TIFF 6.0 Specification
Final—June 3, 1992
8 = The 0th row represents the visual left-hand side of the image, and the 0th column
represents the visual bottom.
Default is 1.
Support for orientations other than 1 is not a Baseline TIFF requirement.
PhotometricInterpretation
The color space of the image data.
Tag
= 262 (106.H)
Type = SHORT
N
0=
=1
WhiteIsZero. For bilevel and grayscale images: 0 is imaged as white.
2**BitsPerSample-1 is imaged as black. This is the normal value for Compres-
sion=2.
BlackIsZero. For bilevel and grayscale images: 0 is imaged as black.
2**BitsPerSample-1 is imaged as white. If this value is specified for Compres-
sion=2, the image should display and print reversed.
RGB. In the RGB model, a color is described as a combination of the three pri-
mary colors of light (red, green, and blue) in particular concentrations. For each of
the three components, 0 represents minimum intensity, and 2**BitsPerSample - 1
represents maximum intensity. Thus an RGB value of (0,0,0) represents black,
and (255,255,255) represents white, assuming 8-bit components. For
PlanarConfiguration = 1, the components are stored in the indicated order: first
Red, then Green, then Blue. For PlanarConfiguration = 2, the StripOffsets for the
component planes are stored in the indicated order: first the Red component plane
StripOffsets, then the Green plane StripOffsets, then the Blue plane StripOffsets.
1=
2=
3= Palette color. In this model, a color is described with a single component. The
value of the component is used as an index into the red, green and blue curves in
the ColorMap field to retrieve an RGB triplet that defines the color. When
PhotometricInterpretation=3 is used, ColorMap must be present and
SamplesPerPixel must be 1.
4=
Transparency Mask.
This means that the image is used to define an irregularly shaped region of another
image in the same TIFF file. SamplesPerPixel and BitsPerSample must be 1.
PackBits compression is recommended. The 1-bits define the interior of the re-
gion; the 0-bits define the exterior of the region.
A reader application can use the mask to determine which parts of the image to
display. Main image pixels that correspond to 1-bits in the transparency mask are
imaged to the screen or printer, but main image pixels that correspond to 0-bits in
the mask are not displayed or printed.
The image mask is typically at a higher resolution than the main image, if the
main image is grayscale or color so that the edges
can be sharp.
There is no default for PhotometricInterpretation,
and it is required.
Do not rely
on applications defaulting to what you want.
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