JEITA CP-3451
- 19 -
JPEG compressed data or uncompressed YCbCr data. The TIFF default is 1 (centered); but when Y:Cb:Cr = 4:2:2
it is recommended in this standard that 2 (co-sited) be used to record data, in order to improve the image quality
when viewed on TV systems. When this field does not exist, the reader shall assume the TIFF default. In the case
of Y:Cb:Cr = 4:2:0, the TIFF default (centered) is recommended. If the reader does not have the capability of
supporting both kinds of YCbCrPositioning, it shall follow the TIFF default regardless of the value in this field. It is
preferable that readers be able to support both centered and co-sited positioning.
Tag
=
531 (213.H)
Type
=
SHORT
Count
=
1
Default
=
1
1
=
centered
2
=
co-sited
Other
=
reserved
Figure 8 YCbCrPositioning
XResolution
The number of pixels per ResolutionUnit in the ImageWidth direction. When the image resolution is unknown, 72
[dpi] is designated.
Tag
=
282 (11A.H)
Type
=
RATIONAL
Count
=
1
Default
=
72
YResolution
The number of pixels per ResolutionUnit in the ImageLength direction. The same value as XResolution is
designated.
Tag
=
283 (11B.H)
Type
=
RATIONAL
Count
=
1
YCbCrPositioning = 1
(centered)
YCbCrPositioning = 2
(co-sited)
Luminance Sample
Chrominance Sample
a) Y:Cb:Cr = 4:2:2
b) Y:Cb:Cr = 4:2:0
YCbCrPositioning = 1
(centered)
YCbCrPositioning = 2
(co-sited)