Portfolio NetPublish and THE WATERMARK!! - Extensis.com


Portfolio NetPublish and THE WATERMARK!!

Wednesday March 5th, 2008 by Paul Krummenacker

So, the typical bane of all writers, what do I write? What do I have to say that people want to know, what is WORTHY of an RSS feed…

Ladies and Gentlemen, I give you: Portfolio NetPublish and THE WATERMARK!!

Watermarked ImageWith the release of Portfolio NetPublish 8.5 you can add an electronic watermark to your images that you display on your web site. I’m sure most everybody knows what an electronic watermark is (a semi-transparent image that overlays an image). Digital watermarking is to be barely visible, not interfering with the user experience of the content

The type of watermark that NetPublish will place on a target image is considered “destructive” (it becomes part of the file) to the downloaded file. It’s important to note that the watermark ONLY affects the file that is downloaded by web users and it does NOT alter, in any way, your original assets

To create a watermark image to be used with Portfolio NetPublish choose any non-animated GIF image to use as a watermark. In general, a high-contrast, simple image (such as those containing text) will perform better than complex, low-contrast images. Place this file in a location that is easily accessible (or even better, local) to the NetPublish server.

Windows: C:\Program Files\Extensis\Portfolio NetPublish Server\Web Root\watermarks
Macintosh: /Applications/Portfolio NetPublish Server/Web Root/watermarks

Portfolio NetPublish can apply a watermark to all image file types that can be dynamically scaled by NetPublish, including JPEG, GIF, PNG and BMP.

To use this feature, you need to edit the site.properties file using a text editor (such as BBEdit, Notepad, TextEdit, or even vi).

KEEP IN MIND, the site.properties file MUST retain the UTF-8 encoding format. This file is generated by the NetPublish Assistant whenever a site is published to the NetPublish web server.

The default location for this file on Windows is:
C:\Program Files\Extensis\Portfolio NetPublish Server\Web Root\site\<site name>\site.properties

The default location for this file on Macintosh is:
/Applications/Portfolio NetPublish Server/Web Root/site/<site name>/site.properties

The process of enabling Watermarking and asset download protection involves appending the necessary parameters to this file, selecting the options that you desire.

Now listen up, here’s the tricky part!

The watermark transparency pixel

The transparency of the watermark is determined by the upper-left corner pixel of the watermark GIF. The color of that pixel determines what is considered the “background” and thus transparent part of the watermark. It’s important to note that any alpha channels are ignored, and transparency is entirely determined by the upper left pixel.

Ok, now in English. Say you want to have a nice watermark that say ‘Copyright 2008, keep your grubby mitts off’ you need to create that file, in GIF format but make sure the upper left corner pixel is blank, or transparent. When Portfolio NetPublish looks at the image to be used as the watermark it knows to pick that pixel as the sample of the parts to knock out of the image when overlaying the watermark. Think of it like the blue screen process that they use in movies or on the nightly news with the weather map.

The easiest way to do this is to create a new image in an image editor (like Photoshop), create a new transparent GIF image. Slap whatever you want your watermark to say on the watermark image, and save the GIF. ONLY GIF’s work, don’t try a PNG, JPG or EPS.

You can set the alignment of where you want your watermark, as well as the opacity level. These are covered in depth in the Portfolio 8.5 User Guide update document. The opacity value can be any value from 0-100, and has a default setting of 50. This determines how opaque or transparent the watermark appears on the target image — from 0% where only the target image is visible (pointless) to 100% where only the watermark image is visible (pointless, again).

I usually shoot for about 40-60% tops for my opacity.

One other important thing to know, when you setup or change any part of your watermarking setup, you MUST clear the NetPublish site cache directory. This prevents NetPublish from inadvertently using previously generated (and possibly non-watermarked) images on the site.

So, there it is, it will take you a few times to get the hang of it, but soon, you’ll be watermarking with the best of them.

In other news, I did ride the scooter in again today, had to pile on the layers to stay warm, but it gave me time to think and come up with this blog post. With gas hitting $100+ a barrel, I think we’ll all be seeing more people on 2 wheels. I was asked by 2 people today at the gas station about my scooter. So, think about it, but whatever you do, get a good helmet and stay alert