xref: /libtiff-4.0.7/html/support.html (revision a446e861) 
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4TIFF 6.0 Specification Coverage
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9<IMG SRC=images/strike.gif WIDTH=128 HEIGHT=100 ALIGN=left HSPACE=6>
10TIFF 6.0 Specification Coverage
11</H1>
12
13
14<P>
15The library is capable of dealing with images that are written to
16follow the 5.0 or 6.0 TIFF spec.  There is also considerable support
17for some of the more esoteric portions of the 6.0 TIFF spec.
18
19<P>
20<TABLE BORDER CELLPADDING=3>
21
22<TR>
23<TD VALIGN=top>
24<I>Core requirements</I>
25</TD>
26<TD>
27Both <TT>"MM"</TT> and <TT>"II"</TT> byte orders are handled.
28Both packed and separated planar configuration of samples.
29Any number of samples per pixel (memory permitting).
30Any image width and height (memory permitting).
31Multiple subfiles can be read and written.
32Editing is <B>not</B> supported in that related subfiles (e.g.
33a reduced resolution version of an image) are not automatically
34updated.
35<P>
36Tags handled:
37<TT>ExtraSamples</TT>,
38<TT>ImageWidth</TT>,
39<TT>ImageLength</TT>,
40<TT>NewSubfileType</TT>,
41<TT>ResolutionUnit</TT>.
42<TT>Rowsperstrip</TT>,
43<TT>StripOffsets</TT>,
44<TT>StripByteCounts</TT>,
45<TT>XResolution</TT>,
46<TT>YResolution</TT>,
47</TD>
48</TR>
49
50<TR>
51<TD VALIGN=top><I>Tiled Images</I></TD>
52<TD><TT>TileWidth</TT>,
53    <TT>TileLength</TT>,
54    <TT>TileOffsets</TT>,
55    <TT>TileByteCounts</TT>
56</TD>
57</TR>
58
59<TD VALIGN=top><I>Image Colorimetry Information</I></TD>
60<TD><TT>WhitePoint</TT>,
61    <TT>PrimaryChromaticities</TT>,
62    <TT>TransferFunction</TT>,
63    <TT>ReferenceBlackWhite</TT>
64</TD>
65</TR>
66
67<TR>
68<TD VALIGN=top><I>Class B for bilevel images</I></TD>
69<TD><TT>SamplesPerPixel</TT> = 1<BR>
70    <TT>BitsPerSample</TT> = 1<BR>
71    <TT>Compression</TT> = 1 (none), 2 (CCITT 1D), or 32773 (PackBits)<BR>
72    <TT>PhotometricInterpretation</TT> = 0 (Min-is-White), 1 (Min-is-Black)<BR>
73</TD>
74</TR>
75
76<TR>
77<TD VALIGN=top><I>Class G for grayscale images</I></TD>
78<TD><TT>SamplesPerPixel</TT> = 1<BR>
79    <TT>BitsPerSample</TT> = 4, 8<BR>
80    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
81    <TT>PhotometricInterpretation</TT> = 0 (Min-is-White), 1 (Min-is-Black)<BR>
82</TD>
83
84</TR>
85<TR>
86<TD VALIGN=top><I>Class P for palette color images</I></TD>
87<TD><TT>SamplesPerPixel</TT> = 1<BR>
88    <TT>BitsPerSample</TT> = 1-8<BR>
89    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
90    <TT>PhotometricInterpretation</TT> = 3 (Palette RGB)<BR>
91    <TT>ColorMap</TT>
92</TD>
93</TR>
94
95<TR>
96<TD VALIGN=top><I>Class R for RGB full color images</I></TD>
97<TD><TT>SamplesPerPixel</TT> = 3<BR>
98    <TT>BitsPerSample</TT> = <8,8,8><BR>
99    <TT>PlanarConfiguration</TT> = 1, 2<BR>
