revVideoGrabber: stop preview doesn't hide video window

stephen barncard stephenREVOLUTION2 at
Sat Aug 7 12:52:41 EDT 2010

It depends of what you define as 'long'.  I was transferring entire 8mm
tapes at SD DV resolution - 2 hrs - and generating up to 24g files.  I would
get sync issues as big as 10 seconds sometimes. Other times not.

Videograbber could be extremely useful for archiving. Video transfer and
database integrated into one app. An archivist's dream.

The audio issues are puzzling, and indicate an external sort of half-baked.
I suspect that these issues are related to the ambiguity of the audio for
videograbber, especially when the audio panel is used, which seems to make
things worse.

Doesn't anybody test these things before release?

On 7 August 2010 08:35, Ben Rubinstein <benr_mc at> wrote:

> Thanks for the confirmation Richard, I've added a report to RQCC for this
> issue.
> I'm a bit perturbed by the combination of the "The PC side works much
> better than the Mac side" with "runs with adequate stability even for video
> grabs as long as 3-5 minutes".  The latter seems to me to be a doubly low
> standard: "adequate stability" and "as long as...".
> So far my testing (on Mac) with a rig cycling round initialising, setting
> settings, preview, capture (for short capture runs at this point, ie 5
> seconds) and closing the video grabber has captured approx 2,000 clips over
> a nine hour period without evident issues.  Should I infer from your remarks
> that I got lucky?  Is it long grabs (my next set of tests) that is the
> problem?
> Many thanks,
> Ben
> On 06/08/2010 00:38, Richard Miller wrote:
>> Ben,
>> We use the video grabber functions extensively in our software, but only
>> on PC's (where it runs with adequate stability even for video grabs as
>> long as 3-5 minutes). The PC side works much better than the Mac side.
>> The issue you are running into on a Mac is a known bug. You're not doing
>> anything wrong. But I've not found it a problem to use
>> revCloseVIdeoGrabber as often as needed (on Mac or PC side)... because
>> you are right in saying it is the only way to get rid of the preview
>> image on a Mac.
>> Richard Miller
>> On 8/5/10 5:39 PM, Ben Rubinstein wrote:
>>> Docs for revStopPreviewingVideo says:
>>> "Stops showing input from a video camera in the video grabber window."
>>> "Use the revStopPreviewingVideo command to stop showing video input."
>>> "When you stop previewing video, the video grabber window shows a
>>> blank screen."
>>> When I try this (rev 4.0 or later, on MacOS X 10.6) it doesn't show a
>>> blank screen, instead I'm left with a still of the last frame. The
>>> only way to make it go away is to execute revCloseVideoGrabber.
>>> Is this a known bug? Am I doing something wrong? Does anyone else
>>> experience this, or conversely has anyone experience of it working as
>>> documented?
>>> TIA,
>>> Ben
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Stephen Barncard
San Francisco Ca. USA

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