Video Capture Service

This is a stub document.

Available grabber drivers

Quicktime Driver

Availability: MacOS X Not Linux Not Windows

This driver allows GML to capture from any camera recognized by Quicktime.

In particular, almost all Firewire cameras are supported (e.g. Unibrain or Marlin), as well as many USB webcams (e.g. the ToUcam) if you have a third-party driver installed

Active Silicon LFG Driver

Availability: MacOS X Not Linux Not Windows

This driver interfaces with the AS-LFG SDK provided with the capture boards manufactured by Active Silicon ltd.

Linux IEEE1394 Driver

Availability: Not MacOS X Linux Not Windows

This driver, based on the standard ieee1394 SDKs available since Linux 2.6 (libraw1394 and libdc1394), allows to interface with most Firewire video cameras, like the Quicktime driver.

Video For Linux 2 Driver

Availability: Not MacOS X Linux Not Windows

This driver abstracts the v4l2 API. It allows to capture from commodity digitizer boards, e.g. all the boards based on the bt848, bt878 or saa7130/34 chips.

Shared Memory Driver

Availability: MacOS X Linux Windows

This driver acts as a proxy for the instances of other drivers. It allows multiple clients to access the same video stream.

Video capture in GML

programmer interface

% set l [gmlGrabber --list]
{QuickTime (IIDC FireWire Video, unibrain Fire-i)}
{QuickTime (IIDC FireWire Video, Camera)} {QuickTime (ToUcam, ToUcam)}
% gmlGrabber g1 -reduce 2 -name [lindex $l 0]
g1
% gmlGrabber g2 -reduce 2 -name [lindex $l 1]
g2
% gmlGrabber g3 -reduce 2 -name [lindex $l 2]
g3
% gmlGrabberMonitor .g1 g1
.g1
% gmlGrabberMonitor .g2 g2
.g2
% gmlGrabberMonitor .g3 g3
.g3

Photo taken while capturing and displaying three video streams (320x240 @30Hz) from three video cameras: a Philips ToUCam (USB), a Cool-Stream iSweet (Firewire), and a Unibrain Fire-i (Firewire).

Screenshot corresponding to the above photo.