too many dropped frames in virtualdub

[anr]

hi all,

my system is a duron 800, mb ASUS 7V-E, 256MB RAM 133, nvidia geforce 2mx, and 2x20GB harddisks, and my capture card is a AVER TV98, i am using the WDM drivers from IULAB

i think my system is fast enought to capture from VHS without too much dropped frames?

i am not using any filters or audio codecs, just PCM sound, so the only intesive calcs are made by the video codec?

well, i use HUFFYUV as codec, or MJPEG, set up virtualdub to capture to 352x288 PAL 25fps, audio to 44khz 16bit mono, hide on capture, etc ... i've read all guides, and i think is ok optimized (hardisks has dma, using lastest via4in1 drivers, etc, etc...)

i got nearly 60%-65% cpu usage, but i got so many droped frames, nearly 4 every 10 frames (yes,nearly 50%)

the fps count is always around 13-14-15, not 25 fps

i forgot to say that if i capture in IUVCR program, i got 0 dropped frames,can i be confident with this result? i think i see jerky frames in the video output, also the fps here is around 13-14

changing from HuffYUV to MJPEG don't seems to fix anything, i've also tried the WDM drivers from that page in sourceforge without results

any ideas? please help! :D

thanks guys,
anr

[Pojken Purken]

You don't mention what OS you're using. WDM drivers suggest it's W2K or XP. Although some people claim they're successful in capturing with WDM drivers on these systems there are still major performance problems. I'll advice you to have a separate W98 boot partition for your capture tasks. Your system is fine otherwise.

Regards
PP

[anr]

thanks for your answer,

yes i forgot to mention that my system is running W98 SE, pretty fast and stable for capturing i've read

the only thing i've not tested so far it's to capture using the old VFW drivers (date 1999) from AVER Media,

do you think is worth the effort?

any suggestion about that 13-14 fps limit? this thing it's driving me mad, i've been trying to fix it for 1 month now

thanks again,
anr

[Koepi]

That sounds really weird.

Did you try using YUV colour space (YUV2 or YUVU(?))?
I get many dropped frames when using too high quality on MJPEG. It gets better when setting it (depending on which codec you use) i.e. 70% quality - or PicVideo 16-17 qual, 4/1/1 subsampling seems to be a little faster as well.
I get 1 dropped frame every ~3 minutes in win2k (using the drivers from btwincap.sf.net) due to sync issues with the soundcard, but those aren't noticable afterwoods.

Just an idea,

regards,
Koepi

[anr]

hi koepi,

yes, i am using YUV color space, YUY2, also i've used HUFFYUV and picvideo's mjpeg with quality setting from 14 to 18

it's YUY2 ok?, other formats i can use are RGB24, RGB555 (i've read they are slower because codecs have to convert to yuv color space) and YVU9 and YV12

i've made other tests, AMCAP and IUVCR tells me no dropped frames, but i am sure they are losting them, because of jerky video, flycap and virtualdub are at least sincere :D because they tell me the truth...

i've read that bad sound cards could be the cause, because virtual dub has to stop for sync the sound, but so many times?

i am using the integrated sound card in my motherboard, a cheap AC97 chip, and i am capturing directly from the mic input of the motherboard

regards,
anr

[Pojken Purken]

Originally posted by anr
the only thing i've not tested so far it's to capture using the old VFW drivers (date 1999) from AVER Media,

do you think is worth the effort?


I defintively think that's worth a try!
/PP