src/tiff/html/man/TIFFRGBAImage.3tiff.html

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<!-- CreationDate: Mon Mar 13 18:03:10 2006 -->
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<title>TIFFRGBAImage</title>
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<h1 align=center>TIFFRGBAImage</h1>
<a href="#NAME">NAME</a><br>
<a href="#SYNOPSIS">SYNOPSIS</a><br>
<a href="#DESCRIPTION">DESCRIPTION</a><br>
<a href="#ALTERNATE RASTER FORMATS">ALTERNATE RASTER FORMATS</a><br>
<a href="#SIMULTANEOUS RASTER STORE AND DISPLAY">SIMULTANEOUS RASTER STORE AND DISPLAY</a><br>
<a href="#SUPPORTING ADDITIONAL TIFF FORMATS">SUPPORTING ADDITIONAL TIFF FORMATS</a><br>
<a href="#NOTES">NOTES</a><br>
<a href="#RETURN VALUES">RETURN VALUES</a><br>
<a href="#DIAGNOSTICS">DIAGNOSTICS</a><br>
<a href="#SEE ALSO">SEE ALSO</a><br>

<hr>
<a name="NAME"></a>
<h2>NAME</h2>
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<td width="91%">
<p>TIFFRGBAImageOK, TIFFRGBAImageBegin, TIFFRGBAImageGet,
TIFFRGBAImageEnd &minus; read and decode an image into a
raster</p>
</td>
</table>
<a name="SYNOPSIS"></a>
<h2>SYNOPSIS</h2>
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<td width="91%">
<p><b>#include &lt;tiffio.h&gt;</b></p>
<!-- INDENTATION -->
<p><b>typedef unsigned char TIFFRGBValue; typedef struct
_TIFFRGBAImage TIFFRGBAImage;</b></p>
<!-- INDENTATION -->
<p><b>int TIFFRGBAImageOK(TIFF *</b><i>tif</i><b>, char</b>
<i>emsg[1024]</i><b>)<br>
int TIFFRGBAImageBegin(TIFFRGBAImage *</b><i>img</i><b>,
TIFF*</b> <i>tif</i><b>, int</b> <i>stopOnError</i><b>,
char</b> <i>emsg[1024]</i><b>)<br>
int TIFFRGBAImageGet(TIFFRGBAImage *</b><i>img</i><b>,
uint32*</b> <i>raster</i><b>, uint32</b> <i>width</i> <b>,
uint32</b> <i>height</i><b>)<br>
void TIFFRGBAImageEnd(TIFFRGBAImage
*</b><i>img</i><b>)</b></p>
</td>
</table>
<a name="DESCRIPTION"></a>
<h2>DESCRIPTION</h2>
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<p>The routines described here provide a high-level
interface through which <small>TIFF</small> images may be
read into memory. Images may be strip- or tile-based and
have a variety of different characteristics: bits/sample,
samples/pixel, photometric, etc. Decoding state is
encapsulated in a <i>TIFFRGBAImage</i> structure making it
possible to capture state for multiple images and quickly
switch between them. The target raster format can be
customized to a particular application&rsquo;s needs by
installing custom routines that manipulate image data
according to application requirements.</p>
<!-- INDENTATION -->
<p>The default usage for these routines is: check if an
image can be processed using <i>TIFFRGBAImageOK</i>,
construct a decoder state block using
<i>TIFFRGBAImageBegin</i>, read and decode an image into a
target raster using <i>TIFFRGBAImageGet</i>, and then
release resources using <i>TIFFRGBAImageEnd</i>.
