Y'CbCr The color space in which many digital video formats store data. Three components are stored for each pixel—one for luma (Y) and two for color information (Cb for the blue difference signal and Cr for the red difference signal). Also referred to as YUV. See also pixel. Zoom tool The editing tool that allows you to zoom in to or out of the Timeline. You can select the Zoom tool by pressing the Z key.