GL 3.0, UYVY422 shader using GL_RGB_422_APPLE as internalFormat, GL_UNSIGNED_SHORT_8_8_APPLE as format

uyvy422.c

static const char* YUYV_VS = ""
  "#version 150\n"
  "uniform mat4 u_pm;"
  "uniform mat4 u_mm;"
  "in vec4 a_pos;"
  "in vec2 a_tex;"
  "out vec2 v_tex;"

  "void main() {"
  " gl_Position = u_pm * u_mm * a_pos; "
    " v_tex = a_tex;"
  "}"
  "";

static const char* YUYV_FS = ""
  "#version 150\n"
  "uniform sampler2D u_tex;"
  "out vec4 outcol;"
  "in vec2 v_tex;"

  "const vec3 R_cf = vec3(1.164383,  0.000000,  1.596027);"
  "const vec3 G_cf = vec3(1.164383, -0.391762, -0.812968);"
  "const vec3 B_cf = vec3(1.164383,  2.017232,  0.000000);"
  "const vec3 offset = vec3(-0.0625, -0.5, -0.5);"

  "void main() {"
  "  vec3 tc =  texture( u_tex, v_tex ).rgb;"
  "  vec3 yuv = vec3(tc.g, tc.b, tc.r);"
  "  yuv += offset;"
  "  outcol.r = dot(yuv, R_cf);"
  "  outcol.g = dot(yuv, G_cf);"
  "  outcol.b = dot(yuv, B_cf);"
  "  outcol.a = 1.0;"
  "}"
  "";

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