Thumbnail image quality

[duncan12]

I am trying to see if there is a way I can improve the image quality of the thumbnails that are created from my product images. My client noticed that her images, when displayed in the main product categories layout, looked fuzzy. I didn't believe her. So I tested. I resized the main product image myself using Apple Preview and then compared with the VM resized image at the exact same size.

The client was right. The image is fuzzy. 

So, how does VM do the resizing? Is it done on the fly with a stock PHP function? Is it possible to replace or upgrade that function?

Any guidance would be appreciated.

[vaskern]

Yes, I notice it too. Seems most people prefere to scale them outside of VM. Here is a thread here about this issue.

[jenkinhill]

See http://forum.virtuemart.net/index.php?topic=118111.msg400054#msg400054

[Studio 42]

The current problem is not only the quality but the quantity.
I (lossless) reduced with an external tool my PNG files(200x200) from min 200kb to  max 18kb.
This give me 10 point more on google pagespeed in most case.

[duncan12]

JenkinHill thanks, but I have the new version of VirtueMart. Is this php file/function located somewhere else now?

Nevermind. It is still there. I needed to look in administrator/components/com_virtuemart/helpers. Thanks!

[duncan12]

WOW!!! Bad News. DO NOT TRY THIS!!!!

I followed the directions and deleted my resized thumbnails from images/stories/virtuemart/product/resized. I turned "dynamic resizing" on in virtuemart. Then I revisited the product pages, expecting the images to be re-rendered. OOPS!!! Bad news. The page won't render at all now. It is just a 100% empty html document. I went into the back-end to look at the product and maybe upload the pics. OOPS!!! the back end product pages won't render... just 100% empty html documents.

What the #$&*!!

Luckily, I saved the images, and I moved them back into place and my site is restored. But I pity the hapless fellow that tries to do this without having all the images backed up first.

So, my question remains. How do I delete my thumbnails and get them re-rendered?

[GJC Web Design]

I just did this on a site I'm working on -- just had dynamic checked and changed the size ..
deleted nothing .. all thumbs renewed

[Studio 42]

Hi,
Virtuemart resize all displayed image in one time. I think the max execution time is to low or your server is to slow.
Check if some thumb are added in the resied folder, even if you have a blank page.
If this is the case, then try to refresh your page.
To solve the problem, you can change your max execution time and memory in your php.ini file.
max_execution_time = 120     ; Maximum execution time of each script, in seconds
memory_limit = 8M      ; Maximum amount of memory a script may consume (8MB)

WOW!!! Bad News. DO NOT TRY THIS!!!!

the back end product pages won't render... just 100% empty html documents.

What the #$&*!!

Luckily, I saved the images, and I moved them back into place and my site is restored. But I pity the hapless fellow that tries to do this without having all the images backed up first.

So, my question remains. How do I delete my thumbnails and get them re-rendered?

[nikki021]

I consider it a valuable help and hope this will help me to fix gallery page thumbnails.