DigitalVideoAndHDTVAlgorithmsAndInterfaces.pdf

M-JPEG A technique or file format using JPEG (2), or a JPEG-like algorithm,
to individually compress each field or frame in a motion
image sequence, without exploiting interfield or interframe coherence.
M-JPEG is not standardized.
M/NTSC See NTSC (3), on page 639.
M/PAL See PAL-M, PAL-525, on page 640.
MAC 1. Multiplexed analog component: An obsolete component video
encoding standard, used mainly with 576i scanning, encoding
Y’P B P R color components in time-compressed serial analog form.
P B and P R are compressed by a factor of two with respect to Y’.
2. Multiplier-accumulator. An arithmetic device comprising
a multiplier followed by an accumulator that is arranged to sum
consecutive products.
Macroblock 1. In MPEG, image data comprising, or coded picture information
representing, one of the 16×16 arrays of luma samples that tile
the image, accompanied by the requisite number and arrangement
of associated blocks of C B and C R . In the common MPEG-2
case of 4:2:0 chroma subsampling, four 8×8 luma blocks are
accompanied by an 8×8 block of C B and 8×8 block of C R ; in this
case, a macroblock comprises six blocks.
2. In DV, image data comprising – or coded picture information
representing – an 8×8 block of C B , an 8×8 block of C R , and the
associated two (4:2:2), three (3:1:1), four (4:1:1 or 4:2:0), or six
(3:1:0) 8×8 blocks of luma.
3. In JPEG, an MCU (minimum coded unit; see page 637).
Mathematical PAL See PAL, mathematical, on page 640.
MB Megabyte: 2 20 (or 1048576) bytes, or in disk storage, 2 10 ·10 3 (or
1024000) bytes.
MB See Macroblock, above.
MCU, minimum coded unit In JPEG without subsampling, image data comprising, or coded
picture information representing, a set of 8×8 blocks of image
data, one per component. In Y’C B C R JPEG, with 4:2:0 subsampling,
image data comprising, or coded picture information representing,
an 8×8 block of C B , the corresponding 8×8 block of C R ,
and the four associated 8×8 luma blocks.
Meander, burst See Burst meander, on page 616.
Metamerism 1. In color science, the condition that two different spectral power
distributions, when weighted according to the three spectral
response curves of the CIE Standard Observer, produce identical
tristimulus values – that is, appear to be the same color to a colornormal
observer. Metamerism frequently holds for spectra that are
markedly different.
GLOSSARY OF VIDEO SIGNAL TERMS 637