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4TIFF 6.0 Specification Coverage
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10<IMG SRC=images/strike.gif WIDTH=128 HEIGHT=100 ALIGN=left HSPACE=6>
11TIFF 6.0 Specification Coverage
12</H1>
13
14
15<P>
16The library is capable of dealing with images that are written to
17follow the 5.0 or 6.0 TIFF spec.  There is also considerable support
18for some of the more esoteric portions of the 6.0 TIFF spec.
19
20<P>
21<TABLE BORDER CELLPADDING=3>
22
23<TR>
24<TD VALIGN=top>
25<I>Core requirements</I>
26</TD>
27<TD>
28Both <TT>"MM"</TT> and <TT>"II"</TT> byte orders are handled.
29Both packed and separated planar configuration of samples.
30Any number of samples per pixel (memory permitting).
31Any image width and height (memory permitting).
32Multiple subfiles can be read and written.
33Editing is <B>not</B> supported in that related subfiles (e.g.
34a reduced resolution version of an image) are not automatically
35updated.
36<P>
37Tags handled:
38<TT>ExtraSamples</TT>,
39<TT>ImageWidth</TT>,
40<TT>ImageLength</TT>,
41<TT>NewSubfileType</TT>,
42<TT>ResolutionUnit</TT>.
43<TT>Rowsperstrip</TT>,
44<TT>StripOffsets</TT>,
45<TT>StripByteCounts</TT>,
46<TT>XResolution</TT>,
47<TT>YResolution</TT>,
48</TD>
49</TR>
50
51<TR>
52<TD VALIGN=top><I>Tiled Images</I></TD>
53<TD><TT>TileWidth</TT>,
54    <TT>TileLength</TT>,
55    <TT>TileOffsets</TT>,
56    <TT>TileByteCounts</TT>
57</TD>
58</TR>
59
60<TD VALIGN=top><I>Image Colorimetry Information</I></TD>
61<TD><TT>WhitePoint</TT>,
62    <TT>PrimaryChromaticities</TT>,
63    <TT>TransferFunction</TT>,
64    <TT>ReferenceBlackWhite</TT>
65</TD>
66</TR>
67
68<TR>
69<TD VALIGN=top><I>Class B for bilevel images</I></TD>
70<TD><TT>SamplesPerPixel</TT> = 1<BR>
71    <TT>BitsPerSample</TT> = 1<BR>
72    <TT>Compression</TT> = 1 (none), 2 (CCITT 1D), or 32773 (PackBits)<BR>
73    <TT>PhotometricInterpretation</TT> = 0 (Min-is-White), 1 (Min-is-Black)<BR>
74</TD>
75</TR>
76
77<TR>
78<TD VALIGN=top><I>Class G for grayscale images</I></TD>
79<TD><TT>SamplesPerPixel</TT> = 1<BR>
80    <TT>BitsPerSample</TT> = 4, 8<BR>
81    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
82    <TT>PhotometricInterpretation</TT> = 0 (Min-is-White), 1 (Min-is-Black)<BR>
83</TD>
84
85</TR>
86<TR>
87<TD VALIGN=top><I>Class P for palette color images</I></TD>
88<TD><TT>SamplesPerPixel</TT> = 1<BR>
89    <TT>BitsPerSample</TT> = 1-8<BR>
90    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
91    <TT>PhotometricInterpretation</TT> = 3 (Palette RGB)<BR>
92    <TT>ColorMap</TT>
93</TD>
94</TR>
95
96<TR>
97<TD VALIGN=top><I>Class R for RGB full color images</I></TD>
98<TD><TT>SamplesPerPixel</TT> = 3<BR>
99    <TT>BitsPerSample</TT> = <8,8,8><BR>
100    <TT>PlanarConfiguration</TT> = 1, 2<BR>
101    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
102    <TT>PhotometricInterpretation</TT> = 2 (RGB)<BR>
103</TD>
104</TR>
105
106<TR>
107<TD VALIGN=top><I>Class F for facsimile</I></TD>
108<TD>(<I>Class B tags plus...</I>)<BR>
109    <TT>Compression</TT> = 3 (CCITT Group 3), 4 (CCITT Group 4)<BR>
