Name: revInitializeVideoGrabber

Type: command

Syntax: revInitializeVideoGrabber <parentStack>, <videoMethod>, <grabberRect>

Summary:
Opens the <video grabber> window.

Associations: video library

Introduced: 2.0

OS: windows

Platforms: desktop

Security: disk, privacy

Example:
revInitializeVideoGrabber the short name of this stack, "VFW",the rect of this stack

Parameters:
parentStack:
The short name of the stack that the video-grabber should attach itself
to. 

videoMethod:
Must be "VFW".

grabberRect:
The rectangle of the video grabber window, and consists of four integers
separated by commas: the left, top, right, and bottom edges of the video
grabber, in absolute (screen) coordinates.

Description:
Use the <revInitializeVideoGrabber> <command> to start up 
<video capture> capability.

You must use the <revInitializeVideoGrabber> <command> before using any
of the other <command|commands> and <function|functions> in the 
<Video library>. The <command> does two things:

* Loads the code necessary for video capture into memory.
* Opens the video grabber window.


>*Note:* The <video grabber> is not a <stack window>, so you can't set
> its <properties>. To change the size and location of the 
> <video grabber>, use the <revSetVideoGrabberRect> <command>.

Once the video grabber is open, you can use the revVideoGrabDialog
<command> to specify where the video camera (or other video source) is
connected. Use the <revRecordVideo> <command> to record video from the
camera to a <file>, or use the <revPreviewVideo> command to display
video without saving it.

To use <VFW|Video for Windows> (on <Windows|Windows systems>), specify
"VFW".

To close the window and unload the video capture code, you should use
the <revCloseVideoGrabber> <command> when you're done with <video
capture>. 

>*Important:*  The <revInitializeVideoGrabber> <command> is part of the 
> <Video library>. To ensure that the <command> works in a 
> <standalone application>, you must include this 
> <LiveCode custom library|custom library> when you create your 
> <standalone application|standalone>. In the Inclusions pane of the 
> <Standalone Application Settings> window, make sure the
> "Video Grabber" library checkbox is checked.

Changes:
The use of <QuickTime> was deprecated in version 8.1 of LiveCode with
new defaults for <dontUseQT> and <dontUseQTEffects> as true on all
systems apart from pre OS X 10.8. The Windows build of LiveCode no
longer supports any <QuickTime> features and setting the <dontUseQT> and
<dontUseQTEffects> will have no effect.

Support for the "Video Grabber" library on Mac OS X ended in LiveCode
9.0.

References: revCloseVideoGrabber (command),
revSetVideoGrabberRect (command), revRecordVideo (command),
revPreviewVideo (command), revVideoGrabIdle (command),
revStopPreviewingVideo (command), stack window (glossary),
video capture (glossary), Windows (glossary), VFW (glossary),
Standalone Application Settings (glossary), video grabber (glossary),
standalone application (glossary), function (glossary),
command (glossary), LiveCode custom library (glossary), file (keyword),
Video library (library), properties (property), dontUseQT (property),
dontUseQTEffects (property)

Tags: multimedia

