/*

     File: Shader.fsh

 Abstract: Fragment shader for converting Y/UV textures to RGB.

  Version: 1.0

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 */

uniform sampler2D SamplerY;

uniform sampler2D SamplerUV;

varying highp vec2 texCoordVarying;

void main()

{

    mediump vec3 yuv;

    lowp vec3 rgb;

    yuv.x = texture2D(SamplerY, texCoordVarying).r;

    yuv.yz = texture2D(SamplerUV, texCoordVarying).rg - vec2(0.5, 0.5);

    // BT.601, which is the standard for SDTV is provided as a reference

    /*

    rgb = mat3(    1,       1,     1,

                   0, -.34413, 1.772,

               1.402, -.71414,     0) * yuv;

     */

    // Using BT.709 which is the standard for HDTV

    rgb = mat3(      1,       1,      1,

                     0, -.18732, 1.8556,

               1.57481, -.46813,      0) * yuv;

    gl_FragColor = vec4(rgb, 1);

}