Nidhogg very correct about upscaling this much degrading an image, might not be so bad for an animation. All in the eye-of-the beholder.
A tutorial for Gimp 2.10 - not much different from Gimp 2.8 - more ways than can be mentioned
![Wink ;)](./images/smilies/icon_wink.gif)
One way.
Image -> Scale image brings up this: Depends on the original image but a little calculation gives 360% as a value that gives the correct height but not width. You can do by trial-and-error or just setting the height in pixels, the width and height are linked so changing one value affects the other. Set the interpolation to NoHalo (or Sinc for Gimp 2.8) and click Scale.
Attachment:
01-resize.jpg [ 84.38 KiB | Viewed 12421 times ]
To give a fit for the phone
Image -> Canvas size resizes without distorting the image. The essentials are: Set the width to the new size (2560) in pixels. Note the link between Width and Height is broken.Then click on center which gives a uniform offset, choose all layers and Foreground colour (black) (this is an improvement on Gimp 2.8 where you need to set the background swatch) Click on resize.
Attachment:
02-resize.jpg [ 82.79 KiB | Viewed 12421 times ]
Guessing at least 22 images to adjust. The above can be applied in one go to an image with layers.
File -> Open as Layers to choose and open all of them.
Apply the above exactly in the same way.
To avoid having to export each layer individually an old Saul Goode script attached.
Unzip, goes in C:\Users\"yourname"\AppData\Roaming\GIMP\2.10\scripts. Find it bottom of the File menu.
Actually you do not need to do this, Keep the layers and go straight to File -> Export. Export as an animated gif.
(Wonder if Gimp 2.10 webp animation format works with an Android phone?)Edit: Shows how little I know about phone (hate them) a little look around and separate images needed
https://forum.xda-developers.com/showth ... ?t=1852621Maybe that old script will come in handy after all. Dump images in the Windows user folder As:
https://i.imgur.com/woyODgM.jpg