PNG transparency not preserved

[vincenth]

I use PSP to modify PNG image files. For those images containing areas of transparency, when I attempt to resave the image (as a PNG file), I get a message that it must be saved in a "merged" format. I select Yes/Continue, and the resulting file is white in the areas that were transparent.

What options must I select to preserve transparency in PNG files?

[LeviFiction]

You should only have to do this once and the settings will stick until you want to change them.

Go to File->Export->PNG Optimizer

Go ahead and select the transparency tab and select how you want Paint Shop Pro to define the transparency. You can use specific colors or you can have it use the current transparent areas in the image.

When you hit Okay it'll go ahead and open the "Save Copy As" dialog. And you can save out from there. Once you go to save as a PNG again it'll use the last known settings for the optimizer by default so you won't have to use the optimizer again yourself.

The other way is when inside the Save As or Save Copy As dialogs is to go to the bottom right-hand corner and select the Run Optimizer button in there. It'll open the same dialog and allow you to edit the same settings.

[Tim Morrison]

Use the PNG Optimizer as LeviFiction has suggested and you will retain transparency, but you will still be saving a merged image... i.e. one that is a single raster layer. If you need to retain layers or vector objects you will need to save a PSPIMAGE copy as well as the PNG.