ANY-maze Help > The ANY-maze reference > The Protocol page > The elements of a protocol > Apparatus > Video sources > Setting up a Video Source > The Camera/Digitizer properties window > Image control page

Image control page

In brief

This page of the Camera/Digitizer properties window allows you to change the appearance of the video image provided by your camera or digitizer.

Details

Changing the appearance of a video image can be critical in ANY-maze, as it will be hard for the system to track in a very dark image or one with very low contrast. When using the controls on this page, you should try to create an image which is pleasing to you - in other words, not too bright, not too dark, nice realistic contrast, etc. In general, an image which looks good to you will also look good to the software.

However, there are two situations when you may need to use these settings to create a less natural image: when there's low contrast between the animal and the apparatus background, and/or when you're tracking in low light. For full details on the considerations in these situations, refer to: Tracking with low contrast between the animal and apparatus background and Working in low light or darkness.

The actual settings available are:

Brightness

This is self-explanatory.

Contrast

This is self-explanatory, but be aware that some devices can report that they support changes to contrast but then don't actually alter it.

White level

Setting the white level is supported by some digitizers and can be very useful in low light. Essentially, the white level is the level of the video signal above which the digitizer considers everything to be fully white. If an image has low light then it will, naturally, be rather dark and won't have any area which is 'fully white'. By reducing the white level, you can alter this so that whatever the brightest thing in the image is (even if it's actually quite dark) is considered to be fully white and everything darker is considered to be progressively darker shades of grey.

Black level

Setting the black level, which is supported by some digitizers, is much like setting the white level only this time you're setting the level of the video signal below which the digitizer will consider everything to be fully black. This is less useful than setting the white level, but can still be beneficial in low light as by increasing the black level you can concentrate the digitizer's resolution on a narrower band of the video signal, thus improving the image.

Gain	Altering the image gain effectively amplifies the video signal. Again, in low light this can be useful, although as it also amplifies noise, the image will become noisier - fortunately, ANY-maze is fairly immune to image noise so this shouldn't be a problem.

ANY-maze help topic T0106