the documentation.

I see.  Sounds good.  Thanks.


> I also applied the other change,

Great, thanks!


> ...though I was wondering if changing
> the first memcpy_pic is a good idea.
> I think the way it is currently it should give better performance, so
> I did change it, but that might not necessarily be the case.

Well, memcpy_pic is just a macro that calls memcpy_pic2 with a zero at
the end.  In all cases other than these new interleave outputs, that's
still exactly what it will do.

In the interleaved-output cases, it will now pass a 1 so it knows it
can't "optimize" these copies into a single copy.  It might sound faster
to do it as one copy the first time, except that this copy will copy all
rows (even those which are about to be overwritten), which would roughly
double the amount of data copied for the first copy, compared to my
version, which skips the copying of these rows.

So, I would expect calling memcpy_pic for the first copy would actually
end up being slower than the version you just committed, despite the
additional instructions required to skip these unused rows.

Dos that sound right to you?

-- 
Steaphan Greene <sgreene at cs.binghamton.edu>
Lecturer, Computer Science, Binghamton University
GPG public key: http://www.cs.binghamton.edu/~sgreene/gpg.key.txt