Add YES colour model, generate the conversion matrices, and add more direct conversions

Signed-off-by: Mattias Andrée <maandree@kth.se>

11 files changed, 299 insertions, 247 deletions

diff --git a/.gitignore b/.gitignore
index f0c9d82..8c18ccb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,5 +9,7 @@
 *.so.*
 *.so
 *.a
+/__pycache__/
 /test
 /libcolour.7
+/conversion-matrices.h
diff --git a/Makefile b/Makefile
index 3c55d18..b7b78c3 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,8 @@ OBJ =\
 HDR =\
 	libcolour.h\
 	common.h\
-	conversions.h
+	conversions.h\
+	conversion-matrices.h
 
 TEMPLATES =\
 	en_masse-template.c\
@@ -80,6 +81,11 @@ MAN3_SYMLINKS =\
 all: libcolour.a libcolour.so.$(SO_VERSION) libcolour.7 test
 
 
+conversion-matrices.h: matrices.py
+	printf '/* This file is generated! */\n' > conversion-matrices.h
+	./matrices.py >> conversion-matrices.h
+
+
 float.o: float.c $(TEMPLATES) $(HDR)
 	$(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ float.c
 
@@ -179,6 +185,6 @@ check: test
 	./test
 
 clean:
-	-rm -- *.o *.a *.so *.so.* test
+	-rm -- *.o *.a *.so *.so.* test conversion-matrices.h
 
 .PHONY: all clean check install uninstall
diff --git a/TODO b/TODO
index 407bbda..5e0eecd 100644
--- a/TODO
+++ b/TODO
@@ -7,7 +7,7 @@ Colour models and colour spaces:
 	TSL
 	Y'UV
 	Y'IQ
-	YES
+	Y'ES
 	rgY
 	RGK
 	CIE DSH
diff --git a/conversions.h b/conversions.h
index 99261e9..494a666 100644
--- a/conversions.h
+++ b/conversions.h
@@ -12,25 +12,6 @@
 	(TO_MINV)[1][0], (TO_MINV)[1][1], (TO_MINV)[1][2],\
 	(TO_MINV)[2][0], (TO_MINV)[2][1], (TO_MINV)[2][2]
 
-#define CIEXYZ_TO_SRGB\
-	MATRIX( 3.240446254647737500675930277794, -1.537134761820080575134284117667, -0.498530193022728718155178739835,\
-	       -0.969266606244679751469561779231,  1.876011959788370209167851498933,  0.041556042214430065351304932619,\
-	        0.055643503564352832235773149705, -0.204026179735960239147729566866,  1.057226567722703292062647051353)
-
-#define YIQ_TO_SRGB\
-	MATRIX(1.,  0.95629483232089407263032398986979387700557708740234,  0.62102512544472865396727456754888407886028289794922,\
-	       1., -0.27212147408397735492968649850809015333652496337891, -0.64738095351761570928061928498209454119205474853516,\
-	       1., -1.10698990856712820018969978264067322015762329101562,  1.70461497549882934343656870623817667365074157714844)
-	/* ⎛1    1000 cos 33° / 877                                  1000 sin 33° / 877                               ⎞
-	   ⎜1    9500 sin 33° / 24067 - 299000 * cos 33° / 514799    -9500 cos 33° / 24067 - 299000 * sin 33° / 514799⎟
-	   ⎝1    -250 sin 33° / 123                                  250 cos 33° / 123                                ⎠
-	*/
-
-#define YDBDR_TO_SRGB\
-	MATRIX(1.,  0.000092303716148, -0.525912630661865,\
-	       1., -0.129132898890509,  0.267899328207599,\
-	       1.,  0.664679059978955, -0.000079202543533)
-
 #define YPBPR_TO_SRGB(FROM_Y, FROM_PB, FROM_PR, TO_R, TO_G, TO_B)\
 	do {\
 		TYPE y__ = (FROM_Y);\
@@ -41,16 +22,6 @@
 		(TO_G) = (y__ - r__ * D(0.2126) - b__ * D(0.0722)) / D(0.7152);\
 	} while (0)
 
-#define YUV_TO_SRGB\
-	MATRIX(1.,  0.00028328010485821202317155420580263580632163211703,  1.14070449590558520291949662350816652178764343261719,\
-	       1., -0.39630886669497211727275498560629785060882568359375, -0.58107364288228224857846271333983168005943298339844,\
-	       1.,  2.03990003507541306504435851820744574069976806640625,  0.00017179031692307700847528739718228507626918144524)
-
-#define YCGCO_TO_SRGB\
-	MATRIX(1., -1.,  1.,\
-	       1.,  1.,  0.,\
-	       1., -1., -1.)
-
 #define CIEXYZ_TO_CIEXYY(FROM_X, FROM_Y, FROM_Z, TO_X, TO_Y, TO_YY)\
 	do {\
 		TYPE x__ = (FROM_X), y__ = (FROM_Y), z__ = (FROM_Z);\
@@ -69,11 +40,6 @@
 	(FROM_M)[1][0], (FROM_M)[1][1], (FROM_M)[1][2],\
 	(FROM_M)[2][0], (FROM_M)[2][1], (FROM_M)[2][2]
 