110    <TT>FillOrder</TT> = 1 (MSB), 2 (LSB)<BR>
111    <TT>Group3Options</TT> = 1 (2d encoding), 4 (zero fill), 5 (2d+fill)<BR>
112    <TT>ImageWidth</TT> = 1728, 2048, 2482<BR>
113    <TT>NewSubFileType</TT> = 2<BR>
114    <TT>ResolutionUnit</TT> = 2 (Inch), 3 (Centimeter)<BR>
115    <TT>PageNumber</TT>,
116    <TT>XResolution</TT>,
117    <TT>YResolution</TT>,
118    <TT>Software</TT>,
119    <TT>BadFaxLines</TT>,
120    <TT>CleanFaxData</TT>,
121    <TT>ConsecutiveBadFaxLines</TT>,
122    <TT>DateTime</TT>,
123    <TT>DocumentName</TT>,
124    <TT>ImageDescription</TT>,
125    <TT>Orientation</TT>
126</TD>
127</TR>
128
129<TD VALIGN=top><I>Class S for separated images</I></TD>
130<TD><TT>SamplesPerPixel</TT> = 4<BR>
131    <TT>PlanarConfiguration</TT> = 1, 2<BR>
132    <TT>Compression</TT> = 1 (none), 5 (LZW)<BR>
133    <TT>PhotometricInterpretation</TT> = 5 (Separated)<BR>
134    <TT>InkSet</TT> = 1 (CMYK)<BR>
135    <TT>DotRange</TT>,
136    <TT>InkNames</TT>,
137    <TT>DotRange</TT>,
138    <TT>TargetPrinter</TT>
139</TD>
140</TR>
141
142<TD VALIGN=top><I>Class Y for YCbCr images</I></TD>
143<TD><TT>SamplesPerPixel</TT> = 3<BR>
144    <TT>BitsPerSample</TT> = <8,8,8><BR>
145    <TT>PlanarConfiguration</TT> = 1, 2<BR>
146    <TT>Compression</TT> = 1 (none),  5 (LZW), 7 (JPEG)<BR>
147    <TT>PhotometricInterpretation</TT> = 6 (YCbCr)<BR>
148    <TT>YCbCrCoefficients</TT>,
149    <TT>YCbCrSubsampling</TT>,
150    <TT>YCbCrPositioning</TT><BR>
151    (<I>colorimetry info from Appendix H; see above</I>)
152</TD>
153</TR>
154
155<TR>
156<TD VALIGN=top><I>Class "JPEG" for JPEG images (per TTN2)</I></TD>
157<TD><TT>PhotometricInterpretation</TT> = 1 (grayscale), 2 (RGB), 5 (CMYK), 6 (YCbCr)<BR>
158    (<I>Class Y tags if YCbCr</I>)<BR>
159    (<I>Class S tags if CMYK</I>)<BR>
160    <TT>Compression</TT> = 7 (JPEG)<BR>
161</TD>
162</TR>
163</TABLE>
164
165<P>
166In addition, the library supports some optional compression algorithms
167that are, in some cases, of dubious value.
168
169<PRE>
170    Compression = 32766	NeXT 2-bit encoding
171    Compression = 32809	ThunderScan 4-bit encoding
172    Compression = 32909	Pixar companded 11-bit ZIP encoding
173    Compression = 32946	PKZIP-style Deflate encoding (experimental)
174    Compression = 34676	SGI 32-bit Log Luminance encoding (experimental)
175    Compression = 34677	SGI 24-bit Log Luminance encoding (experimental)
176</PRE>
177
178Note that there is no support for the JPEG-related tags defined
179in the 6.0 specification; the JPEG support is based on the post-6.0
180proposal given in TIFF Technical Note #2.
181
182<P>
183<TABLE>
184<TR>
185<TD VALIGN=top><IMG SRC="images/info.gif"></TD>
186<TD>
187<EM>
188For more information on the experimental Log Luminance encoding
189consult the materials available at
190<A HREF=http://www.sgi.com/Technology/pixformat>http://www.sgi.com/Technology/pixformat</A>.
191</EM>
192</TD>
193</TR>
194</TABLE>
195
196<P>
197The following table shows the tags that are recognized
198and how they are used by the library.  If no use is indicated,
199then the library
200reads and writes the tag, but does not use it internally.
