PVS-Studio warning V636 for CxImage

psd_argb_color psd_alab_to_color(....)
{
  psd_double var_z;
  ....
  var_z = ( var_z - 16 / 116 ) / 7.787;
}

According to the rules of integer division, 16 / 116 == 0. That's why the result will be incorrect.

This suspicious code was found in CxImage project by PVS-Studio static code analyzer.
Warning message is:
V636 The '16 / 116' expression was implicitly casted from 'int' type to 'double' type. Consider utilizing an explicit type cast to avoid the loss of a fractional part. An example: double A = (double)(X) / Y;. color.c 125

PVS-Studio is a static analyzer for detecting bugs in the source code of applications written in C, C++, C++11, C++/CX. Site: http://www.viva64.com/en/pvs-studio/