I was lucky enough to organize my elementary school reunion recently, the class from 36 years ago. During the reunion, we tried to take a picture from our old yearbook. It looked fine at first glance, but many spots turned out to be either trapezoid in shape or completely distorted, so I decided to use a 2D image editor to fix it, and I’m hoping to achieve the result shown below. (Image has been blurred to protect privacy.)
Before
After
There are plenty of tutorials about editing photos on the Internet, and I found a Photoshop tutorial made by Flycan.com(【飛肯設計學苑】教學與分享 Photoshop 教學 – 自由變形 – 修正超廣角鏡頭的變形照片). I followed the instructions and tried to edit by myself, and below are the before and after pictures:
Before
After
I found out that this tutorial only teaches you how to edit distorted photos on a very generic scale. To fix specific portions of various distortions, you still need to use other Photoshop features that aren’t mentioned in this tutorial. Technically, I could keep exploring other features in Photoshop to get the job done, but I had something else in mind. If you think about it, a distorted photo is not much different from a distorted rectangular 3D model on a surface, and this photo I was trying to edit, was the texture to be mapped to this model. Since this texture was projected on a distorted surface, I decided to use the 3D modeling software I’m most familiar with, 3D MARS(六角大王軟體第 6 版), to make the photo normal again. These are the steps I took:
1、Load original photo as background.
2、Create a model according to the background and emulate a distorted surface.
3、The original photo displays portraits in an 11 by 6 array, so divide the model into an 11 by 6 table.
4、Fine-tune the lines so that they match the distortion on the original photo.
5、Load the original photo as texture, map it on the model and remove the background.
6、Adjust the distorted model into regular rectangles.
7、Examine the spaces between the portraits, and adjust the grid accordingly.
8、Once it’s done, save the 3D model as a regular high-resolution picture.
The whole idea is to transform a distorted 2D photo into a distorted 3D model, straighten all the UV coordinates, fine-tune the aspect ratio, and save the final 3D image into a regular 2D picture. It’s meant to fix serious distortions like that of a waving flag, instead of simple trapezoids that are supposed to be rectangles. It usually happens when you try to take pictures of the pages in a book from a camera angle that will inevitably make the image distorted. I just happen to know how to use a 3D modeling software, to apply the concept, and use the right features to restore the distorted image back to its original form.
The goods about this method:
- Unlike the traditional way of editing 2D images, all it takes is a little drag and drop of your original image to the right spots on a 3D model, and it won’t change the continuity of the original pixels.
- Not much traditional image editing skill is required.
- An image with multiple distortions can be adjusted through UV mapping as well.
The bads about this method:
- Mastery of a specific 3D modeling software is required.
- Once a 3D model is finished and ready to be saved as a 2D image, its resolution may vary according to which 3D modeling software you use, because after all, a 3D modeling software is not specifically meant for editing 2D images. The final finished image might have a lower resolution than its original distorted image.
For more paper models and tutorials visit Fun Paper.
