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diff --git a/tiff/html/man/TIFFcolor.3tiff.html b/tiff/html/man/TIFFcolor.3tiff.html new file mode 100644 index 0000000..7e4eea5 --- /dev/null +++ b/tiff/html/man/TIFFcolor.3tiff.html @@ -0,0 +1,975 @@ +<!-- Creator : groff version 1.18.1 --> +<!-- CreationDate: Fri Jul 13 17:43:15 2007 --> +<html> +<head> +<meta name="generator" content="groff -Thtml, see www.gnu.org"> +<meta name="Content-Style" content="text/css"> +<title>COLOR</title> +</head> +<body> + +<h1 align=center>COLOR</h1> +<a href="#NAME">NAME</a><br> +<a href="#SYNOPSIS">SYNOPSIS</a><br> +<a href="#DESCRIPTION">DESCRIPTION</a><br> +<a href="#SEE ALSO">SEE ALSO</a><br> + +<hr> +<a name="NAME"></a> +<h2>NAME</h2> +<!-- INDENTATION --> +<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>TIFFYCbCrToRGBInit, TIFFYCbCrtoRGB, TIFFCIELabToRGBInit, +TIFFCIELabToXYZ, TIFFXYZToRGB − color conversion +routines.</p> +</td> +</table> +<a name="SYNOPSIS"></a> +<h2>SYNOPSIS</h2> +<!-- INDENTATION --> +<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><b>#include <tiffio.h></b></p> +<!-- INDENTATION --> +<p><b>int TIFFYCbCrToRGBInit(TIFFYCbCrToRGB +*</b><i>ycbcr</i><b>, float *</b><i>luma</i><b>, float +*</b><i>refBlackWhite"</i><b>);"<br> +void TIFFYCbCrtoRGB(TIFFYCbCrToRGB *</b><i>ycbcr</i><b>, +uint32</b> <i>Y</i><b>, int32</b> <i>Cb</i><b>, int32</b> +<i>Cr</i><b>, uint32 *</b><i>R</i><b>, uint32 +*</b><i>G</i><b>, uint32 *</b><i>B</i> <b>);</b></p> +<!-- INDENTATION --> +<p><b>int TIFFCIELabToRGBInit(TIFFCIELabToRGB +*</b><i>cielab</i><b>, TIFFDisplay *</b><i>display</i><b>, +float *</b><i>refWhite</i><b>);<br> +void TIFFCIELabToXYZ(TIFFCIELabToRGB *</b><i>cielab</i><b>, +uint32</b> <i>L</i><b>, int32</b> <i>a</i><b>, int32</b> +<i>b</i><b>, float *</b><i>X</i><b>, float *</b><i>Y</i><b>, +float *</b><i>Z</i><b>);<br> +void TIFFXYZToRGB(TIFFCIELabToRGB *</b><i>cielab</i><b>, +float</b> <i>X</i><b>, float</b> <i>Y</i><b>, float</b> +<i>Z"</i><b>,</b><i>uint32</i><b>*"</b><i>R</i><b>, +uint32 *</b><i>G</i><b>, uint32 *</b><i>B</i><b>);</b></p> +</td> +</table> +<a name="DESCRIPTION"></a> +<h2>DESCRIPTION</h2> +<!-- INDENTATION --> +<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>TIFF supports several color spaces for images stored in +that format. There is usually a problem of application to +handle the data properly and convert between different +colorspaces for displaying and printing purposes. To +simplify this task libtiff implements several color +conversion routines itself. In particular, these routines +used in <b>TIFFRGBAImage(3TIFF)</b> interface.</p> +<!-- INDENTATION --> +<p><b>TIFFYCbCrToRGBInit()</b> used to initialize +<i>YCbCr</i> to <i>RGB</i> conversion state. Allocating and +freeing of the <i>ycbcr</i> structure belongs to programmer. +<i>TIFFYCbCrToRGB</i> defined in <b>tiffio.h</b> as</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>typedef struct { /* YCbCr->RGB support */ + TIFFRGBValue* clamptab; /* range clamping table */ +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="5" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> + +<p>int*</p> +<td width="28%"></td> +<td width="-3%"></td> +<td width="12%"></td> +<td width="6%"> + +<p>Cr_r_tab;<br> +int*</p> +</td> +<td width="56%"> +</td> +<tr valign="top" align="left"> +<td width="28%"></td> +<td width="-3%"></td> +<td width="12%"></td> +<td width="6%"> + +<p>Cb_b_tab;<br> +int32*</p> +</td> +<td width="56%"> +</td> +<tr valign="top" align="left"> +<td width="28%"></td> +<td width="-3%"></td> +<td width="12%"></td> +<td width="6%"> + +<p>Cr_g_tab;<br> +int32*</p> +</td> +<td width="56%"> +</td> +<tr valign="top" align="left"> +<td width="28%"></td> +<td width="-3%"></td> +<td width="12%"></td> +<td width="6%"> + +<p>Cb_g_tab;</p> +</td> +<td width="56%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>int32* Y_tab;<br> +} TIFFYCbCrToRGB;</p></td> +</table> +<!-- INDENTATION --> +<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><i>luma</i> is a float array of three values representing +proportions of the red, green and blue in luminance, Y (see +section 21 of the TIFF 6.0 specification, where the YCbCr +images discussed). <i>TIFFTAG_YCBCRCOEFFICIENTS</i> holds +that values in TIFF file. <i>refBlackWhite</i> is a float +array of 6 values which specifies a pair of headroom and +footroom image data values (codes) for each image component +(see section 20 of the TIFF 6.0 specification where the +colorinmetry fields discussed). +<i>TIFFTAG_REFERENCEBLACKWHITE</i> is responsible for +storing these values in TIFF file. Following code snippet +should helps to understand the the technique:</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>float *luma, *refBlackWhite; +uint16 hs, vs; + +/* Initialize structures */ +ycbcr = (TIFFYCbCrToRGB*) +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>_TIFFmalloc(TIFFroundup(sizeof(TIFFYCbCrToRGB), +sizeof(long))</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>+ 4*256*sizeof(TIFFRGBValue)</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>+ 2*256*sizeof(int)</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>+ 3*256*sizeof(int32));</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>if (ycbcr == NULL) {<br> +TIFFError("YCbCr->RGB",</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="4" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>"No space for YCbCr->RGB conversion +state");</p> +</td> +<td width="62%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>exit(0);<br> +}</p> +<!-- INDENTATION --> +<p>TIFFGetFieldDefaulted(tif, TIFFTAG_YCBCRCOEFFICIENTS, +&luma);<br> +TIFFGetFieldDefaulted(tif, TIFFTAG_REFERENCEBLACKWHITE, +&refBlackWhite);<br> +if (TIFFYCbCrToRGBInit(ycbcr, luma, refBlackWhite) < +0)</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>exit(0);</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>/* Start conversion */<br> +uint32 r, g, b;<br> +uint32 Y;<br> +int32 Cb, Cr;</p> +<!-- INDENTATION --> +<p>for each pixel in image</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>TIFFYCbCrtoRGB(img->ycbcr, Y, Cb, Cr, &r, &g, +&b);</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>/* Free state structure */<br> +_TIFFfree(ycbcr);</p></td> +</table> +<!-- INDENTATION --> +<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><b>TIFFCIELabToRGBInit()</b> initializes the <i>CIE +L*a*b* 1976</i> to <i>RGB</i> conversion state. +<b>TIFFCIELabToRGB</b> defined as</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>#define CIELABTORGB_TABLE_RANGE 1500 + +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="9" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> + +<p>typedef struct {</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>/* CIE Lab 1976->RGB support */</p> +</td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>int</p> +</td> +<td width="6%"> + +<p>range;</p> +</td> +<td width="6%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>/* Size of conversion table */</p> +</td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>float</p> +</td> +<td width="6%"></td> +<td width="6%"> + +<p>rstep, gstep, bstep;</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>float</p> +</td> +<td width="6%"></td> +<td width="6%"> + +<p>X0, Y0, Z0;</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"> + +<p>/* Reference white point */</p> +</td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"></td> +<td width="6%"> + +<p>TIFFDisplay display;</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>float</p> +</td> +<td width="6%"></td> +<td width="6%"> + +<p>Yr2r[CIELABTORGB_TABLE_RANGE + 1]; /* Conversion of Yr +to r */</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>float</p> +</td> +<td width="6%"></td> +<td width="6%"> + +<p>Yg2g[CIELABTORGB_TABLE_RANGE + 1]; /* Conversion of Yg +to g */</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="37%"> +</td> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>float</p> +</td> +<td width="6%"></td> +<td width="6%"> + +<p>Yb2b[CIELABTORGB_TABLE_RANGE + 1]; /* Conversion of Yb +to b */</p> +</td> +<td width="6%"></td> +<td width="6%"></td> +<td width="6%"></td> +<td width="37%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>} TIFFCIELabToRGB;</p></td> +</table> +<!-- INDENTATION --> +<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><i>display</i> is a display device description, declared +as</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>typedef struct { +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_mat[3][3]; /* XYZ -> luminance matrix */</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_YCR; /* Light o/p for reference white */</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_YCG;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_YCB;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>uint32 d_Vrwr; /* Pixel values for ref. white */</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>uint32 d_Vrwg;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>uint32 d_Vrwb;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_Y0R; /* Residual light for black pixel */</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_Y0G;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_Y0B;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_gammaR; /* Gamma values for the three guns +*/</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_gammaG;</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>float d_gammaB;</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>} TIFFDisplay;</p></td> +</table> +<!