How to stretch the edge of a picture.

[enginestar]

Say I crop a picture.
On the left I have an edge that is 5 pixels - after my object.
I want to have a border around my object be 20 pixels say.

How can I stretch the edge and make it 20 pixels?
I used to do this in Photoshop.

As an example see the image below


Say I want to stretch the left hand side.
Ignore the shadows! This is just an image I took off the internet to help ask my question!

Thanks.

[Blighty]

1. Image>Canvas Size and increase size by 15 pixels
https://imgur.com/a/kVPoTOK

2. Right click on layer and Layer to Image Size

3. Make a selection on the left edge of the image
https://imgur.com/a/EyrqtUr

4. Use the Scale Tool to stretch the selection to the left.

5. The scale tool creates a new Floating Selection in the layers dialogue
https://imgur.com/a/smqWgWO

6. Right click the floating selection and select To New Layer

7. (If necessary - use the Move Tool to move the new layer 1 pixel to prevent a gap between the two layers)

8. (If necessary - use Layer Masks to blend the two layers)

[rich2005]

No info on your OS but another way is seam-carving using a Gimp plugin liguid-rescale

see: http://liquidrescale.wikidot.com/

briefly: Paint in a 'keep' mask. Set the new width. Apply and hope it comes out the way you want.

Looks like: screenshot https://i.imgur.com/YJQv9wX.jpg

gives

[Ofnuts]

Also, with the resynthesize plugin:

- Image>Canvas size, add width and drag the image to the right
- Layer>Layer to image size
- Filters>Enhance>Heal transparency, select appropriate sampling width (more or less the current margin) and tick Inwards towards center 

   

[enginestar]

u guys are awesome.
trying out all solutions given above now.
THANKS

+ i will add in signature what my OS is