-#define SRGB_TO_CIEXYZ\
-	MATRIX(0.412457445582367576708548995157, 0.357575865245515878143578447634, 0.180437247826399665973085006954,\
-	       0.212673370378408277403536885686, 0.715151730491031756287156895269, 0.072174899130559869164791564344,\
-	       0.019333942761673460208893260415, 0.119191955081838593666354597644, 0.950302838552371742508739771438)
-
 #define CIEXYY_TO_CIEXYZ(FROM_X, FROM_Y, FROM_YY, TO_X, TO_Y, TO_Z)\
 	do {\
 		TYPE x__ = (FROM_X), y__ = (FROM_Y), Y__ = (FROM_YY);\
@@ -115,61 +81,6 @@
 		(TO_Z) = Y__ * (3 / v__ - D(0.75) * u__ / v__ - 5);\
 	} while (0)
 
-#define YIQ_TO_CIEXYZ\
-	MATRIX( 0.95047055865428309306963683411595411598682403564453,\
-	        0.09738463974178063198294807989441324025392532348633,\
-	        0.33223466706854809515903070860076695680618286132812,\
-	        0.99999999999999988897769753748434595763683319091797,\
-	       -0.07112658301916767455974621725545148365199565887451,\
-	       -0.20786968876398304040264974901219829916954040527344,\
-	        1.08882873639588373393394249433185905218124389648438,\
-	       -1.06592139332461721679123911599162966012954711914062,\
-	        1.55474471255181900808395312196807935833930969238281)
-
-#define YDBDR_TO_CIEXYZ\
-	MATRIX( 0.95047055865428309306963683411595411598682403564453,\
-	        0.07379612357298576119646327242662664502859115600586,\
-	       -0.12113653724874726136384595065464964136481285095215,\
-	        0.99999999999999988897769753748434595763683319091797,\
-	       -0.04435684145428285540813106990754022262990474700928,\
-	        0.07973534004202506575431641522300196811556816101074,\
-	        1.08882873639588373393394249433185905218124389648438,\
-	        0.61625657933494271123464613992837257683277130126953,\
-	        0.02168821359337728266192257819966471288353204727173)
-
-#define YUV_TO_CIEXYZ\
-	MATRIX( 0.95047055865428309306963683411595411598682403564453,\
-	        0.22648030324549334180161963558930438011884689331055,\
-	        0.26274514929253273143316960158699657768011093139648,\
-	        0.99999999999999988897769753748434595763683319091797,\
-	       -0.13613114642319409930415474718756740912795066833496,\
-	       -0.17294595255115238763288232348713790997862815856934,\
-	        1.08882873639588373393394249433185905218124389648438,\
-	        1.89129144197893928058817891724174842238426208496094,\
-	       -0.04704173528403532422714761196402832865715026855469)
-
-#define YPBPR_TO_CIEXYZ\
-	MATRIX( 0.95047055865428298204733437160030007362365722656250,\
-	        0.14433968424876231217979238863335922360420227050781,\
-	        0.30616461986760712399302519770571961998939514160156,\
-	        0.99999999999999977795539507496869191527366638183594,\
-	       -0.00002022802471486617736928792510298080742359161377,\
-	        0.00008771894888734421691367515450110659003257751465,\
-	        1.08882873639588373393394249433185905218124389648438,\
-	        0.93827031735982591165168287261622026562690734863281,\
-	       -0.01609699914324668607035206946420657914131879806519)
-
-#define YCGCO_TO_CIEXYZ\
-	MATRIX( 0.95047055865428309306963683411595411598682403564453,\
-	       -0.23531882816325136453805555447615915909409523010254,\
-	        0.23202019775596791073546398820326430723071098327637,\
-	        0.99999999999999988897769753748434595763683319091797,\
-	        0.43030346098206362359661625305307097733020782470703,\
-	        0.14049847124784842211653312915586866438388824462891,\
-	        1.08882873639588373393394249433185905218124389648438,\
-	       -0.85044482623220662986796014592982828617095947265625,\
-	       -0.93096889579069830311652822274481877684593200683594)
-
 #define CIE1960UCS_TO_CIEXYZ(FROM_U, FROM_V, FROM_Y, TO_X, TO_Y, TO_Z)\
 	do {\
 		TYPE u__ = (FROM_U), v__ = (FROM_V), Y__ = (FROM_Y);\
@@ -228,31 +139,6 @@
 		(TO_H) = h__;\
 	} while (0)
 
-#define SRGB_TO_YIQ\
-	MATRIX( 0.299, 0.587, 0.114,\
-	        0.59571613491277464191853141528554260730743408203125, /* (0.877 cos 33°)(1 - 0.299) - (0.492 sin 33°)(-0.299) */\
-	       -0.27445283783925644716106262421817518770694732666016, /* (0.877 cos 33°)(-0.587)    - (0.492 sin 33°)(-0.587) */\
-	       -0.32126329707351808373516632855171337723731994628906, /* (0.877 cos 33°)(-0.114)    - (0.492 sin 33°)(1 - 0.114) */\
-	        0.21145640212011795888713550084503367543220520019531, /* (0.877 sin 33°)(1 - 0.299) + (0.492 cos 33°)(-0.299) */\
-	       -0.52259104529161115593183239980135113000869750976562, /* (0.877 sin 33°)(-0.587)    + (0.492 cos 33°)(-0.587) */\
-	        0.31113464317149330806699936147197149693965911865234) /* (0.877 sin 33°)(-0.114)    + (0.492 cos 33°)(1 - 0.114) */
-
-#define CIEXYZ_TO_YIQ\
-	MATRIX( 0.40627729168038273499519164033699780702590942382812,\
-	        0.61835674212166968910509012857801280915737152099609,\
-	       -0.00414330221353725880462093300593551248311996459961,\
-	        2.17852787350219845308174626552499830722808837890625,\
-	       -1.36502666214454104753883711964590474963188171386719,\
-	       -0.64803574634025240541745915834326297044754028320312,\
-	        1.20905577682138853923277110880007967352867126464844,\
-	       -1.36890364998339797431015085749095305800437927246094,\
-	        0.20180559439597040016778350945969577878713607788086)
-
-#define SRGB_TO_YDBDR\
-	MATRIX( 0.299,  0.587, 0.114,\
-	       -0.450, -0.883, 1.333,\
-	       -1.333,  1.116, 0.217)
-
 #define YUV_TO_YDBDR(FROM_Y, FROM_U, FROM_V, TO_Y, TO_DB, TO_DR)\
 	do {\
 		TYPE U__ = (FROM_U), V__ = (FROM_V);\
@@ -261,17 +147,6 @@
 		(TO_DR) = V__ * D(-2.169);\
 	} while (0)
 
-#define CIEXYZ_TO_YDBDR\
-	MATRIX( 0.40627729168038273499519164033699780702590942382812,\
-	        0.61835674212166968910509012857801280915737152099609,\
-	       -0.00414330221353725880462093300593551248311996459961,\
-	       -0.52816561102614745237815441214479506015777587890625,\
-	       -1.23677481526212962315014465275453403592109680175781,\
-	        1.59692761635924940222253098909277468919754028320312,\
-	       -5.38914174974103143966885909321717917919158935546875,\
-	        4.09835630362728497999569299281574785709381103515625,\
-	        0.94033545560642795013706063400604762136936187744141)
-
 #define YDBDR_TO_YUV(FROM_Y, FROM_DB, FROM_DR, TO_Y, TO_U, TO_V)\
 	do {\
 		TYPE DB__ = (FROM_DB), DR__ = (FROM_DR);\
@@ -280,28 +155,6 @@
 		(TO_V) = DR__ / D(-2.169);\
 	} while (0)
 
-#define SRGB_TO_YUV\
-	MATRIX( 0.29899999999999998800959133404830936342477798461914,\
-	        0.58699999999999996624922005139524117112159729003906,\
-	        0.11400000000000000410782519111307919956743717193604,\
-	       -0.14662756598240470062854967636667424812912940979004,\
-	       -0.28771586836102963635752871596196200698614120483398,\
-	        0.43434343434343436474165400795754976570606231689453,\
-	        0.61456892577224520035628074765554629266262054443359,\
-	       -0.51452282157676354490405401520547457039356231689453,\
-	       -0.10004610419548178035231700278018251992762088775635)
-
-#define CIEXYZ_TO_YUV\
-	MATRIX( 0.40627729168038273499519164033699780702590942382812,\
-	        0.61835674212166968910509012857801280915737152099609,\
-	       -0.00414330221353725880462093300593551248311996459961,\
-	       -0.17209697328971895746718701047939248383045196533203,\
-	       -0.40298951295605395239718404809536878019571304321289,\
-	        0.52034135430408912093014350830344483256340026855469,\
-	        2.48462044709130047692724474472925066947937011718750,\
-	       -1.88951420176453876997868519538315013051033020019531,\
-	       -0.43353409663735725798616726933687459677457809448242)
-
 #define SRGB_TO_YPBPR(FROM_R, FROM_G, FROM_B, TO_Y, TO_PB, TO_PR)\
 	do {\
 		TYPE R__ = (FROM_R), G__ = (FROM_G), B__ = (FROM_B);\
@@ -313,33 +166,6 @@
 		(TO_PR) = R__ - Y__;\
 	 } while (0)
 
