[jcupitt]

I made an image viewer for large images:

https://github.com/jcupitt/vipsdisp

It should be fine with your huge PNGs. Internally it's a bit like a tiled map viewer, but it makes the tiles as you view the image with a set of background worker threads. It uses your GPU to scale and composite the set of visible tiles to your screen.

It uses openslide to let you view slide formats like SVS and MRXS, which might be handy. It also supports colour management.

[vanderZwan]

Oh that's amazing, thank you for sharing!