Function stbi__paeth

include/stb/stb_image.h:4657–4668

};

static int stbi__paeth(int a, int b, int c)
{
   // This formulation looks very different from the reference in the PNG spec, but is
   // actually equivalent and has favorable data dependencies and admits straightforward
   // generation of branch-free code, which helps performance significantly.
   int thresh = c*3 - (a + b);
   int lo = a < b ? a : b;
   int hi = a < b ? b : a;
   int t0 = (hi <= thresh) ? lo : c;
   int t1 = (thresh <= lo) ? hi : t0;
   return t1;
}

static const stbi_uc stbi__depth_scale_table[9] = { 0, 0xff, 0x55, 0, 0x11, 0,0,0, 0x01 };