-#define CIEXYZ_TO_YPBPR\
-	MATRIX(-0.00028314209073960778378920011277841695118695497513,\
-	        1.00019821310075673892470149439759552478790283203125,\
-	        0.00006512054470741990286342115723527967929840087891,\
-	        0.05592664565509243568275365987574332393705844879150,\
-	       -1.20422439283671711685030913940863683819770812988281,\
-	        1.05716144717799576113748116767965257167816162109375,\
-	        3.24072939673847715269516811531502753496170043945312,\
-	       -2.53733297492083753610359053709544241428375244140625,\
-	       -0.49859531356743613805804216099204495549201965332031)
-
-#define SRGB_TO_YCGCO\
-	MATRIX( 0.25, 0.50,  0.25,\
-	       -0.25, 0.50, -0.25,\
-	        0.50, 0.,   -0.50)
-
-#define CIEXYZ_TO_YCGCO\
-	MATRIX( 0.33938913643068269188063368346774950623512268066406,\
-	        0.50271574450517486631895280879689380526542663574219,\
-	        0.16045211478220866574417868832824751734733581542969,\
-	       -1.30865574267536244335019546269904822111129760742188,\
-	        1.37329621528319534284889869013568386435508728027344,\
-	       -0.11889607256777862120955546743061859160661697387695,\
-	        1.59240137554169236544510113162687048316001892089844,\
-	       -0.66655429104206020962664069884340278804302215576172,\
-	       -0.77787838037271606062006412685150280594825744628906)
-
 #define CIEUVW_TO_CIE1960UCS(FROM_U, FROM_V, FROM_W, TO_U, TO_V, TO_Y, FROM_U0, FROM_V0)\
 	do {\
 		TYPE U__ = (FROM_U), V__ = (FROM_V), W__ = (FROM_W), Y__;\
@@ -380,3 +206,5 @@
 		(TO_V) = w__ * (V__ - v0__);\
 		(TO_W) = Y__;\
 	} while (0)
+
+#include "conversion-matrices.h"
diff --git a/double.c b/double.c
index 30aa502..3ef983f 100644
--- a/double.c
+++ b/double.c
@@ -24,6 +24,7 @@
 #define libcolour_ycgco_t      libcolour_ycgco_lf_t
 #define libcolour_cie1960ucs_t libcolour_cie1960ucs_lf_t
 #define libcolour_cieuvw_t     libcolour_cieuvw_lf_t
+#define libcolour_yes_t        libcolour_yes_lf_t
 
 #define TYPE double
 #define LIST_MODELS(X) LIBCOLOUR_LIST_MODELS(X, lf)
diff --git a/en_masse-template.c b/en_masse-template.c
index b539328..e131188 100644
--- a/en_masse-template.c
+++ b/en_masse-template.c
@@ -55,6 +55,27 @@
 		}\
 	} while (0)
 
+#define DEFAULT_CONVERSION(FROM, TO)\
+	case LIBCOLOUR_##FROM:\
+		conversion_by_matrix(XARGUMENTS, FROM##_TO_##TO);\
+		break
+
+#define DEFAULT_CONVERSION_FROM_SRGB(TO)\
+	case LIBCOLOUR_SRGB:\
+		LINEAR_SRGB;\
+		conversion_by_matrix(XARGUMENTS, SRGB_TO_##TO);\
+		break
+
+#define DEFAULT_CONV_0(FROM, TO)\
+	case LIBCOLOUR_##FROM:\
+		CONV_0(FROM##_TO_##TO);\
+		break
+
+#define DEFAULT_CONV_N(FROM, TO, ...)\
+	case LIBCOLOUR_##FROM:\
+		CONV_N(FROM##_TO_##TO, __VA_ARGS__);\
+		break
+
 
