3.7.1. LIMITATION OF POLARITY COORDINATE COLOR

Lecture

Consider a color image signal sensor, whose output coordinates are 3.7.1. LIMITATION OF POLARITY COORDINATE COLOR in the primary color system television receiver NTSC. This receiver can reproduce any color that has non-negative coordinates. These colors lie inside the cube of the color gamut shown in fig. 3.7.1, a. The tops of the cube correspond to the main colors of the NTSC receiver — red, green, blue, cyan, magenta, yellow, black, and white.

3.7.1. LIMITATION OF POLARITY COORDINATE COLOR

Fig. 3.7.1. The color gamut of the receiver NTSC: a - coordinate system 3.7.1. LIMITATION OF POLARITY COORDINATE COLOR ; b - coordinate system ; in - coordinate system ; g - the system of coordinates Karuyena-Loeva.

By means of a linear transformation we move to another color coordinate system 3.7.1. LIMITATION OF POLARITY COORDINATE COLOR :

3.7.1. LIMITATION OF POLARITY COORDINATE COLOR (3.7.1)

In tab. 3.7.1 shows the color coordinates and chromaticity coordinates of the main colors of the NTSC receiver for several coordinate systems. The color gamut provided by the phosphors of the NTSC receiver is shown in fig. 3.7.1 in various coordinate systems. Note that in the Karunen-Loeve coordinate system (Fig. 3.7.1, d), the color gamut is represented by a cube rotated relative to the coordinate axes.

Table 3.7.1. The color coordinates and chromaticity coordinates of the main colors of the NTSC receiver for several coordinate systems

	Red	Green	Blue	Blue	Purple	Yellow	White	The black
	1,000	0,000	0,000	0,000	1,000	1,000	1,000	0,000
	0,000	1,000	0,000	1,000	0,000	1,000	1,000	0,000
	0,000	0,000	1,000	1,000	1,000	0,000	1,000	0,000
	1,000	0,000	0,000	0,000	0,500	0,500	0.333	0.333
	0,000	1,000	0,000	0,500	0,000	0,500	0.333	0.333
	0,000	0,000	1,000	0,500	0,500	0,000	0.333	0.333,
X	0,607	0.174	0.20	0.375	0,808	0.781	0.982	0,000
Y	0,299	0.587	0.114	0.701	0.413	0.886	1,000	0,000
Z	0,000	0.066	1,117	1.183	1,117	0.066	1.183	0,000
x	0.670	0,210	0.140	0.166	0.346	0,451	0.310	0.310
y	0.330	0.710	0.080	0310	0.177	0311	0.316	0.316
z	-0,000	0.080	0.780	0.524	0.477	0.038	0374	0.374
	0.207	-0.026	-0.026	-0.052	0.180	0.181	0.154	0,000
	0.020	0.133	0.028	0.161	0.048	0.153	0.181	0,000
	0,000	0,010	0,200	0,210	0.199	0,010	0,210	0,000
	0.912	-0,219	-0,132	-0,164	0.421	0325	0.283	0.283
	0.089	1,130	0.139	0.506	0.113	0.446	0.333	0.333
	0,000	0.089	0.993	0.658	0.466	0.029	0384	0.384
U	0.405	0.116	0.134	0,250	0.539	0321	0.655	0,000
V	0,299	0.587	0.114	0.701	0.413	0.886	1,000	0,000
W	0.145	0.827	0.629	1,456	0.774	0.972	1.601	0,000
u	0.477	0.076	0.153	0.104	0.312	0.219	0.20	0.20
v	0.352	0.384	0.130	0,291	0.239	0.373	0.307	0.307
w	0.171	0.540	0.717	0.605	0.449	0.408	0.492	0.492
Y	0,299	0.587	0.114	0.701	0.413	0.886	1,000	0,000
I	0.596	-0,273	-0322	-0,595	0.272	0.322	0,000	0.000
Q	0,212	-0,522	0.315	-0,207	0.526	-0312	0,000	0,000
U *	217,358-	-130,319	-24,558	-108,566	100,385	22,144	0,000	0,000
V *	35,461	79,703	-90.508	-17.913	-61,336	80,125	0,000	0,000
W *	60,394	80,160	39,265	86,081	69,415	94,451	99,040	-17,000
S	220,232	152,760	93,781	110,034	117,640	83,128	0,000	0,000
	0.162	2,609	4,445	3,304	5.733	1,280	0,000	0,000
W *	60,594	80,160	39,265	86,081	69,415	94,451	99,040	-17,000
L	61,594	81,160	40,265	87,081	70,415	95,451	100,040	-16,000
	91,377-	137,815	52,227	-81,411	96,177	-16,977	0,000	0,000
	133,738	91,038	-99,233	-22,335	-47,269	115,670	0,000	0,000

This color can be described by chromaticity values.

3.7.1. LIMITATION OF POLARITY COORDINATE COLOR (3.7.2a)

3.7.1. LIMITATION OF POLARITY COORDINATE COLOR (3.7.2b)

and brightness

3.7.1. LIMITATION OF POLARITY COORDINATE COLOR (3.7.2в)

where are the color coordinates 3.7.1. LIMITATION OF POLARITY COORDINATE COLOR given by the relation (3.7.1), and the constant defined in Appendix 2. The transformation (3.7.2) of color coordinates into chromaticity coordinates is non-linear. In fig. 3.7.2 shows the color gamut of the receiver NTSC in coordinates .