Timeshift channel change 7-15 seconds!

[sgilani]

GBPVR is running great and display is smooth as silk... but changing channels in Timeshift mode takes a looong time, usually between 7 and 15 seconds! My setup is:

Athlon XP 2500+, 512MB PC3200 ram, PVR-150, nVidia FX5200 with the PureVideo decoders.

From looking at the gbpvr-native logs, it seems to take about 6 seconds between "About to switch files" and "After file switch", but I'm not sure where to go from there. (logs attached)

Can anyone help or give advice? Thanks!

[sub]

I've never really worked out why some machine take a very long time between "About to switch files" and "After file switch". There is only two or three lines of GB-PVR code between these two points, none of which are directly causing this delay. The delays seems to happen somewhere inside directshow.

It also seems to vary on subsequent runs. I see one of yours taking six seconds, but the next one taking very little time.


17:02:20.109 VERBOSE About to switch files
17:02:26.578 VERBOSE After file switch

...

17:15:29.671 VERBOSE About to switch files
17:15:29.703 VERBOSE After file switch


On my machine I fairly consistantly about 3 seconds.

[sgilani]

Yeah, I purposely put in that "quick" one in case you could see some pattern or something.. 90% of the time it takes about 10 seconds, for some reason it only took a second or two that one time.. but never before then or after.

Could the live tv pre-play delay setting affect this? it's on 500ms right now..

I'll keep trying different things and see what happens, but I'm just stumped on this problem.

[sub]

Could the live tv pre-play delay setting affect this? it's on 500ms right now..

No, I dont think so. I'm guessing its more related to the buffering demands of the video decoder or something else strange, meaning directshow cant switch files until some data is finished processing or something like that. I dont know - I'm just guessing really.

[sgilani]

ah, gotcha.. I'll play with different decoders and the like and report back if anything changed..

[sgilani]

Ok, I switched over to DScaler decoders as a test, and now the delay of file switching is gone, but it's still taking around 7 seconds to switch, even though from the logs it doesn't seem so... i've attached the new log.

[sub]

Can you post a matching gbpvr.exe.log and gbpvr.exe-native.log?

[sgilani]

whoops, sorry bout that

[sub]

I'm not really sure. Going by the logs, it looks like it should be taking two or three seconds.

[sgilani]

yep, sure does.. it is certainly faster with DScaler, but the problem is I only get good playback with PureVideo with its Smart deinterlacing; otherwise I get a very weird stutter, sort of like 3:2 pulldown judder.

Perhaps PureVideo using DXVA acceleration could be causing some of this?