Autodesk 64006-051108-9001 User Guide - Page 255

Glossary Glossary 2.21:1 Aspect Ratio - see Cinemascope. 3:2 Pulldown - a conversion of film frame rate material (24 fps) to NTSC video (29.97 fps), that results in the addition of approximately 6 frames per second. Pulldown frames are created by blending frames from the original source in a specific pattern and are very undesirable in compressed movies. Pulldown is introduced with a system called Telecine and can be removed with Cleaner Intelecine feature. 4:1:1 Color - uses chroma blocks 4 wide x 1 tall. Moderately compressed video color subsampling in which the luminance channel is not subsampled, but the chrominance channel has 1/4 the resolution. Most of the DV formats use 4:1:1 color. 4:2:0 Color - uses chroma blocks 2 wide x 2 tall. Moderately compressed video color subsampling that is very similar to 4:1:1. Standard color for MPEG. 4:2:2 Color - uses chroma blocks 2 wide x 1 tall. Mildly compressed video color subsampling in which the luminance channel is not subsampled, but the chrominance channel has half the resolution. Commonly used in professional digital video formats, such as Digital Betacam, D1, D5, D9, DVCPro-50 and Motion JPEG. While Betacam SP is often described as being 4:2:2, it is an analog format, and doesn't have a digital colorspace. 4:3 Aspect Ratio - common width-to-height display aspect ratio. 640x480 and 320x240 are examples of 4:3 aspect frame size.