Does XBMC for Windows use internal or external codecs?

I primarily use my HTPC for h.264 decoding.

I use CoreAVC and Media Player Classic. For the most part, playback is flawless.

With XBMC, I get an ever so slight jitter. I don't know if it's codec issues, video playback software (mplayer?), or maybe because XBMC is running in the background?

I obviously don't know the inner workings of XBMC, but maybe someone can shed some light? Maybe a setting or tweak somewhere?

XBMC for Windows uses the FFmpeg open source codec-suit inside our own in-house developed video-player, (not MPlayer, nor any external codecs).

There is nothing that you can do or tweak unless you are C-programmer who have the skills required to make FFmpeg open source codec-suit code decode H264 faster. Note though many others who does have the skills required are working on optimizing and bettering FFmpeg on a daily bases, ...my guess is by the end of this year XBMC using FFmpeg will be able to decode H264 just as fast as CoreAVC can today.

PS! As a non-programmer the only thing you can do today to get XBMC to decode video faster is buy a faster CPU.

Thanks for all the information.

I know FFmpeg has been out there for a long time now but I didn't know about any recent h.264 developments.

I'll try to live with it before upgrading.

The thing is... If you run ffdshow tryouts (which uses ffmpeg right?) the performance is much better than in XBMC.

So we basically one of the following must be true:

1. The ffdshow tryouts optimize ffmpeg somehow.
2. FFmpeg doesn't work well with OpenGL.
3. The in-house XBMC video player degrades the performance.

Did I forget something?

Please note that I am not trying to bash XBMC, I just want to get some kind of insight where the problem might be. I know I've touched this subject before, but without any responses.
If it is ignored I would feel it's ignorant to "blame" FFmpeg for the performance (given ffdshow gives better performance).

Cheers.

I did a quick search and read a couple posts, but another thing are multi-core CPUs. Is DVDPlayer/XBMC optimized to run on multiple cores?

phunqe Wrote:1. The ffdshow tryouts optimize ffmpeg somehow.
2. FFmpeg doesn't work well with OpenGL.

Both those may very well be true, however I do not think that 3rd is true at all.

Maybe ffdshow disables inloop deblocking for all high-resolution videos? that would give more frames per seconds at the expense of quality, see:
http://forum.xbmc.org/showthread.php?tid=32572
and
http://forum.xbmc.org/showthread.php?tid=33917

Note when reading thos topic-threads that XBMC for Linux, XBMC for Mac, and XBMC for Windows does not use MPlayer, they use DVDPlayer.

room312 Wrote:Is DVDPlayer/XBMC optimized to run on multiple cores?

FFmpeg currently only supports slice-based multi-processor decoding so while it does utililze all cores it does not scale well so I would not call it "optimized". Know that a FFmpeg developer is working on frame-based multi-processor decoding for Google Summer of Code this year and once that gets implemented into FFmpeg later this year that will be much faster on multiple-processor/cores as frame-based multi-processor decoding scales much better.

Hi,
I recently bought myself a new CPU and Mobo to watch 720p mkv vidz. I didn't want to spend to much money so i bought this:

CPU: AMD 64 X2 4800+
Mobo: Asrock Alive NF6g-GLan with onboard GPU Geforce 6150 SE
512 MbRam
Windows XP

I thought this would be enough power to watch HiDef vids smoothly. But here is the strange thing. The videos still have some slight slowdowns. Normal dialogues and action scenes are fine. But viewing big landscapes and tracking shots "Kamerafahrten" are the problem. These are no heavy "hickups" but they are noticeable.

My question is: why does it have those slowdowns? Is it a XBMC problem?
Is the graka to slow?

thanks for any advice,
SimBla

I'm having a similar problem on my HTPC, but I can't get videos to play at all. I've got an AMD Athlon 64 X2 4800 overclocked to just under 3.00Ghz stable. I'm using a Gigabyte GA-MA78GM-S2H using the onboard graphics with an HDMI output.

I'm trying to watch a few different movies in the MKV format, most are 1080p, a few are 720p. I can't get any of them to play, they all say buffering. I leave them to try to buffer for about an hour, and still no go. Is my computer just not fast enough to play them, or is it just a simple issue that I'm missing?

I just recently discovered that XBMC has been ported over to Windows. I have been using Media Portal for several months and this has been working out great.

My question is: why is XBMC being so inflexible with codecs? Media Portal allows you to actually select the codecs you want to use for decoding audio, x.264, DVD playback, etc. I think that this is really important for those of us that want to do tests, optimize, and the like.

Don't you agree that for now, since ffmpeg doesn't seem to handle x264 as well as CoreAVC that we should have the option to switch that? Or, is your justification because it makes things too complicated? Personally I believe that regardless of the setting within the front-end solution, if your codecs are all hosed up, you'll have problems, so why limit users to "hard-coded" codec requirements?

By the way, this isn't a dig at XBMC, I want to try it out for sure. But playing back a 1080p video in XBMC last night, showed me a substantial amount of video stuttering and audio sync problems, whereas the same video in Media Portal plays smoothly...I obviously can't handle playing a video in a new piece of software with playback issues when I can just use the familiar software that plays smoothly...feel me?