100    <TT>Compression</TT> = 1 (none) 5 (LZW)<BR>
101    <TT>PhotometricInterpretation</TT> = 2 (RGB)<BR>
102</TD>
103</TR>
104
105<TR>
106<TD VALIGN=top><I>Class F for facsimile</I></TD>
107<TD>(<I>Class B tags plus...</I>)<BR>
108    <TT>Compression</TT> = 3 (CCITT Group 3), 4 (CCITT Group 4)<BR>
109    <TT>FillOrder</TT> = 1 (MSB), 2 (LSB)<BR>
110    <TT>Group3Options</TT> = 1 (2d encoding), 4 (zero fill), 5 (2d+fill)<BR>
111    <TT>ImageWidth</TT> = 1728, 2048, 2482<BR>
112    <TT>NewSubFileType</TT> = 2<BR>
113    <TT>ResolutionUnit</TT> = 2 (Inch), 3 (Centimeter)<BR>
114    <TT>PageNumber</TT>,
115    <TT>XResolution</TT>,
116    <TT>YResolution</TT>,
117    <TT>Software</TT>,
118    <TT>BadFaxLines</TT>,
119    <TT>CleanFaxData</TT>,
120    <TT>ConsecutiveBadFaxLines</TT>,
121    <TT>DateTime</TT>,
122    <TT>DocumentName</TT>,
123    <TT>ImageDescription</TT>,
124    <TT>Orientation</TT>
125</TD>
126</TR>
127
128<TD VALIGN=top><I>Class S for separated images</I></TD>
129<TD><TT>SamplesPerPixel</TT> = 4<BR>
130    <TT>PlanarConfiguration</TT> = 1, 2<BR>
131    <TT>Compression</TT> = 1 (none), 5 (LZW)<BR>
132    <TT>PhotometricInterpretation</TT> = 5 (Separated)<BR>
133    <TT>InkSet</TT> = 1 (CMYK)<BR>
134    <TT>DotRange</TT>,
135    <TT>InkNames</TT>,
136    <TT>DotRange</TT>,
137    <TT>TargetPrinter</TT>
138</TD>
139</TR>
140
141<TD VALIGN=top><I>Class Y for YCbCr images</I></TD>
142<TD><TT>SamplesPerPixel</TT> = 3<BR>
143    <TT>BitsPerSample</TT> = <8,8,8><BR>
144    <TT>PlanarConfiguration</TT> = 1, 2<BR>
145    <TT>Compression</TT> = 1 (none),  5 (LZW), 7 (JPEG)<BR>
146    <TT>PhotometricInterpretation</TT> = 6 (YCbCr)<BR>
147    <TT>YCbCrCoefficients</TT>,
148    <TT>YCbCrSubsampling</TT>,
149    <TT>YCbCrPositioning</TT><BR>
150    (<I>colorimetry info from Appendix H; see above</I>)
151</TD>
152</TR>
153
154<TR>
155<TD VALIGN=top><I>Class "JPEG" for JPEG images (per TTN2)</I></TD>
156<TD><TT>PhotometricInterpretation</TT> = 1 (grayscale), 2 (RGB), 5 (CMYK), 6 (YCbCr)<BR>
157    (<I>Class Y tags if YCbCr</I>)<BR>
158    (<I>Class S tags if CMYK</I>)<BR>
159    <TT>Compression</TT> = 7 (JPEG)<BR>
160</TD>
161</TR>
162</TABLE>
163
164<P>
165In addition, the library supports some optional compression algorithms
166that are, in some cases, of dubious value.
167
168<PRE>
169    Compression = 32766	NeXT 2-bit encoding
170    Compression = 32809	ThunderScan 4-bit encoding
171    Compression = 32909	Pixar companded 11-bit ZIP encoding
172    Compression = 32946	PKZIP-style Deflate encoding (experimental)
173    Compression = 34676	SGI 32-bit Log Luminance encoding (experimental)
174    Compression = 34677	SGI 24-bit Log Luminance encoding (experimental)
175</PRE>
176
177Note that there is no support for the JPEG-related tags defined
178in the 6.0 specification; the JPEG support is based on the post-6.0
179proposal given in TIFF Technical Note #2.