<i>TIFFRGBAImageGet</i> can be called multiple times to
decode an image using different state parameters. If
multiple images are to be displayed and there is not enough
space for each of the decoded rasters, multiple state blocks
can be managed and then calls can be made to
<i>TIFFRGBAImageGet</i> as needed to display an image.</p>
<!-- INDENTATION -->
<p>The generated raster is assumed to be an array of
<i>width</i> times <i>height</i> 32-bit entries, where
<i>width</i> must be less than or equal to the width of the
image (<i>height</i> may be any non-zero size). If the
raster dimensions are smaller than the image, the image data
is cropped to the raster bounds. If the raster height is
greater than that of the image, then the image data are
placed in the lower part of the raster. (Note that the
raster is assume to be organized such that the pixel at
location (<i>x</i>,<i>y</i>) is
<i>raster</i>[<i>y</i>*<i>width</i>+<i>x</i>]; with the
raster origin in the <b>lower-left</b> hand corner.)</p>
<!-- INDENTATION -->
<p>Raster pixels are 8-bit packed red, green, blue, alpha
samples. The macros <i>TIFFGetR</i>, <i>TIFFGetG</i>,
<i>TIFFGetB</i>, and <i>TIFFGetA</i> should be used to
access individual samples. Images without Associated Alpha
matting information have a constant Alpha of 1.0 (255).</p>
<!-- INDENTATION -->
<p><i>TIFFRGBAImageGet</i> converts non-8-bit images by
scaling sample values. Palette, grayscale, bilevel,
<small>CMYK</small> , and YCbCr images are converted to
<small>RGB</small> transparently. Raster pixels are returned
uncorrected by any colorimetry information present in the
directory.</p>
<!-- INDENTATION -->
<p>The parameter <i>stopOnError</i> specifies how to act if
an error is encountered while reading the image. If
<i>stopOnError</i> is non-zero, then an error will terminate
the operation; otherwise <i>TIFFRGBAImageGet</i> will
continue processing data until all the possible data in the
image have been requested.</p>
</td>
</table>
<a name="ALTERNATE RASTER FORMATS"></a>
<h2>ALTERNATE RASTER FORMATS</h2>
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       cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>To use the core support for reading and processing
<small>TIFF</small> images, but write the resulting raster
data in a different format one need only override the
&lsquo;&lsquo;<i>put methods</i>&rsquo;&rsquo; used to store
raster data. These methods are are defined in the
<i>TIFFRGBAImage</i> structure and initially setup by
<i>TIFFRGBAImageBegin</i> to point to routines that pack
raster data in the default <small>ABGR</small> pixel format.
Two different routines are used according to the physical
organization of the image data in the file:
<i>PlanarConfiguration</i>=1 (packed samples), and
<i>PlanarConfiguration</i>=2 (separated samples). Note that
this mechanism can be used to transform the data before
storing it in the raster. For example one can convert data
to colormap indices for display on a colormap display.</p>
</td>
</table>
<a name="SIMULTANEOUS RASTER STORE AND DISPLAY"></a>
<h2>SIMULTANEOUS RASTER STORE AND DISPLAY</h2>
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       cols="2" cellspacing="0" cellpadding="0">
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<td width="8%"></td>
<td width="91%">
<p>It is simple to display an image as it is being read into
memory by overriding the put methods as described above for
supporting alternate raster formats. Simply keep a reference
to the default put methods setup by
<i>TIFFRGBAImageBegin</i> and then invoke them before or
after each display operation. For example, the
<i>tiffgt</i>(1) utility uses the following put method to
update the display as the raster is being filled:</p>
<!-- INDENTATION -->
<pre>static void
putContigAndDraw(TIFFRGBAImage* img, uint32* raster,
    uint32 x, uint32 y, uint32 w, uint32 h,
    int32 fromskew, int32 toskew,
    unsigned char* cp)
{
    (*putContig)(img, raster, x, y, w, h, fromskew, toskew, cp);
    if (x+w == width) {
     w = width;
     if (img-&gt;orientation == ORIENTATION_TOPLEFT)
         lrectwrite(0, y-(h-1), w-1, y, raster-x-(h-1)*w);
     else
         lrectwrite(0, y, w-1, y+h-1, raster);
    }
}
</pre>
<!-- INDENTATION -->
<p>(the original routine provided by the library is saved in
the variable <i>putContig</i>.)</p>
</td>
</table>
<a name="SUPPORTING ADDITIONAL TIFF FORMATS"></a>
<h2>SUPPORTING ADDITIONAL TIFF FORMATS</h2>
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<table width="100%" border=0 rules="none" frame="void"
       cols="2" cellspacing="0" cellpadding="0">
<tr valign="top" align="left">
<td width="8%"></td>
<td width="91%">
<p>The <i>TIFFRGBAImage</i> routines support the most
commonly encountered flavors of <small>TIFF.</small> It is
possible to extend this support by overriding the
&lsquo;&lsquo;<i>get method</i>&rsquo;&rsquo; invoked by
<i>TIFFRGBAImageGet</i> to read <small>TIFF</small> image
data. Details of doing this are a bit involved, it is best
to make a copy of an existing get method and modify it to
suit the needs of an application.</p>
</td>
</table>
<a name="NOTES"></a>
<h2>NOTES</h2>
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<p>Samples must be either 1, 2, 4, 8, or 16 bits.
