For whoever is using a SSD1351 OLED display (128x128 or 128x96, 16bits color), I just made available a library to load a Windows Bitmap (currently 16bits 565-color encoded only, more later on) on that display. It’s strongly derived from an Adafruit demo to load a 24bits bitmap.
Name of the library is Bitmap. It’s currently display dependent (because it’s switching the display Off/on while loading the picture, since progressive loading is ugly) but a future version may be display-independent.
More info here: https://github.com/peergum/Bitmap