Disallow thumbnails in robots.txt

Not as is. You'd either have to hack core files and reapply those updates after every upgrade or I think you could hack something like that in a theme and .htaccess without having to modify core files, but it could mean more maintenance in the future. See below for a rough working model of this. Visit my site today only to see an example (the top image is the "/thumb/path/to/image.jpg" thumbnail)

This is just a rough sketch.
http://codex.gallery2.org/Gallery2:Editing_Templates

album.tpl edit:
<img src="/thumb/{$child.thumbnail.id}-{$child.thumbnail.serialNumber}/{$child.pathComponent}
NOTE: that, as is only works for thumbnails of images and not thumbnails of albums. You'd need to write a little bit more logic to check if the item can contain children and at a ".jpg" to the end of the pathComponent. Of course I'm also assuming that the album highlight is always a jpg and that it's always going to be ".jpg" and not ".JPG" or ".jpeg" or ."JPEG or any other sort of combination let alone a .gif or .png.

.htaccess edit, add this rule to .htaccess

    RewriteCond %{THE_REQUEST} /thumb/([0-9]+)-([0-9]+)/([^/?]+)(\?.|\ .)
    RewriteCond %{REQUEST_URI} !/main\.php$
    RewriteRule .   /main.php?g2_view=core.DownloadItem&g2_itemId=%1&g2_serialNumber=%2&g2_fileName=%3   [QSA,L]

I'm no rewrite rule expert, but I'm pretty sure you'll either need to duplicate some of the current rewrite rules to another section of .htaccess that Gallery doesn't write to when you make changes in Site Admin > URL Rewrite or you'll have to reapply those changes every time you modify URL Rewrite if you add those 2 conditions and rule to the existing set of rewrite rules.

I'll leave my site up like this for a day, visit my site and you'll see double thumbnails of any image. I even added in logic to handle album thumbnails and image frames:

Here's my edits to album.tpl My additions are in red I would remove, for a production site, what I've highlighted in green

                  {if isset($theme.params.$frameType) && isset($child.thumbnail)}
                    {g->container type="imageframe.ImageFrame" frame=$theme.params.$frameType
                                  width=$child.thumbnail.width height=$child.thumbnail.height}
                      <a href="{$linkUrl}">
{if ($child.canContainChildren || $child.entityType == 'GalleryLinkItem')}
  <img id="%ID%" src="/thumb/{$child.thumbnail.id}-{$child.thumbnail.serialNumber}/{$child.pathComponent}.jpg">
{else}
  <img id="%ID%" src="/thumb/{$child.thumbnail.id}-{$child.thumbnail.serialNumber}/{$child.pathComponent}">
{/if}

                        {g->image id="%ID%" item=$child image=$child.thumbnail
                         class="%CLASS% giThumbnail"}
                      </a>
                    {/g->container}
                  {elseif isset($child.thumbnail)}
                    <a href="{$linkUrl}">
{if ($child.canContainChildren || $child.entityType == 'GalleryLinkItem')}
  <img src="/thumb/{$child.thumbnail.id}-{$child.thumbnail.serialNumber}/{$child.pathComponent}.jpg">
{else}
  <img src="/thumb/{$child.thumbnail.id}-{$child.thumbnail.serialNumber}/{$child.pathComponent}">
{/if}

                      {g->image item=$child image=$child.thumbnail class="giThumbnail"}
                    </a>
                  {else}
                    <a href="{$linkUrl}" class="giMissingThumbnail">
                      {g->text text="no thumbnail"}
                    </a>
                  {/if}

Even tested with Image Frames.

Edit: Then of course edit your robots.txt file.

NOTE: this is at theme level so if you change themes, while nothing should break, google will be able to index those images again if you don't apply these changes to the theme you are using.

I made those changes to the Matrix (default) theme.

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It didn't start out that way I was just going to write 2 or 3 quick sentences with a code snippet, but it turned into a fun exercise.

Glad it worked. I'll be removing those changes from my site now (in case anyone else is watching this thread and wondering why they are not seeing what I've described above)

I don't know if it is the ideal solution, I'm pretty sure it's not, but it works. You may need to make changes to this if there are ever major changes to the template engine for Gallery.

I got the smarty variable information from setting Gallery into debug mode:
FAQ: How to set/use Gallery in debug mode?

Once Gallery is in debug mode a Smarty Debug pop-up window will appear.
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About the Image Block, I don't have a clue. I'll have to play around with that on my server, I could have sworn with URL Rewrite enabled that on my install Image Block used the short, pretty named URLs.

As for the album/subalbum thing can you post a link to a specific album where you are seeing this?
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Don't put spaces in file names ;)

As a general rule of thumb I never put spaces in filenames, underscores, dashes or CamelCase are what I use, it sure makes life a lot easier and breaks a lot less things.

But can you post a link where you see this?
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My idea is to dump the use of spaces and use dashes or underscores in file and folder (album) names. ;) IMO, spaces in file and directory names are just a bad idea even more so on anything web related.

I'm not going to spend any time trying to figure out a way to hack or code around the use of spaces.
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