forum.coppermine-gallery.net

No Support => General discussion (no support!) => Topic started by: TerryG on March 30, 2005, 07:58:20 am

Title: thumbnail is much bigger than it should be?
Post by: TerryG on March 30, 2005, 07:58:20 am

Hey All,

I just noticed something odd, that I'm hoping someone can explain to me....

We're overruning our bandwidth on our gallery site, so I started looking at the elements on the page and checking out their size.  We have the thumbnails shown on the filmstrip, and they are sized at be around 100 pixels tall.

I'm seeing some of the thumbnails to be outrageously big.  For instance one called Window, is 66x100 pixels and the jpg file, on disk is 32KB.  Loading it into photoshop, I can check its statistics and see tha it is 66x100 pixels at 16 million colors = 19.3 KB in memory.

And if I save it, using the least amount of JPG compression allowed by photoshop, the file on disk is 6K.

So why is the file, on disk, so big?  We're using ImageMagick, and the JPEG Quality was set at 75 (we've lowered it to 50) and we are creating intermediate files.   The only command line option being passed to IM is -antialias

Any suggestions or thoughts would be appreciated.  

Terry

Title: Re: thumbnail is much bigger than it should be?
Post by: TerryG on March 30, 2005, 05:22:34 pm

It was EXIF data that was causing this! I added -strip to the ImageMagick command line options to explicitly remove EXIF data and that seemed to clear it up.

Then, of course,  I found another thread here that talked about this.  Why it didn't come up on my original search (before I posted the question)  is beyond me!

:)