Pseudocode, since I don't have ImageMagick installed here. 
# load original image (lena.jpg)
# get original image's geometry
# do
#    inflate dimensions by 1.2*
#    resize image to target geometry
#    add a little scatter noise to the image
#    set target quality to a high number like 99
#    save target image (lenna.jpg) to disk
# while (target image file size is too small);

[download]
The scatter noise and quality numbers are to frustrate jpeg's compression as the image grows.

Are we talking gigabytes of disk space? I think jpeg as a format will break at 2^15 (or maybe 2^16) pixel dimensions.

--
[ e d @ h a l l e y . c c ]

In reply to Re^4: How to create JPEG of specified size by halley
in thread How to create JPEG of specified size by Limbic~Region

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