Video Special Effects - Part 3: Chroma Key and Movement Effects

Continued from Part 2.

The following video tutorial demonstrates how chroma-key and movement effects were incorporated into the above special effects video using VSDC Free Video Editor.  This includes the application of movement, zoom, and transparency effects to simulate a UFO approaching at great speed from a great distance.  Everything demonstrated in this video is summarized in the below article.  Each paragraph includes hyperlinks to specific sections within the video to help the reader follow these instructions with video examples.


Note that VSDC downloader will suggest installing additional bundled software along with VSDC.  This is why VSDC is free. Carefully read those installation screens and make sure to uncheck or decline any software that doesn't interest you (probably all). 
(VSDC download link click here).  

The UFO green screen effect is first placed on the screen by opening its video clip file from within the program.  It is placed on the work mat by holding down the left mouse button, and moving the mouse to roughly size the effect on the mat.

Now we apply chroma keying to remove the green color background from the UFO effect clip. Click on the Video tab. In the menus, select Editor / Video Effects / Transparent Background Remover.  If your background color is green, most of the color should disappear with this selection leaving a small residual ring around the perimeter of the UFO.  Keep in mind any background color can be made invisible (not just green).  If your background is different than green (say Blue), open the properties window, and click on "Get color from scene".  Use the eyedropper sampler tool to click on and set the invisible background color.

Removing residual color. If there is a residual ring of color around the UFO, in the properties window adjust Brightness Threshold, ChromacityU, and ChromacityV until it disappears.  This will require a little finesse and practice to best balance these three setting until the desired effect is achieved.  

With the background now invisible, we can now fine-tune the placement of our effect on the screen.  Click on the Scene tab, then click on and hold the mouse button down on the UFO effect.  Adjust its placement by moving the mouse.

A movement effect can now be added. Click on the Video tab above the timeline, then move the cursor to the beginning of the Video timeline.  In the menu, select Add Object / Movement.  Move the mouse cursor to where you'd like the movement to start, then hold down the left mouse button, and move the cursor to where you'd like the movement to end.  The speed of the movement can be adjusted by adjusting the length of the movement bar.  A longer bar = slower, shorter = faster.

We can use the Zoom effect to enhance the simulation of an approaching UFO.  We'd like our UFO to be small at the start, and as it gets closer, we'd like it to get bigger.  Click on the Video tab, and move the timeline cursor to the beginning of the Video timeline.  In the menu, select Video Effects / Transform / Zoom.  Adjust the Zoom timeline bar to the same length as the Movement bar.  Click on the Zoom bar, and then open the Properties window.  Set X, Y Start values for Zoom to 0, and X, Y End values for Zoom to 100.  This will make the UFO very tiny at the start of movement, and it will grow to full size at the end of movement.

We can also apply a little transparency effect to further enhance the effect of the UFO approaching from very far away. Click on the Video tab above the timeline, and move the cursor to the beginning of the timeline.  In the menu, select Video Effects / Transparent / Custom. Adjust the Transparency timeline bar to the same length as the Movement bar.  Click on the Transparency bar, and then open the properties window. Adjust Transparency Start to some mid value (such as 42) and End value to 100.  This will make the UFO semi-transparent at the start, making it somewhat hard to see at the beginning of its run.  But as it gets close, it will become more solid and more well defined.

To be continued in Part 4.