Colorimetric samples/pixel must be either 1, 3, or 4 (i.e.
<i>SamplesPerPixel</i> minus <i>ExtraSamples</i>).</p>
<!-- INDENTATION -->
<p>Palette image colormaps that appear to be incorrectly
written as 8-bit values are automatically scaled to
16-bits.</p>
</td>
</table>
<a name="RETURN VALUES"></a>
<h2>RETURN VALUES</h2>
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<p>All routines return 1 if the operation was successful.
Otherwise, 0 is returned if an error was encountered and
<i>stopOnError</i> is zero.</p>
</td>
</table>
<a name="DIAGNOSTICS"></a>
<h2>DIAGNOSTICS</h2>
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<p>All error messages are directed to the
<i>TIFFError</i>(3TIFF) routine.</p>
<!-- INDENTATION -->
<p><b>Sorry, can not handle %d-bit pictures</b>. The image
had <i>BitsPerSample</i> other than 1, 2, 4, 8, or 16.</p>
<!-- INDENTATION -->
<p><b>Sorry, can not handle %d-channel images</b>. The image
had <i>SamplesPerPixel</i> other than 1, 3, or 4.</p>
<!-- INDENTATION -->
<p><b>Missing needed &quot;PhotometricInterpretation&quot;
tag</b>. The image did not have a tag that describes how to
display the data.</p>
<!-- INDENTATION -->
<p><b>No &quot;PhotometricInterpretation&quot; tag, assuming
RGB</b>. The image was missing a tag that describes how to
display it, but because it has 3 or 4 samples/pixel, it is
assumed to be <small>RGB.</small></p>
<!-- INDENTATION -->
<p><b>No &quot;PhotometricInterpretation&quot; tag, assuming
min-is-black</b>. The image was missing a tag that describes
how to display it, but because it has 1 sample/pixel, it is
assumed to be a grayscale or bilevel image.</p>
<!-- INDENTATION -->
<p><b>No space for photometric conversion table</b>. There
was insufficient memory for a table used to convert image
samples to 8-bit <small>RGB.</small></p>
<!-- INDENTATION -->
<p><b>Missing required &quot;Colormap&quot; tag</b>. A
Palette image did not have a required <i>Colormap</i>
tag.</p>
<!-- INDENTATION -->
<p><b>No space for tile buffer</b>. There was insufficient
memory to allocate an i/o buffer.</p>
<!-- INDENTATION -->
<p><b>No space for strip buffer</b>. There was insufficient
memory to allocate an i/o buffer.</p>
<!-- INDENTATION -->
<p><b>Can not handle format</b>. The image has a format
(combination of <i>BitsPerSample</i>,
<i>SamplesPerPixel</i>, and
<i>PhotometricInterpretation</i>) that can not be
handled.</p>
<!-- INDENTATION -->
<p><b>No space for B&amp;W mapping table</b>. There was
insufficient memory to allocate a table used to map
grayscale data to <small>RGB.</small></p>
<!-- INDENTATION -->
<p><b>No space for Palette mapping table</b>. There was
insufficient memory to allocate a table used to map data to
8-bit <small>RGB.</small></p>
</td>
</table>
<a name="SEE ALSO"></a>
<h2>SEE ALSO</h2>
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<td width="91%">
<p><b>TIFFOpen</b>(3TIFF), <b>TIFFReadRGBAImage</b>(3TIFF),
<b>TIFFReadRGBAImageOriented</b>(3TIFF),
<b>TIFFReadRGBAStrip</b>(3TIFF),
<b>TIFFReadRGBATile</b>(3TIFF), <b>libtiff</b>(3TIFF)</p>
<!-- INDENTATION -->
<p>Libtiff library home page:
<b>http://www.remotesensing.org/libtiff/</b></p>
</td>
</table>
<hr>
</body>
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Commit	Line	Data
	1	<!-- Creator : groff version 1.18.1 -->
	2	<!-- CreationDate: Mon Mar 13 18:03:10 2006 -->
	3	<html>
	4	<head>
