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 // uniform mat3 PREFIX(ycbcr_matrix);
   7 // uniform vec3 PREFIX(offset);
   8 // uniform vec2 PREFIX(cb_offset);
   9 // uniform vec2 PREFIX(cr_offset);
  10
  11 vec4 FUNCNAME(vec2 tc) {
  12         // OpenGL's origin is bottom-left, but most graphics software assumes
  13         // a top-left origin. Thus, for inputs that come from the user,
  14         // we flip the y coordinate.
  15         tc.y = 1.0 - tc.y;
  16
  17         vec3 ycbcr;
  18 #if Y_CB_CR_SAME_TEXTURE
  19         ycbcr = tex2D(PREFIX(tex_y), tc).xyz;
  20 #else
  21         ycbcr.x = tex2D(PREFIX(tex_y), tc).x;
  22   #if CB_CR_SAME_TEXTURE
  23     #if CB_CR_OFFSETS_EQUAL
  24         ycbcr.yz = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cb_offset)).xy;
  25     #else
  26         ycbcr.y = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cb_offset)).x;
  27         ycbcr.z = tex2D(PREFIX(tex_cbcr), tc + PREFIX(cr_offset)).x;
  28     #endif
  29   #else
  30         ycbcr.y = tex2D(PREFIX(tex_cb), tc + PREFIX(cb_offset)).x;
  31         ycbcr.z = tex2D(PREFIX(tex_cr), tc + PREFIX(cr_offset)).x;
  32   #endif
  33 #endif
  34
  35         ycbcr -= PREFIX(offset);
  36
  37         vec4 rgba;
  38         rgba.rgb = PREFIX(inv_ycbcr_matrix) * ycbcr;
  39         rgba.a = 1.0;
  40         return rgba;
  41 }