Television Capture Problems

[marcus2704]

Hi,

I am having numerous problems capturing from television and hope someone can advise.

I use VirtualDub to capture the TV, the source is a cable box which I am using via composite. I connect this to a Geforce FX 256mb VIVO card.

I am continually dropping frames when I capture. Being in the UK I set frames to 25 (although the average rate is between 12 and 13 despite me setting it to 25) and the resolution to 640 x 480. In the space of 10 seconds Ill get over 100 dropped frames, and the playback of the video isnt that smooth presumeably because its only recording at around 13 fps.

I have a P4 2.6 processor, and 7200 RPM Hard drive. Is there anything I can do to get better capture?

Also, there is a thin, flashing broken line just above the picture image when I record in VirtualDub, is there anything I can do to remove this - cropping seems to make no difference.

Any help would be greatly appreciated.

[willy_annand]

Hi Marcus, I am in Canada so can only speak about my experiences with NTSC.

NTSC is 29.97fps, I have an AMD 2000+ machine with 316MB RAM and a 40GB HD dedicated to vid caps.

I could not get anywhere with VDub's capture program, continually dropping frames as well.

I got a copy of AVI_IO and had no problem. The only task I do before vid capping is to defrag my HD. Defragging the HD will help your capture program with disk writes. Maybe try that first, if you still drop frames try AVI_IO.

Hope this helps.

[marcus2704]

Hi,

Still no joy Im afraid, in the space of 10 seconds using AVI_IO I had over 100 dropped frames. I have also since upgraded my Hard Drive to a 7200 Serial ATA disk. Any other ideas how I can get round this problem?

Regards

*edit I did just get a capture with no frame drops. However this was without audio enabled in AVI_IO. Perhaps Im getting closer to the answer.. Its set to PCM audio as this is the only format the application supports.

[willy_annand]

Here are some things to think about

Which OS are you using?
I use WinXp, seems to handle vid caps better.

Is there alot going on in the background?
I used to forget to turn off such things as ICQ, MSN, Yahoo, whatever.

If you are using WinXp, call up the task manager and click the "Performance" tab, see how much CPU time and memory are being used before you launch your capture program.

Check and see if the VIVO card has a newer driver. I know that NVidia just released new drivers at the end of May, they are at version 44.03 now.

Check defragmentaion levels on your capture drive.
I usually run Speed Disk before a vid capture anyway, just to be sure.

[Solarjetman]

You could disable your virus checker if you have one. Some checkers will scan newly created files and possibly cause the dropped frames. Though your CPU is nearly twice as fast as mine and I can capture with mine turned on (but I use different capture hardware so keep that in mind).

Also, a lot of programs (I am not sure with AVI_IO and Vdub as I don't capture with them) drop several frames the first few seconds. Studio 8 takes about 3 seconds to start after you hit record for example. Is this where your 100 frames are from, or are they spread out? It might just take the capture program a few seconds (i.e. about 100 frames) to get into gear.

A SATA hard drive should be plenty fast, but if you really think it is a hard drive speed issue, try out a RAID-0 array. That will almost double the speed, but it would be expensive with SATA I think.

[Heavensent]

try updating your soundcard drivers

[D_Knife]

capping 640x480 is a NTSC video size
If you are capturing 25fps then you probably should be using a PAL size
this may be the cause of the problem
try switching to some thing small to test and work your way up from there.
start at 352x288 25fps and see if you can cap all frames without dropping

Then start going up in cap res until you get to 704x576 (full screen pal)

also you didn't mention which codec you are using

[marcus2704]

Thanks for the replies.

I am using a Windows XP operating system. I have onboard sound and have disabled virus checker. It drops frames right from the start, as a rough estimate I get 1 dropped frame for every 3. The frames dont seem to drop when I disable capture of audio however and AVI_IO. As soon as I capture sound the frames drop again. Using TMPGEnc I have never been able to capture without dropping frames. The performance when I capture is low, only about 10-15% of CPU usage. Ill defrag the drive and try again, and let you know.

Regards

[filipdebie]

Hi,
I only have a PII 466Mhz machine and I capture a PAL 352x576 AVI at 25 fps with avi_io and the Picvideo MJPEG compression at quality 19.
First I have to close all programs I don't need and I capture "blind" : no overlay and no preview. I only have 3 or 4 dropped frames an hour.
The quality of TV signal is also very important.
I have a Hauppauge wintv pci but I use the tuner of a videorecorder which I connect to the video in of my Hauppauge.
This method gives me the best results.
With TMPGENC I make CVD or VCD's.

[TBoneit]

This may sound stupid, But

Try updating your sound drivers, if that doesn't help then...

Disable your built-in sound.
Borrow something like a soundblaster live or better

Try again.

It could be that your sound card is using to much cpu or has driver issues.

C. Good Luck

[Craig Tucker]

It does seem from what has been said in this thread that it is the onboard sound which is causing the problems. Vdub does drop frames to compensate for the mismatch between soundcard and vid card clock rates. If there is something wrong with your onboard sound this could account for the dropped frames. Like others have said make sure you have the latest drivers. Do you have lock video to audio stream selected, if so deselect it.

[fingernailX]

If you are running XP then you have a DirectShow only OS and VirtualDub and AVIO are vfw capture progs. This forces the use of the vfwwdm.dll which is a bottleneck. Use amcap or (iuvcr as i do) for low cpu drain and low dropped frames.

[Craig Tucker]

Should not be a problem though, I use vdub with xp and only drop 1 or 2 frames every 4 or 5 mins capturing at 720x576 with huffy.

[menace]

I too had that problem (ECS k7S5A motherboard) used the onboard sound and problems with everything not just capture--got an el-cheapo soundcard and voila. Although AVI_IO has consistently performed better for me than virtualdub. If you do get a new soundcard--learn from my mistake and get a decent one that supports 5.1 capture or other slick audio features. 8)

[marcus2704]

I tried out my Aureal Vortex card, and still got exactly the same problem with dropped frames. Not really sure where to go now, my PC must surely be up to spec to capture composite video, maybe its a configuration issue that Ive overlooked. I drop over 30% of frames continually, irrespective of the resolution. Ive defragged the HD and its made no difference. Crossing AI_IO and VirtualDub off the list, are there any other capture applications you can recommend to me?

[Craig Tucker]

Give iuVCR a try which is a WDM capture program.

[marcus2704]

Worked a treat!

No frame loss, and the positioning of the capture on the screen is far better than VirtualDub and AVI_IO for me. Can someone tell me the optimal setting for PAL in terms of resolution - I know the frames needs to be set to 25 but am unsure of the best resolution to use.

Getting there...Thanks!

[Craig Tucker]

See what is VCD, SVCD and DVD at the top left of the page, it gives all the resolutions there.