I recently decided to repurpose a product and turn it into a book and Kindle version. The Kindle version had no real issues with images since they get down sampled anyway, but the printed book needed to have the images at at least 300 dpi (dots per inch). If not the images would almost certainly be grainy, and I don’t want that. Most screen capture software saves the images at 96 dpi or sometimes 72 dpi. I started using Photoshop and taking each image and making it 384 dpi by using the bicubic sampling functions. It was a pain. First, change the image type to indexed color, then upscale, downsize (the images get really big), then change back to RGB. Do that for 50 images, well, you get the idea.
My search for automated image manipulation
I started looking for a Photoshop script to do the work, and couldn't find one I thought was decent. Then I looked at some commercial programs, but I never did use them. Instead, I stumbled across irFanView. This program does everything I needed and more. I have only done the batch conversions, but you can also do many different things and there are plugins as well. I decided to put together a little video to show you how easy it is to use the batch functions of irFanView to increase the resolution of your screen captures for print. You could use this for any image really. Also, I highly recommend not using .jpg or .gif for your print work. Use .tiff. Tiff files are designed to be printed, and even though you don’t hear much about them, do yourself a favor and use them on all your print projects. Without further ado:
All right, I'm going to show you a little program here that I found because I was looking to convert a whole bunch of screen shots that I had. We're talking 30, 40, 50 of them in a batch. I didn't want to spend money for these one off jobs. I found a great little program called IrfanView.
Hit batch conversion or rename or you can just hit the B key. Comes up with another little dialogue here called batch conversion. This program does a lot of stuff.
The nice thing is, you can do pretty much everything in this batch conversion that I've found. I want to save as a tip, and just a hint to anybody that's doing any kind of real publication, whether it's a normally published book or you're using Create Space. You want to have at least 300 dpi images or they're going to look funny, may be grainy, and most screen captures do 72 dpi or dots per inch.
We'll go find a file folder that I'm looking to work on. Okay, so we see I have in here five jpeg files. What I'm going to do, the easy thing in my case, I have them all sorted out. I just hit add all but you can individually add them as well. I have them tip as selected as my file output format here and I want to hit advanced.
I've already set this up. I know that generally, things blow up better if they're doubled. If the screens are 72 dpi, you multiply that times five and that's where your target it. I've got 384 dpi and that's really all I've changed on this.
There's a lot of other things you can do. You can blur them, correct brightness, sharpness. With screen captures you don't really need to do that. You're just trying to blow them up and keep as much detail as possible and keep the same size. This does all this.
You could do it in Photoshop. It's much more tedious. I guess you can create some action to do it automatically but this is already here and it works great. You just hit okay, multiply your base dpi and all your screen shots should be the same by usually five, so you're over 300.
If you're over, that's okay. Just hit okay, so that's ready to go. If you want to see the options on the tips, I don't use compression just because I want to have the top quality for print. So you can hit okay on that. All you do here now is...
The nice thing is, if they're all in different directories like I do, each chapter has their own thing. You want to make sure they stay in the because I'm changing the extension any one in the tip from a jpeg. I can just hit this, use current look in directory. You noticed this changed right here or you could browse if you're going to keep the same name and you just want to put them in a high def or something like that, folder. In my case, it's easier just to hit the current directory here. Just hit start batch.
You can see they're done. I returned a batch because I'm doing a whole bunch. You can see they're all there ready to go, and that's about it.