 
 #define X(C, T, N) static void to_##N(const libcolour_colour_t *from, const T *to, XPARAMETERS);
@@ -221,12 +242,16 @@ to_srgb(PARAMETERS(colour, srgb))
 {
 	libcolour_srgb_t tmp;
 	switch (from->model) {
+	DEFAULT_CONVERSION(YCGCO, SRGB);
+	DEFAULT_CONVERSION(YDBDR, SRGB);
+	DEFAULT_CONVERSION(YES, SRGB);
+	DEFAULT_CONVERSION(YIQ, SRGB);
+	DEFAULT_CONVERSION(YUV, SRGB);
+	DEFAULT_CONV_0(YPBPR, SRGB);
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_SRGB);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, SRGB);
 	case LIBCOLOUR_SRGB:
 	srgb_to_srgb:
 		if (from->srgb.with_transfer != to->with_transfer) {
@@ -241,21 +266,6 @@ to_srgb(PARAMETERS(colour, srgb))
 			}
 		}
 		return;
-	case LIBCOLOUR_YIQ:
-		conversion_by_matrix(XARGUMENTS, YIQ_TO_SRGB);
-		break;
-	case LIBCOLOUR_YDBDR:
-		conversion_by_matrix(XARGUMENTS, YDBDR_TO_SRGB);
-		break;
-	case LIBCOLOUR_YPBPR:
-		CONV_0(YPBPR_TO_SRGB);
-		break;
-	case LIBCOLOUR_YUV:
-		conversion_by_matrix(XARGUMENTS, YUV_TO_SRGB);
-		break;
-	case LIBCOLOUR_YCGCO:
-		conversion_by_matrix(XARGUMENTS, YCGCO_TO_SRGB);
-		break;
 	}
 	if (to->with_transfer) {
 		tmp = *to;
@@ -317,6 +327,12 @@ to_ciexyz(PARAMETERS(colour, ciexyz))
 {
 	libcolour_colour_t tmp;
 	switch (from->model) {
+	DEFAULT_CONVERSION(YCGCO, CIEXYZ);
+	DEFAULT_CONVERSION(YDBDR, CIEXYZ);
+	DEFAULT_CONVERSION(YES, CIEXYZ);
+	DEFAULT_CONVERSION(YIQ, CIEXYZ);
+	DEFAULT_CONVERSION(YPBPR, CIEXYZ);
+	DEFAULT_CONVERSION(YUV, CIEXYZ);
 	case LIBCOLOUR_RGB:
 		if (from->rgb.with_transfer) {
 			tmp.rgb = from->rgb;
@@ -331,10 +347,7 @@ to_ciexyz(PARAMETERS(colour, ciexyz))
 		to_srgb(ARGUMENTS(from, &tmp.srgb));
 		from = (const void *)&tmp.srgb;
 		/* fall through */
-	case LIBCOLOUR_SRGB:
-		LINEAR_SRGB;
-		conversion_by_matrix(XARGUMENTS, SRGB_TO_CIEXYZ);
-		break;
+	DEFAULT_CONVERSION_FROM_SRGB(CIEXYZ);
 	case LIBCOLOUR_CIEXYY:
 		CONV_0(CIEXYY_TO_CIEXYZ);
 		break;
@@ -352,21 +365,6 @@ to_ciexyz(PARAMETERS(colour, ciexyz))
 	case LIBCOLOUR_CIELUV:
 		CONV_N(CIELUV_TO_CIEXYZ, from->cieluv.white.X, from->cieluv.white.Y, from->cieluv.white.Z);
 		break;
-	case LIBCOLOUR_YIQ:
-		conversion_by_matrix(XARGUMENTS, YIQ_TO_CIEXYZ);
-		break;
-	case LIBCOLOUR_YDBDR:
-		conversion_by_matrix(XARGUMENTS, YDBDR_TO_CIEXYZ);
-		break;
-	case LIBCOLOUR_YUV:
-		conversion_by_matrix(XARGUMENTS, YUV_TO_CIEXYZ);
-		break;
-	case LIBCOLOUR_YPBPR:
-		conversion_by_matrix(XARGUMENTS, YPBPR_TO_CIEXYZ);
-		break;
-	case LIBCOLOUR_YCGCO:
-		conversion_by_matrix(XARGUMENTS, YCGCO_TO_CIEXYZ);
-		break;
 	case LIBCOLOUR_CIEUVW:
 		tmp.cie1960ucs.model = LIBCOLOUR_CIE1960UCS;
 		to_cie1960ucs(ARGUMENTS(from, &tmp.cie1960ucs));
@@ -477,18 +475,18 @@ static void
 to_yiq(PARAMETERS(colour, yiq))
 {
 	switch (from->model) {
+	DEFAULT_CONVERSION_FROM_SRGB(YIQ);
+	DEFAULT_CONVERSION(YCGCO, YIQ);
+	DEFAULT_CONVERSION(YDBDR, YIQ);
+	DEFAULT_CONVERSION(YES, YIQ);
+	DEFAULT_CONVERSION(YPBPR, YIQ);
+	DEFAULT_CONVERSION(YUV, YIQ);
 	case LIBCOLOUR_YIQ:
 		break;
-	case LIBCOLOUR_SRGB:
-		LINEAR_SRGB;
-		conversion_by_matrix(XARGUMENTS, SRGB_TO_YIQ);
-		break;
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_YIQ);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, YIQ);
 	}
 }
 
@@ -497,21 +495,20 @@ static void
 to_ydbdr(PARAMETERS(colour, ydbdr))
 {
 	switch (from->model) {
+	DEFAULT_CONVERSION_FROM_SRGB(YDBDR);
+	DEFAULT_CONVERSION(YCGCO, YDBDR);
+	DEFAULT_CONVERSION(YES, YDBDR);
+	DEFAULT_CONVERSION(YIQ, YDBDR);
+	DEFAULT_CONVERSION(YPBPR, YDBDR);
 	case LIBCOLOUR_YDBDR:
 		break;
-	case LIBCOLOUR_SRGB:
-		LINEAR_SRGB;
-		conversion_by_matrix(XARGUMENTS, SRGB_TO_YDBDR);
-		break;
 	case LIBCOLOUR_YUV:
 		CONV_0(YUV_TO_YDBDR);
 		break;
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_YDBDR);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, YDBDR);
 	}
 }
 
@@ -520,21 +517,20 @@ static void
 to_yuv(PARAMETERS(colour, yuv))
 {
 	switch (from->model) {
+	DEFAULT_CONVERSION_FROM_SRGB(YUV);
+	DEFAULT_CONVERSION(YCGCO, YUV);
+	DEFAULT_CONVERSION(YES, YUV);
+	DEFAULT_CONVERSION(YIQ, YUV);
+	DEFAULT_CONVERSION(YPBPR, YUV);
 	case LIBCOLOUR_YUV:
 		break;
 	case LIBCOLOUR_YDBDR:
 		CONV_0(YDBDR_TO_YUV);
 		break;
-	case LIBCOLOUR_SRGB:
-		LINEAR_SRGB;
-		conversion_by_matrix(XARGUMENTS, SRGB_TO_YUV);
-		break;
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_YUV);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, YUV);
 	}
 }
 
