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codeguru
5th September 2006, 12:42
Hi! I have a special question about CPU load and framedrops

My system:
Core2 Duo E6600 with 2,4 GHz
runs also stable in 3 GHz with fsb333
Gigabyte 965 Board, F2 Bios
2 GB of corsair DDR667 memory
Guillemot Maxitv with BT878
Intel HD Audio
Ati Radeon X850
XP SP2
BT Wincap drivers / Guillemot Maxitv drivers for W2k
PAL, 720x576 YUY2
1x Raptor 36 Gb, 2x WD SATA 320 GB Raid Edition
Capturing software: Virtualdub 1.6.15 and VirtualVCR

So far - bandwith enough, CPU enough for everything, I thaught.

On older systems I have seen that capturing and on-the-fly encoding will cause audio sync loss or heavy framedrops if cpu load reaches 100% - the reason was 'too many pixels for this poor CPU'.

But now I have this dualcore system that could also run on 3 GHz, stable, but the CPU load doesn't reach barely more than 50% on one CPU before framedrops/inserts are occuring if the encoder options are not on 'average balanced' or 'fast'. encoding huffyuv raw material from harddisk shows that the system could make more than 35-40 fps (2,4 GHz) in fullscreen with the same encoding settings, but it makes 24-25 fps in 2,4 GHz and below 30 fps in 3 GHz when capturing.

So why doesn't Divx (5 or 6) consume all of the CPU speed?
And why I have framedrops although there's enough CPU?
Theoretically DivX could use one CPU at 100% (and I have seen that on some single CPU systems) and the Version 6 does some multithreading that uses at least 30% of the second CPU when encoding ofline.

Awatef
6th September 2006, 13:53
Has probably something to do with the capture driver.
Those new WDM drivers are no good compared to old VfW ones (that don't exist anymore?!)
Anyway, try capturing with DScaler, it may work better.

codeguru
8th September 2006, 13:50
in Vdub I could choose the WDM and the direct access to the capture card.... no change.

Using the Btwincap reduced the framedrops with bad material and enabled custom resolutions they don't work with the guillemot W2k drivers.

I try out the Dscaler this weekend, and will do also a foobar thing - installing Windows 2000 and see if things getting better. Nothing I do require really XP :-)