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Introduction to the TIFF Documentation
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Introduction to the TIFF Documentation
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<P>
The following definitions are used throughout this documentation.
They are consistent with the terminology used in the TIFF 6.0 specification.

<DL>
<DT><I>Sample</I>
<DD>The unit of information stored in an image; often called a
  channel elsewhere.  Sample values are numbers, usually unsigned
  integers, but possibly in some other format if the SampleFormat
  tag is specified in a TIFF
<DT><I>Pixel</I>
<DD>A collection of one or more samples that go together.
<DT><I>Row</I>
<DD>An Nx1 rectangular collection of pixels.
<DT><I>Tile</I>
<DD>An NxM rectangular organization of data (or pixels).
<DT><I>Strip</I>
<DD>A tile whose width is the full image width.
<DT><I>Compression</I>
<DD>A scheme by which pixel or sample data are stored in
  an encoded form, specifically with the intent of reducing the
  storage cost.
<DT><I>Codec</I>
<DD>Software that implements the decoding and encoding algorithms
  of a compression scheme.
</UL>

<P>
In order to better understand how TIFF works (and consequently this
software) it is important to recognize the distinction between the
physical organization of image data as it is stored in a TIFF and how
the data is interpreted and manipulated as pixels in an image.  TIFF
supports a wide variety of storage and data compression schemes that
can be used to optimize retrieval time and/or minimize storage space.
These on-disk formats are independent of the image characteristics; it
is the responsibility of the TIFF reader to process the on-disk storage
into an in-memory format suitable for an application.  Furthermore, it
is the responsibility of the application to properly interpret the
visual characteristics of the image data.  TIFF defines a framework for
specifying the on-disk storage format and image characteristics with
few restrictions.  This permits significant complexity that can be
daunting.  Good applications that handle TIFF work by handling as wide
a range of storage formats as possible, while constraining the
acceptable image characteristics to those that make sense for the
application.


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Last updated: $Date: 1999/08/09 20:21:21 $

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Commit	Line	Data
8414a40c VZ	1	<HTML>
	2	<HEAD>
	3	<TITLE>
	4	Introduction to the TIFF Documentation
	5	</TITLE>
	6	</HEAD>
	7	<BODY BGCOLOR=white>
	8	<FONT FACE="Arial, Helvetica, Sans">
	9	<H1>
	10	<IMG SRC=images/strike.gif WIDTH=128 HEIGHT=100 ALIGN=left HSPACE=6>
	11	Introduction to the TIFF Documentation
	12	</H1>
	13
	14
	15	<P>
	16	The following definitions are used throughout this documentation.
	17	They are consistent with the terminology used in the TIFF 6.0 specification.
	18
	19	<DL>
	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.
	40	</UL>
	41
	42	<P>
	43	In order to better understand how TIFF works (and consequently this
	44	software) it is important to recognize the distinction between the
	45	physical organization of image data as it is stored in a TIFF and how
	46	the data is interpreted and manipulated as pixels in an image. TIFF
	47	supports a wide variety of storage and data compression schemes that
	48	can be used to optimize retrieval time and/or minimize storage space.
	49	These on-disk formats are independent of the image characteristics; it
	50	is the responsibility of the TIFF reader to process the on-disk storage
	51	into an in-memory format suitable for an application. Furthermore, it
	52	is the responsibility of the application to properly interpret the
	53	visual characteristics of the image data. TIFF defines a framework for
	54	specifying the on-disk storage format and image characteristics with
	55	few restrictions. This permits significant complexity that can be
	56	daunting. Good applications that handle TIFF work by handling as wide
	57	a range of storage formats as possible, while constraining the
	58	acceptable image characteristics to those that make sense for the
	59	application.
	60
	61
	62	<P>
	63	<HR>
	64
65	Last updated: $Date: 1999/08/09 20:21:21 $
66
67	</BODY>
68	</HTML>