git.sesse.net Git - movit/blob - ycbcr_input.frag

   1 // Implicit uniforms:
   2 // uniform sampler2D PREFIX(tex_y);
   3 // uniform sampler2D PREFIX(tex_cbcr);  // If CB_CR_SAME_TEXTURE.
   4 // uniform sampler2D PREFIX(tex_cb);    // If not CB_CR_SAME_TEXTURE.
   5 // uniform sampler2D PREFIX(tex_cr);    // If not CB_CR_SAME_TEXTURE.
   6
   7 vec4 FUNCNAME(vec2 tc) {
   8         // OpenGL's origin is bottom-left, but most graphics software assumes
   9         // a top-left origin. Thus, for inputs that come from the user,
  10         // we flip the y coordinate.
  11         tc.y = 1.0 - tc.y;
  12
  13         vec3 ycbcr;
  14         ycbcr.x = tex2D(PREFIX(tex_y), tc).x;
  15 #if CB_CR_SAME_TEXTURE
  16 #if CB_CR_OFFSETS_EQUAL
  17         ycbcr.yz = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cb_offset)).xy;
  18 #else
  19         ycbcr.y = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cb_offset)).x;
  20         ycbcr.z = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cr_offset)).x;
  21 #endif
  22 #else
  23         ycbcr.y = tex2D(PREFIX(tex_cb), tc + PREFIX(cb_offset)).x;
  24         ycbcr.z = tex2D(PREFIX(tex_cr), tc + PREFIX(cr_offset)).x;
  25 #endif
  26
  27         ycbcr -= PREFIX(offset);
  28
  29         vec4 rgba;
  30         rgba.rgb = PREFIX(inv_ycbcr_matrix) * ycbcr;
  31         rgba.a = 1.0;
  32         return rgba;
  33 }