Apple Final Cut Pro 7 - Manual (Page 1899)

Anamorphic
Anamorphic techniques use special lenses or electronics to squeeze a widescreen image
to fit in a narrower aspect ratio. During projection or playback, the squeezed image is
stretched back to its original widescreen aspect ratio.
1.78 anamorphic 2.40 anamorphic
2.40 letterbox in
1.78 anamorphic
1.33 frame 1.33 frame 1.33 frame
Anamorphic video can also be letterboxed. For example, 16:9 anamorphic DVDs may
contain letterboxed 2.40 aspect ratio footage.
Pillarboxing
Pillarboxing displays movies with a small aspect ratio on a wide screen. Black bars appear
on the left and right sides of the frame.
1.33 pillarbox
1.78 frame
Frame Dimensions, Number of Lines, and Resolution
A video frame is composed of lines. In digital video, each line is sampled to create a
number of pixels (samples) per line. The more lines per frame, the higher the image
resolution. The more pixels per line, the higher the resolution of each line.
Number of Lines
NTSC uses 525 lines, whereas PAL uses 625. In analog video, many lines are not actually
used for picture information, so the total numbers relevant for the picture are somewhat
smaller: 486 lines for NTSC and 576 lines for PAL. HD formats defined by the ATSC have
either 1080 or 720 active picture lines per frame.
1899 Appendix B Video Formats