imagecrunch is a simple, blazing fast tool for rendering an image file at many
sizes. imagecrunch can also crop, convert between formats and automatically
rotate photos so that they will face the right way in all web browsers.
imagecrunch relies on native MacOS X APIs, which is why it is less than 300 lines of code and the binary is about 15K. It is also why it is very fast.
Click here to access the latest releases on github. Click the green download button for the newest release.
Once the file arrives, copy it to /usr/local/bin or your preferred location and mark it executable:
cp ~/Downloads/imagecrunch /usr/local/bin
chmod 700 /usr/local/bin/imagecrunch
Feel free to build the xcode project instead. We welcome pull requests but do want to keep this tool really, really simple.
Let's scale an image to three different sizes with one command:
imagecrunch original.jpg -size 300 500 -write small.jpg -size 500 700 -write medium.jpg -size 1200 800 -write large.jpg
Images are never enlarged and never distorted. If you specify -size 300 500 you will get the largest image that fits in that box without changing the aspect ratio, and without enlarging the original.
(Both would look terrible, so we don't do them.)
Now let's crop to fetch Jane's head from the team photo:
imagecrunch team.jpg -crop 350 300 100 100 -write jane.jpg
The arguments to -crop are: x, y, width, height.
You can use -size and -write as many times as you want. You can only use -crop once. This is a good thing: crop the original the way you want it, then output the result scaled to lots of sizes.
Oh yes, we can get information about a file:
imagecrunch -info flower.jpg
Might generate this output:
{
"extension": "jpg",
"width": 1936,
"height": 2592,
"originalWidth": 2592,
"originalHeight": 1936,
"orientationCode": 6,
"orientation": "RightTop"
}
Yes, it's valid JSON. Just call JSON.parse() in your scripting language of choice.
extension always tells the truth: it's based on what is in the file, not the original file extension, which could be a lie.
width and height are the size of the image after orientation is taken into account. originalWidth and originalHeight are the size of the image before orientation. orientationCode and orientation are... for people who get really excited about EXIF. For everyone else, just know that we automatically rotate images when we load them, so all the images you -write will always face the right way in every browser.
1.0.0: initial release.
On Linux or Windows we suggest using Imagemagick, which can do much, much more, although imagecrunch is a lot faster.
You can also run Imagemagick on a Mac if you use macports or homebrew.
"What about sips on the Mac?" The built-in sips tool is nice, but:
- It can't remove JPEG orientations to make photos face the right way in every browser,
- It can't crop an arbitrarily chosen portion of an image, and
- It doesn't support separate limits for width and height.
It's a nice tool, but we really need those features. If you don't, type man sips sometime.
Created at P'unk Avenue.
