Chapter 11. Examples

Table of Contents

1. Create a mask with The Gimp
1.1. Download and open a Webcampak picture

1. Create a mask with The Gimp

In this small example we are going to show you how to create a mask with Gimp. This mask will be a PNG picture with an Alpha channel (transparency).

Those manipulations are detailed with The Gimp but can be adapted to most picture manipulation software.

Before beginning this example, just ensure your Webcampak is installed in its final location (if something moves you might have to re-create the mask).

In this example we are going to create a mask to hide some portions of the picture to keep only a few building sites. This is especially useful if you want to filter shots during a video creation.

1.1. Download and open a Webcampak picture

Log into your Webcampak and download a full size picture (i.e.via FTP or using "Downl. Original" in the viewer interface).

Open this picture with The Gimp.

Figure 11.1. Open source picture

Open source picture

1.1.1. Insert a transparent layer

Figure 11.2. Insert a transparent layer

Insert a transparent layer

Figure 11.3. Create a new layer

Create a new layer

Ensure you select "Transparency" here.

Figure 11.4. Display layers

Display layers

1.1.2. Color background

Add a color background on this new layer, once done ensure you can't see the picture behind the layer.

Figure 11.5. New layer with color

New layer with color

Change "Opacity" of the layer to see the background picture.

Figure 11.6. Change opacity of the layer

Change opacity of the layer

1.1.3. Erase areas you want to monitor

Using delete tool, erase areas of the new layer containing elements you want to monitor

Figure 11.7. Erase sections to monitor

Erase sections to monitor


Configure "Opacity" back to 100, you should now only see areas you want to monitor.

Figure 11.8. Opacity at 100 on new layer

Opacity at 100 on new layer


1.1.4. Delete source layer and save

Then we will delete the source layer, do a right click on "Background" and select "Delete Layer".

Figure 11.9. Delete background layer

Delete background layer


You mask is ready to be saved, in PNG and keeping Alpha channel.

Figure 11.10. Save picture

Save picture


Transfer the mask, via FTP, to /watermark/ directory using global FTP account (wpresources).