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author | Reinhard Tartler <siretart@tauware.de> | 2011-10-10 17:43:39 +0200 |
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committer | Reinhard Tartler <siretart@tauware.de> | 2011-10-10 17:43:39 +0200 |
commit | f4092abdf94af6a99aff944d6264bc1284e8bdd4 (patch) | |
tree | 2ac1c9cc16ceb93edb2c4382c088dac5aeafdf0f /nx-X11/lib/X11/Lab.c | |
parent | a840692edc9c6d19cd7c057f68e39c7d95eb767d (diff) | |
download | nx-libs-f4092abdf94af6a99aff944d6264bc1284e8bdd4.tar.gz nx-libs-f4092abdf94af6a99aff944d6264bc1284e8bdd4.tar.bz2 nx-libs-f4092abdf94af6a99aff944d6264bc1284e8bdd4.zip |
Imported nx-X11-3.1.0-1.tar.gznx-X11/3.1.0-1
Summary: Imported nx-X11-3.1.0-1.tar.gz
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Imported nx-X11-3.1.0-1.tar.gz
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Diffstat (limited to 'nx-X11/lib/X11/Lab.c')
-rw-r--r-- | nx-X11/lib/X11/Lab.c | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/nx-X11/lib/X11/Lab.c b/nx-X11/lib/X11/Lab.c new file mode 100644 index 000000000..596c137f8 --- /dev/null +++ b/nx-X11/lib/X11/Lab.c @@ -0,0 +1,416 @@ +/* $Xorg: Lab.c,v 1.3 2000/08/17 19:44:39 cpqbld Exp $ */ + +/* + * Code and supporting documentation (c) Copyright 1990 1991 Tektronix, Inc. + * All Rights Reserved + * + * This file is a component of an X Window System-specific implementation + * of XCMS based on the TekColor Color Management System. Permission is + * hereby granted to use, copy, modify, sell, and otherwise distribute this + * software and its documentation for any purpose and without fee, provided + * that this copyright, permission, and disclaimer notice is reproduced in + * all copies of this software and in supporting documentation. TekColor + * is a trademark of Tektronix, Inc. + * + * Tektronix makes no representation about the suitability of this software + * for any purpose. It is provided "as is" and with all faults. + * + * TEKTRONIX DISCLAIMS ALL WARRANTIES APPLICABLE TO THIS SOFTWARE, + * INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A + * PARTICULAR PURPOSE. IN NO EVENT SHALL TEKTRONIX BE LIABLE FOR ANY + * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER + * RESULTING FROM LOSS OF USE, DATA, OR PROFITS, WHETHER IN AN ACTION OF + * CONTRACT, NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN + * CONNECTION WITH THE USE OR THE PERFORMANCE OF THIS SOFTWARE. + * + * + * NAME + * CIELab.c + * + * DESCRIPTION + * This file contains routines that support the CIE L*a*b* + * color space to include conversions to and from the CIE + * XYZ space. These conversions are from Principles of + * Color Technology Second Edition, Fred W. Billmeyer, Jr. + * and Max Saltzman, John Wiley & Sons, Inc., 1981. + * + * Note that the range for L* is 0 to 1. + */ +/* $XFree86: xc/lib/X11/Lab.c,v 1.3 2001/01/17 19:41:38 dawes Exp $ */ + + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif +#include <X11/Xos.h> +#include <stdio.h> /* sscanf */ +#include "Xlibint.h" +#include "Xcmsint.h" +#include "Cv.h" + +/* + * DEFINES + * Internal definitions that need NOT be exported to any package + * or program using this package. + */ +#ifdef DBL_EPSILON +# define XMY_DBL_EPSILON DBL_EPSILON +#else +# define XMY_DBL_EPSILON 0.00001 +#endif +#define DIV16BY116 0.137931 + +/* + * FORWARD DECLARATIONS + */ + +static int CIELab_ParseString(register char *spec, XcmsColor *pColor); +static Status XcmsCIELab_ValidSpec(XcmsColor *pColor); + + +/* + * LOCAL VARIABLES + */ + + + /* + * NULL terminated list of functions applied to get from CIELab to CIEXYZ + */ +static XcmsConversionProc Fl_CIELab_to_CIEXYZ[] = { + XcmsCIELabToCIEXYZ, + NULL +}; + + /* + * NULL terminated list of functions applied to get from CIEXYZ to CIELab + */ +static XcmsConversionProc