201
202<P>
203<TABLE BORDER WIDTH=100% CELLPADDING=2>
204<TR>
205<TH ALIGN=left>Tag Name</TH> <TH>Value</TH> <TH ALIGN=center>R/W</TH> <TH ALIGN=left>Library's Use (Comments)</TH>
206</TR>
207<TR>
208<TD><TT>NewSubFileType</TT></TD>
209<TD ALIGN=center>254</TD>
210<TD ALIGN=center>R/W</TD>
211<TD>none (called <TT>SubFileType</TT> in &lt;tiff.h&gt;)</TD>
212</TR>
213<TR>
214<TD><TT>SubFileType</TT></TD>
215<TD ALIGN=center>255</TD>
216<TD ALIGN=center>R/W</TD>
217<TD>none (called <TT>OSubFileType</TT> in &lt;tiff.h&gt;)</TD>
218</TR>
219<TR>
220<TD><TT>ImageWidth</TT></TD>
221<TD ALIGN=center>256</TD>
222<TD ALIGN=center>R/W</TD>
223<TD>lots</TD>
224</TR>
225<TR>
226<TD><TT>ImageLength</TT></TD>
227<TD ALIGN=center>257</TD>
228<TD ALIGN=center>R/W</TD>
229<TD>lots</TD>
230</TR>
231<TR>
232<TD><TT>BitsPerSample</TT></TD>
233<TD ALIGN=center>258</TD>
234<TD ALIGN=center>R/W</TD>
235<TD>lots</TD>
236</TR>
237<TR>
238<TD><TT>Compression</TT></TD>
239<TD ALIGN=center>259</TD>
240<TD ALIGN=center>R/W</TD>
241<TD>to select appropriate codec</TD>
242</TR>
243<TR>
244<TD><TT>PhotometricInterpretation</TT></TD>
245<TD ALIGN=center>262</TD>
246<TD ALIGN=center>R/W</TD>
247<TD>lots</TD>
248</TR>
249<TR>
250<TD><TT>Thresholding</TT></TD>
251<TD ALIGN=center>263</TD>
252<TD ALIGN=center>R/W</TD>
253<TD>&nbsp;</TD>
254</TR>
255<TR>
256<TD><TT>CellWidth</TT></TD>
257<TD ALIGN=center>264</TD>
258<TD>&nbsp;</TD>
259<TD>parsed but ignored</TD>
260</TR>
261<TR>
262<TD><TT>CellLength</TT></TD>
263<TD ALIGN=center>265</TD>
264<TD>&nbsp;</TD>
265<TD>parsed but ignored</TD>
266</TR>
267<TR>
268<TD><TT>FillOrder</TT></TD>
269<TD ALIGN=center>266</TD>
270<TD ALIGN=center>R/W</TD>
271<TD>control bit order</TD>
272</TR>
273<TR>
274<TD><TT>DocumentName</TT></TD>
275<TD ALIGN=center>269</TD>
276<TD ALIGN=center>R/W</TD>
277<TD>&nbsp;</TD>
278</TR>
279<TR>
280<TD><TT>ImageDescription</TT></TD>
281<TD ALIGN=center>270</TD>
282<TD ALIGN=center>R/W</TD>
283<TD>&nbsp;</TD>
284</TR>
285<TR>
286<TD><TT>Make</TT></TD>
287<TD ALIGN=center>271</TD>
288<TD ALIGN=center>R/W</TD>
289<TD>&nbsp;</TD>
290</TR>
291<TR>
292<TD><TT>Model</TT></TD>
293<TD ALIGN=center>272</TD>
294<TD ALIGN=center>R/W</TD>
295<TD>&nbsp;</TD>
296</TR>
297<TR>
298<TD><TT>StripOffsets</TT></TD>
299<TD ALIGN=center>273</TD>
300<TD ALIGN=center>R/W</TD>
301<TD>data i/o</TD>
302</TR>
303<TR>
304<TD><TT>Orientation</TT></TD>
305<TD ALIGN=center>274</TD>
306<TD ALIGN=center>R/W</TD>
307<TD>&nbsp;</TD>
308</TR>
309<TR>
310<TD><TT>SamplesPerPixel</TT></TD>
311<TD ALIGN=center>277</TD>
312<TD ALIGN=center>R/W</TD>
313<TD>lots</TD>
314</TR>
315<TR>
316<TD><TT>RowsPerStrip</TT></TD>
317<TD ALIGN=center>278</TD>
318<TD ALIGN=center>R/W</TD>
319<TD>data i/o</TD>
320</TR>
321<TR>
322<TD><TT>StripByteCounts</TT></TD>
323<TD ALIGN=center>279</TD>
324<TD ALIGN=center>R/W</TD>
325<TD>data i/o</TD>
326</TR>
327<TR>
