Creating pixel selections

A pixel selection is simply a drawn area on your image (bounded by a flashing dashed line, often called 'marching ants'). A selection is created for various reasons:

• To limit editing (e.g., painting, applying fills, etc.) to within that selection area only.
• To selectively copy pixels.
• As a precursor to creating a mask layer.
• To draw areas for removal (cutout).

Selection boundaries are defined depending on whether individual pixels are included or excluded.

Once your selection has been created, you can invert it so all included pixels are excluded and vice versa.

Selection tools

There are several tools you can use to create pixel selections:

• Selection Brush Tool (see Painting pixel selections)
• Flood Select Tool (see Flooding pixel selections)
• Rectangular Marquee Tool (see Marquee pixel selections)
• Elliptical Marquee Tool
• Column Marquee Tool
• Row Marquee Tool
• Freehand Selection (see Drawing pixel selections)

Selection procedures

Alongside the many selection tools available, there are also a variety of procedures you can follow to create a pixel selection from:

• The contents of a layer (see Pixel selections from layers)
• The luminance of a layer (see Pixel selections from layers)
• Layer and composite channels (see Pixel selections from channels)
• Curves and shapes (see Pixel selections from shapes)
• Tonal or colour ranges (see Range pixel selections)
• Sampled colours (see Sampled colour pixel selections)
• Quick Masks (see Edit selection as layer using Quick Mask)
• Previously created selections (see Creating outline selections)

Selection modes

When working with, and creating, selections, you may have access to the following Modes which affect how your selection develops:

• New—cancels all current selections and creates a new selection.
• Add—adds areas to the current selection. If there is no selection in place, a new selection will be created.
• Subtract—removes areas from the current selection.
• Intersect—a new selection area is created from the overlap between the newly added selection area and the current selection.