Fl_CIEXYZ_to_CIELab[] = { + XcmsCIEXYZToCIELab, + NULL +}; + + +/* + * GLOBALS + */ + /* + * CIE Lab Color Space + */ +XcmsColorSpace XcmsCIELabColorSpace = + { + _XcmsCIELab_prefix, /* prefix */ + XcmsCIELabFormat, /* id */ + CIELab_ParseString, /* parseString */ + Fl_CIELab_to_CIEXYZ, /* to_CIEXYZ */ + Fl_CIEXYZ_to_CIELab, /* from_CIEXYZ */ + 1 + }; + + +/************************************************************************ + * * + * PRIVATE ROUTINES * + * * + ************************************************************************/ + +/* + * NAME + * CIELab_ParseString + * + * SYNOPSIS + */ +static int +CIELab_ParseString( + register char *spec, + XcmsColor *pColor) +/* + * DESCRIPTION + * This routines takes a string and attempts to convert + * it into a XcmsColor structure with XcmsCIELabFormat. + * The assumed CIELab string syntax is: + * CIELab:<L>/<a>/<b> + * Where L, a, and b are in string input format for floats + * consisting of: + * a. an optional sign + * b. a string of numbers possibly containing a decimal point, + * c. an optional exponent field containing an 'E' or 'e' + * followed by a possibly signed integer string. + * + * RETURNS + * 0 if failed, non-zero otherwise. + */ +{ + int n; + char *pchar; + + if ((pchar = strchr(spec, ':')) == NULL) { + return(XcmsFailure); + } + n = (int)(pchar - spec); + + /* + * Check for proper prefix. + */ + if (strncmp(spec, _XcmsCIELab_prefix, n) != 0) { + return(XcmsFailure); + } + + /* + * Attempt to parse the value portion. + */ + if (sscanf(spec + n + 1, "%lf/%lf/%lf", + &pColor->spec.CIELab.L_star, + &pColor->spec.CIELab.a_star, + &pColor->spec.CIELab.b_star) != 3) { + return(XcmsFailure); + } + pColor->format = XcmsCIELabFormat; + pColor->pixel = 0; + + return(XcmsCIELab_ValidSpec(pColor)); +} + + + +/************************************************************************ + * * + * PUBLIC ROUTINES * + * * + ************************************************************************/ + +/* + * NAME + * XcmsCIELab_ValidSpec + * + * SYNOPSIS + */ +static Status +XcmsCIELab_ValidSpec( + XcmsColor *pColor) +/* + * DESCRIPTION + * Checks if color specification valid for CIE L*a*b*. + * + * RETURNS + * XcmsFailure if invalid, + * XcmsSuccess if valid. + * + */ +{ + if (pColor->format != XcmsCIELabFormat + || + (pColor->spec.CIELab.L_star < 0.0 - XMY_DBL_EPSILON) + || + (pColor->spec.CIELab.L_star > 100.0 + XMY_DBL_EPSILON)) { + return(XcmsFailure); + } + return(XcmsSuccess); +} + + +/* + * NAME + * XcmsCIELabToCIEXYZ - convert CIELab to CIEXYZ + * + * SYNOPSIS + */ +Status +XcmsCIELabToCIEXYZ(ccc, pLab_WhitePt, pColors_in_out, nColors) + XcmsCCC ccc; + XcmsColor *pLab_WhitePt; + XcmsColor *pColors_in_out; + unsigned int nColors; +/* + * DESCRIPTION + * Converts color specifications in an array of XcmsColor + * structures from CIELab format to CIEXYZ format. + * + * WARNING: This routine assumes that Yn = 1.0; + * + * RETURNS + * XcmsFailure if failed, + * XcmsSuccess if succeeded. + * + */ +{ + XcmsCIEXYZ XYZ_return; + XcmsFloat tmpFloat, tmpL; + XcmsColor whitePt; + int i; + XcmsColor *pColor = pColors_in_out; + + /* + * Check arguments + */ + if (pLab_WhitePt == NULL || pColors_in_out == NULL) { + return(XcmsFailure); + } + + /* + * Make sure white point is in CIEXYZ form, if not, convert it. + */ + if (pLab_WhitePt->format != XcmsCIEXYZFormat) { + /* Make a copy of the white point because we're going to modify it */ + memcpy((char *)&whitePt, (char *)pLab_WhitePt, sizeof(XcmsColor)); + if (!