I don't know about under the BB markup language, but I do know my blog software can do it for me; WordPress is pretty simple, merely adding at least one of the dimensions as a query in the url. For instance, the gay icon in the header image.
The official image dimensions are 1000x375:
bdthisis.files.wordpress.com/2014/12/putin-expression.png. Forum software scales the image to fit it into our style sheet.
However, I can also assign a simple dimension:
The above display is scaled in the image link:
bdthisis.files.wordpress.com/2014/12/putin-expression.png?w=300, setting the image width to 300 pixels; the image scales appropriately.
I don't know the rules for how that particular format works; it seems specific to the server software. My Picasa/Google image drives do seem to have dimensions written into urls, but I haven't figured out how to manipulate that.
Then again, since I've taken to various stylistic outcomes, I tend to customize most of my blog images; the black and white suits the page layout, and the added noise is just something I do. Many of the images I use are simply cropped to run unscaled:
Image credit: Detail of cartoon by Adam Huber, 17 December 2014.
(
bdthisis.files.wordpress.com/2014/12/huber-20141217-bugmartini-detail.png)
Most commercial web software automatically scales, like we see at Sciforums. Even the former software could. But there were some images that didn't scale properly, and I never did figure out what the deal with those was. And I'm pretty sure I can force an overwide picture by setting the query above our column width, but those manipulations are in the address, and I'll run a test later, so as not to mangle up the display of this thread if it works.
Oh, or you could
skip to this part:
BBcode.org on posting images↱, though ... I guess we can test ... and my first test failed. I'll try again to be certain that none of the markups work. (I tried [
img width="300" height="116"]...
url...[
/img].)
