 + 8 alpha), no background color:<br>
<img width="85" height="62" src="./images/png/gray8a.png" alt="[Test image]">
</p>

<p><b>(G3)</b> 32 bpp grayscale (16 gray + 16 alpha), includes background color:<br>
<img width="85" height="62" src="./images/png/gray16a_bk.png" alt="[Test image]">
</p>

<p><b>(G4)</b> 32 bpp grayscale (16 gray + 16 alpha), no background color:<br>
<img width="85" height="62" src="./images/png/gray16a.png" alt="[Test image]">


<h3>Grayscale binary transparency</h3>

<p>Expected resul