_XcmsDIConvertColors(ccc, &whitePt, + (XcmsColor *)NULL, 1, XcmsCIEXYZFormat)) { + return(XcmsFailure); + } + pLab_WhitePt = &whitePt; + } + + /* + * Make sure it is a white point, i.e., Y == 1.0 + */ + if (pLab_WhitePt->spec.CIEXYZ.Y != 1.0) { + return (0); + } + + /* + * Now convert each XcmsColor structure to CIEXYZ form + */ + for (i = 0; i < nColors; i++, pColor++) { + + /* Make sure original format is CIELab */ + if (!XcmsCIELab_ValidSpec(pColor)) { + return(XcmsFailure); + } + + /* Calculate Y: assume that Yn = 1.0 */ + tmpL = (pColor->spec.CIELab.L_star + 16.0) / 116.0; + XYZ_return.Y = tmpL * tmpL * tmpL; + + if (XYZ_return.Y < 0.008856) { + /* Calculate Y: assume that Yn = 1.0 */ + tmpL = pColor->spec.CIELab.L_star / 9.03292; + + /* Calculate X */ + XYZ_return.X = pLab_WhitePt->spec.CIEXYZ.X * + ((pColor->spec.CIELab.a_star / 3893.5) + tmpL); + /* Calculate Y */ + XYZ_return.Y = tmpL; + /* Calculate Z */ + XYZ_return.Z = pLab_WhitePt->spec.CIEXYZ.Z * + (tmpL - (pColor->spec.CIELab.b_star / 1557.4)); + } else { + /* Calculate X */ + tmpFloat = tmpL + (pColor->spec.CIELab.a_star / 5.0); + XYZ_return.X = pLab_WhitePt->spec.CIEXYZ.X * tmpFloat * tmpFloat * tmpFloat; + + /* Calculate Z */ + tmpFloat = tmpL - (pColor->spec.CIELab.b_star / 2.0); + XYZ_return.Z = pLab_WhitePt->spec.CIEXYZ.Z * tmpFloat * tmpFloat * tmpFloat; + } + + memcpy((char *)&pColor->spec.CIEXYZ, (char *)&XYZ_return, + sizeof(XcmsCIEXYZ)); + pColor->format = XcmsCIEXYZFormat; + } + + return (1); +} + + +/* + * NAME + * XcmsCIEXYZToCIELab - convert CIEXYZ to CIELab + * + * SYNOPSIS + */ +Status +XcmsCIEXYZToCIELab(ccc, pLab_WhitePt, pColors_in_out, nColors) + XcmsCCC ccc; + XcmsColor *pLab_WhitePt; + XcmsColor *pColors_in_out; + unsigned int nColors; +/* + * DESCRIPTION + * Converts color specifications in an array of XcmsColor + * structures from CIEXYZ format to CIELab format. + * + * WARNING: This routine assumes that Yn = 1.0; + * + * RETURNS + * XcmsFailure if failed, + * XcmsSuccess if succeeded. + * + */ +{ + XcmsCIELab Lab_return; + XcmsFloat fX_Xn, fY_Yn, fZ_Zn; + XcmsColor whitePt; + int i; + XcmsColor *pColor = pColors_in_out; + + /* + * Check arguments + */ + if (pLab_WhitePt == NULL || pColors_in_out == NULL) { + return(XcmsFailure); + } + + /* + * Make sure white point is in CIEXYZ form, if not, convert it. + */ + if (pLab_WhitePt->format != XcmsCIEXYZFormat) { + /* Make a copy of the white point because we're going to modify it */ + memcpy((char *)&whitePt, (char *)pLab_WhitePt, sizeof(XcmsColor)); + if (!_XcmsDIConvertColors(ccc, &whitePt, (XcmsColor *)NULL, + 1, XcmsCIEXYZFormat)) { + return(XcmsFailure); + } + pLab_WhitePt = &whitePt; + } + + /* + * Make sure it is a white point, i.e., Y == 1.0 + */ + if (pLab_WhitePt->spec.CIEXYZ.Y != 1.0) { + return(XcmsFailure); + } + + /* + * Now convert each XcmsColor structure to CIEXYZ form + */ + for (i = 0; i < nColors; i++, pColor++) { + + /* Make sure original format is CIELab */ + if (!_XcmsCIEXYZ_ValidSpec(pColor)) { + return(XcmsFailure); + } + + /* Calculate L*: assume Yn = 1.0 */ + if (pColor->spec.CIEXYZ.Y < 0.008856) { + fY_Yn = (0.07787 * pColor->spec.CIEXYZ.Y) + DIV16BY116; + /* note fY_Yn used to compute Lab_return.a below */ + Lab_return.L_star = 116.0 * (fY_Yn - DIV16BY116); + } else { + fY_Yn = (XcmsFloat)XCMS_CUBEROOT(pColor->spec.CIEXYZ.Y); + /* note fY_Yn used to compute Lab_return.a_star below */ + Lab_return.L_star = (116.0 * fY_Yn) - 16.0; + } + + /* Calculate f(X/Xn) */ + if ((fX_Xn = pColor->spec.CIEXYZ.X / pLab_WhitePt->spec.CIEXYZ.X) < 0.008856) { + fX_Xn = (0.07787 * fX_Xn) + DIV16BY116; + } else { + fX_Xn = (XcmsFloat) XCMS_CUBEROOT(fX_Xn); + } + + /* Calculate f(Z/Zn) */ + if ((fZ_Zn = pColor->spec.CIEXYZ.Z / pLab_WhitePt->spec.CIEXYZ.Z) < 0.008856) { + fZ_Zn = (0.07787 * fZ_Zn) + DIV16BY116; + } else { + fZ_Zn = (XcmsFloat) XCMS_CUBEROOT(fZ_Zn); + } + + Lab_return.a_star = 5.0 * (fX_Xn - fY_Yn); + Lab_return.b_star = 2.0 * (fY_Yn - fZ_Zn); + + memcpy((char *)&pColor->spec.CIELab, (char *)&Lab_return, + sizeof(XcmsCIELab)); + pColor->format = XcmsCIELabFormat; + } + + return(XcmsSuccess); +} |