Tips for Editing Product Images

Composition

Gordon Food Service has a nice guide for packaged and raw products. https://www.gfs.com/files/pdf/literature/gfsphotographystandards.pdf

Create Outlined Image in Gimp

If you don’t have proper lighting and backgrounds, it might be best to use an outline image with transparent background.

1. Open in Gimp
   1. Layer
      1. Transparency
         1. Add Alpha Channel
   2. Scissor Tool
      1. Check Antialiasing
      2. Check Feather edges (8)
      3. Check Interactive Boundary
      4. Zoom in on Image
      5. Start clicking boundary points
      6. Click on the starting boundary point when done
      7. Click in center of scissor area to select it
   3. Click the Select Button
      1. Invert
      2. Click the Keyboard Delete Button to delete the background.
   4. Image button
      1. Autocrop Image
   5. Save a .xcf file for future editing
   6. Export a .png file for use.

Rotating Images in Gimp

1. Tools Button
   1. Transform Tools
      1. Rotate

Trim or Autocrop Alpha Channel with ImageMagick

This automatically crops images from a transparent alpha channel background.

mogrify -trim +repage *.png

• mogrify is an ImageMagick command to modify images by overwriting the original. Make sure you have a backup.
• -trim trims image edges.
• +repage is needed or the command will cause offset issues. +repage removes/resets the virtual canvas meta-data from the images. See more here
• *.png applies actions to and overwrites all .png files in the folder.

Resize Edited Photos With ImageMagick

Simple resizing.

mogrify -resize WxH *.png

• mogrify is an ImageMagick command to modify images by overwriting the original. Make sure you have a backup.
• -resize WxH resizes an image to W px in width and H px in height.
• *.png applies actions to and overwrites all .png files in the folder.

To create images with the same canvas size. (useful for thumbnails or other such needs.)

mogrify -gravity center -background transparent -extent WxH *.png

• mogrify is an ImageMagick command to modify images by overwriting the original. Make sure you have a backup.
• -gravity center centers the image inside the transparent background.
• -background transparent makes the resulting canvas transparent.
• -extent WxH Sets the canvas size to W px in width and H px in height.
• *.png applies actions to and overwrites all .png files in the folder.

Reduce File Size using PNGCrush

for file in *.png ; do pngcrush -brute "$file" "${file%.png}-crushed.png" && mv "${file%.png}-crushed.png" "$file" ; done

Delete Files with Name Containing “foo”

# try without -delete to see what it will apply to.
find -type f -name '*foo*' -delete

Rename Files by Appending “foo” to End

for file in *.png; do mv $file "${file%.png}-foo.png"; done

Rename Files by Removing “foo”

# "-f" to force rename files in current directory
rename -f 's/foo//' *.png

Rename Files Based on csv File

Will rename all files in folder from the first files.csv column name to the second files.csv column name. Useful when combined with the duplication script below. Based on http://askubuntu.com/a/438580

sed 's/"//g' files.csv | while IFS=, read orig new; do mv "$orig" "$new"; done

• sed 's/"//g' files.csv will remove the quotes
• IFS=, split the input on “,”
• while read orig new; do ... done will read each input line, split it on the value of $IFS (a comma) and save the 1st field as $orig and the rest as $new
• mv "$orig" "$new" will rename the files as requested

Duplicate a File N Times

This will duplicate foo.png N times and name the files sequentially: foo-001.png, foo-002.png, … foo-N.png.

for n in {001..N}; do cp foo.png foo-$n.png; done