328<TD><TT>MinSampleValue</TT></TD>
329<TD ALIGN=center>280</TD>
330<TD ALIGN=center>R/W</TD>
331<TD>&nbsp;</TD>
332</TR>
333<TR>
334<TD><TT>MaxSampleValue</TT></TD>
335<TD ALIGN=center>281</TD>
336<TD ALIGN=center>R/W</TD>
337<TD>&nbsp;</TD>
338</TR>
339<TR>
340<TD><TT>XResolution</TT></TD>
341<TD ALIGN=center>282</TD>
342<TD ALIGN=center>R/W</TD>
343<TD>&nbsp;</TD>
344</TR>
345<TR>
346<TD><TT>YResolution</TT></TD>
347<TD ALIGN=center>283</TD>
348<TD ALIGN=center>R/W</TD>
349<TD>used by Group 3 2d encoder</TD>
350</TR>
351<TR>
352<TD><TT>PlanarConfiguration</TT></TD>
353<TD ALIGN=center>284</TD>
354<TD ALIGN=center>R/W</TD>
355<TD>data i/o</TD>
356</TR>
357<TR>
358<TD><TT>PageName</TT></TD>
359<TD ALIGN=center>285</TD>
360<TD ALIGN=center>R/W</TD>
361<TD>&nbsp;</TD>
362</TR>
363<TR>
364<TD><TT>XPosition</TT></TD>
365<TD ALIGN=center>286</TD>
366<TD ALIGN=center>R/W</TD>
367<TD>&nbsp;</TD>
368</TR>
369<TR>
370<TD><TT>YPosition</TT></TD>
371<TD ALIGN=center>286</TD>
372<TD ALIGN=center>R/W</TD>
373<TD>&nbsp;</TD>
374</TR>
375<TR>
376<TD><TT>FreeOffsets</TT></TD>
377<TD ALIGN=center>288</TD>
378<TD>&nbsp;</TD>
379<TD>parsed but ignored</TD>
380</TR>
381<TR>
382<TD><TT>FreeByteCounts</TT></TD>
383<TD ALIGN=center>289</TD>
384<TD>&nbsp;</TD>
385<TD>parsed but ignored</TD>
386</TR>
387<TR>
388<TD><TT>GrayResponseUnit</TT></TD>
389<TD ALIGN=center>290</TD>
390<TD>&nbsp;</TD>
391<TD>parsed but ignored</TD>
392</TR>
393<TR>
394<TD><TT>GrayResponseCurve</TT></TD>
395<TD ALIGN=center>291</TD>
396<TD>&nbsp;</TD>
397<TD>parsed but ignored</TD>
398</TR>
399<TR>
400<TD><TT>Group3Options</TT></TD>
401<TD ALIGN=center>292</TD>
402<TD ALIGN=center>R/W</TD>
403<TD>used by Group 3 codec</TD>
404</TR>
405<TR>
406<TD><TT>Group4Options</TT></TD>
407<TD ALIGN=center>293</TD>
408<TD ALIGN=center>R/W</TD>
409<TD>&nbsp;</TD>
410</TR>
411<TR>
412<TD><TT>ResolutionUnit</TT></TD>
413<TD ALIGN=center>296</TD>
414<TD ALIGN=center>R/W</TD>
415<TD>used by Group 3 2d encoder</TD>
416</TR>
417<TR>
418<TD><TT>PageNumber</TT></TD>
419<TD ALIGN=center>297</TD>
420<TD ALIGN=center>R/W</TD>
421<TD>&nbsp;</TD>
422</TR>
423<TR>
424<TD><TT>ColorResponseUnit</TT></TD>
425<TD ALIGN=center>300</TD>
426<TD>&nbsp;</TD>
427<TD>parsed but ignored</TD>
428</TR>
429<TR>
430<TD><TT>TransferFunction</TT></TD>
431<TD ALIGN=center>301</TD>
432<TD ALIGN=center>R/W</TD>
433<TD>&nbsp;</TD>
434</TR>
435<TR>
436<TD><TT>Software</TT></TD>
437<TD ALIGN=center>305</TD>
438<TD ALIGN=center>R/W</TD>
439<TD>&nbsp;</TD>
440</TR>
441<TR>
442<TD><TT>DateTime</TT></TD>
443<TD ALIGN=center>306</TD>
444<TD ALIGN=center>R/W</TD>
445<TD>&nbsp;</TD>
446</TR>
447<TR>
448<TD><TT>Artist</TT></TD>
449<TD ALIGN=center>315</TD>
450<TD ALIGN=center>R/W</TD>
451<TD>&nbsp;</TD>
452</TR>
453<TR>
454<TD><TT>HostComputer</TT></TD>
455<TD ALIGN=center>316</TD>
456<TD ALIGN=center>R/W</TD>
457<TD>&nbsp;</TD>
458</TR>
459<TR>
