VHS tape "skips or jumps"

[Speedpuppy]

hi, i bought VHS tapes and want to convert, i capture using the ATI card works great but on some tapes (used blockbuster buys) capture is fine but during playback on computer the video "jumps or skips" about every sec...

any ideas

thanks


ps doesnt do this when i capture home video or other videos i purchased just the "former rental ones"

[Mpegman1986]

Clean your VCR. I would recommend getting a dry vcr cleaner. You can pick these up anywhere, Best Buy, Blockbusters, even drug stores like Walgreens.

But word to the wise, rented/pre-viewed tapes will mess up your vcr.

[offline]

Clean your VCR. I would recommend getting a dry vcr cleaner.

Never ever use a dry cleaner unless it is one of those big
commercial ones with the special tape such as the NTI.

[mazinz]

it could also be that you have a video stabilzier option on your vcr (to stop the pic from jumping) if this is on turn, it off. the dazzle dvc2 gives the same problem you describe if you have a vcr that has that option on

[offline]

mazinz has a good point. With some software there is also a VCR mode that if not selected, does what you describe. Are u sure btw that
macrovison copy protection is not an issue? Most rental video releases are
copyprotected in such a way and the result, without a stabliser, is also similar
to what you describe.

[mazinz]

also though macrovision will only make the pic dark to light, it wont make it jump. it sounds more then likely he has a stabilizer option tunred on and if thats not it then i have no idea

[offline]

also though macrovision will only make the pic dark to light, it wont make it jump

You will find that for many people it often causes the picture to jump depending on
the vcr/tv involved - particularly newer VCR's which are designed
to be more sensitive.

It could be the stabilizer, it could even be that a TBC is needed..
without a detailed description or a snapshot of the offending
cap - who knows?

[tmcmvd]

try putting the video thrue a video enhancer...the ones used for decrambling cable tv... they kill the original sync pulse and add a new one...th epicture should remain perfectly still as it comes out.

greetz.

Mike.

[circleking]

How old are these tapes? Some very old VHS rental tapes had a form of copy protection different from macrovision. It reduced the size of the vertical sync pulse which caused the picture to roll & jump when copied to another tape---also caused many TVs to roll too.

Get a TBC if you can afford one. It really helps when capturing from old tapes.

[C-Dub]

I maybe wrong but all these other post seem to think its the vcr and are telling you to clean your vcr, but what I think you mean is that when you try to copy from Old vcr rentals, so it would have nothing to do with VCRS really the issue is macrovision.





So I think the answer you seek lies within

[tmcmvd]

He may be correct...try copying one of the problem tapes to a second tape on another vcr...and see if f*cked up also...in that case..use a microvision filter or try one of the ATI micrivision disableing tricks.

[Speedpuppy]

what is this ati microvision tricks you write about?

i am using an ati all in wonder board to capture (note these are my own videos i have purchased from stores...some are from blockbuster and the like) and want to see if i can store them on disk....

during the capture the preview on the computer is fine...

after capture then i double click to view in media player thats whent its all jumpy...

thanks

[bbb]

Capture from a new VCR. Or, try tweaking the tracking a bit.

[tmcmvd]

Microvision is a analogue copyprotection system. It messes up your VCR when trying to record a copy. Color, Hue and Sync randomly get messed up in random order.

When Played back to a (newer) TV where is no problem due to resistance differences in the input.

This protection must be built into any capture hardware forced so by the film industry.

You can check if that's your problem by copying a small clip to another vcr...you'll notice soon enough when playing back the copy.

This doesn't mean that that is your problem...but it might be.

Greetz.

Mike.

[lpn1160]

borrow the neighbours 10 yr. old VCR, skip the macrovision and your in like flynn

[bbb]

Does the color pulsate from bright to dark? Or does you picture become black and white? If so, then you have Macrovision problems.

But most capture cards don't have a problem with Macrovision. So, this is strange.

[circleking]

Microvision is a analogue copyprotection system. It messes up your VCR when trying to record a copy. Color, Hue and Sync randomly get messed up in random order.

This type of Macrovison periodically inserts very bright pulses into the vertical interval(an area above the visible picture). These pulses trick the VCR's automatic gain control (AGC) into thinking the video level is much higher than it actually is. The AGC then lowers the video level to an artificially low level causing the picture to grow darker. Other annoying side effects of this low level are loss of sync (sync levels are "blacker than black" but when the video level is artificially low some systems can't properly find the sync pulse. This results in a distorted picture)

This form of Macrovision can be defeated several ways.
One is to build what I call a line selector. This device was originally intended to allow the insertion of text or codes into the vertical interval area, but it also removes the macrovision pulses. Hunt the internet for this. Anyone familiar with timing and delay circuits can easily figure out how to build one.
Or you can buy a macro eliminator which also blanks out that area. (These are all over the net and cost anywhere from $25 to $100 U.S.)
You can get a TBC (Time Base Corrector). This device doesn't remove the Macrovision pulses, but lowers them to the correct video level. TBC's also remove another form of Macrovision called "Colour Stripe" which varies the phase of the colour burst signal every few lines to fool the VCR's velocity error correction circuitry.

Television receivers employ different types of AGC circuits and are not as sensitive to these "errors" introduced by Macrovision; so original material displays normally. Except some projectors---notably LCD.