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4Introduction to the TIFF Documentation
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11Introduction to the TIFF Documentation
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16The following definitions are used throughout this documentation.
17They are consistent with the terminology used in the TIFF 6.0 specification.
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20<DT><I>Sample</I>
21<DD>The unit of information stored in an image; often called a
22  channel elsewhere.  Sample values are numbers, usually unsigned
23  integers, but possibly in some other format if the SampleFormat
24  tag is specified in a TIFF
25<DT><I>Pixel</I>
26<DD>A collection of one or more samples that go together.
27<DT><I>Row</I>
28<DD>An Nx1 rectangular collection of pixels.
29<DT><I>Tile</I>
30<DD>An NxM rectangular organization of data (or pixels).
31<DT><I>Strip</I>
32<DD>A tile whose width is the full image width.
33<DT><I>Compression</I>
34<DD>A scheme by which pixel or sample data are stored in
35  an encoded form, specifically with the intent of reducing the
36  storage cost.
37<DT><I>Codec</I>
38<DD>Software that implements the decoding and encoding algorithms
39  of a compression scheme.
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43In order to better understand how TIFF works (and consequently this
44software) it is important to recognize the distinction between the
45physical organization of image data as it is stored in a TIFF and how
46the data is interpreted and manipulated as pixels in an image.  TIFF
47supports a wide variety of storage and data compression schemes that
48can be used to optimize retrieval time and/or minimize storage space.
49These on-disk formats are independent of the image characteristics; it
50is the responsibility of the TIFF reader to process the on-disk storage
51into an in-memory format suitable for an application.  Furthermore, it
52is the responsibility of the application to properly interpret the
53visual characteristics of the image data.  TIFF defines a framework for
54specifying the on-disk storage format and image characteristics with
55few restrictions.  This permits significant complexity that can be
56daunting.  Good applications that handle TIFF work by handling as wide
57a range of storage formats as possible, while constraining the
58acceptable image characteristics to those that make sense for the
59application.
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65Last updated: $Date: 2016-09-25 20:05:44 $
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