Jesus bleedin’ nuts! I’ve got reader-submitted questions coming out of my ears. I’ve had to backlog a few, so don’t worry, I’ll get to you. This next question is right up my alley.

Clutch wrote:
Q:

Here’s a question that may actually be within your realm of experience; I have a bunch of images I’d like to resize, smaller, for uploading. Is there an easy way to do this to many images at once, say, in photoshop? Or perhaps another, preferably free application I could get my grubby little hands on? Thank you, oh wise and gratuitous davebgimp!

A: Easy as your mom! I’m going to answer this a bit backwards by first addressing the issue of software. Yes, you can do this in PhotoShop or the slightly neutered and cheaper PhotoShop Elements. PhotoShop’s a great program. I use it daily at work, but it costs an ass-load so most people end up pimping out Grandma to buy it or they steal it. Personally, I think that for most users, especially those who are working primarily in an RGB (red, green and blue) color space — web publishing for example, it’s not necessary.

Another option is to take the free route. There’s a few more steps involved but it costs several hundred dollars less… actually it costs nothing. There’s an Open Source, free image editing alternative called GIMP, which stands for GNU Image Manipulation Program. It’s available cross platform, so is accessible to anyone. I use it at home on Linux and having used PhotoShop professionally and otherwise for the past six or so years, I find it meets and exceeds all my home-use needs. Experienced PhotoShop users making the switch might get a bit annoyed at first, as I did, at the learning curve involved. I chalk it up to the fact of using one program exclusively for so long and getting used to the tricks and shortcuts and then trying out a new application with different tools, names and ways to get things done. But once I got past this (it was a quick transition), I found myself impressed and not missing much. If you’re new to either program, I highly doubt you will share this temporary and arguably unnecessary frustration.

The GIMP does have limitations in it’s lack of CMYK (Cyan, Magenta, Yellow and Black – a color space normally used with professional printing and presses) support and a rather huge learning curve if you want to install some plug-ins and know nothing about compiling from source code. Unless, you’re designing for print on a professional scale, you won’t be missing the CMYK support though. I have heard that there’s a CMYK plug-in available, but as of the latest version, the color space is not natively supported. No biggie for me or you other average home users. As far as having to compile programs for GIMP plug-ins, if you’re using Linux, you either know how to do this, or could stand to learn for your own good.

You should at least check out the GIMP. Since it’s free, you don’t have the problem of shelling out for a program that updated with a new version almost yearly (which means more $$$ or more pirating if you want to keep up with the latest). GIMP will always be free of charge and there’s plenty of documentation, tutorials and communities to help you get the hang of it, or you can always ask daveb.

Now, on to the first half of your question. I’ll explain how to do batch resizing with both PhotoShop and the the no-cost method. Let’s start with PhotoShop.

How to batch resize images with PhotoShop

First off, I’m writing this tutorial with PhotoShop CS2 in mind, since that is what I use at work, but I’ve used PS since 5.0, so if you’re working with an earlier version of the program, as far as I can remember, the steps are pretty much the same, so you should be able to do this.

Before you begin, put all the images you need to resize into a folder. If you’re a bit uncomfortable, make a backup copy of it, so if you screw the poodle, no one ends up crying.

1. Open PhotoShop
2. Select File>Scripts>>Image Processor
3. In the new dialog window, select your source folder in the top section and your destination folder below that. I’d recommend creating a new folder for your destination, thereby avoiding overwriting your original files in case at first you’re not happy with the result, you can go back, tweak and try again.
4. In the next section, set your desired quality pixel dimensions and file type. you’ll see a box marked Save as JPEG. Check that off if you want to make JPEGS, otherwise PhotoShop will retain the original file type. As far as quality goes, it’s up to you. You might want to experiment by manually resizing a few images and trying different qualities to see what suits you. Personally, I never go below 30%.
5. Click Run to start the script and watch the magic.

How to batch resize images for zero fucking cash

What I’d suggest if you’re going to take the free route is to install GIMP (because you need an image editor) and then use one of a few other programs I’m going to suggest to handle the resizing. I’d walk you through writing a batch script for GIMP or how to compile a plug-in to handle batch resizing, but I’m afraid it’s more work than I’m willing to do and I’d bet you don’t have the attention span to put up with it since you read this blog. If you want to take a crack at it, this plug-in is pretty popular, but since I’m going to assume that not every reader is using Linux like me, it’s just better this way, I think. GIMP is cross-platform, like I mentioned, so get that. Once that’s settled, here are some viable options:

For Windows:

1. MS Power-Tools Image Resizer: Microsoft actually makes a batch resizer as part of it’s Power-Tools collection. It’s from the corporate devil itself, but as I understand, it works well enough and allows you to batch resize photos with a simple right-click. You can find this program on this page.
2. Picture Resizer: A freeware tool for batch resizing of JPG pictures and photos. It has a drag-and drop GUI. Link.
3. Visualizer Photo Resize: Yet another freeware tool. Available here.
4. PIXresizer: Free, free, free. Not a penny charged. Get yours now.

There others out there, but one of those should be work for you.

For OSX:

1. ImageMagick: A command line application, but incredibly powerful. It’s open source and can be downloaded here. See it’s entry under Linux below for more information.
2. Dropic!: This is a drag and drop app, but limits you to a choice of only a few sizes. It’s free and is located here.
3. iResize: Batch resize and compress images in TIFF, JPEG, PICT, GIF and PSD formats. Also free and can be grabbed up here.
4. Resize!: I don’t know too much about this one, but apparantly it works, is free and is here.

For Linux:

1. ImageMagick: A free software suite to create, edit, and compose bitmap images. It can read, convert and write images in a large variety of formats. Images can be cropped, colors can be changed, various effects can be applied, images can be rotated and combined, and text, lines, polygons, ellipses and Bézier curves can be added to images and stretched and rotated. It’s a command line application and often comes bundled with Linux distros, so chances are you might already have it. It’s very popular and highly regarded as well as open source. The project page can be reached here.
2. bbips: A menu driven bash script that uses ImageMagick to “batch” process entire directories of images all at once. Go here.
3. Picwiz: A simple picture resizing wizard that is meant to be called from a Konqueror context menu (for KDE users). Here’s a link to the SourceForge project page.

I could go on forever. Each OS has a many more to choose from, but these should be enough to get you started. Personally I use the ImageMagick/GIMP combo and couldn’t be happier. By all means, feel free to suggest other options via comments on this post as long as they’re free and preferably open source.

[Ask daveb anything! Either use this form or send an email to webmaster [at] davebgimp [dot] com with “Ask daveb” as the subject line. Remember, daveb knows all!]

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