PNG to TIF conversion with extra colour channel

[Lev]

Evening all,

We're using IM to convert PNGs to TIFs, while trying to maintain transparency. Currently the command used is:

Code: Select all

convert file.png -type TrueColorMatte file.tif

We recently started adding a custom extra channel to our PNGs. We are able to manually (using Photoshop) save our PNGs and even TIFs with this extra colour channel, but it seems like when we convert using IM, the extra colour channel gets dropped.

Question is, how would we convert and maintain the colour channels, while still keeping transparency?

Am a little bit stumped on this one!