Pix2Pix image processing commands with ImageMagick and Montage

pix2pix-imagemagick.md

Image Processing with ImageMagick

Grid of Images to Individual Images

Given a grid of images, generate single images

• Install imagemagick
• Run the convert command:

convert image.png -crop 2x3-8-8@ +repage +adjoin tile-%d.jpg

where:

• image.png is your screenshot file name
• 6x3 is your grid layout
• -8-8 is the amount of horizontal and vertical padding around each image
• tile-%d.jpg will be the name of each image, with a number appended for each one generated, replacing the %d (e.g. tile-1.jpg)

Individual Images to Image Pairs

Given a directory of single images, generate side-by-side image pairs for pix2pix model generation using montage:

montage tile-*.jpg -tile 2x1 -geometry 418x418+0+0 multi-%d.jpg

where:

• tile-* is the repeatable name of each image in the directory (e.g. tile-1.jpg, tile-2.jpg, etc)
• 2x1 creates sets of images with 1 row and 2 columns
• 418x418 is the dimensions of each individual image
• 0+0 is the amount of horizontal and vertical padding you want in between each image (we don't want any)
• multi-%d.jpg is the output file name for each image pair.

Test Images with Blank Pair

For generating new images, we want to run pix2pix on a test set of images with a blank image as its pair:

for i in *.jpg; do
    convert \
       ${i} \
      -gravity west \
      -background white \
      -extent 836x418 \
       $(convert ${i} -format "pair-%t.%e" info:)
 done

where:

• i in *.jpg loops through all of our jpg images in order to run imagemagick's convert command
• ${i} becomes the placeholder for that image path
• -gravity west \ implies we will be expanding our image canvas to the right (our image will be on the left / west side)
• -extent 836x418 \ gives the final desired dimensions of our images (418x2=836 pixels in width)
• $(convert ${i} -format "pair-%t.%e" info:) runs the actual convert command, generating images with a name like pair-1.jpg where %t is the iterator, and %e is the extension