32 lines
764 B
GLSL
32 lines
764 B
GLSL
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#include "/var/signal.glsl"
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#define signal 0 // [0 1]
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vec3 ntsc(vec3 color) {
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// convert to YIQ
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float y = dot(color, vec3(0.299, 0.587, 0.114));
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float i = dot(color, vec3(0.596, -.274, -.322));
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float q = dot(color, vec3(0.211, -.523, 0.312));
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// faux ntsc signal
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float carrier = 6.283 * 3.570 * gl_FragCoord.x;
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float phase = sin(carrier) * i + cos(carrier) * q;
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float quad = cos(carrier) * i - sin(carrier) * q;
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// decode faux signal
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i = quad * cos(carrier);
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q = phase * sin(carrier);
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// convert back to RGB
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vec3 yiqColor = vec3(y, i, q);
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vec3 outColor = vec3(0);
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outColor.r = dot(yiqColor, vec3(1, 0.956, 0.619));
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outColor.g = dot(yiqColor, vec3(1, -.272, -.674));
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outColor.b = dot(yiqColor, vec3(1, -1.106, 1.703));
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return outColor;
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}
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