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Theophilus

Restarts Capture When Monitor Connectivity Is Interrupted

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Others have complained about capture files ending up truncated, unexpectedly shortened. There are probably multiple contributing factors, but I have found one unusual one: monitor connectivity.

 

I have a Windows 7 HP Pavilion PC running Easy VHS to DVD 3 Plus Build 301B91B, and the PC monitor is shared with another PC using a KVM switch. I have found that if I start a capture of a VHS tape, then switch to my other PC to get some work done, when I switch back, the application will *restart* the capture without any error message or notification.

 

When this happens, the "Recording..." field that shows how long the capture has been running is still counting up; it does *not* freeze or reset or anything. But when I check the Properties on the output file, it shows that it suddenly has jumped back to a much smaller size, and if I click on the button to stop the recording, the resulting file is only as long as the time since I switched back to that PC. That is, the file is just the last few minutes of the capture.

 

I know others have seen issues with the application stopping early (with or without error messages) and ending up with truncated files representing the *beginning* of the capture, perhaps because of tape drop-outs. This is something else, obviously. I guess the application is sensitive to the PC's graphics card or video driver in some fashion. This bug is easy to replicate. The size of the capture is irrelevant; if I do a capture and leave the application running on the screen (without switching my KVM), the app always faithfully captures a full two-hour VHS tape with no issues, even ones with a lot of noise.

 

Most people do not use a KVM, probably, but I suspect the same sort of problem could be caused by an intermittent monitor connection, or maybe even by turning off the monitor. I have not tried that yet.

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You are using the same PC to capture and simultaneously work on and don't expect trouble :huh::wacko::huh:

 

IT doesn't have anything to do with the monitors or KVM.

 

Start a capture in the morning with you get up - DON'T fiddle with the PC and see where it is when you leave the house.

 

Also be curious about your PC Specs (Win-Pause, what is under 'System')

Edited by Jim_Hardin

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I guess I wasn't clear, Jim :-) I have two PC's on a KVM to let me switch the monitor/keyboard/mouse between them. I work on the "other" PC, not on the one that is capturing. And, yes, if I just leave the capturing PC running (without switching the monitor away from it), it reliably and consistently captures entire tapes, no need to break it up into smaller capture sessions.

 

But it is indeed quite a repeatable bug; if I switch the monitor away from the capturing PC, then switch it back (a second or an hour later, no difference), the capture quietly restarts the capture-file. No indication in the application at all. Very strange :-) And the capturing PC is not multitasking with anything else. The capturing PC is an Intel Core i5-2400 @ 3.1 Ghz, 8 Gigs of RAM, 64 bit OS.

Edited by Theophilus

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Wow, It almost sound like it is doing a screen capture and when you switch away, the "capture screen" is stopped.

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Theophilus, thank for the info.

 

You have a very non-typical setup and no one has mentioned this in the 8 years it has been out. I think that is an indication of how uncommon the KVM setup is used rather than any reflection of you equipment ;)

 

We have seen when someone 'locks' their PC that capture stops. I want to PM you a test to make so look in the upper right for the indication of a message.

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Thanks, Jim. I will give that test a try.

 

Incidentally, I have reproduced the issue *without the KVM*. The bug happens simply by disconnecting the monitor briefly. I start the capture, and let it run for a few minutes until the capture file shows that it is about 100 Mb in size. Then I briefly pull my monitor's HDMI connector out of the PC and re-insert it. When I check the capture file, it has dropped back to a few Mb in size. The application still shows "Recording..." and a duration of a few minutes as if nothing unusual has occurred; but when I click the button to finish the capture, the top of the screen shows that the captured file length is only ten seconds long or so. The file is indeed that long and contains just the last several seconds of content.

 

Turning the monitor off and on does *not* seem to cause this behavior, thankfully. The monitor circuitry probably keeps the HDMI interface terminated enough, whereas a KVM treats the HDMI connection much the same as manually pulling the cable as I have just done. I suspect the application relies on the existing video drivers to perform some of the processing/decoding under the covers, and those drivers hiccup when the main video connection is interrupted. That sounds like the kind of bug that will never be fixed, because it might require rethinking how the application gets the video processing job done. Annoying for KVM users, of course, since it'd be convenient to run captures on one machine while we're doing something substantive on another :-)

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Does your switch switch the USB?

 

No it is only the Monitor that seems to do it... He also tried unplugging the Monitor after the capture started and got the same results :(

 

I haven't tried it but given the rare nature of a KVM switch and 2 computers, I don't think it needs a lot of my attention :D

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