180
181<P>
182<TABLE>
183<TR>
184<TD VALIGN=top><IMG SRC="images/info.gif"></TD>
185<TD>
186<EM>
187For more information on the experimental Log Luminance encoding
188consult the materials available at
189<A HREF=http://www.sgi.com/Technology/pixformat>http://www.sgi.com/Technology/pixformat</A>.
190</EM>
191</TD>
192</TR>
193</TABLE>
194
195<P>
196The following table shows the tags that are recognized
197and how they are used by the library.  If no use is indicated,
198then the library
199reads and writes the tag, but does not use it internally.
200
201<P>
202<TABLE BORDER WIDTH=100% CELLPADDING=2>
203<TR>
204<TH ALIGN=left>Tag Name</TH> <TH>Value</TH> <TH ALIGN=center>R/W</TH> <TH ALIGN=left>Library's Use (Comments)</TH>
205</TR>
206<TR>
207<TD><TT>NewSubFileType</TT></TD>
208<TD ALIGN=center>254</TD>
209<TD ALIGN=center>R/W</TD>
210<TD>none (called <TT>SubFileType</TT> in &lt;tiff.h&gt;)</TD>
211</TR>
212<TR>
213<TD><TT>SubFileType</TT></TD>
214<TD ALIGN=center>255</TD>
215<TD ALIGN=center>R/W</TD>
216<TD>none (called <TT>OSubFileType</TT> in &lt;tiff.h&gt;)</TD>
217</TR>
218<TR>
219<TD><TT>ImageWidth</TT></TD>
220<TD ALIGN=center>256</TD>
221<TD ALIGN=center>R/W</TD>
222<TD>lots</TD>
223</TR>
224<TR>
225<TD><TT>ImageLength</TT></TD>
226<TD ALIGN=center>257</TD>
227<TD ALIGN=center>R/W</TD>
228<TD>lots</TD>
229</TR>
230<TR>
231<TD><TT>BitsPerSample</TT></TD>
232<TD ALIGN=center>258</TD>
233<TD ALIGN=center>R/W</TD>
234<TD>lots</TD>
235</TR>
236<TR>
237<TD><TT>Compression</TT></TD>
238<TD ALIGN=center>259</TD>
239<TD ALIGN=center>R/W</TD>
240<TD>to select appropriate codec</TD>
241</TR>
242<TR>
243<TD><TT>PhotometricInterpretation</TT></TD>
244<TD ALIGN=center>262</TD>
245<TD ALIGN=center>R/W</TD>
246<TD>lots</TD>
247</TR>
248<TR>
249<TD><TT>Thresholding</TT></TD>
250<TD ALIGN=center>263</TD>
251<TD ALIGN=center>R/W</TD>
252<TD>&nbsp;</TD>
253</TR>
254<TR>
255<TD><TT>CellWidth</TT></TD>
256<TD ALIGN=center>264</TD>
257<TD>&nbsp;</TD>
258<TD>parsed but ignored</TD>
259</TR>
260<TR>
261<TD><TT>CellLength</TT></TD>
262<TD ALIGN=center>265</TD>
263<TD>&nbsp;</TD>
264<TD>parsed but ignored</TD>
265</TR>
266<TR>
267<TD><TT>FillOrder</TT></TD>
268<TD ALIGN=center>266</TD>
269<TD ALIGN=center>R/W</TD>
270<TD>control bit order</TD>
271</TR>
272<TR>
273<TD><TT>DocumentName</TT></TD>
274<TD ALIGN=center>269</TD>
275<TD ALIGN=center>R/W</TD>
276<TD>&nbsp;</TD>
277</TR>
278<TR>
