Published in Digit magazine August 1998

 

Layer Masking and Special Effects

with Satori v1.6

Introduction

This tutorial series is intended to serve as an introduction to Satori, resolution independent paint & graphics software for Windows 95 and Windows NT. In each tutorial, Mark Graham provides a step by step guide to some of the unique object-oriented design and editing features.

In the first tutorial, we covered the basic topics of image compositing, chroma-keying and text editing. For this second tutorial, Mark will show you how to use masking techniques to create special effects.

Here’s a technique you can use to add brilliant plasma glows to spaceships or to give your favourite aunt a saintly aura by dint of a little judicious masking!

For this you’ll need a background and a 32 bit file of some kind - I’m using an image of rocks for my background and a clip from an animation rendered in 3D Studio Max of Olaf (a Troll) walking and saved to local disk as 32 bit TGA files.

Pic1.bmp (2986038 bytes)

"Olaf the Troll was first rendered in 3d Studio Max"

pic2.jpg (16249 bytes)

"A suitably Trollish scene..."

 

Satori FilmFX supports ROTOSCOPING so we can apply the glow effect across the whole clip such that wherever Olaf moves his glow stays with him - like a bad smell!.

OK, so here’s what you do...Load the background into layer 1 and load the 32 bit file into layer 2 using the LOAD TO LAYER commands. Where Satori detects a sequence of incrementing files the FILENAME ANIMATION dialogue will be launched where FilmFX users can set various animation parameters.

 

 

pic3.jpg (20577 bytes)

"Here’s Olaf the Troll before we mess with him. Would YOU mess with him?"

pic4.jpg (17716 bytes)

"Olaf blends too well into his background - we’ll soon put a stop to that!"

 

Next make a new empty layer (it’s a good idea to name this new layer as "GLOW") and fill it with yellow by selecting that colour and placing it in the CLEAR LAYER colour box on the LAYER menu and then clicking CLEAR LAYER.

Next from the LOAD TO LAYER dialogue click LOAD TO CURRENT LAYER USER MASK and select the same 32 bit file (or sequence) as before. This has the effect of punching a (troll-shaped) hole (mask) in the yellow colour channel. You can invert this to produce a yellow silhouette for Olaf by clicking on the INVERT MASK icon on the LAYER LIST palette. The next step is to apply a blur in the user mask channel (be sure to apply this to the mask channel NOT the colour channel) - From the GEOMETRY menu click MASK, from the SHAPE tab click the RECTANGLE tool and from the FX-1 tab click BLUR (set the spinners to 10) then click the pen/mouse right button inside the image window and click FILL CANVAS. The result will be a visible blurring of the yellow silhouette.

Next Page