	5	<meta name="generator" content="groff -Thtml, see www.gnu.org">
	6	<meta name="Content-Style" content="text/css">
	7	<title>TIFFRGBAImage</title>
	8	</head>
	9	<body>
	10
	11	<h1 align=center>TIFFRGBAImage</h1>
	12	<a href="#NAME">NAME</a><br>
	13	<a href="#SYNOPSIS">SYNOPSIS</a><br>
	14	<a href="#DESCRIPTION">DESCRIPTION</a><br>
	15	<a href="#ALTERNATE RASTER FORMATS">ALTERNATE RASTER FORMATS</a><br>
	16	<a href="#SIMULTANEOUS RASTER STORE AND DISPLAY">SIMULTANEOUS RASTER STORE AND DISPLAY</a><br>
	17	<a href="#SUPPORTING ADDITIONAL TIFF FORMATS">SUPPORTING ADDITIONAL TIFF FORMATS</a><br>
	18	<a href="#NOTES">NOTES</a><br>
	19	<a href="#RETURN VALUES">RETURN VALUES</a><br>
	20	<a href="#DIAGNOSTICS">DIAGNOSTICS</a><br>
	21	<a href="#SEE ALSO">SEE ALSO</a><br>
	22
	23	<hr>
	24	<a name="NAME"></a>
	25	<h2>NAME</h2>
	26	<!-- INDENTATION -->
	27	<table width="100%" border=0 rules="none" frame="void"
	28	cols="2" cellspacing="0" cellpadding="0">
	29	<tr valign="top" align="left">
	30	<td width="8%"></td>
	31	<td width="91%">
	32	<p>TIFFRGBAImageOK, TIFFRGBAImageBegin, TIFFRGBAImageGet,
	33	TIFFRGBAImageEnd − read and decode an image into a
	34	raster</p>
	35	</td>
	36	</table>
	37	<a name="SYNOPSIS"></a>
	38	<h2>SYNOPSIS</h2>
	39	<!-- INDENTATION -->
	40	<table width="100%" border=0 rules="none" frame="void"
	41	cols="2" cellspacing="0" cellpadding="0">
	42	<tr valign="top" align="left">
	43	<td width="8%"></td>
	44	<td width="91%">
	45	<p><b>#include <tiffio.h></b></p>
	46	<!-- INDENTATION -->
	47	<p><b>typedef unsigned char TIFFRGBValue; typedef struct
	48	_TIFFRGBAImage TIFFRGBAImage;</b></p>
	49	<!-- INDENTATION -->
	50	<p><b>int TIFFRGBAImageOK(TIFF *</b><i>tif</i><b>, char</b>
	51	<i>emsg[1024]</i><b>)<br>
	52	int TIFFRGBAImageBegin(TIFFRGBAImage *</b><i>img</i><b>,
	53	TIFF*</b> <i>tif</i><b>, int</b> <i>stopOnError</i><b>,
	54	char</b> <i>emsg[1024]</i><b>)<br>
	55	int TIFFRGBAImageGet(TIFFRGBAImage *</b><i>img</i><b>,
	56	uint32*</b> <i>raster</i><b>, uint32</b> <i>width</i> <b>,
	57	uint32</b> <i>height</i><b>)<br>
	58	void TIFFRGBAImageEnd(TIFFRGBAImage
	59	*</b><i>img</i><b>)</b></p>
	60	</td>
	61	</table>
	62	<a name="DESCRIPTION"></a>
	63	<h2>DESCRIPTION</h2>
	64	<!-- INDENTATION -->
	65	<table width="100%" border=0 rules="none" frame="void"
	66	cols="2" cellspacing="0" cellpadding="0">
	67	<tr valign="top" align="left">
	68	<td width="8%"></td>
	69	<td width="91%">
	70	<p>The routines described here provide a high-level
	71	interface through which <small>TIFF</small> images may be
	72	read into memory. Images may be strip- or tile-based and
	73	have a variety of different characteristics: bits/sample,
	74	samples/pixel, photometric, etc. Decoding state is
	75	encapsulated in a <i>TIFFRGBAImage</i> structure making it
	76	possible to capture state for multiple images and quickly
	77	switch between them. The target raster format can be
	78	customized to a particular application’s needs by
	79	installing custom routines that manipulate image data
	80	according to application requirements.</p>
	81	<!-- INDENTATION -->
	82	<p>The default usage for these routines is: check if an
	83	image can be processed using <i>TIFFRGBAImageOK</i>,
	84	construct a decoder state block using
	85	<i>TIFFRGBAImageBegin</i>, read and decode an image into a
	86	target raster using <i>TIFFRGBAImageGet</i>, and then
	87	release resources using <i>TIFFRGBAImageEnd</i>.
