I have only just noticed that Google’s Reference Guide contains some information regarding Picasa Web Albums parameters in this, here: http://code.google.com/apis/picasaweb/reference.html#Parameters

To quote the reference (as of the time of writing this):

32, 48, 64, 72, 144, 160

 

The following values are valid for the thumbsize and imgmax query parameters and are embeddable on a webpage. These images are available as only uncropped(u) sizes by appending u to the size or just passing the size value without appending anything.

200, 288, 320, 400, 512, 576, 640, 720, 800

The following values are valid for the thumbsize and imgmax query parameters and are not embeddable on a webpage. These image sizes are only available in uncropped format and are accessed using only the size (no u is appended to the size).

912, 1024, 1152, 1280, 1440, 1600

There is an additional size d which results in the elements referencing the original uploaded photo, including all original Exif data. It is valid only for use with the imgmax query parameter.

These query parameters are used when retrieving the feeds in order to get images of the appropriate sizes. They cannot be used when retrieving the actual images. Example URL using the imgmax parameter: http://picasaweb.google.com/data/feed/api/user/userID/album/albumName?imgmax=912”

So what does that mean?

Personally I’m only interested in “hotlinking” using a URL like this:

http://lh6.google.com/james.laugesen/ReV6ymoCUZI/AAAAAAAAFvk/bk1mXJZJyfk/s800/050620%20055.jpg

And that appears to still work fine - my previous post still works.

Sam’s post uses the ‘imgmax’ query parameter instead, and it still works too: http://lh6.google.com/james.laugesen/ReV6ymoCUZI/AAAAAAAAFvk/bk1mXJZJyfk/050620%20055.jpg?imgmax=800

So I am a little confused by Google’s reference… will our hotlinks start to break? I understand it is a Google Picasa API Reference, covering feeds, etc. But I don’t understand how “embeddable on a webpage” could refer to anything other than hotlinking an image. Or maybe someone can show me how to embed an RSS feed into a webpage? :-|