460<TD><TT>Predictor</TT></TD>
461<TD ALIGN=center>317</TD>
462<TD ALIGN=center>R/W</TD>
463<TD>used by LZW codec</TD>
464</TR>
465<TR>
466<TD><TT>WhitePoint</TT></TD>
467<TD ALIGN=center>318</TD>
468<TD ALIGN=center>R/W</TD>
469<TD>&nbsp;</TD>
470</TR>
471<TR>
472<TD><TT>PrimaryChromacities</TT></TD>
473<TD ALIGN=center>319</TD>
474<TD ALIGN=center>R/W</TD>
475<TD>&nbsp;</TD>
476</TR>
477<TR>
478<TD><TT>ColorMap</TT></TD>
479<TD ALIGN=center>320</TD>
480<TD ALIGN=center>R/W</TD>
481<TD>&nbsp;</TD>
482</TR>
483<TR>
484<TD><TT>TileWidth</TT></TD>
485<TD ALIGN=center>322</TD>
486<TD ALIGN=center>R/W</TD>
487<TD>data i/o</TD>
488</TR>
489<TR>
490<TD><TT>TileLength</TT></TD>
491<TD ALIGN=center>323</TD>
492<TD ALIGN=center>R/W</TD>
493<TD>data i/o</TD>
494</TR>
495<TR>
496<TD><TT>TileOffsets</TT></TD>
497<TD ALIGN=center>324</TD>
498<TD ALIGN=center>R/W</TD>
499<TD>data i/o</TD>
500</TR>
501<TR>
502<TD><TT>TileByteCounts</TT></TD>
503<TD ALIGN=center>324</TD>
504<TD ALIGN=center>R/W</TD>
505<TD>data i/o</TD>
506</TR>
507<TR>
508<TD><TT>BadFaxLines</TT></TD>
509<TD ALIGN=center>326</TD>
510<TD ALIGN=center>R/W</TD>
511<TD>&nbsp;</TD>
512</TR>
513<TR>
514<TD><TT>CleanFaxData</TT></TD>
515<TD ALIGN=center>327</TD>
516<TD ALIGN=center>R/W</TD>
517<TD>&nbsp;</TD>
518</TR>
519<TR>
520<TD><TT>ConsecutiveBadFaxLines</TT></TD>
521<TD ALIGN=center>328</TD>
522<TD ALIGN=center>R/W</TD>
523<TD>&nbsp;</TD>
524</TR>
525<TR>
526<TD><TT>SubIFD</TT></TD>
527<TD ALIGN=center>330</TD>
528<TD ALIGN=center>R/W</TD>
529<TD>subimage descriptor support</TD>
530</TR>
531<TR>
532<TD><TT>InkSet</TT></TD>
533<TD ALIGN=center>332</TD>
534<TD ALIGN=center>R/W</TD>
535<TD>&nbsp;</TD>
536</TR>
537<TR>
538<TD><TT>InkNames</TT></TD>
539<TD ALIGN=center>333</TD>
540<TD ALIGN=center>R/W</TD>
541<TD>&nbsp;</TD>
542</TR>
543<TR>
544<TD><TT>DotRange</TT></TD>
545<TD ALIGN=center>336</TD>
546<TD ALIGN=center>R/W</TD>
547<TD>&nbsp;</TD>
548</TR>
549<TR>
550<TD><TT>TargetPrinter</TT></TD>
551<TD ALIGN=center>337</TD>
552<TD ALIGN=center>R/W</TD>
553<TD>&nbsp;</TD>
554</TR>
555<TR>
556<TD><TT>ExtraSamples</TT></TD>
557<TD ALIGN=center>338</TD>
558<TD ALIGN=center>R/W</TD>
559<TD>lots</TD>
560</TR>
561<TR>
562<TD><TT>SampleFormat</TT></TD>
563<TD ALIGN=center>339</TD>
564<TD ALIGN=center>R/W</TD>
565<TD>&nbsp;</TD>
566</TR>
567<TR>
568<TD><TT>SMinSampleValue</TT></TD>
569<TD ALIGN=center>340</TD>
570<TD ALIGN=center>R/W</TD>
571<TD>&nbsp;</TD>
572</TR>
573<TR>
574<TD><TT>SMaxSampleValue</TT></TD>
575<TD ALIGN=center>341</TD>
576<TD ALIGN=center>R/W</TD>
577<TD>&nbsp;</TD>
578</TR>
579<TR>
580<TD><TT>JPEGTables</TT></TD>
581<TD ALIGN=center>347</TD>
582<TD ALIGN=center>R/W</TD>
583<TD>used by JPEG codec</TD>
584</TR>
585<TR>
586<TD><TT>YCbCrCoefficients</TT></TD>
587<TD ALIGN=center>529</TD>
588<TD ALIGN=center>R/W</TD>
589<TD>used by <TT>TIFFReadRGBAImage</TT> support</TD>
590</TR>
591<TR>
