INSTALLATION INSTRUCTIONS:
Place this script in any web accessible directory on your web server along with some photos/images and (if you wish) some sub-directories& let fly! You may configure using the options below or simply use it with the defaults.

IMPORTANT!!!
In order for the script to write it's data files (ie: if you have popularity or user comments turned on) you MUST do one of the following (this doesn't apply to Windows systems) or the script will fail:

A) Change the owner of the script to the user/group that the web server is running as (eg: chown nobody.nobody). This is the most secure method, but usually requires admin access.

or...

B) Set all the directories that contain photos to world-readable (eg: chmod 777). This is (of course) less secure, but usually doesn't require admin access, so may be more plausible if you are a user on someone else's system.

NOTES:

Thumbnails
You can use thumbnails by placing smaller versions (I use 100x100) of the photos with the EXACT same filename (case IS sensitive) in a directory named "thumbs" (or whatever you specify in the settings below). This directory MUST be in the same directory as the images they are thumbnails for. ie:
Base Folder (with images and this script)
image1.jpg
image2.JPG
Image3.gif
index.php3
thumbs (thumbnail directory)
image1.jpg
image2.JPG
Image3.gif

File Naming
The script will replace underscore characters (_) in filenames and directories with spaces and capitalize the first character of each word. So to have an album called "My Family Photos", simply create a directory named "my_family_photos".

Album/Page Comments
You may place commentary files in each directory named "comments.txt" (or whatever you specify in the variables below) which will be displayed on the directory listing pages near the top. You may use HTML markup in these files but you need not use <br> or <p> tags as they are automatically added to the end of each line.

Photo Notes
You may add notes to each image by placing a text file with the name "<photoname>.<photoext>.<notesext>" (you may specify what <notesext> is below - default is "notes"). For example, you want to add come notes to the image "image1.jpg" so you create a text file in the same directory named "image1.jpg.notes". This file will be read and placed below the image when viewed. Same rules apply as above regarding HTML, <p>, and <br>.

Visitor Comments
Any comments that visitors add will be stored in files in the same directory as the images and use the format "<photoname>.<photoext>.<commentsext>" (or whatever you specify below for <commentsext> - default is "comments"). For example, a user leaves a comment about an image named "image1.jpg". Their comments would be stored in a text file named "image1.jpg.comments".