Retouched images don't compress well?

nysus

Joined: 2005-05-15
Posts: 16
Posted: Mon, 2005-05-16 12:30

I've just noticed that photos I've retouched do not compress very well. I have photos that are approximately 3700KB at 3000px by 2008px. These are photos that I've retouched by boosing the contrast/saturation/sharpness, etc.

When they are reduced in size, to 640x426, and compressed, quality level set to 75, they only get reduced to about 2200KB. That's pretty large.

By comparison, unprocessed photos get reduced all the way down to 70KB.

I'm wondering what other people's experiences are with this and if any one can shed some light on this phenomena. Would moving to GD improve results for me?
----


Gallery URL (optional):
Gallery version: 2
Webserver (with version): Apache, 1.3
Datatabase (with version): Mysql, 3.24?
PHP version (eg 4.2.1): 4.10
phpinfo URL (optional):
Graphics Toolkit(s): imageMagick
Operating system: Windows XP
Web browser/version: Firefox
G1 version (for migration bugs):
 
nivekiam
nivekiam's picture

Joined: 2002-12-10
Posts: 16504
Posted: Mon, 2005-05-16 14:19
nysus wrote:
I've just noticed that photos I've retouched do not compress very well. I have photos that are approximately 3700KB at 3000px by 2008px. These are photos that I've retouched by boosing the contrast/saturation/sharpness, etc.

When they are reduced in size, to 640x426, and compressed, quality level set to 75, they only get reduced to about 2200KB. That's pretty large.

Which program are you using to make these modifications? Are you performing the editing then uploading to Gallery and then resizing the images or are you doing all of that in your program on your desktop?
 
nysus

Joined: 2005-05-15
Posts: 16
Posted: Mon, 2005-05-16 14:28

I started a new thread on this which compares my results with ImageMagick to GD. See http://gallery.menalto.com/index.php?name=PNphpBB2&file=viewtopic&p=139745#139745

My workflow is as follows:
Open photos with Nikon's PicturePerfect software
Do a quick autoenhance and do some manual tweaking of the photo in PP.
Drag and drop the enhanced photo from PP into GR.
Upload photo to server and let it do the resizing.

But all this is moot. Because if I upload the SAME picture from PP to Gallery using ImageMagick, it is almost 100x the file size if I use the GD toolkit (see link above).