Single frame grab from webcam

Single frame grab from webcam

inversemedia's picture

Thanks all in advance, helping my son with a QC science fair project and we're newbies so appreciate any guidance...

We've built a rig to photograph peoples irises using a USB webcam, able to select it (video input patch) and getting a realtime stream to the billboard.

**Any hints at how to trigger (via spacebar) a single frame grab of that stream? **

Looking to grab a single frame (and then if it was a bad image or if they blinked,toggle the spacebar to get another single frame grab) and then use that as the basis for selecting a region of interest (the iris) and then doing some pixel by pixel analysis for color content.

BTW I found that the Logitech c920 webcam is HD res, and using Webcam settings app By Mactaris, lets you override the autofocus, control gain and many other settings. http://mactaris.blogspot.com/p/webcam-settings.html