592<TD><TT>YCbCrSubsampling</TT></TD>
593<TD ALIGN=center>530</TD>
594<TD ALIGN=center>R/W</TD>
595<TD>tile/strip size calculations</TD>
596</TR>
597<TR>
598<TD><TT>YCbCrPositioning</TT></TD>
599<TD ALIGN=center>531</TD>
600<TD ALIGN=center>R/W</TD>
601<TD>&nbsp;</TD>
602</TR>
603<TR>
604<TD><TT>ReferenceBlackWhite</TT></TD>
605<TD ALIGN=center>532</TD>
606<TD ALIGN=center>R/W</TD>
607<TD>&nbsp;</TD>
608</TR>
609<TR>
610<TD><TT>Matteing</TT></TD>
611<TD ALIGN=center>32995</TD>
612<TD ALIGN=center>R</TD>
613<TD>none (obsoleted by <TT>ExtraSamples</TT> tag)</TD>
614</TR>
615<TR>
616<TD><TT>DataType</TT></TD>
617<TD ALIGN=center>32996</TD>
618<TD ALIGN=center>R</TD>
619<TD>none (obsoleted by <TT>SampleFormat</TT> tag)</TD>
620</TR>
621<TR>
622<TD><TT>ImageDepth</TT></TD>
623<TD ALIGN=center>32997</TD>
624<TD ALIGN=center>R/W</TD>
625<TD>tile/strip calculations</TD>
626</TR>
627<TR>
628<TD><TT>TileDepth</TT></TD>
629<TD ALIGN=center>32998</TD>
630<TD ALIGN=center>R/W</TD>
631<TD>tile/strip calculations</TD>
632</TR>
633<TR>
634<TD><TT>StoNits</TT></TD>
635<TD ALIGN=center>37439</TD>
636<TD ALIGN=center>R/W</TD>
637<TD>&nbsp;</TD>
638</TR>
639</TABLE>
640
641<P>
642The <TT>Matteing</TT> and <TT>DataType</TT>
643tags have been obsoleted by the 6.0
644<TT>ExtraSamples</TT> and <TT>SampleFormat</TT> tags.
645Consult the documentation on the
646<TT>ExtraSamples</TT> tag and Associated Alpha for elaboration.  Note however
647that if you use Associated Alpha, you are expected to save data that is
648pre-multipled by Alpha.  If this means nothing to you, check out
649Porter & Duff's paper in the '84 SIGGRAPH proceedings: "Compositing Digital
650Images".
651
652<P>
653The <TT>ImageDepth</TT>
654tag is a non-standard, but registered tag that specifies
655the Z-dimension of volumetric data.  The combination of <TT>ImageWidth</TT>,
656<TT>ImageLength</TT>, and <TT>ImageDepth</TT>,
657defines a 3D volume of pixels that are
658further specified by <TT>BitsPerSample</TT> and
659<TT>SamplesPerPixel</TT>.  The <TT>TileDepth</TT>
660tag (also non-standard, but registered) can be used to specified a
661subvolume "tiling" of a volume of data.
662
663<P>
664The Colorimetry, and CMYK tags are additions that appear in TIFF 6.0.
665Consult the TIFF 6.0 specification included in the <B>doc</B> directory
666and <A HREF=document.html>online</A>.
667
668<P>
669The JPEG-related tag is specified in
670<A HREF=ftp://ftp.sgi.com/graphics/tiff/TTN2.draft.txt.gz>TIFF Technical Note #2</A> which defines
671a revised JPEG-in-TIFF scheme (revised over that appendix that was
672part of the TIFF 6.0 specification).
673
674
675
676<P>
677<HR>
678
679<ADDRESS>
680<A HREF="sam.html">Sam Leffler</A> / <A HREF="mailto:[email protected]">[email protected]</A>.
681Last updated: $Date: 1999-08-09 20:16:59 $
682</ADDRESS>
683
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686</HTML>
687