@@ -543,6 +539,11 @@ static void
 to_ypbpr(PARAMETERS(colour, ypbpr))
 {
 	switch (from->model) {
+	DEFAULT_CONVERSION(YCGCO, YPBPR);
+	DEFAULT_CONVERSION(YDBDR, YPBPR);
+	DEFAULT_CONVERSION(YES, YPBPR);
+	DEFAULT_CONVERSION(YIQ, YPBPR);
+	DEFAULT_CONVERSION(YUV, YPBPR);
 	case LIBCOLOUR_YPBPR:
 		break;
 	case LIBCOLOUR_SRGB:
@@ -552,9 +553,7 @@ to_ypbpr(PARAMETERS(colour, ypbpr))
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_YPBPR);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, YPBPR);
 	}
 }
 
@@ -563,18 +562,18 @@ static void
 to_ycgco(PARAMETERS(colour, ycgco))
 {
 	switch (from->model) {
+	DEFAULT_CONVERSION_FROM_SRGB(YCGCO);
+	DEFAULT_CONVERSION(YDBDR, YCGCO);
+	DEFAULT_CONVERSION(YES, YCGCO);
+	DEFAULT_CONVERSION(YIQ, YCGCO);
+	DEFAULT_CONVERSION(YPBPR, YCGCO);
+	DEFAULT_CONVERSION(YUV, YCGCO);
 	case LIBCOLOUR_YCGCO:
 		break;
-	case LIBCOLOUR_SRGB:
-		LINEAR_SRGB;
-		conversion_by_matrix(XARGUMENTS, SRGB_TO_YCGCO);
-		break;
 	default:
 		to_ciexyz(ARGUMENTS(from, NULL));
 		/* fall through */
-	case LIBCOLOUR_CIEXYZ:
-		conversion_by_matrix(XARGUMENTS, CIEXYZ_TO_YCGCO);
-		break;
+	DEFAULT_CONVERSION(CIEXYZ, YCGCO);
 	}
 }
 
@@ -614,6 +613,25 @@ to_cieuvw(PARAMETERS(colour, cieuvw))
 	}
 }
 
+static void
+to_yes(PARAMETERS(colour, yes))
+{
+	switch (from->model) {
+	DEFAULT_CONVERSION_FROM_SRGB(YES);
+	DEFAULT_CONVERSION(YCGCO, YES);
+	DEFAULT_CONVERSION(YDBDR, YES);
+	DEFAULT_CONVERSION(YIQ, YES);
+	DEFAULT_CONVERSION(YPBPR, YES);
+	DEFAULT_CONVERSION(YUV, YES);
+	case LIBCOLOUR_YES:
+		break;
+	default:
+		to_ciexyz(ARGUMENTS(from, NULL));
+		/* fall through */
+	DEFAULT_CONVERSION(CIEXYZ, YES);
+	}
+}
+
 
 int
 libcolour_convert_en_masse(const libcolour_colour_t *from, const libcolour_colour_t *to,
diff --git a/float.c b/float.c
index c1e28a5..f7775a1 100644
--- a/float.c
+++ b/float.c
@@ -24,6 +24,7 @@
 #define libcolour_ycgco_t      libcolour_ycgco_f_t
 #define libcolour_cie1960ucs_t libcolour_cie1960ucs_f_t
 #define libcolour_cieuvw_t     libcolour_cieuvw_f_t
+#define libcolour_yes_t        libcolour_yes_f_t
 
 #define TYPE float
 #define LIST_MODELS(X) LIBCOLOUR_LIST_MODELS(X, f)
diff --git a/libcolour.h b/libcolour.h
index 51dfaa8..8d7ae4f 100644
--- a/libcolour.h
+++ b/libcolour.h
@@ -162,7 +162,8 @@
 	_(LIBCOLOUR_YPBPR,      libcolour_ypbpr_##RES##_t,      ypbpr,      __VA_ARGS__)\
 	_(LIBCOLOUR_YCGCO,      libcolour_ycgco_##RES##_t,      ycgco,      __VA_ARGS__)\
 	_(LIBCOLOUR_CIE1960UCS, libcolour_cie1960ucs_##RES##_t, cie1960ucs, __VA_ARGS__)\
-	_(LIBCOLOUR_CIEUVW,     libcolour_cieuvw_##RES##_t,     cieuvw,     __VA_ARGS__)
+	_(LIBCOLOUR_CIEUVW,     libcolour_cieuvw_##RES##_t,     cieuvw,     __VA_ARGS__)\
+	_(LIBCOLOUR_YES,        libcolour_yes_##RES##_t,        yes,        __VA_ARGS__)
 