-- INDENTATION --> +<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>For example, the one can use sRGB device, which has the +following parameters:</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>TIFFDisplay display_sRGB = { +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="5" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>{ /* XYZ -> luminance matrix */</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>{ 3.2410F, -1.5374F, -0.4986F },</p> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>{ -0.9692F, 1.8760F, 0.0416F },</p> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>{ 0.0556F, -0.2040F, 1.0570F }</p> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>},</p> +</td> +<td width="6%"> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>100.0F, 100.0F, 100.0F, /* Light o/p for reference white +*/</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>255, 255, 255, /* Pixel values for ref. white */</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>1.0F, 1.0F, 1.0F, /* Residual light o/p for black pixel +*/</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>2.4F, 2.4F, 2.4F, /* Gamma values for the three guns +*/</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>};</p></td> +</table> +<!-- INDENTATION --> +<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><i>refWhite</i> is a color temperature of the reference +white. The <i>TIFFTAG_WHITEPOINT</i> contains the +chromaticity of the white point of the image from where the +reference white can be calculated using following +formulae:</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>refWhite_Y = 100.0<br> +refWhite_X = whitePoint_x / whitePoint_y * refWhite_Y<br> +refWhite_Z = (1.0 - whitePoint_x - whitePoint_y) / +whitePoint_y * refWhite_X</p></td> +</table> +<!-- INDENTATION --> +<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 conversion itself performed in two steps: at the +first one we will convert <i>CIE L*a*b* 1976</i> to <i>CIE +XYZ</i> using <b>TIFFCIELabToXYZ()</b> routine, and at the +second step we will convert <i>CIE XYZ</i> to <i>RGB</i> +using <b>TIFFXYZToRGB().</b> Look at the code sample +below:</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<pre>float *whitePoint; +float refWhite[3]; + +/* Initialize structures */ +img->cielab = (TIFFCIELabToRGB *) +</pre> +</td> +</table> +<!-- TABS --> + +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>_TIFFmalloc(sizeof(TIFFCIELabToRGB));</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>if (!cielab) {</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="5" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>TIFFError("CIE L*a*b*->RGB",</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>"No space for CIE L*a*b*->RGB conversion +state.");</p> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>exit(0);</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>}</p> +<!-- INDENTATION --> +<p>TIFFGetFieldDefaulted(tif, TIFFTAG_WHITEPOINT, +&whitePoint);<br> +refWhite[1] = 100.0F;<br> +refWhite[0] = whitePoint[0] / whitePoint[1] * +refWhite[1];<br> +refWhite[2] = (1.0F - whitePoint[0] - +whitePoint[1])</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>/ whitePoint[1] * refWhite[1];</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>if (TIFFCIELabToRGBInit(cielab, &display_sRGB, +refWhite) < 0) {</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="5" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>TIFFError("CIE L*a*b*->RGB",</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> +</td> +<td width="6%"> + +<p>"Failed to initialize CIE L*a*b*->RGB conversion +state.");</p> +</td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>_TIFFfree(cielab);</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="0%"></td> +<td width="6%"> + +<p>exit(0);</p> +</td> +<td width="6%"></td> +<td width="62%"> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>}</p> +<!-- INDENTATION --> +<p>/* Now we can start to convert */<br> +uint32 r, g, b;<br> +uint32 L;<br> +int32 a, b;<br> +float X, Y, Z;</p> +<!-- INDENTATION --> +<p>for each pixel in image</p></td> +</table> +<!-- TABS --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>TIFFCIELabToXYZ(cielab, L, a, b, &X, &Y, +&Z);</p> +</td> +<tr valign="top" align="left"> +<td width="24%"></td> +<td width="75%"> + +<p>TIFFXYZToRGB(cielab, X, Y, Z, &r, &g, +&b);</p> +</td> +</table> +<!-- INDENTATION --> +<table width="100%" border=0 rules="none" frame="void" + cols="2" cellspacing="0" cellpadding="0"> +<tr valign="top" align="left"> +<td width="17%"></td> +<td width="82%"> +<p>/* Don’t forget to free the state structure */<br> +_TIFFfree(cielab);</p></td> +</table> +<a name="SEE ALSO"></a> +<h2>SEE ALSO</h2> +<!-- INDENTATION --> +<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><b>TIFFRGBAImage</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> +</html> |