1. In a digital video system, a sampling structure where the luminance and color-difference samples are generated from pixels arranged on one of two congruent rectilinear grids. Note: One grid is displaced horizontally from the other by half the horizontal pixel spacing. The alternate grid is usually chosen for alternate lines, but may also be chosen for alternate field/frames. 2. In a digital video system, a sampling structure with an array of samples where alternate rows of pixel samples are displaced horizontally in the grid by half of the pitch of the pixel samples along the remaining rows. Note: The name of this sampling was chosen directly from the classical Latin, quincunx, for the symbolic resemblance to the figure "5" (as seen in the "X" arrangement of pips on dice or playing cards. )