5 Replies Latest reply on Dec 14, 2006 4:15 AM by Newsgroup_User

    Prepping images for the web

    johngordon12 Level 1
      Not sure if this is necessarily the best forum to ask, but wonder if anyone might have any tips.

      Basically I've been working on a site for a guy who is importing rugs from China. I suspect the problem is that the images he's supplies me with aren't taken from the best angle - it taken with the rugs hanging on a wall, so that they're straight on.

      I've used GD to redraw the original images as thumbs, which works well enough, but it's pretty clear that the thumb images aren't as good as I've seen on other sites.

      As an example, this is an example of the site and images I've been working on / with :

      example

      And this is an example of what are clearer, more straight on images :

      example 2

      Any tips on anything I can be doing to prep the images a bit better would be greatly appreciated.

      Cheers,
      Iain
        • 1. Re: Prepping images for the web
          Level 7
          The images in your first link have way too much sharpening applied, way too
          much.

          Peter
          ______________________________
          "Iain71" <webforumsuser@macromedia.com> wrote in message
          news:elptt2$2jc$1@forums.macromedia.com...
          | Not sure if this is necessarily the best forum to ask, but wonder if
          anyone
          | might have any tips.
          |
          | Basically I've been working on a site for a guy who is importing rugs from
          | China. I suspect the problem is that the images he's supplies me with
          aren't
          | taken from the best angle - it taken with the rugs hanging on a wall, so
          that
          | they're straight on.
          |
          | I've used GD to redraw the original images as thumbs, which works well
          enough,
          | but it's pretty clear that the thumb images aren't as good as I've seen on
          | other sites.
          |
          | As an example, this is an example of the site and images I've been working
          on
          | / with :
          |
          | http://www.oriental-chamber.co.uk/persian.php
          |
          | And this is an example of what are clearer, more straight on images :
          |
          | http://www.ghfrith.com/index.php?p0=rug
          |
          | Any tips on anything I can be doing to prep the images a bit better would
          be
          | greatly appreciated.
          |
          | Cheers,
          | Iain
          |


          • 2. Re: Prepping images for the web
            johngordon12 Level 1
            Sharpening sounds about right. Trouble is, I haven't modified the images (manually at least) at all.

            If you click through to the details page, and then click to view the full size, original image, that image is basically being redrawn using GD image library, a PHP script which - on the face of it - seemed a great tool that you can use to automatically manipulate images on different pages.

            ie - you can upload the full size image to the site, and then use GD to redraw the image - very handy to generate thumbnails that retain their original ratios - as it is doing on the gallery and details pages.

            Downside appears to be this quality issue.

            Looks like it might be one of those things where you can't have the pros of automating image generation and retaining control over quality versus manually prepping the images but regaining that control.

            Iain
            • 3. Re: Prepping images for the web
              Level 7
              On Thu, 14 Dec 2006 13:16:06 +0300, Iain71 <webforumsuser@macromedia.com>
              wrote:

              > Sharpening sounds about right. Trouble is, I haven't modified the images
              > (manually at least) at all.
              >
              > If you click through to the details page, and then click to view the
              > full
              > size, original image, that image is basically being redrawn using
              > http://www.boutell.com/gd/, a PHP script which - on the face of it -
              > seemed a
              > great tool that you can use to automatically manipulate images on
              > different
              > pages.
              >
              > ie - you can upload the full size image to the site, and then use GD to
              > redraw
              > the image - very handy to generate thumbnails that retain their original
              > ratios
              > - as it is doing on the gallery and details pages.
              >
              > Downside appears to be this quality issue.

              Do a simple test:

              Take one of the original images into FW, go to Modify -> Canvas -> Image
              Size, set desired target size and use "Bicubic" as interpolation
              algorithm. You'll see quite nice looking image.

              Repeate the test, now using "Nearest Neighbour" as interpolation
              algorithm. You'll see exactly the junk you now have on your site.

              Conclusion: the script you are using utilizes the fastest, yet the worst
              possible interpolation technique. I have no idea whether the script can be
              reconfigured to use different algorithm. If yes, you're lucky - change it
              to "bicubic" or "bilinear". If no, you still may try using FW's File ->
              Batch Process feature to generate small images.

              --
              Ilya Razmanov
              http://photoshop.msk.ru - Photoshop plug-in filters
              • 4. Re: Prepping images for the web
                johngordon12 Level 1
                Cheers for the replies.

                I probably should have said more about GD, as it's a PHP thing really.

                It turns out that I was using imageresized() as a function, when there's another function imageresampled() that does a bit more to retain quality - and that seems to have smoothed them out quite a bit on another project I'm working on here - so hopefully will improve the rug images quite a bit too.
                • 5. Re: Prepping images for the web
                  Level 7
                  On Thu, 14 Dec 2006 15:02:01 +0300, Iain71 <webforumsuser@macromedia.com>
                  wrote:

                  > I probably should have said more about GD, as it's a PHP thing really.

                  It wouldn't help much since I'm not going to learn PHP :-) Image
                  processing math, however, remains the same regardless of that do I use C
                  or do you use PHP. Choosing most appropriate math seem to be the source of
                  the problem in your case.

                  > It turns out that I was using imageresized() as a function, when there's
                  > another function imageresampled() that does a bit more to retain quality
                  > - and
                  > that seems to have smoothed them out quite a bit on another project I'm
                  > working
                  > on here - so hopefully will improve the rug images quite a bit too.

                  Sounds like that's exactly what you are looking for. If it does anything
                  better than "nearest neighbour" - that's what you need. Your images
                  contain a lot of high frequency detail, and rough sampling with "nearest
                  neighbour" is definitely the worst choice for them, so about anything more
                  sophisticated should give noticeable improvement.

                  --
                  Ilya Razmanov
                  http://photoshop.msk.ru - Photoshop plug-in filters