Disappointing MPEG2 decoding

[McBainUK]

From the wiki:

If you have a relatively slow CPU (e.g. a 1.2GHz Celeron), you will probably want to make sure you don’t have ffdshow or dscaler installed, as you don’t have the horse power required for these.

I've been having playback problems for a while now. Tried loads of decoder combinations and still no luck. My question is how can you tell ffdshow weather is installed? And also how can it be removed?

Thanks, Mark

[jksmurf]

Seeing as this is a sticky thread, I thought I'd add a couple of recent issues (with thread links) that have made my GBPVR viewing experience more pleasurable (i.e. read fewer dropped frames, less jerkiness), especially with a low-spec machine. Apologies if this is seen as repeating existing threads, but hopefully it will help other folks without too much of a forum trawl.

1. If you are in the market for a video cards, or need to upgrade or your Video Card, it is recommended (for mainly quality issues) to buy one with both DVXA and Hardware Acceleration (HA). Refer http://forums.nextpvr.com/showthread.php?t=16157 for some current video card info. Note that a Nvidia Geforce FX5200 has DXVA but NOT HA. A Geforce 6200 up has both.
2. Turn off your MVP(s) i.e. put into standby mode if you run TV out or watch GBPVR on your PC. Refer http://forums.nextpvr.com/showthread.php...65&page=3). The MVP requests GBPVR for screen updates every few seconds and as such "steals" a lot of resources from GBPVR if running on the PC or via TV-Out. This is especially noticeable on low spec PC's (e.g. 1.2GHz PIII CPU+512MB RAM).
3. If you use a Geforce and use the Nvidia PureDecoder/Nvidia Driver in combination, ensure you use the correct combo, as newer drivers have been known to not enable hardware acceleration on cards that do have HA. Refer http://forums.nextpvr.com/showthread.php?t=17265 for the "correct" combo! This may change in future driver releases.

k.

[markrb]

I have tried everything in this post more then once with no luck.
I get tearing and some stutter no matter what I try.
Media Player plays everything just fine.
However this isn't the only Front End I have had this very issue with.
Media Portal has the same issue.
I am using external players with Girder for now.
Hopefully someday I can get the internal player to work right, but I am not holding my breath.

[sub]

Have you tried using the Overlay renderer instead of VMR9? This is what Media Player uses.

[markrb]

I do believe I have, but I will try it again tonight when I get home from work.

[Mysteryman]

So to recap - I'm 100% certain that the 6.05.01.0902 quartz.dll placed manually back in safe mode fixed my issues of jerky playback twice now.

I'll add what I learned with quartz.dll.

I was running a completely unpatched WinXP SP1 system with GB-PVR. I added ATI Catalyst drivers for the video card. During that installation it added DirectX 9b full version. Playback was glassey smooth.

I installed DirectX 9c from Windows update and experienced jerky, very poorly deinterlaced output. I installed the 6.05.01.0902 quartz.dll from this thread. Playback returned to glassy smooth.

Once I made sure the system was stable I allowed Windows update to put on the 25 to 30 "critical" updates in wanted. I noticed one of the updates was a security update to DirectX. The jerky bad deinterlaced output returned. I replaced the quartz again with 6.05.01.0902. Most of the jerkiness is gone, all of the bad deinterlacing is gone, but everyr 5-10 seconds I'll lose a couple frames. This is very noticable on new stations where there is a "ticker" or "crawl" on the bottom/top of the screen.

My advice, if you're running your machine behind a hardware firewall (router) and don't web browse or have any other internet activity on your machine, don't MS patch it. The machine runs great without the "fixes". Mine has never run better than pre-patching.

[River_Styx]

I also have problems with stuttering videoplayback.
I have tried a number of things including the quartz.dll trick but to no effect.

When I looked at which processes were utilizing the CPU at the moment of playback, it was the System process. I can't realy see what important things it needs to do at that point in time. No other applications or stuff is going on.

I have found a rather crude workaround for the time being. I let GBPVR start with a high priority instead of normal priority.

Start /high "GBPVR.exe"

Now it is playing fine....
I know it is a bit crude but its working for me....

[daza67]

What's the latest on resolving jittery playback after ff/rr with the dx9c quartz.dll ?

I have tried a number of later quartz.dll's from KB891220 and KB896178. Some are discussed here without success http://forums.snapstream.com/vb/showthread.php?t=26226.

The only solutions that seem to work are:

1. Forcing yuv mixing mode in straight vmr9 mode by setting VMRPreferYUVMixing to true. Note this mode only works with the dx9c quartz.dll. OSD's and some of the f7 apect ratio modes are also disabled by this mode making it pretty useless but you do get very nice low cpu usage playback !

2. Replacing dx9c quartz.dll with the dx9b version, in my case 6.05.01.0902.

Are there other solutions that work out there ?

[kaffeen]

I have been trying many different things to get GBPVR working without video recording and playback problems. Nothing has worked to date, not even the infamous quartz.dll replacement.

I have tried different digital recording software and some of those other solutions do not have the same recording and playback problems I experience with GBPVR (although they have their warts as well). I would prefer to use GBPVR. It is the most feature rich of all the other solutions I have tried and I like this UI the best.

The best video performance on my machine so far is BeyondTV. I do not understand exactly why BeyondTV has the best video playback and recording, maybe it is their proprietary encoding/decoding software???

I do have a dated machine with very little horsepower (I am trying to salvage an older computer for tasks other than mainstream computing). If the other software alternatives, using the same dated hardware, are working better, I feel I should be able to get better performance from GBPVR with some tweaking.

The problems on my older machine combined with the fact that many of the people posting here have some pretty awesome hardware and are still having the same types of issues make me believe that this is not a hardware and/or OS issue.

I am not sure if this is even possible, but does anyone know how I can get GBPVR to use the same settings and configuration as BeyondTV?

[sub]

I do have a dated machine with very little horsepower (I am trying to salvage an older computer for tasks other than mainstream computing). If the other software alternatives, using the same dated hardware, are working better, I feel I should be able to get better performance from GBPVR with some tweaking.

The problems on my older machine combined with the fact that many of the people posting here have some pretty awesome hardware and are still having the same types of issues make me believe that this is not a hardware and/or OS issue.

What spec is your machine? Does it meet the recommended minimum 1GHz PIII class CPU?