	88	<i>TIFFRGBAImageGet</i> can be called multiple times to
	89	decode an image using different state parameters. If
	90	multiple images are to be displayed and there is not enough
	91	space for each of the decoded rasters, multiple state blocks
	92	can be managed and then calls can be made to
	93	<i>TIFFRGBAImageGet</i> as needed to display an image.</p>
	94	<!-- INDENTATION -->
	95	<p>The generated raster is assumed to be an array of
	96	<i>width</i> times <i>height</i> 32-bit entries, where
	97	<i>width</i> must be less than or equal to the width of the
	98	image (<i>height</i> may be any non-zero size). If the
	99	raster dimensions are smaller than the image, the image data
	100	is cropped to the raster bounds. If the raster height is
	101	greater than that of the image, then the image data are
	102	placed in the lower part of the raster. (Note that the
	103	raster is assume to be organized such that the pixel at
	104	location (<i>x</i>,<i>y</i>) is
	105	<i>raster</i>[<i>y</i>*<i>width</i>+<i>x</i>]; with the
	106	raster origin in the <b>lower-left</b> hand corner.)</p>
	107	<!-- INDENTATION -->
	108	<p>Raster pixels are 8-bit packed red, green, blue, alpha
	109	samples. The macros <i>TIFFGetR</i>, <i>TIFFGetG</i>,
	110	<i>TIFFGetB</i>, and <i>TIFFGetA</i> should be used to
	111	access individual samples. Images without Associated Alpha
	112	matting information have a constant Alpha of 1.0 (255).</p>
	113	<!-- INDENTATION -->
	114	<p><i>TIFFRGBAImageGet</i> converts non-8-bit images by
	115	scaling sample values. Palette, grayscale, bilevel,
	116	<small>CMYK</small> , and YCbCr images are converted to
	117	<small>RGB</small> transparently. Raster pixels are returned
	118	uncorrected by any colorimetry information present in the
	119	directory.</p>
	120	<!-- INDENTATION -->
	121	<p>The parameter <i>stopOnError</i> specifies how to act if
	122	an error is encountered while reading the image. If
	123	<i>stopOnError</i> is non-zero, then an error will terminate
	124	the operation; otherwise <i>TIFFRGBAImageGet</i> will
	125	continue processing data until all the possible data in the
	126	image have been requested.</p>
	127	</td>
	128	</table>
	129	<a name="ALTERNATE RASTER FORMATS"></a>
	130	<h2>ALTERNATE RASTER FORMATS</h2>
	131	<!-- INDENTATION -->
	132	<table width="100%" border=0 rules="none" frame="void"
	133	cols="2" cellspacing="0" cellpadding="0">
	134	<tr valign="top" align="left">
	135	<td width="8%"></td>
	136	<td width="91%">
	137	<p>To use the core support for reading and processing
	138	<small>TIFF</small> images, but write the resulting raster
	139	data in a different format one need only override the
	140	‘‘<i>put methods</i>’’ used to store
	141	raster data. These methods are are defined in the
	142	<i>TIFFRGBAImage</i> structure and initially setup by
	143	<i>TIFFRGBAImageBegin</i> to point to routines that pack
	144	raster data in the default <small>ABGR</small> pixel format.
