Quickly tiling book cover images on my Mac for this new background

I wanted to tile a bunch of book images into an image that I could use for this blogs background with the least amount of work possible. I suppose that this background would have come out a lot better if I had taken the time to make the images all the same size. Oh well.

On my MacBook, where I have already installed ImageMagick for ebook conversations, I downloaded 12 covers from my recent Goodreads books. Using "append +" I combined sets of 4 images into 3 horizontal rows, then using "append -" I combined the 3 rows vertically into the single tiled image seen below. When I get inspired I'll do this with images that are all the same size.

Here are the commands:

$ ls
10377600.jpg 14114017.jpg 25018779.jpg 40507810.jpg
10772831-2.jpg 173984.jpg 25792353.jpg 7134155.jpg
12754117.jpg 2466753.jpg 37847394.jpg 9280898.jpg

$ convert +append 10377600.jpg 14114017.jpg 25018779.jpg 40507810.jpg row1.jpg

$ convert +append 10772831-2.jpg 173984.jpg 25792353.jpg 7134155.jpg row2.jpg

$ convert +append 12754117.jpg 2466753.jpg 37847394.jpg 9280898.jpg row3.jpg

$ convert -append row1.jpg row2.jpg row3.jpg tiled.jpg

and the results: