Date   : Thu, 26 May 2005 08:58:56 +0100
From   : Rob <robert@...>
Subject: Re: Picture and thumbnail sizes

At 11:57 25/05/2005, Jules Richardson wrote:

>On Wed, 2005-05-25 at 10:36 +0100, Rob wrote:
> > Just in case anybody else is like me and fed up with maintaining separate
> > thumbnail & image files, for our website (www.russianglass.co.uk - totally
> > OT) I ended up writing a dynamic module so the web server (apache) 
> would so
> > it for me.
>
>Does it cache the thumbnails on the server? Resizing a full-size image
>for every thumbnail every time is a pretty expensive op!

Actually it doesn't, though that's something I have thought about and is on 
the list of things to add 'sometime'.  In my specific case, the 'big' 
images are still <100K (mostly 400x320 jpeg) so the load when running even 
a page like http://www1.russianglass.co.uk/ebayall.php (100+ thumbnails) 
wasn't very noticable. (load average of about 1.0)

We don't get a huge amount of traffic, but it really needs responding to 
quickly - once I got over speed of database access, it's actually my 
upstream bandwidth that limits me most, so I wanted to reduce the size of 
the pictures sent. (it's all on dsl lines, so 256k up on www1, 512k up on 
www2.)



>I've ended up coming at this from a different angle, with my web-based
>gallery just being another 'view' on the existing original images I have
>on local disk (which are organised, backed-up etc.). I'm using a config
>file to generate each gallery once-only; the config file references
>original images and dictates any ops needed to produce the final gallery
>(rotations, cropping, resize etc.)
>
>I'm doing that mainly because I didn't want to have to keep my original
>images on local disk *and* a snapshot of any web content too; that
>seemed a bit wasteful when it's an automatic and quick process to
>regenerate the gallery from the config file and original images (and the
>website server's being backed up by the ISP anyway). I suspect a lot of
>people out there only take photos to put on their website though, so to
>them it wouldn't matter as the web view on things is the important bit!

I think similar .. actually the webserver is/are local, so the website home 
folders are NFS exported to a folder on the main (samba) server, and hence 
ultimately to a mapped drive on the windows machines..  so for a lot of 
pics, there is only actually one image anywhere, which is then used for 
local activities, and served up dynamically as thumbnails or bigger with or 
without watermarks added, etc.  Saves duplicating everything three times & 
always forgetting what's changed.. [actually, we do keep backups, plus the 
full size original images from the camera before cropping etc, too, but 
they don't get used too much.]



Rob.