 #define LIBCOLOUR_LIST_MODELS(_, RES)\
 	_(LIBCOLOUR_RGB,        libcolour_rgb_##RES##_t,        rgb)\
@@ -178,7 +179,8 @@
 	_(LIBCOLOUR_YPBPR,      libcolour_ypbpr_##RES##_t,      ypbpr)\
 	_(LIBCOLOUR_YCGCO,      libcolour_ycgco_##RES##_t,      ycgco)\
 	_(LIBCOLOUR_CIE1960UCS, libcolour_cie1960ucs_##RES##_t, cie1960ucs)\
-	_(LIBCOLOUR_CIEUVW,     libcolour_cieuvw_##RES##_t,     cieuvw)
+	_(LIBCOLOUR_CIEUVW,     libcolour_cieuvw_##RES##_t,     cieuvw)\
+	_(LIBCOLOUR_YES,        libcolour_yes_##RES##_t,        yes)
 
 
 #define LIBCOLOUR_RGB LIBCOLOUR_RGB
@@ -195,6 +197,7 @@
 #define LIBCOLOUR_YCGCO LIBCOLOUR_YCGCO
 #define LIBCOLOUR_CIE1960UCS LIBCOLOUR_CIE1960UCS
 #define LIBCOLOUR_CIEUVW LIBCOLOUR_CIEUVW
+#define LIBCOLOUR_YES LIBCOLOUR_YES
 
 
 typedef enum libcolour_model {
@@ -405,6 +408,13 @@ typedef struct libcolour_cielchuv_##RES {\
 	TYPE one_revolution;\
 } libcolour_cielchuv_##RES##_t;\
 \
+typedef struct libcolour_yes_##RES {\
+	enum libcolour_model model;\
+	TYPE Y;\
+	TYPE E;\
+	TYPE S;\
+} libcolour_yes_##RES##_t;\
+\
 typedef struct libcolour_rgb_##RES {\
 	enum libcolour_model model;\
 	TYPE R;\
diff --git a/long-double.c b/long-double.c
index 350ef87..dc46897 100644
--- a/long-double.c
+++ b/long-double.c
@@ -24,6 +24,7 @@
 #define libcolour_ycgco_t      libcolour_ycgco_llf_t
 #define libcolour_cie1960ucs_t libcolour_cie1960ucs_llf_t
 #define libcolour_cieuvw_t     libcolour_cieuvw_llf_t
+#define libcolour_yes_t        libcolour_yes_llf_t
 
