I am trying to use the ionic resources --splash command, I have a splash.png file saved in my resources folder, and it is 2208 x 2208 which is the advised size. But when I run the command I get the following error
“Invalid upload: unable to read uploaded image”
I have added the splash screen preference in my config.xml and added the cordova splashscreen plugin but it wont work 
Can anyone help me please?! 
I am having the same problem. I have all the right dimensions but my image isn’t being read. When I was first building my app I uploaded an older splash screen and it worked fine but now that i’m trying to change it after removing the old one I keep getting that error.
I just realized that the image I had was actually an Adobe Illustrator image. All I had to do was rename the image from .png to .ai and it worked!
For those wondering here is a quick explanation on the difference between the two:
.ai - Adobe Illustrator vector files are scalable both down and up.
.png - pixel files can be scaled down, not up.
@DaveGadders
I put the two files, icon (1024x1024) and splash (2208x2208) in png format, within the resources folder.
Run in CLI, “ionic resources” and get only:
icon and splash screen ionic generator resources
Any new file is generated, remain the initial example. What is missing?
Ionic -v
gives version: 1.3.20