With ImageMagick installed, 
system("convert xc:white -geometry 200x200 output.jpg");

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or 
my $image = new Image::Magick(geometry => '200x200');
$image->Read('xc:white');
$image->Write('output.jpg');

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See http://www.imagemagick.org/script/perl-magick.php for more details.

If you want to READ a given file, figure out its size, and use that, then you will also want the following: 

my $original = new Image::Magick();
$original->Read('original.jpg');
$geometry = $original->Get('geometry');

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(The 'xc:____' is a "virtual limitless file" for input, kinda like /dev/urandom, except all pixels are of the named color. You can use #FFFFFF notation here too. Or supply an original image filename without the 'xc:' prefix.)

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

In reply to Re: 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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