TIFF 6.0 Specification
Final—June 3, 1992
PlanarConfiguration
How the components of each pixel are stored.
Tag
= 284 (11C.H)
Type = SHORT
N
1=
=1
Chunky
format. The component values for each pixel are stored contiguously.
The order of the components within the pixel is specified by
PhotometricInterpretation. For example, for RGB data, the data is stored as
RGBRGBRGB…
Planar
format. The components are stored in separate “component planes.” The
values in StripOffsets and StripByteCounts are then arranged as a 2-dimensional
array, with SamplesPerPixel rows and StripsPerImage columns. (All of the col-
umns for row 0 are stored first, followed by the columns of row 1, and so on.)
PhotometricInterpretation describes the type of data stored in each component
plane. For example, RGB data is stored with the Red components in one compo-
nent plane, the Green in another, and the Blue in another.
PlanarConfiguration=2 is not currently in widespread use and it is not recom-
mended for general interchange. It is used as an extension and Baseline TIFF
readers are not required to support it.
If SamplesPerPixel is 1, PlanarConfiguration is irrelevant, and need not be in-
cluded.
If a row interleave effect is desired, a writer might write out the data as
PlanarConfiguration=2—separate sample planes—but break up the planes into
multiple strips (one row per strip, perhaps) and interleave the strips.
2=
Default is 1. See also BitsPerSample, SamplesPerPixel.
ResolutionUnit
The unit of measurement for XResolution and YResolution.
Tag
= 296 (128.H)
Type = SHORT
N
=1
To be used with XResolution and YResolution.
1 = No absolute unit of measurement. Used for images that may have a non-square
aspect ratio, but no meaningful absolute dimensions.
The drawback of ResolutionUnit=1 is that different applications will import the image
at different sizes. Even if the decision is arbitrary, it might be better to use dots per
inch or dots per centimeter, and to pick XResolution and YResolution so that the
aspect ratio is correct and the maximum dimension of the image is about four inches
(the “four” is arbitrary.)
2=
3=
Inch.
Centimeter.
Default is 2.
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