Words and pictures Barry Beckham/David Rowley
The stroke cammand applies pixels to any of the selection tools. It's found in the edit menu and will be greyed out until you make a selection. We have created a black oblong and made an oval selection as shown.
1 When you call up the stroke command the palette below appears.
2 You can choose the width of the line in pixels, the colour of those pixels and decide if you want the line inside the selection, outside or in the centre. Applying the settings shown above will give you the result below. The colour that appears in the colour box will default to your chosen foreground colour in your colour stroke.
3 The stroke command is most often used to add a thin line to the outer edge of an image. To select the outer edge of any image hit the shortcut keys Ctrl A.
A thin line around the edge of a light image like this just provides that extra something to hold it all together.
The same is true in reverse where a white line can make all the difference to a dark image on a dark background, but any colour can be used not just black or white.