[MPlayer-users] Strange behaviour of latest mplayer when seeking

[Reimar Döffinger]

On 9 Apr 2011, at 18:18, Vladimir Mosgalin <mosgalin at VM10124.spb.edu> wrote:
> Hi Reimar Döffinger!
> 
> On 2011.04.09 at 16:33:39 +0200, Reimar Döffinger wrote next:
> 
>> If you have more than one core/CPU it now _definitely_ helps.
>> Though number cores/CPUs + 1 probably is a better value.
>> Previously it would only help with some H.264 streams.
>> The disadvantage is that is causes issues with DR,
>> which also means a small slowdown on one core/CPU systems
>> (in addition to the multithreading overhead in general).
> 
> Well, sadly, multithreading doesn't allow mplayer to do filtering in
> multiple threads still; after last upgrade I could play any stream on
> single core (well haven't tried higher than 1080p / 30fps), but
> performing nearly any kind of filtering on 1080p is still impossible
> (and even heavy filtering on 720p).
> What saves is that most HD streams don't need any filtering, but slight
> sharping can help some of these; so far, unsharp filter + most of 1080p
> content is no go, as mplayer can't utilize more than one core for that.

Well, first multithreading does help: it allows the decoding to be moved to a different CPU.
So as long as the filter itself doesn't need more than 100% of one CPU it should work fine single-threaded.
Secondly: -vo gl can do sharpening on the GPU. I think it uses a much simpler algorithm than unsharp and I haven't had any feedback on it so I don't know if it works as replacement but it might be worth a try.