gqcam is a webcam application that assists in taking snapshots or automatic picture series with webcams. To use gqcam, your webcam must be supported by Video4Linux. Many USB webcams, like the Logitech Quickcam Express, are automatically recognized. Grayscale and color cameras can be used. TV cards that support Video4Linux can also be used as an image source. An overview of the supported USB devices is maintained at http://www.linux-usb.org. A graphical user interface is not compulsory because gqcam can also run from the command line.
Connect your camera to the USB port of your computer before starting gqcam. Then run gqcam. The current picture of your webcam is automatically shown in the upper part of the application window. The lower part has sliders for adjusting the brightness, white balance, contrast, tint, and color saturation as needed. The brightness is automatically preset. This feature can be set in
in + . features false color correction switches because some cameras swap the red and blue channels in transmission.
If you operate more than one webcam, use
/dev/video0
, the second
is attached to /dev/video1
, and
so on.
To take a snapshot with a camera, click
. Select a filename and picture format in the dialog that opens. Create a picture series with + . Set the capturing frequency in seconds or minutes along with the properties of the images in . An optional script to run after every capture event can be chosen with . This could, for example, be used to upload the captured image onto an FTP server.
gqcam can also be run without its graphical user interface. This may be
interesting, for instance, for automatic surveillance controlled by a cron
job. This requires that all the necessary settings be passed to the
application as parameters. Running gqcam -t
JPEG
-s
-d webcam.jpg
saves the
current image captured by the camera with the filename
webcam.jpg
. The option -t
defines the
file format. Possible values are JPEG, PNG, and PPM. The command line switch
-s
activates the color correction. The filename for saving
is passed with the option -d
. If more than one webcam is
operated, the name of the device must be passed. If no device is given, the
default device /dev/video0
is used. To capture an image
from the second camera, the option -v /dev/video1
must be
added. List all options with gqcam
--help
.