uniform sampler2D OGL2Texture;

const vec3 RGBtoY = vec3(0.299, 0.587, 0.114);
const vec3 RGBtoI = vec3(0.596,-0.275,-0.321);
const vec3 RGBtoQ = vec3(0.212,-0.523, 0.311);
const vec3 YIQtoR = vec3(1.0, 0.95568806036115671171, 0.61985809445637075388);
const vec3 YIQtoG = vec3(1.0,-0.27158179694405859326,-0.64687381613840131330);
const vec3 YIQtoB = vec3(1.0,-1.10817732668266195230, 1.70506455991918171490);

void main()
{
	vec3 c0, c1;

	c0 = (texture2D(OGL2Texture,gl_TexCoord[0].xy).rgb +
         (texture2D(OGL2Texture,gl_TexCoord[0].zy).rgb) * 0.25 +
         (texture2D(OGL2Texture,gl_TexCoord[0].xw).rgb) * 0.25 +
         texture2D(OGL2Texture,gl_TexCoord[1].xy).rgb +
         (texture2D(OGL2Texture,gl_TexCoord[1].zy).rgb) * 0.25 +
         (texture2D(OGL2Texture,gl_TexCoord[1].xw).rgb) * 0.25 +
         texture2D(OGL2Texture,gl_TexCoord[2].xy).rgb +
         (texture2D(OGL2Texture,gl_TexCoord[2].zy).rgb) * 0.25 +
         (texture2D(OGL2Texture,gl_TexCoord[2].xw).rgb) * 0.25 +
         texture2D(OGL2Texture,gl_TexCoord[3].xy).rgb +
         (texture2D(OGL2Texture,gl_TexCoord[3].zy).rgb) * 0.25 +
         (texture2D(OGL2Texture,gl_TexCoord[3].xw).rgb) * 0.25 ) / 6.0;

	c1 = vec3(pow(dot(c0, RGBtoY), 1.2), dot(c0, RGBtoI) * 1.2, dot(c0, RGBtoQ) * 1.2);

	gl_FragColor = vec4(dot(c1, YIQtoR), dot(c1, YIQtoG), dot(c1, YIQtoB), 0.0);
}