Let’s walk thru how to use David’s Batch Processor add on for Gimp to batch process images in a snap! We’re going to focus on batch resizing of an entire directory of images but there are a lot of options available in David’s Batch Processor, such as turn, blur, color, resize, crop, sharpen, and rename. It will take some getting used to on all of the fine details under each tab but well worth the learning curve.
You can download and find install/troubleshooting information on David’s Batch Processor here. You can also send David a donation from that page if you want to send the good karma back.
Once you get it all installed, let’s get started! Open Gimp. On the main window menu bar you will go to Filters | Batch Process
Try to reign in your excitement when you see all the options tabs in this window. I’ll never admit to spending many a late nerdy nights trying out the options to “just see what happens”.
Ok, let’s add the directory of files we want to batch resize. Click the Add Files button.
You can select individual images or the whole range depending on which one’s you want to apply the resizing to. I usually click the top image, hold down the SHIFT button, scroll, and click the last image to select them all. If you want to select just individual images, use CTRL-ALT and click the one’s you want to add.
Once you have them selected, click Add.
So. You clicked Add right. And it looked like nothing happened. You will need to click the Close button to close this window.
You will now see your added files in the list. To resize all the images in the list, click the RESIZE tab.
Again, lots of options. For the purpose of this tutorial we’re going to keep it simple. Resizing can be relative to the input image size or an absolute size. Check the ENABLE button to “turn on” Resizing and check the box KEEP ASPECT locks the x and y sliders to the same value. Set the X and Y to .20, this will resize the images to 20% of their original size.
While it’s tempting to click the Start or Test button’s now, WAIT – we haven’t finished our settings! Click the Output tab and in the drop down area, choose JPG. You can modify the settings here as you’d like, increasing the Quality will increase each individual file size but sometimes that’s a good trade off. I went with a medium setting of 75.
Almost there so let’s click on the most confusing tab ever, the Rename tab. You’re just going to have to trust me on this one. If you really want to make yourself crazy, just try and figure out what clicking the Source Dir button does. I’m not going to torture you, so click the Select Dir and choose the same folder where the original images are. I like to add a prefix to my file names so they will be listed together, as you can see here a “t-” will be added to the original filename when it is resized.
Ignore what the path says after “Original:”. Honestly, you’ll drive yourself crazy trying to sort it. This is easily the most frustrating tab as one errant click here will generate a long and hard to understand error message. If I get that error, I usually close the batch processor and try again.
Click Start and the image batch processing will run until it’s complete. You’ve now got a whole set of original files and a whole set of resized images. Well done!