279<TD><TT>ImageDescription</TT></TD>
280<TD ALIGN=center>270</TD>
281<TD ALIGN=center>R/W</TD>
282<TD>&nbsp;</TD>
283</TR>
284<TR>
285<TD><TT>Make</TT></TD>
286<TD ALIGN=center>271</TD>
287<TD ALIGN=center>R/W</TD>
288<TD>&nbsp;</TD>
289</TR>
290<TR>
291<TD><TT>Model</TT></TD>
292<TD ALIGN=center>272</TD>
293<TD ALIGN=center>R/W</TD>
294<TD>&nbsp;</TD>
295</TR>
296<TR>
297<TD><TT>StripOffsets</TT></TD>
298<TD ALIGN=center>273</TD>
299<TD ALIGN=center>R/W</TD>
300<TD>data i/o</TD>
301</TR>
302<TR>
303<TD><TT>Orientation</TT></TD>
304<TD ALIGN=center>274</TD>
305<TD ALIGN=center>R/W</TD>
306<TD>&nbsp;</TD>
307</TR>
308<TR>
309<TD><TT>SamplesPerPixel</TT></TD>
310<TD ALIGN=center>277</TD>
311<TD ALIGN=center>R/W</TD>
312<TD>lots</TD>
313</TR>
314<TR>
315<TD><TT>RowsPerStrip</TT></TD>
316<TD ALIGN=center>278</TD>
317<TD ALIGN=center>R/W</TD>
318<TD>data i/o</TD>
319</TR>
320<TR>
321<TD><TT>StripByteCounts</TT></TD>
322<TD ALIGN=center>279</TD>
323<TD ALIGN=center>R/W</TD>
324<TD>data i/o</TD>
325</TR>
326<TR>
327<TD><TT>MinSampleValue</TT></TD>
328<TD ALIGN=center>280</TD>
329<TD ALIGN=center>R/W</TD>
330<TD>&nbsp;</TD>
331</TR>
332<TR>
333<TD><TT>MaxSampleValue</TT></TD>
334<TD ALIGN=center>281</TD>
335<TD ALIGN=center>R/W</TD>
336<TD>&nbsp;</TD>
337</TR>
338<TR>
339<TD><TT>XResolution</TT></TD>
340<TD ALIGN=center>282</TD>
341<TD ALIGN=center>R/W</TD>
342<TD>&nbsp;</TD>
343</TR>
344<TR>
345<TD><TT>YResolution</TT></TD>
346<TD ALIGN=center>283</TD>
347<TD ALIGN=center>R/W</TD>
348<TD>used by Group 3 2d encoder</TD>
349</TR>
350<TR>
351<TD><TT>PlanarConfiguration</TT></TD>
352<TD ALIGN=center>284</TD>
353<TD ALIGN=center>R/W</TD>
354<TD>data i/o</TD>
355</TR>
356<TR>
357<TD><TT>PageName</TT></TD>
358<TD ALIGN=center>285</TD>
359<TD ALIGN=center>R/W</TD>
360<TD>&nbsp;</TD>
361</TR>
362<TR>
363<TD><TT>XPosition</TT></TD>
364<TD ALIGN=center>286</TD>
365<TD ALIGN=center>R/W</TD>
366<TD>&nbsp;</TD>
367</TR>
368<TR>
369<TD><TT>YPosition</TT></TD>
370<TD ALIGN=center>286</TD>
371<TD ALIGN=center>R/W</TD>
372<TD>&nbsp;</TD>
373</TR>
374<TR>
375<TD><TT>FreeOffsets</TT></TD>
376<TD ALIGN=center>288</TD>
377<TD>&nbsp;</TD>
378<TD>parsed but ignored</TD>
379</TR>
380<TR>
381<TD><TT>FreeByteCounts</TT></TD>
382<TD ALIGN=center>289</TD>
383<TD>&nbsp;</TD>
384<TD>parsed but ignored</TD>
385</TR>
386<TR>
387<TD><TT>GrayResponseUnit</TT></TD>
388<TD ALIGN=center>290</TD>
389<TD>&nbsp;</TD>
390<TD>parsed but ignored</TD>
391</TR>
392<TR>
393<TD><TT>GrayResponseCurve</TT></TD>
394<TD ALIGN=center>291</TD>
395<TD>&nbsp;</TD>
396<TD>parsed but ignored</TD>
397</TR>
398<TR>
399<TD><TT>Group3Options</TT></TD>
400<TD ALIGN=center>292</TD>
401<TD ALIGN=center>R/W</TD>
402<TD>used by Group 3 codec</TD>
403</TR>
404<TR>
405<TD><TT>Group4Options</TT></TD>
406<TD ALIGN=center>293</TD>
407<TD ALIGN=center>R/W</TD>
408<TD>&nbsp;</TD>
409</TR>
410<TR>
411<TD><TT>ResolutionUnit</TT></TD>
412<TD ALIGN=center>296</TD>
413<TD ALIGN=center>R/W</TD>
414<TD>used by Group 3 2d encoder</TD>
415</TR>
416<TR>
417<TD><TT>PageNumber</TT></TD>
418<TD ALIGN=center>297</TD>
419<TD ALIGN=center>R/W</TD>
420<TD>&nbsp;</TD>
421</TR>
422<TR>
423<TD><TT>ColorResponseUnit</TT></TD>
424<TD ALIGN=center>300</TD>
425<TD>&nbsp;</TD>
426<TD>parsed but ignored</TD>
427</TR>
428<TR>
429<TD><TT>TransferFunction</TT></TD>
430<TD ALIGN=center>301</TD>
431<TD ALIGN=center>R/W</TD>
432<TD>&nbsp;</TD>
433</TR>
434<TR>
435<TD><TT>Software</TT></TD>
436<TD ALIGN=center>305</TD>
437<TD ALIGN=center>R/W</TD>
438<TD>&nbsp;</TD>
439</TR>
440<TR>
441<TD><TT>DateTime</TT></TD>
442<TD ALIGN=center>306</TD>
443<TD ALIGN=center>R/W</TD>
444<TD>&nbsp;</TD>
445</TR>
446<TR>
447<TD><TT>Artist</TT></TD>
448<TD ALIGN=center>315</TD>
449<TD ALIGN=center>R/W</TD>
450<TD>&nbsp;</TD>
451</TR>
452<TR>
453<TD><TT>HostComputer</TT></TD>
454<TD ALIGN=center>316</TD>
455<TD ALIGN=center>R/W</TD>
456<TD>&nbsp;</TD>
457</TR>
458<TR>
459<TD><TT>Predictor</TT></TD>
460<TD ALIGN=center>317</TD>
461<TD ALIGN=center>R/W</TD>
462<TD>used by LZW codec</TD>
463</TR>
464<TR>
465<TD><TT>WhitePoint</TT></TD>
466<TD ALIGN=center>318</TD>
467<TD ALIGN=center>R/W</TD>
468<TD>&nbsp;</TD>
469</TR>
470<TR>
471<TD><TT>PrimaryChromacities</TT></TD>
472<TD ALIGN=center>319</TD>
473<TD ALIGN=center>R/W</TD>
474<TD>&nbsp;</TD>
475</TR>
476<TR>
477<TD><TT>ColorMap</TT></TD>
478<TD ALIGN=center>320</TD>
479<TD ALIGN=center>R/W</TD>
480<TD>&nbsp;</TD>
481</TR>
482<TR>
483<TD><TT>TileWidth</TT></TD>
484<TD ALIGN=center>322</TD>
485<TD ALIGN=center>R/W</TD>
486<TD>data i/o</TD>
487</TR>
488<TR>
489<TD><TT>TileLength</TT></TD>
490<TD ALIGN=center>323</TD>
491<TD ALIGN=center>R/W</TD>
492<TD>data i/o</TD>
493</TR>
494<TR>
495<TD><TT>TileOffsets</TT></TD>
496<TD ALIGN=center>324</TD>
497<TD ALIGN=center>R/W</TD>
498<TD>data i/o</TD>
499</TR>
500<TR>
501<TD><TT>TileByteCounts</TT></TD>
