Cropping Images

[Michael_Morris1]

@jaco_nel007

Howzit guys,

Any one know of a way to crop an image from the center of the image in php? What I want to achieve is to take an uploaded photo and create a thumbnail of a certain size from this. The problem is that a use can upload a image of any dimension.

I know it is possible to crop an image, but would like to get some comments on the approach.

Here is my idea.

1. Determine the width and height
2. From the width, determine the middle
3. From the middle, subtract half the desired width. This will give me my x coordinate
4. do the same for my height to get my y coordinate
5. Crop from these coordinates.

Any body know of a better idea, as this seems a bit messy.

I’ve posted a class that pretty much does this on the forum, though it rescales the image first, then crops to get the proportions right.

Computationally cropping without resizing will not work most of the time. The computer has no way of knowing what the compositional elements of the photo are and is going to end up cutting through faces a lot of the time. By rescaling first you can avoid some of this problem, but the solution still isn’t as idea as having the user do the resize first in photoshop.

That said the class is small and touches on the basics of manipulating images using the built in imageMagick library, so it’s a good learning tool.