Better Method for resizing images than GD1; 2? Better Method for resizing images than GD1; 2?
 

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Better Method for resizing images than GD1; 2?

Started by jsalab, March 03, 2011, 12:35:54 PM

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jsalab

Resolving the problem with poor quality photos compared to the photo scale, which has the same dimensions as the parameter "Max width or height for uploaded pictures" Thank you
CPG v1.5.9. the link is not important Thank you

Αndré

Not sure what your actual question is. You can use GD or ImageMagick to resize images in Coppermine.

jsalab

Yes, I have enabled GD v2. I found that the system reduces to upload photos to the size of 1200x800 to 1024x682, well it should be 1024x683. Also there is a blurring and loss of color saturation.

phill104

GD only resizes images if you tell it to. Take a look at the ettings in the config panel. If you increase the max image dimensions in the Coppermine config panel to a size larger than the images you are uploading then the image will not get processed by GD/IM with the exception of creating the intermediate/Thumbs depending on your setings. You can also adjust the quality of the resized imaged in the config panel.

Please take some time to read the docs regarding all the settings available.
It is a mistake to think you can solve any major problems just with potatoes.

jsalab

This is not a bad setup. I set it the way I want. We shoot your screen, it will be better than a text description.

Αndré

Quote from: jsalab on March 03, 2011, 08:11:22 PM
the system reduces to 1024x682, well it should be 1024x683
That's just a small mathematical rounding issue that can be 'fixed' in the core code.

phill104

You state you are running version 1.5.9. The current version is 1.5.12 so please upgrade.
It is a mistake to think you can solve any major problems just with potatoes.

406man

I agree with jsalab and will re-state what I see as the problem. Coppermine allows the administrator to set the maximum dimensions of an image. In my case this is the maximum size of the intermediate image. An image uploaded which is bigger than this gets re-sized by the GD library routines. The resizing gives a poor quality result. A sharp image ends up being quite fuzzy after re-sizing and some of the users of my gallery complained about the results. It's not practical to increase the maximum dimension settings because then the pages are too large to fit on the screens of some users without a lot of scrolling (I had complaints about that as well).  I don't know enough about the GD library to know if there are settings that will give a better result – for example a setting using the sinc or lanczos resizing algorithm.  There is a good explanation of this area on the excellent Cambridge in Colour site. As far as I can see my web host does not have Imagemagick available so unfortunately that isn't an option, although I would be interested to know what it is capable of doing. While I realise that USM is available to sharpen an image I'd prefer not to do that due to potential problems with halo edges and want to rely on a decent resizing algorithm.

To sum up, I'm looking for either:
- resizing that gives a better quality image than the GD method currently in use
- or, a way of rejecting an image during upload if it is bigger than the dimensions set by the administrator so that resizing is avoided

Am running CPG 1.5.12.

Αndré

Quote from: 406man on March 04, 2011, 09:19:03 AM
A sharp image ends up being quite fuzzy after re-sizing and some of the users of my gallery complained about the results.
This plugin sharpens intermediate-sized images: http://forum.coppermine-gallery.net/index.php/topic,62435.0.html


Quote from: 406man on March 04, 2011, 09:19:03 AM
rejecting an image during upload if it is bigger than the dimensions set by the administrator so that resizing is avoided
Quote from: http://documentation.coppermine-gallery.net/en/configuration.htm#admin_picture_thumbnail_auto-resizeThere are three options:
    * No - Disabled. Coppermine won't resize the image for administrators and will return an error message for regular users.
    * Yes: Everyone - Enabled for all users, including the Admin during batch-add process.
    * Yes: User only - Enabled only for regular users

jsalab

Phill Luckhurst -
Sorry, but I have the latest version of CPG identifies himself as the latest version 1.5.9

http://coppermine-gallery.net/demo/cpg15x/
http://coppermine-gallery.net/demo/cpg15x/docs

When I have free time to make a video.

phill104

Why are you posting a link to our gallery? We know it says 1.5.9 at the top, that is from our custom theme. It says 1.5.12 at the botto which is the latest release.

Please post a link to your site.
It is a mistake to think you can solve any major problems just with potatoes.