Using filtered photos for backgrounds is a common technique used in amateur/freeware visual novels to keep the required art assets down. In this post I’ll try to explain some of the techniques that can be used for photo editing. I’m using Photoshop filters and terminology, but the methods should be applicable to any image editing program.
Step 1: Get the picture
The first thing you need is a good base photo for editing. Sometimes you’re able to take the photo yourself, but most of the time that’s impossible or unpractical. If you need photos of exotic locales or ancient architecture, vacation pictures can be a good source. In most cases, public domain or other royalty free photos will be your primary source. Here are some sites to help you on your way:
Since we’re going to apply some heavy filters later on, it’s okay to upscale a low-resolution picture. Sloppy/bad photo editing is masked by the filters in the same way, so don’t be afraid to paste objects from one photo into another even if your photo editing skills aren’t exactly up to professional standards.
Step 2: Clean it up
Color correct the image as needed. Changing the color/contrast can greatly improve bad photos or add a certain mood to them. The example pic above was way too dark so I increased the brightness, then increased the brightness and saturation of the bottom half some more.
Tools to try out:
- Image → Auto tone/contrast/color (easy fix for small color correction)
- Image → Adjustments → Curves (change contrast, color balance)
- Image → Adjustments → Exposure (overexpose areas for a bloom-like effect, change gamma)
- Image → Adjustments → Hue/Saturation (Color tint areas, alter saturation)
If the horizon is tilted (common in photos taken by non-photographers), rotate the image to correct it. Then, crop the image such that the horizon is where you want it (usually between 1/3 and 1/2 from the top). Use a (placeholder) sprite and an image of the textbox as a guide to help you see what looks weird.
Upscale the image as needed. Depending on the type of filtering you want to use later, you may want to downsize images that are too high res as well. Some filters or filter settings are resolution dependent, scaling all images to the same size helps keep the filtering appear consistent.
Next, it’s time to clean up the image. Remove any logos, people and other distracting elements (healing brush, content-aware fill). It’s okay if it looks kinda shitty, the filtering later will hide it. In the above image I removed some of the smaller clouds using the these techniques. A surface blur on the sky removed some of the unwanted small details on the clouds.
Step 3: Filter time
Consider if you want to use the same or similar filtering for the entire VN, or if you want to vary the filtering based on mood or whatever method looks best for each photo. What filtering to use is largely a matter of taste. Here are some of my favorites filters:
angled strokes (direction balance=50, stroke length=15, sharpness=3) dark strokes (balance=5, black intensity=6, white intensity=2)
Good general purpose filter, works on most backgrounds. The blackness/thickness of the dark strokes may need to be varied depending on how dark the background is.
Sumi-e (stroke width=9, stroke pressure=1, contrast=1) Surface blur
Nice alternative to dark strokes. Can become ‘messy’ on images with sharp contrasts or a lot of detail.
[layer1, blend mode=overlay] Colored pencil (pencil width=3, stroke pressure=15, paper brightness=50) [layer2] Gaussian blur (radius=64)
Remember that the currently selected color changes the background color of the colored pencil effect. White seems to work best. Setting the blend mode to overlay on the top layer fills in the white parts with the blurred second layer.
sponge (brush size=5, definition=0, smoothness=5)
Gives a painted effect to the image. Works best on images with small details and few straight lines (those become distorted by the sponge effect). Can be used by itself (left) or combined with the 2-layer setup as used with the colored pencil filter (right).
Experiment, experiment, experiment — find out what looks good for your VN. Don’t just blindly apply some crappy posterize effect and call it a day.