Kodi Community Forum - PPC and h.264

Hi ho.

First off, thanks to davilla for all his hard work and responding to issues here in the forum. Overall, I'm overjoyed with how XBMC works on my old PPC mac mini (1.42 GHz).

However any h.264 video is.. borderline. Regular mpeg-4 (ffmpeg/DivX/Xvid) works fairly well, but anything with h.264 throws the CPU usage upwards of 95% CPU usage. The seems to result in low framerates (16-24fps on an NTSC film video), jerky framerates, etc, etc..

I've poked and prodded a bit, and here are the things that I've noticed:

The Mini only supports OpenGL 1.3 with the ARB extensions. Not sure if this is a factor.

Browsing through the menus, CPU usage is around 60-70%, at about 65fps, which seems a bit excessive.

When pausing an h.264 video, system CPU usage remains above 95%, which also seems odd.

While playing: dcpu=1%, acpu=4%, vcpu=~40%, CPU=95%

I can put up my debug xbmc.log file if necessary, but I don't see anything TOO interesting in there, beyond all the swscaler complaints about nonaccellerated colorspaces.

The other main players on the system (VLC, mplayer, and Quicktime) play at the same resolutions and fullscreen, at about 65-80% cpu, still a bit tight, but with enough headroom to avoid dropped frames.

So I guess I have two questions. The the rest of XBMC add much cpu overhead to the dvdplayer app while it is active, and could it be dragging it down a bit? And second, is there any optimizations in the ffmpeg compilation options in XBMC that could help this out? I've downloaded the recent trunk, but haven't attempted to compile it yet to poke at it harder. I thought it might be easier to ask first.

thanks,

jf

Ulm01 Wrote:The Mini only supports OpenGL 1.3 with the ARB extensions. Not sure if this is a factor.

So I guess I have two questions. The the rest of XBMC add much cpu overhead to the dvdplayer app while it is active, and could it be dragging it down a bit? And second, is there any optimizations in the ffmpeg compilation options in XBMC that could help this out? I've downloaded the recent trunk, but haven't attempted to compile it yet to poke at it harder. I thought it might be easier to ask first.

1) OpenGL 1.3 -> that means that the mac mini can only use software render method.

2) ffmpeg is already compiled with AltiVec optimizations enabled, so I don't think we can do much more on that side...

My PowerBook G4 has the same CPU as my mac mini (1.25GHz), but it has an ATI Radeon 9600 (9200 on the mac mini). It can use ARB shaders.
I have no problem watching h.264 video with youtube plugin.
CPU is "only" around 50%.

So the main problem with the mac mini is that it only supports software renderer. That requires a lot of CPU... that it doesn't really have...

I would love if my mac mini could do better, but it's an old piece of hardware... Might have to upgrade one day Smile

Beenje Wrote:So the main problem with the mac mini is that it only supports software renderer. That requires a lot of CPU... that it doesn't really have...

I would love if my mac mini could do better, but it's an old piece of hardware... Might have to upgrade one day

Too bad I don't have the programming chops to rip out the 'macos' render target from VLC or mplayer and add it. Oh well. I can use the external player function and get mplayer to play anything too troublesome.

thanks,

ulm