	145	Two different routines are used according to the physical
	146	organization of the image data in the file:
	147	<i>PlanarConfiguration</i>=1 (packed samples), and
	148	<i>PlanarConfiguration</i>=2 (separated samples). Note that
	149	this mechanism can be used to transform the data before
	150	storing it in the raster. For example one can convert data
	151	to colormap indices for display on a colormap display.</p>
	152	</td>
	153	</table>
	154	<a name="SIMULTANEOUS RASTER STORE AND DISPLAY"></a>
	155	<h2>SIMULTANEOUS RASTER STORE AND DISPLAY</h2>
	156	<!-- INDENTATION -->
	157	<table width="100%" border=0 rules="none" frame="void"
	158	cols="2" cellspacing="0" cellpadding="0">
	159	<tr valign="top" align="left">
	160	<td width="8%"></td>
	161	<td width="91%">
	162	<p>It is simple to display an image as it is being read into
	163	memory by overriding the put methods as described above for
	164	supporting alternate raster formats. Simply keep a reference
	165	to the default put methods setup by
	166	<i>TIFFRGBAImageBegin</i> and then invoke them before or
	167	after each display operation. For example, the
	168	<i>tiffgt</i>(1) utility uses the following put method to
	169	update the display as the raster is being filled:</p>
	170	<!-- INDENTATION -->
	171	<pre>static void
	172	putContigAndDraw(TIFFRGBAImage* img, uint32* raster,
	173	uint32 x, uint32 y, uint32 w, uint32 h,
	174	int32 fromskew, int32 toskew,
	175	unsigned char* cp)
	176	{
	177	(*putContig)(img, raster, x, y, w, h, fromskew, toskew, cp);
	178	if (x+w == width) {
	179	w = width;
	180	if (img->orientation == ORIENTATION_TOPLEFT)
	181	lrectwrite(0, y-(h-1), w-1, y, raster-x-(h-1)*w);
	182	else
	183	lrectwrite(0, y, w-1, y+h-1, raster);
	184	}
	185	}
	186	</pre>
	187	<!-- INDENTATION -->
	188	<p>(the original routine provided by the library is saved in
	189	the variable <i>putContig</i>.)</p>
	190	</td>
	191	</table>
	192	<a name="SUPPORTING ADDITIONAL TIFF FORMATS"></a>
	193	<h2>SUPPORTING ADDITIONAL TIFF FORMATS</h2>
	194	<!-- INDENTATION -->
	195	<table width="100%" border=0 rules="none" frame="void"
	196	cols="2" cellspacing="0" cellpadding="0">
	197	<tr valign="top" align="left">
	198	<td width="8%"></td>
	199	<td width="91%">
	200	<p>The <i>TIFFRGBAImage</i> routines support the most
	201	commonly encountered flavors of <small>TIFF.</small> It is
	202	possible to extend this support by overriding the
	203	‘‘<i>get method</i>’’ invoked by
	204	<i>TIFFRGBAImageGet</i> to read <small>TIFF</small> image
	205	data. Details of doing this are a bit involved, it is best
	206	to make a copy of an existing get method and modify it to
	207	suit the needs of an application.</p>
	208	</td>
	209	</table>
	210	<a name="NOTES"></a>
	211	<h2>NOTES</h2>
	212	<!-- INDENTATION -->
	213	<table width="100%" border=0 rules="none" frame="void"
	214	cols="2" cellspacing="0" cellpadding="0">
	215	<tr valign="top" align="left">
	216	<td width="8%"></td>
	217	<td width="91%">
	218	<p>Samples must be either 1, 2, 4, 8, or 16 bits.
	219	Colorimetric samples/pixel must be either 1, 3, or 4 (i.e.
	220	<i>SamplesPerPixel</i> minus <i>ExtraSamples</i>).</p>
	221	<!-- INDENTATION -->
	222	<p>Palette image colormaps that appear to be incorrectly
	223	written as 8-bit values are automatically scaled to
	224	16-bits.</p>
	225	</td>
	226	</table>
	227	<a name="RETURN VALUES"></a>
	228	<h2>RETURN VALUES</h2>
	229	<!-- INDENTATION -->
	230	<table width="100%" border=0 rules="none" frame="void"
	231	cols="2" cellspacing="0" cellpadding="0">
	232	<tr valign="top" align="left">
	233	<td width="8%"></td>
	234	<td width="91%">
	235	<p>All routines return 1 if the operation was successful.