 #define TYPE long double
 #define LIST_MODELS(X) LIBCOLOUR_LIST_MODELS(X, llf)
diff --git a/matrices.py b/matrices.py
new file mode 100755
index 0000000..485374c
--- /dev/null
+++ b/matrices.py
@@ -0,0 +1,184 @@
+#!/usr/bin/env python
+# Both Python 2 and Python 3 will work
+
+import sys, math
+
+FORMAT = '%.50f'
+DELIMITER = ', '
+
+def _divrow(R, d):
+    return [c / d for c in R]
+    
+def _subrow(A, B, m):
+    return [a - b * m for a, b in zip(A, B)]
+    
+def transpose(M):
+    r, c = len(M), len(M[0])
+    return [[M[y][x] for y in range(r)] for x in range(c)]
+
+def to_vector(M):
+    if len(M[0]) == 1:
+        return tuple(R[0] for R in M)
+    elif len(M) == 1:
+        return M[0]
+    raise Exception('Invalid arguments')
+
+def _multiply(A, B):
+    if isinstance(A[0], int) or isinstance(A[0], float):
+        A = [A]
+    if isinstance(B[0], int) or isinstance(B[0], float):
+        B = [B]
+    ar, ac, br, bc = len(A), len(A[0]), len(B), len(B[0])
+    if ac != br:
+        if ac == bc:
+            B, br, bc = transpose(B), bc, br
+        elif ar == br:
+            A, ar, ac = transpose(A), ac, ar
+        else:
+            raise Exception('Invalid arguments')
+    return [[sum(A[r][i] * B[i][c] for i in range(ac)) for c in range(bc)] for r in range(ar)]
+    
+def multiply(*Ms):
+    R, Ms = Ms[-1], list(Ms)[-2::-1]
+    for M in Ms:
+        R = _multiply(M, R)
+    return R
+
+def invert(M):
+    r, c = len(M), len(M[0])
+    if r != c:
+        raise Exception('Invalid arguments')
+    I = [[1 if x == y else 0 for x in range(c)] for y in range(r)]
+    M = [MR + IR for MR, IR in zip(M, I)]
+    for r1 in range(r):
+        if M[r1][r1] == 0:
+            for r2 in range(r1 + 1, r):
+                if M[r2][r1] != 0:
+                    break
+            if r2 == r:
+                raise Exception('Not invertable')
+            M[r1], M[r2] = M[r2], M[r1]
+        M[r1] = _divrow(M[r1], M[r1][r1])
+        for r2 in range(r1 + 1, r):
+            M[r2] = _subrow(M[r2], M[r1], M[r2][r1])
+    for r1 in reversed(range(r)):
+        for r2 in reversed(range(r1)):
+            M[r2] = _subrow(M[r2], M[r1], M[r2][r1])
+    return [R[c:] for R in M]
+
+def str_matrix(M):
+    rfmt = '%s%s%s%s%s' % (FORMAT, DELIMITER, FORMAT, DELIMITER, FORMAT)
+    fmt = '%s\n%s\n%s' % (rfmt, rfmt, rfmt)
+    return fmt % tuple(M[0] + M[1] +M[2])
+
+def print_matrix(M):
+    print(str_matrix(M))
+
+def matrix(m11, m12, m13, m21, m22, m23, m31, m32, m33):
+    return [[m11, m12, m13], [m21, m22, m23], [m31, m32, m33]]
+
+def _cos(deg):
+    return math.cos(deg * math.pi / 180.)
+
+def _sin(deg):
+    return math.sin(deg * math.pi / 180.)
+
+def _yiq_i(k, a, b):
+    return 0.877 * _cos(33.) * (a - k) - (0.492 * _sin(33.)) * (b - k)
+
+def _yiq_q(k, a, b):
+    return 0.877 * _sin(33.) * (a - k) + (0.492 * _cos(33.)) * (b - k)
+
+
+matrices = {
+    ('srgb', 'yes') : matrix(0.253,  0.684,  0.063,
+                             0.50,  -0.50,   0.,
+                             0.25,   0.25,  -0.50),
+
+    ('ycgco', 'srgb') : matrix(1., -1.,  1.,
+                               1.,  1.,  0.,
+                               1., -1., -1.),
+
+    ('srgb', 'yiq') : matrix(0.299, 0.587, 0.114,
+                             _yiq_i(0.299, 1, 0), _yiq_i(0.587, 0, 0), _yiq_i(0.114, 0, 1),
+                             _yiq_q(0.299, 1, 0), _yiq_q(0.587, 0, 0), _yiq_q(0.114, 0, 1)),
+
+    ('srgb', 'ydbdr') : matrix( 0.299,  0.587, 0.114,
+                               -0.450, -0.883, 1.333,
+                               -1.333,  1.116, 0.217),
+
+    ('srgb', 'ypbpr') : matrix(    0.2126,  0.7152,     0.0722,
+                                  -0.2126, -0.7152, 1 - 0.0722,
+                               1 - 0.2126, -0.7152,    -0.0722),
+
+    ('srgb', 'ciexyz') : matrix(0.412457445582367576708548995157,
+                                0.357575865245515878143578447634,
+                                0.180437247826399665973085006954,
+                                0.212673370378408277403536885686,
+                                0.715151730491031756287156895269,
+                                0.072174899130559869164791564344,
+                                0.019333942761673460208893260415,
+                                0.119191955081838593666354597644,
+                                0.950302838552371742508739771438),
+
+    ('yuv', 'ydbdr') : matrix(1., 0.,     0.,
+                              0., 3.069,  0.,
+                              0., 0.,    -2.169),
+}
+
+if __name__ == '__main__':
+    models = set()
+    for (f, t) in list(matrices.keys()):
+        models.add(f)
+        models.add(t)
+        if (t, f) not in matrices:
+            matrices[(t, f)] = invert(matrices[(f, t)])
+
+    while True:
+        ms = list(matrices.keys())
+        added = 0
+        for m1 in models:
+            for m2 in models:
+                if m1 == m2:
+                    continue
+                for m3 in models:
+                    if m1 == m3 or m2 == m3:
+                        continue
+                    if (m1, m3) in ms:
+                        continue
+                    if (m1, m2) not in ms:
+                        continue
+                    if (m2, m3) not in ms:
+                        continue
+                    added += 1
+                    m = multiply(matrices[(m2, m3)], matrices[(m1, m2)])
+                    matrices[(m1, m3)] = m
+        if not added:
+            break
+
+    for (f, t) in sorted(matrices.keys()):
+        M = multiply(matrices[(t, f)], matrices[(f, t)])
+        for r in range(len(M)):
+            for c in range(len(M[r])):
+                x = M[r][c]
+                x -= 1 if r == c else 0
+                x *= x
+                if x > 0.0001:
+                    sys.stderr.write('(%s, %s)(%s, %s) != I\n' % (t, f, f, t))
+                    for r in M:
+                        for c in r:
+                            sys.stderr.write('\t%lg' % c)
+                        sys.stderr.write('\n')
+                    sys.exit(1)
+
+    for (f, t) in sorted(matrices.keys()):
+        M = matrices[(f, t)]
+        macro = '%s_TO_%s' % (f.upper(), t.upper())
+        print('')
+        print('#ifndef %s' % macro)
+        print('# define %s MATRIX(\\' % macro)
+        for row in M:
+            a = ', '.join([FORMAT] * len(row))
+            b = ')' if row is M[-1] else ',\\'
+            print(('\t' + a + b) % tuple(row))
+        print('#endif')
diff --git a/test.c b/test.c
index 2829f12..693e7d4 100644
--- a/test.c
+++ b/test.c
@@ -724,6 +724,7 @@ main(int argc, char *argv[])
 	 *     YCgCo
 	 *     CIE 1960 UCS
 	 *     CIEUVW
+	 *     YES
 	 */
 	c1.srgb.with_transfer = 0;
 	c1.srgb.R = 32 / 255., c1.srgb.G = 65 / 255., c1.srgb.B = 32 / 255.;