How to 'gradient out' to white?

[enginestar]

Let's say I have an image.
I roughly cut out leaving a border of 20-30 pixels say.

How can I have the border of the image stretch out to the edges of the picture and blend into white?

See the image below. I intentionally kept the picture dark to illustrate what I want.



I've never seen it done anywhere - but I can't see why it wouldn't be possible?

Thanks.

[Ofnuts]

• Layer >Transparency>Remove alpha channel (if greyed out, it's already done)
  
• Use the Measure tool to evaluate the minimum distance between the shoes and the current white background (around 30px in the image you posted)
  
• Use the Wand tool to select the white
  
• Select>Grow by half the margin measured above (15px)
  
• Select>Feather by the margin measured above (30px)
  
• Edit>Clear or [delete]
  

   

[rich2005]

another way

There is at least one plugin to do this, however using standard gimp tools, maybe something like this.

Uses layer masks. see: https://docs.gimp.org/en/gimp-layer-mask-add.html & https://www.gimp.org/tutorials/Layer_Masks/

Isolate the foreground using a black layer mask and painting in white screenshot: https://i.imgur.com/QxQA0rF.jpg

You need a layer the same colour as the area around the subject. Add a white layer mask fill with a white-to-black radial gradient
screenshot: https://i.imgur.com/dM80iNA.jpg (although you could equally paint a gray-to-white gradient. Depends on the background.

All that goes over whatever background you have (in this case white)



edit: slightly improved the gradient layer. The great thing about a layer mask is the ability to'tweak' it.

[enginestar]

guys, i never replied to this thread.
awesome - thanks a million for both replies.
i'm loving using gimp - especially the new shiny looking version.