	236	Otherwise, 0 is returned if an error was encountered and
	237	<i>stopOnError</i> is zero.</p>
	238	</td>
	239	</table>
	240	<a name="DIAGNOSTICS"></a>
	241	<h2>DIAGNOSTICS</h2>
	242	<!-- INDENTATION -->
	243	<table width="100%" border=0 rules="none" frame="void"
	244	cols="2" cellspacing="0" cellpadding="0">
	245	<tr valign="top" align="left">
	246	<td width="8%"></td>
	247	<td width="91%">
	248	<p>All error messages are directed to the
	249	<i>TIFFError</i>(3TIFF) routine.</p>
	250	<!-- INDENTATION -->
	251	<p><b>Sorry, can not handle %d-bit pictures</b>. The image
	252	had <i>BitsPerSample</i> other than 1, 2, 4, 8, or 16.</p>
	253	<!-- INDENTATION -->
	254	<p><b>Sorry, can not handle %d-channel images</b>. The image
	255	had <i>SamplesPerPixel</i> other than 1, 3, or 4.</p>
	256	<!-- INDENTATION -->
	257	<p><b>Missing needed "PhotometricInterpretation"
	258	tag</b>. The image did not have a tag that describes how to
	259	display the data.</p>
	260	<!-- INDENTATION -->
	261	<p><b>No "PhotometricInterpretation" tag, assuming
	262	RGB</b>. The image was missing a tag that describes how to
	263	display it, but because it has 3 or 4 samples/pixel, it is
	264	assumed to be <small>RGB.</small></p>
	265	<!-- INDENTATION -->
	266	<p><b>No "PhotometricInterpretation" tag, assuming
	267	min-is-black</b>. The image was missing a tag that describes
	268	how to display it, but because it has 1 sample/pixel, it is
	269	assumed to be a grayscale or bilevel image.</p>
	270	<!-- INDENTATION -->
	271	<p><b>No space for photometric conversion table</b>. There
	272	was insufficient memory for a table used to convert image
	273	samples to 8-bit <small>RGB.</small></p>
	274	<!-- INDENTATION -->
	275	<p><b>Missing required "Colormap" tag</b>. A
	276	Palette image did not have a required <i>Colormap</i>
	277	tag.</p>
	278	<!-- INDENTATION -->
	279	<p><b>No space for tile buffer</b>. There was insufficient
	280	memory to allocate an i/o buffer.</p>
	281	<!-- INDENTATION -->
	282	<p><b>No space for strip buffer</b>. There was insufficient
	283	memory to allocate an i/o buffer.</p>
	284	<!-- INDENTATION -->
	285	<p><b>Can not handle format</b>. The image has a format
	286	(combination of <i>BitsPerSample</i>,
	287	<i>SamplesPerPixel</i>, and
	288	<i>PhotometricInterpretation</i>) that can not be
	289	handled.</p>
	290	<!-- INDENTATION -->
	291	<p><b>No space for B&W mapping table</b>. There was
	292	insufficient memory to allocate a table used to map
	293	grayscale data to <small>RGB.</small></p>
	294	<!-- INDENTATION -->
	295	<p><b>No space for Palette mapping table</b>. There was
	296	insufficient memory to allocate a table used to map data to
	297	8-bit <small>RGB.</small></p>
	298	</td>
	299	</table>
	300	<a name="SEE ALSO"></a>
	301	<h2>SEE ALSO</h2>
	302	<!-- INDENTATION -->
	303	<table width="100%" border=0 rules="none" frame="void"
	304	cols="2" cellspacing="0" cellpadding="0">
	305	<tr valign="top" align="left">
	306	<td width="8%"></td>
	307	<td width="91%">
	308	<p><b>TIFFOpen</b>(3TIFF), <b>TIFFReadRGBAImage</b>(3TIFF),
	309	<b>TIFFReadRGBAImageOriented</b>(3TIFF),
	310	<b>TIFFReadRGBAStrip</b>(3TIFF),
	311	<b>TIFFReadRGBATile</b>(3TIFF), <b>libtiff</b>(3TIFF)</p>
	312	<!-- INDENTATION -->
	313	<p>Libtiff library home page:
	314	<b>http://www.remotesensing.org/libtiff/</b></p>
	315	</td>
	316	</table>
	317	<hr>
	318	</body>
	319	</html>