Re: [mythtv-users] Playback performance [all platforms]
Greg Estabrooks <[EMAIL PROTECTED]> writes: >> AFAICT, there's no processor-specific optimization in playback at all. >> So if performance is bad on PPC/Darwin, it's probably bad (compared to >> what's possible) on x86/Linux as well. > > The differences is that scalling/display through XV is hardware > accelerated whereas on the PPC it's using Quicktimes ScaleMatrix which > is done in software. According to a Apple Tech I spoke with the other day > that with the right combo of OSX versions and hardware it will be done > in hardware but I didn't get any specifics on what the right combos > are. > >> Ouch, really? Not good news for the MacOS folks. I wonder what about >> the MacOS frontend is sucking so badly? I am running a > > I'd bet money that a large portion of it is the scaling of the video. > If someone with a MAC wants to do research I'm sure a proper solution > could be found, if only so that other MAC frontend users will have > the info when making hardware purchases > >> > So I' can't vouch for possible x86 optimization, but I'm pretty sure >> > the code could be tweaked to run faster on Darwin/PPC. >> >> Can you explain why you are pretty sure of that? > > There is definately better ways to take advantage of the hardware which > isn't being done on the MAC. > > If someone wants to send me one I'd volunteer to work on it :) I'd be happy to; I have one that's presently gathering dust. What's your address (offline, if you prefer)? The more muscle we can put behind Mac development, the better, as far as I'm concerned. -- Dave Abrahams Boost Consulting www.boost-consulting.com ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
> AFAICT, there's no processor-specific optimization in playback at all. > So if performance is bad on PPC/Darwin, it's probably bad (compared to > what's possible) on x86/Linux as well. The differences is that scalling/display through XV is hardware accelerated whereas on the PPC it's using Quicktimes ScaleMatrix which is done in software. According to a Apple Tech I spoke with the other day that with the right combo of OSX versions and hardware it will be done in hardware but I didn't get any specifics on what the right combos are. > Ouch, really? Not good news for the MacOS folks. I wonder what about > the MacOS frontend is sucking so badly? I am running a I'd bet money that a large portion of it is the scaling of the video. If someone with a MAC wants to do research I'm sure a proper solution could be found, if only so that other MAC frontend users will have the info when making hardware purchases > > So I' can't vouch for possible x86 optimization, but I'm pretty sure > > the code could be tweaked to run faster on Darwin/PPC. > > Can you explain why you are pretty sure of that? There is definately better ways to take advantage of the hardware which isn't being done on the MAC. If someone wants to send me one I'd volunteer to work on it :) ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
Jens Baumeister <[EMAIL PROTECTED]> writes: > On 1/9/06, David Abrahams <[EMAIL PROTECTED]> wrote: >> >> I notice that the performance of playback seems to be suboptimal. For >> example, I captured some HDTV video over firewire using MythTV. When >> I try to play it back using the frontend, it is totally unwatchable. >> > [...] >> However, when I use VLC to play the same file, it looks almost >> perfect > [...] >> And if Darwin-specific playback >> code turns out to help, doesn't it indicate that the playback code >> MythTV is using for all other platforms today could be a whole lot >> more efficient? > >>From what I've read, there isn't much PPC or Darwin optimization in > MythTV - at least not in the releases. I don't know about SVN. AFAICT, there's no processor-specific optimization in playback at all. So if performance is bad on PPC/Darwin, it's probably bad (compared to what's possible) on x86/Linux as well. > I use 0.18.1 on an old 550 MHz G4 PowerBook with 768 MB RAM as my > kitchen frontend with nothing else running on it, and it just barely > handles the task. (E.g. it starts to stutter when mythtvosd scrolls > something through the frame.) OTOH my master backend ist a Gentoo > PIII 600 MHz with only 256 MB RAM (I know, I should buy some more...) > which also doubles as my living room frontend and usually has other > stuff (server apps, iPod transcoding, commercial flagging, etc.) > running in the background - yet it feels a lot more responsive than > the OS X frontend and hardly ever stutters. Ouch, really? Not good news for the MacOS folks. I wonder what about the MacOS frontend is sucking so badly? I am running a frontend/backend combo on a 1.42 GHz Mac Mini (admittedly it could stand a RAM upgrade from 512M to 1G, but I don't think that's the issue) and I see a *lot* of beachballs. Maybe I'd be better off buying a cheap linux box, but I really like the "just-works appliance" nature of the Mac for this purpose. Any idea how I can find out what the problem is? I don't imagine profiling will make a huge difference in such a highly threaded application. > I've spent some time setting up setuid permissions and process > priorities on the Linux box, but I don't think I'll manage to squeeze > much more performance out of the OS X frontend doing that. Why not? > So I' can't vouch for possible x86 optimization, but I'm pretty sure > the code could be tweaked to run faster on Darwin/PPC. Can you explain why you are pretty sure of that? Thanks, -- Dave Abrahams Boost Consulting www.boost-consulting.com ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
