1*0ef31e1fSMike Welles<HTML> 2*0ef31e1fSMike Welles<HEAD> 3*0ef31e1fSMike Welles<TITLE> 4*0ef31e1fSMike WellesIntroduction to the TIFF Documentation 5*0ef31e1fSMike Welles</TITLE> 6*0ef31e1fSMike Welles</HEAD> 7*0ef31e1fSMike Welles 8*0ef31e1fSMike Welles<H1> 9*0ef31e1fSMike Welles<IMG SRC=images/strike.gif WIDTH=128 HEIGHT=100 ALIGN=left HSPACE=6> 10*0ef31e1fSMike WellesIntroduction to the TIFF Documentation 11*0ef31e1fSMike Welles</H1> 12*0ef31e1fSMike Welles 13*0ef31e1fSMike Welles 14*0ef31e1fSMike Welles<H5> 15*0ef31e1fSMike WellesThis documentation is best viewed using a graphical browser that supports 16*0ef31e1fSMike Wellesthe latest HTML directives for formatting documents. In particular, 17*0ef31e1fSMike Wellesthis document was authored 18*0ef31e1fSMike Wellesfor viewing with version 1.1 or newer of the 19*0ef31e1fSMike Welles<A HREF="http://home.mcom.com/comprod/products/navigator/index.html">Netscape Navigator</A>. 20*0ef31e1fSMike Welles</H5> 21*0ef31e1fSMike Welles 22*0ef31e1fSMike Welles<BR CLEAR=left> 23*0ef31e1fSMike Welles 24*0ef31e1fSMike Welles<P> 25*0ef31e1fSMike WellesThe following definitions are used throughout this documentation. 26*0ef31e1fSMike WellesThey are consistent with the terminology used in the TIFF 6.0 specification. 27*0ef31e1fSMike Welles 28*0ef31e1fSMike Welles<DL> 29*0ef31e1fSMike Welles<DT><I>Sample</I> 30*0ef31e1fSMike Welles<DD>The unit of information stored in an image; often called a 31*0ef31e1fSMike Welles channel elsewhere. Sample values are numbers, usually unsigned 32*0ef31e1fSMike Welles integers, but possibly in some other format if the SampleFormat 33*0ef31e1fSMike Welles tag is specified in a TIFF 34*0ef31e1fSMike Welles<DT><I>Pixel</I> 35*0ef31e1fSMike Welles<DD>A collection of one or more samples that go together. 36*0ef31e1fSMike Welles<DT><I>Row</I> 37*0ef31e1fSMike Welles<DD>An Nx1 rectangular collection of pixels. 38*0ef31e1fSMike Welles<DT><I>Tile</I> 39*0ef31e1fSMike Welles<DD>An NxM rectangular organization of data (or pixels). 40*0ef31e1fSMike Welles<DT><I>Strip</I> 41*0ef31e1fSMike Welles<DD>A tile whose width is the full image width. 42*0ef31e1fSMike Welles<DT><I>Compression</I> 43*0ef31e1fSMike Welles<DD>A scheme by which pixel or sample data are stored in 44*0ef31e1fSMike Welles an encoded form, specifically with the intent of reducing the 45*0ef31e1fSMike Welles storage cost. 46*0ef31e1fSMike Welles<DT><I>Codec</I> 47*0ef31e1fSMike Welles<DD>Software that implements the decoding and encoding algorithms 48*0ef31e1fSMike Welles of a compression scheme. 49*0ef31e1fSMike Welles</UL> 50*0ef31e1fSMike Welles 51*0ef31e1fSMike Welles<P> 52*0ef31e1fSMike WellesIn order to better understand how TIFF works (and consequently this 53*0ef31e1fSMike Wellessoftware) it is important to recognize the distinction between the 54*0ef31e1fSMike Wellesphysical organization of image data as it is stored in a TIFF and how 55*0ef31e1fSMike Wellesthe data is interpreted and manipulated as pixels in an image. TIFF 56*0ef31e1fSMike Wellessupports a wide variety of storage and data compression schemes that 57*0ef31e1fSMike Wellescan be used to optimize retrieval time and/or minimize storage space. 58*0ef31e1fSMike WellesThese on-disk formats are independent of the image characteristics; it 59*0ef31e1fSMike Wellesis the responsibility of the TIFF reader to process the on-disk storage 60*0ef31e1fSMike Wellesinto an in-memory format suitable for an application. Furthermore, it 61*0ef31e1fSMike Wellesis the responsibility of the application to properly interpret the 62*0ef31e1fSMike Wellesvisual characteristics of the image data. TIFF defines a framework for 63*0ef31e1fSMike Wellesspecifying the on-disk storage format and image characteristics with 64*0ef31e1fSMike Wellesfew restrictions. This permits significant complexity that can be 65*0ef31e1fSMike Wellesdaunting. Good applications that handle TIFF work by handling as wide 66*0ef31e1fSMike Wellesa range of storage formats as possible, while constraining the 67*0ef31e1fSMike Wellesacceptable image characteristics to those that make sense for the 68*0ef31e1fSMike Wellesapplication. 69*0ef31e1fSMike Welles 70*0ef31e1fSMike Welles 71*0ef31e1fSMike Welles<P> 72*0ef31e1fSMike Welles<HR> 73*0ef31e1fSMike Welles 74*0ef31e1fSMike Welles<ADDRESS> 75*0ef31e1fSMike Welles<A HREF="sam.html">Sam Leffler</A> / <A HREF="mailto:[email protected]">[email protected]</A>. 76*0ef31e1fSMike WellesLast updated: $Date: 1999-07-27 21:50:27 $ 77*0ef31e1fSMike Welles</ADDRESS> 78*0ef31e1fSMike Welles 79*0ef31e1fSMike Welles</BODY> 80*0ef31e1fSMike Welles</HTML> 81