502<TD ALIGN=center>324</TD>
503<TD ALIGN=center>R/W</TD>
504<TD>data i/o</TD>
505</TR>
506<TR>
507<TD><TT>BadFaxLines</TT></TD>
508<TD ALIGN=center>326</TD>
509<TD ALIGN=center>R/W</TD>
510<TD>&nbsp;</TD>
511</TR>
512<TR>
513<TD><TT>CleanFaxData</TT></TD>
514<TD ALIGN=center>327</TD>
515<TD ALIGN=center>R/W</TD>
516<TD>&nbsp;</TD>
517</TR>
518<TR>
519<TD><TT>ConsecutiveBadFaxLines</TT></TD>
520<TD ALIGN=center>328</TD>
521<TD ALIGN=center>R/W</TD>
522<TD>&nbsp;</TD>
523</TR>
524<TR>
525<TD><TT>SubIFD</TT></TD>
526<TD ALIGN=center>330</TD>
527<TD ALIGN=center>R/W</TD>
528<TD>subimage descriptor support</TD>
529</TR>
530<TR>
531<TD><TT>InkSet</TT></TD>
532<TD ALIGN=center>332</TD>
533<TD ALIGN=center>R/W</TD>
534<TD>&nbsp;</TD>
535</TR>
536<TR>
537<TD><TT>InkNames</TT></TD>
538<TD ALIGN=center>333</TD>
539<TD ALIGN=center>R/W</TD>
540<TD>&nbsp;</TD>
541</TR>
542<TR>
543<TD><TT>DotRange</TT></TD>
544<TD ALIGN=center>336</TD>
545<TD ALIGN=center>R/W</TD>
546<TD>&nbsp;</TD>
547</TR>
548<TR>
549<TD><TT>TargetPrinter</TT></TD>
550<TD ALIGN=center>337</TD>
551<TD ALIGN=center>R/W</TD>
552<TD>&nbsp;</TD>
553</TR>
554<TR>
555<TD><TT>ExtraSamples</TT></TD>
556<TD ALIGN=center>338</TD>
557<TD ALIGN=center>R/W</TD>
558<TD>lots</TD>
559</TR>
560<TR>
561<TD><TT>SampleFormat</TT></TD>
562<TD ALIGN=center>339</TD>
563<TD ALIGN=center>R/W</TD>
564<TD>&nbsp;</TD>
565</TR>
566<TR>
567<TD><TT>SMinSampleValue</TT></TD>
568<TD ALIGN=center>340</TD>
569<TD ALIGN=center>R/W</TD>
570<TD>&nbsp;</TD>
571</TR>
572<TR>
573<TD><TT>SMaxSampleValue</TT></TD>
574<TD ALIGN=center>341</TD>
575<TD ALIGN=center>R/W</TD>
576<TD>&nbsp;</TD>
577</TR>
578<TR>
579<TD><TT>JPEGTables</TT></TD>
580<TD ALIGN=center>347</TD>
581<TD ALIGN=center>R/W</TD>
582<TD>used by JPEG codec</TD>
583</TR>
584<TR>
585<TD><TT>YCbCrCoefficients</TT></TD>
586<TD ALIGN=center>529</TD>
587<TD ALIGN=center>R/W</TD>
588<TD>used by <TT>TIFFReadRGBAImage</TT> support</TD>
589</TR>
590<TR>
591<TD><TT>YCbCrSubsampling</TT></TD>
592<TD ALIGN=center>530</TD>
593<TD ALIGN=center>R/W</TD>
594<TD>tile/strip size calculations</TD>
595</TR>
596<TR>
597<TD><TT>YCbCrPositioning</TT></TD>
598<TD ALIGN=center>531</TD>
599<TD ALIGN=center>R/W</TD>
600<TD>&nbsp;</TD>
601</TR>
602<TR>
603<TD><TT>ReferenceBlackWhite</TT></TD>
604<TD ALIGN=center>532</TD>
605<TD ALIGN=center>R/W</TD>
606<TD>&nbsp;</TD>
607</TR>
608<TR>
609<TD><TT>Matteing</TT></TD>