David Abrahams wrote: I notice that the performance of playback seems to be suboptimal. For example, I captured some HDTV video over firewire using MythTV. When I try to play it back using the frontend, it is totally unwatchable. The action occurs at about half speed because of stuttering and includes frequent pauses of up to a second. I tried tweaking all the obvious settings in the Playback section of the front end's setup screen, to no avail. However, when I use VLC to play the same file, it looks almost perfect, with only barely perceptible jerkiness due, presumably, to the fact that my Mac Mini can't quite keep up with playback. I grepped the MythTV source for CONFIG_DARWIN to find the Darwin-specific playback code, but came up empty. Perhaps we *need* some darwin-specific playback code? And if Darwin-specific playback code turns out to help, doesn't it indicate that the playback code MythTV is using for all other platforms today could be a whole lot more efficient? I believe so. Similar to Linux, software playback is the norm unless other things are used to get hardware acceleration working. On Linux we can use XvMC on some cards to get things to render accelerated in hardware. I would expect that similar features would have to be taken advantage of (which VLC probably already does) to enable the acceleration on the Mac side. Kevin ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
On 1/9/06, David Abrahams <[EMAIL PROTECTED]> wrote: > > I notice that the performance of playback seems to be suboptimal. For > example, I captured some HDTV video over firewire using MythTV. When > I try to play it back using the frontend, it is totally unwatchable. > [...] > However, when I use VLC to play the same file, it looks almost > perfect [...] > And if Darwin-specific playback > code turns out to help, doesn't it indicate that the playback code > MythTV is using for all other platforms today could be a whole lot > more efficient? >From what I've read, there isn't much PPC or Darwin optimization in MythTV - at least not in the releases. I don't know about SVN. I use 0.18.1 on an old 550 MHz G4 PowerBook with 768 MB RAM as my kitchen frontend with nothing else running on it, and it just barely handles the task. (E.g. it starts to stutter when mythtvosd scrolls something through the frame.) OTOH my master backend ist a Gentoo PIII 600 MHz with only 256 MB RAM (I know, I should buy some more...) which also doubles as my living room frontend and usually has other stuff (server apps, iPod transcoding, commercial flagging, etc.) running in the background - yet it feels a lot more responsive than the OS X frontend and hardly ever stutters. I've spent some time setting up setuid permissions and process priorities on the Linux box, but I don't think I'll manage to squeeze much more performance out of the OS X frontend doing that. So I' can't vouch for possible x86 optimization, but I'm pretty sure the code could be tweaked to run faster on Darwin/PPC. Jens ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
David Abrahams wrote: David Abrahams <[EMAIL PROTECTED]> writes: If this is really something that can be fixed by configuration rather than programming, my apologies in advance, but so far I think it's a developer issue. Whoops; I *meant* to send it to the developer's list heck, copy us users. I want to know! ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
Re: [mythtv-users] Playback performance [all platforms]
David Abrahams <[EMAIL PROTECTED]> writes: > If this is really something that can be fixed by configuration rather > than programming, my apologies in advance, but so far I think it's a > developer issue. Whoops; I *meant* to send it to the developer's list! -- Dave Abrahams Boost Consulting www.boost-consulting.com ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
[mythtv-users] Playback performance [all platforms]
I notice that the performance of playback seems to be suboptimal. For example, I captured some HDTV video over firewire using MythTV. When I try to play it back using the frontend, it is totally unwatchable. The action occurs at about half speed because of stuttering and includes frequent pauses of up to a second. I tried tweaking all the obvious settings in the Playback section of the front end's setup screen, to no avail. However, when I use VLC to play the same file, it looks almost perfect, with only barely perceptible jerkiness due, presumably, to the fact that my Mac Mini can't quite keep up with playback. I grepped the MythTV source for CONFIG_DARWIN to find the Darwin-specific playback code, but came up empty. Perhaps we *need* some darwin-specific playback code? And if Darwin-specific playback code turns out to help, doesn't it indicate that the playback code MythTV is using for all other platforms today could be a whole lot more efficient? Also: does all MythTV playback go through NuppelVideoPlayer? If this is really something that can be fixed by configuration rather than programming, my apologies in advance, but so far I think it's a developer issue. -- Dave Abrahams Boost Consulting www.boost-consulting.com ___ mythtv-users mailing list mythtv-users@mythtv.org http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
