Ah. I also came across this issue and wanted to ask a new question, but it seems that it's not really a "problem" but rather a lack of functionality.
While
@hdghule's use case might be a bit strange or unusual, in my case, I'm generating images automatically for RSS feeds coming from Blogger (among other platforms — but Blogger is a good example). As mentioned by
@Temyk, the plugin doesn't deal with such images, but, interestingly enough, when
manually adding a new image, and looking at the popup that shows all images detected on that page, those images from Blogger
do appear perfectly!
In other words: it's obvious that APT
can display those images, it just doesn't seem to be able to
process them in some form, and therefore this process fails. Unfortunately, even though I have text-based image generation active as a fallback, in these cases, APT does
not use it. Instead, it
seems to attempt to use the image — since it
is an image, after all! — but somehow fails its processing, and probably gives an internal error of some sort (not even with
WP_DEBUG
set to
true
anything is shown, so this is just a conjecture) which prevents further processing; that article will remain "forever" with a
No image setting, unless, of course, I download the image from Blogger and upload it on WordPress
manually — thus defeating the purpose of having an
Auto Post Thumbnail plugin
Note that this doesn't happen only with Blogger (or
@hdghule's example). The same happens very often with all sorts of external images stored on CDNs — notably, Automattic's own CDN,
Site Accelerator/Photon (or whatever they call it these days). The observed behaviour is the same: the image never shows up as being
automatically generated, but APT doesn't fall back to a text-generated image, either.
Running the auto-generate option manually doesn't help, either; the result is precisely the same.
Sometimes (very rarely, and in difficult-to-reproduce situations), it
is possible to get a "semi-automatic" generation. This works in the following way: on the Posts list, at the top, filter it for
With Image (this is counter-intuitive, I know), and check all boxes for posts that show
No Image. Then go to the
Bulk actions operations dropdown and select
Generate featured image. Again, as said: I don't have any idea why
this works, and with which types/kinds it works, but at least it's faster than going through each image individually, clicking on
No Image, and manually selecting a (valid) image...
There is a catch, though. Unlike the
Generate images tab from the settings, which is specially programmed to deal with long processing times and will
not timeout, the same is not the case with the method described above, since it goes through the built-in WordPress mechanisms — which
are subject to timeouts! As such, depending on the speed and processing power of your server, and on the timeout settings, you might only be able to generate a few dozen images on each run. It's not as if you can display, say, 200 posts at a time, check them all, and hope that APT will generate all the images! That won't work at all. But I often manage to get, say, 20 autogenerated images at a time, before the timeout inevitably occurs — which is, in any case, much faster than doing it
manually, one by one. And, as said, this will
not work with
all images, but it seems to be rather more successful than the other built-in mechanisms...
Perhaps there is a clue here for the plugin developers to figure out why APT does seem to hiccup with images stored on CDNs but
not when it's called from the
Bulk actions?... clearly,
something is done differently in each of those cases, and knowing where it
seems to be done correctly (at least, for most cases!)
might help to get it working on the other places as well.
_______________
(Note: I'm a lifetime premium user, and never regretted my choice of this amazing plugin!)