610<TD ALIGN=center>32995</TD>
611<TD ALIGN=center>R</TD>
612<TD>none (obsoleted by <TT>ExtraSamples</TT> tag)</TD>
613</TR>
614<TR>
615<TD><TT>DataType</TT></TD>
616<TD ALIGN=center>32996</TD>
617<TD ALIGN=center>R</TD>
618<TD>none (obsoleted by <TT>SampleFormat</TT> tag)</TD>
619</TR>
620<TR>
621<TD><TT>ImageDepth</TT></TD>
622<TD ALIGN=center>32997</TD>
623<TD ALIGN=center>R/W</TD>
624<TD>tile/strip calculations</TD>
625</TR>
626<TR>
627<TD><TT>TileDepth</TT></TD>
628<TD ALIGN=center>32998</TD>
629<TD ALIGN=center>R/W</TD>
630<TD>tile/strip calculations</TD>
631</TR>
632<TR>
633<TD><TT>StoNits</TT></TD>
634<TD ALIGN=center>37439</TD>
635<TD ALIGN=center>R/W</TD>
636<TD>&nbsp;</TD>
637</TR>
638</TABLE>
639
640<P>
641The <TT>Matteing</TT> and <TT>DataType</TT>
642tags have been obsoleted by the 6.0
643<TT>ExtraSamples</TT> and <TT>SampleFormat</TT> tags.
644Consult the documentation on the
645<TT>ExtraSamples</TT> tag and Associated Alpha for elaboration.  Note however
646that if you use Associated Alpha, you are expected to save data that is
647pre-multipled by Alpha.  If this means nothing to you, check out
648Porter & Duff's paper in the '84 SIGGRAPH proceedings: "Compositing Digital
649Images".
650
651<P>
652The <TT>ImageDepth</TT>
653tag is a non-standard, but registered tag that specifies
654the Z-dimension of volumetric data.  The combination of <TT>ImageWidth</TT>,
655<TT>ImageLength</TT>, and <TT>ImageDepth</TT>,
656defines a 3D volume of pixels that are
657further specified by <TT>BitsPerSample</TT> and
658<TT>SamplesPerPixel</TT>.  The <TT>TileDepth</TT>
659tag (also non-standard, but registered) can be used to specified a
660subvolume "tiling" of a volume of data.
661
662<P>
663The Colorimetry, and CMYK tags are additions that appear in TIFF 6.0.
664Consult the TIFF 6.0 specification included in the <B>doc</B> directory
665and <A HREF=document.html>online</A>.
666
667<P>
668The JPEG-related tag is specified in
669<A HREF=ftp://ftp.sgi.com/graphics/tiff/TTN2.draft.txt.gz>TIFF Technical Note #2</A> which defines
670a revised JPEG-in-TIFF scheme (revised over that appendix that was
671part of the TIFF 6.0 specification).
672
673
674
675<P>
676<HR>
677
678<ADDRESS>
679<A HREF="sam.html">Sam Leffler</A> / <A HREF="mailto:[email protected]">[email protected]</A>.
680Last updated: $Date: 1999-08-09 20:14:19 $
681</ADDRESS>
682
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686