The area of a TV frame that carries picture information. Outside the active area there are line and field blanking which roughly, but not exactly, correspond to the areas defined for the original 525-and 625-line analogue systems. In digital versions of these, the blanked/active areas are defined by ITU-R BT.601, SMPTE RP125 and EBU-E.

For 1125-line HDTV (1080 active lines), which may have 60, 30, 25 or 24 Hz frame rates (and more), the active lines are always the same length – 1920 pixel samples at 74.25 MHz – a time of 25.86 microseconds – defined in SMPTE 274M and ITU-R.BT 709-4. Only their line blanking differs so the active portion may be mapped pixel-for-pixel between these formats. DTV standards tend to be quoted by their active picture content, e.g. 1920 x 1080, 1280 x 720, 720 x 576.

For both 625 and 525 line formats active line length is 720 luminance samples at 13.5 MHz = 53.3 microseconds. In digital video there are no half lines as there are in analogue. The table below shows blanking for SD and some popular HD standards.