I found a way to convert bitmap images into an 8bit format, but 16bit images prove to be a challenge. The only way I was able to display a 16bit image so far is by converting one manually.

I found a couple tools to help me convert bitmaps: "lcd-image-converter" and "LCDAssistant". The lcd-image-converter, however, looks to be more capable, so I will try to figure it out.

Fig. 4 - lcd-image-converter main window