Re: help with gm mogrify

On Fri, 7 Jun 2019, mick crane wrote:

> On 2019-06-07 07:52, mick crane wrote:
>>> Is some combination of "-resize -extent -gravity -size"
>> I missed out "-background"
> OK graphicsmagick website still resets but I found it in /usr/share docs so I 
> think I can sort it from those pretty good instructions.

I don't know what you mean by "website still resets" but you are on 
the right track that you can use the -extent option to create a fixed 
size canvas to put under the image.

This is an example from the documentation:

           This command reduces or expands a JPEG image to fit  on
           an 800x600 display:

               gm convert -size 800x600 input.jpg \
                         -resize 800x600 -background black \
                         -compose Copy -gravity center \
                         -extent 800x600 \
                         -quality 92 output.jpg

The -size option improves read performance from JPEG files if the 
desired size is smaller than the pixel dimensions of the JPEG.

Bob
-- 
Bob Friesenhahn
[email protected], http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/
Public Key,     http://www.simplesystems.org/users/bfriesen/public-key.txt