Image variations not always being generated

[cosmicsafari]

Hi all,

I am working on a site which involves a lot of image upload fields, 99% of the time it works perfectly but I have noticed that every so often image variations will be missing.

Like the original uploaded image is fine but maybe 1 or 2 out of the variations is just blank.

The variation files will appear within the assets folder but they will be just in name only without any actual image content.

Since its quite a random thing I am finding it rather difficult to figure out why this happens?

Any ideas?

[heldercervantes]

You're generating the variations with the API on the frontend, right?

This sounds like a memory limit thing. I've had sites crash when they got a bunch of really big images added to a page. Access that page after and the processing time is clearly noticeable. On extreme cases I got a timeout, but refreshed the page and since most variations were already generated from the previous attempt, the second try goes through.

This may help:
https://processwire.com/blog/posts/processwire-3.0.63-adds-client-side-image-resizing/ 

[elabx]

4 hours ago, heldercervantes said:

This sounds like a memory limit thing

I support this idea, has happened to me a lot and it's always memory, file size limits on upload or execution timeouts. 

[DaveP]

ImageSizerEngineIMagick is much more forgiving on large images than the default GD resizing engine, if you can make it available on your hosting. (And faster and all round better IMHO.)

[heldercervantes]

31 minutes ago, DaveP said:

ImageSizerEngineIMagick is much more forgiving

Well said. I've used it on my last project and was blown away by the results. Images turn out looking much better than with GD as well, without all that color banding crap.

[cosmicsafari]

Thanks everybody, much appreciated.

[OLSA]

In my last project I had a to import about 4000 images, and had problem with about 1200 images. Images uploaded (using API from frontend), but some of them doesn't had variations images. Problem was that PHP GD image resize engine is very strict, and if there is any problem with image (beginning and ending bytes of file) GD resize failed. More about my case and solution is here.